GUI enabling/disabling of controls
In addition to fundamental GUI component interaction, an application should dynamically enable and disable GUI components, to give some guidance to the user, and prohibit (inter)actions which are inappropriate in the current state of the application.
You are encouraged to solve this task according to the task description, using any language you may know.
- Task
Similar to the task GUI component interaction, write a program that presents a form with three components to the user:
- a numeric input field ("Value")
- a button ("increment")
- a button ("decrement")
The field is initialized to zero. The user may manually enter a new value into the field, increment its value with the "increment" button, or decrement the value with the "decrement" button.
The input field should be enabled only when its value is zero. The "increment" button only as long as the field's value is less then 10: When the value 10 is reached, the button should go into a disabled state. Analogously, the "decrement" button should be enabled only as long as the value is greater than zero.
Effectively, the user can now either increment up to 10, or down to zero. Manually entering values outside that range is still legal, but the buttons should reflect that and enable/disable accordingly.
disabling.adb:
with Ada.Strings.Fixed; with Gtk.Main; with Gtk.Handlers; with Gtk.Button; with Gtk.Window; with Gtk.GEntry; with Gtk.Editable; with Gtk.Box; with Gtk.Widget; with Glib.Values; procedure Disabling is type My_Natural is range 0 .. 10; The_Value : My_Natural := 0; Main_Window : Gtk.Window.Gtk_Window; Content : Gtk.Box.Gtk_Vbox; Increment_Button : Gtk.Button.Gtk_Button; Decrement_Button : Gtk.Button.Gtk_Button; Entry_Field : Gtk.GEntry.Gtk_Entry; package Entry_Callbacks is new Gtk.Handlers.Callback (Gtk.GEntry.Gtk_Entry_Record); package Button_Callbacks is new Gtk.Handlers.Callback (Gtk.Button.Gtk_Button_Record); package Window_Callbacks is new Gtk.Handlers.Return_Callback (Gtk.Window.Gtk_Window_Record, Boolean); -- update displayed text procedure Update_Entry is begin Gtk.GEntry.Set_Text (The_Entry => Entry_Field, Text => Ada.Strings.Fixed.Trim (Source => My_Natural'Image (The_Value), Side => Ada.Strings.Both)); end Update_Entry; procedure Check_Value is begin Gtk.Widget.Set_Sensitive (Gtk.Widget.Gtk_Widget (Decrement_Button), The_Value > 0); Gtk.Widget.Set_Sensitive (Gtk.Widget.Gtk_Widget (Increment_Button), The_Value < 10); Gtk.Widget.Set_Sensitive (Gtk.Widget.Gtk_Widget (Entry_Field), The_Value = 0); end Check_Value; procedure On_Changed_Text (Object : access Gtk.GEntry.Gtk_Entry_Record'Class; Params : Glib.Values.GValues) is pragma Unreferenced (Params, Object); begin The_Value := My_Natural'Value (Gtk.GEntry.Get_Text (Entry_Field)); Check_Value; Update_Entry; exception when Constraint_Error => The_Value := 0; end On_Changed_Text; -- make sure that only numbers are entered procedure On_Insert_Text (Object : access Gtk.GEntry.Gtk_Entry_Record'Class; Params : Glib.Values.GValues) is Length : constant Glib.Gint := Glib.Values.Get_Int (Glib.Values.Nth (Params, 2)); Text : constant String := Glib.Values.Get_String (Glib.Values.Nth (Params, 1), Length); begin declare Number : My_Natural; pragma Unreferenced (Number); begin Number := My_Natural'Value (Text); exception when Constraint_Error => -- refuse values that are not parsable Gtk.Handlers.Emit_Stop_By_Name (Object => Object, Name => Gtk.Editable.Signal_Insert_Text); end; end On_Insert_Text; -- Callback for click event procedure On_Increment_Click (Object : access Gtk.Button.Gtk_Button_Record'Class) is pragma Unreferenced (Object); begin The_Value := The_Value + 1; Check_Value; Update_Entry; end On_Increment_Click; -- Callback for click event procedure On_Decrement_Click (Object : access Gtk.Button.Gtk_Button_Record'Class) is pragma Unreferenced (Object); begin The_Value := The_Value - 1; Check_Value; Update_Entry; end On_Decrement_Click; -- Callback for delete event function On_Main_Window_Delete (Object : access Gtk.Window.Gtk_Window_Record'Class) return Boolean is pragma Unreferenced (Object); begin Gtk.Main.Main_Quit; return True; end On_Main_Window_Delete; begin Gtk.Main.Init; Gtk.GEntry.Gtk_New (Widget => Entry_Field); Entry_Callbacks.Connect (Widget => Entry_Field, Name => Gtk.Editable.Signal_Insert_Text, Cb => On_Insert_Text'Access); Entry_Callbacks.Connect (Widget => Entry_Field, Name => Gtk.Editable.Signal_Changed, Cb => On_Changed_Text'Access); Gtk.Button.Gtk_New (Button => Increment_Button, Label => "Increment"); Gtk.Button.Gtk_New (Button => Decrement_Button, Label => "Decrement"); Button_Callbacks.Connect (Widget => Increment_Button, Name => Gtk.Button.Signal_Clicked, Marsh => Button_Callbacks.To_Marshaller (On_Increment_Click'Access)); Button_Callbacks.Connect (Widget => Decrement_Button, Name => Gtk.Button.Signal_Clicked, Marsh => Button_Callbacks.To_Marshaller (On_Decrement_Click'Access)); Gtk.Box.Gtk_New_Vbox (Box => Content); Gtk.Box.Add (Container => Content, Widget => Entry_Field); Gtk.Box.Add (Container => Content, Widget => Increment_Button); Gtk.Box.Add (Container => Content, Widget => Decrement_Button); Gtk.Window.Gtk_New (Window => Main_Window); Gtk.Window.Add (Container => Main_Window, Widget => Content); Window_Callbacks.Connect (Widget => Main_Window, Name => Gtk.Widget.Signal_Delete_Event, Cb => On_Main_Window_Delete'Access); Gtk.Window.Show_All (Widget => Main_Window); Update_Entry; Gtk.Main.Main; end Disabling; GUI, Add, Edit, w150 number vValue gEnableDisable, 0 ; Number specifies a numbers-only edit field. g<Subroutine> specifies a subroutine to run when the value of control changes. GUI, Add, button,, Increment GUI, Add, button, xp+70 yp, Decrement ; xp+70 and yp are merely positioning options GUI, Show, w200 y200, Title ; Shows the GUI. Add your own title if you wish ;No timer is needed return ; ----------End Auto-Execute Section---------- ButtonIncrement: GUI, Submit, NoHide ; "Set the contents of each variable to the contents of their corresponding controls without hiding the GUI" If ( value < 10 ) ; Just in case EnableDisable didn't disable the button it in time. Value++ ; Increment Value GUIControl,, Value, %value% ; "Set the text of the control which alters the variable 'value' to the contents of 'value'" return ButtonDecrement: GUI, Submit, Nohide If value > 0 Value-- GuiControl,, Value, %value% return EnableDisable: GUI, Submit, Nohide If ( value < 10 ) GuiControl, enable, Increment Else GuiControl, disable, Increment If ( value > 0) GuiControl, enable, Decrement Else GuiControl, disable, Decrement If ( value = 0 ) GuiControl, enable, Edit1 Else GuiControl, disable, Edit1 return GuiClose: ExitApp ; Ensures the script ends when the GUI is closed. This code requires BaCon 4.0.1 or higher.
OPTION GUI TRUE PRAGMA GUI gtk3 gui = GUIDEFINE(" \ { type=WINDOW name=window callback=delete-event title=\"Rosetta Code\" width-request=200 } \ { type=BOX name=box parent=window orientation=GTK_ORIENTATION_VERTICAL } \ { type=SPIN_BUTTON name=spin parent=box numeric=TRUE } \ { type=BUTTON_BOX name=bbox parent=box } \ { type=BUTTON name=increment parent=bbox callback=clicked label=\"Increment\" } \ { type=BUTTON name=decrement parent=bbox callback=clicked label=\"Decrement\" } ") CALL GUISET(gui, "spin", "adjustment", gtk_adjustment_new(0, 0, 10, 1, 1, 0)) CALL GUISET(gui, "decrement", "sensitive", FALSE) DECLARE input TYPE FLOATING WHILE TRUE CALL GUIGET(gui, "spin", "value", &input) SELECT GUIEVENT$(gui) CASE "increment" INCR input CASE "decrement" DECR input CASE "window" BREAK ENDSELECT CALL GUISET(gui, "spin", "value", input) CALL GUISET(gui, "decrement", "sensitive", IIF(input <= 0, FALSE, TRUE)) CALL GUISET(gui, "increment", "sensitive", IIF(input > 9, FALSE, TRUE)) CALL GUISET(gui, "spin", "sensitive", IIF(input = 0, TRUE, FALSE)) WEND INSTALL @lib$+"WINLIB2" INSTALL @lib$+"WINLIB5" ES_NUMBER = 8192 form% = FN_newdialog("Rosetta Code", 100, 100, 100, 52, 8, 1000) idInc% = FN_setproc(PROCinc) idDec% = FN_setproc(PROCdec) PROC_static(form%, "Value:", 100, 10, 10, 24, 14, 0) PROC_editbox(form%, "0", 101, 40, 8, 52, 14, ES_NUMBER) PROC_pushbutton(form%, "Increment", idInc%, 7, 30, 40, 16, 0) PROC_pushbutton(form%, "Decrement", idDec%, 52, 30, 40, 16, 0) PROC_showdialog(form%) REPEAT WAIT 1 SYS "GetDlgItemInt", !form%, 101, 0, 1 TO number% SYS "GetDlgItem", !form%, 101 TO hedit% SYS "EnableWindow", hedit%, number% = 0 SYS "GetDlgItem", !form%, idInc% TO hinc% SYS "EnableWindow", hinc%, number% < 10 SYS "GetDlgItem", !form%, idDec% TO hdec% SYS "EnableWindow", hdec%, number% > 0 UNTIL !form% = 0 QUIT DEF PROCinc LOCAL number% SYS "GetDlgItemInt", !form%, 101, 0, 1 TO number% SYS "SetDlgItemInt", !form%, 101, number% + 1, 1 ENDPROC DEF PROCdec LOCAL number% SYS "GetDlgItemInt", !form%, 101, 0, 1 TO number% SYS "SetDlgItemInt", !form%, 101, number% - 1, 1 ENDPROC - Output:
file main.c
#include <windows.h> #include "resource.h" #define MIN_VALUE 0 #define MAX_VALUE 10 BOOL CALLBACK DlgProc( HWND hwnd, UINT msg, WPARAM wPar, LPARAM lPar ); void Increment( HWND hwnd ); void Decrement( HWND hwnd ); void SetControlsState( HWND hwnd ); int WINAPI WinMain( HINSTANCE hInst, HINSTANCE hPInst, LPSTR cmdLn, int show ) { return DialogBox( hInst, MAKEINTRESOURCE(IDD_DLG), NULL, DlgProc ); } BOOL CALLBACK DlgProc( HWND hwnd, UINT msg, WPARAM wPar, LPARAM lPar ) { switch( msg ) { case WM_INITDIALOG: srand( GetTickCount() ); SetDlgItemInt( hwnd, IDC_INPUT, 0, FALSE ); break; case WM_COMMAND: switch( LOWORD(wPar) ) { case IDC_INCREMENT: Increment( hwnd ); break; case IDC_DECREMENT: Decrement( hwnd ); break; case IDC_INPUT: // update controls' state according // to the contents of the input field if( HIWORD(wPar) == EN_CHANGE ) SetControlsState( hwnd ); break; case IDC_QUIT: SendMessage( hwnd, WM_CLOSE, 0, 0 ); break; default: ; } break; case WM_CLOSE: { int reply = MessageBox( hwnd, "Do you really want to quit?", "Quit confirmation", MB_ICONQUESTION|MB_YESNO ); if( reply == IDYES ) EndDialog( hwnd, 0 ); } break; default: ; } return 0; } void Increment( HWND hwnd ) { UINT n = GetDlgItemInt( hwnd, IDC_INPUT, NULL, FALSE ); if( n < MAX_VALUE ) { SetDlgItemInt( hwnd, IDC_INPUT, ++n, FALSE ); SetControlsState( hwnd ); } } void Decrement( HWND hwnd ) { UINT n = GetDlgItemInt( hwnd, IDC_INPUT, NULL, FALSE ); if( n > MIN_VALUE ) { SetDlgItemInt( hwnd, IDC_INPUT, --n, FALSE ); SetControlsState( hwnd ); } } void SetControlsState( HWND hwnd ) { UINT n = GetDlgItemInt( hwnd, IDC_INPUT, NULL, FALSE ); EnableWindow( GetDlgItem(hwnd,IDC_INCREMENT), n<MAX_VALUE ); EnableWindow( GetDlgItem(hwnd,IDC_DECREMENT), n>MIN_VALUE ); } file resource.h
#define IDD_DLG 101 #define IDC_INPUT 1001 #define IDC_INCREMENT 1002 #define IDC_DECREMENT 1003 #define IDC_QUIT 1004 file resource.rc
#include <windows.h> #include "resource.h" LANGUAGE LANG_NEUTRAL, SUBLANG_NEUTRAL IDD_DLG DIALOG 0, 0, 154, 46 STYLE DS_3DLOOK | DS_CENTER | DS_MODALFRAME | DS_SHELLFONT | WS_CAPTION | WS_VISIBLE | WS_POPUP | WS_SYSMENU CAPTION "GUI Component Interaction" FONT 12, "Ms Shell Dlg" { EDITTEXT IDC_INPUT, 33, 7, 114, 12, ES_AUTOHSCROLL | ES_NUMBER PUSHBUTTON "Increment", IDC_INCREMENT, 7, 25, 50, 14 PUSHBUTTON "Decrement", IDC_DECREMENT, 62, 25, 50, 14, WS_DISABLED PUSHBUTTON "Quit", IDC_QUIT, 117, 25, 30, 14 RTEXT "Value:", -1, 10, 8, 20, 8 } Using Windows Forms; compile with csc -t:winexe Program.cs (on MS.NET) or gmcs -t:winexe Program.cs (on Mono)
using System; using System.ComponentModel; using System.Windows.Forms; class RosettaInteractionForm : Form { // Model used for DataBinding. // Notifies bound controls about Value changes. class NumberModel: INotifyPropertyChanged { // initialize event with empty delegate to avoid checks on null public event PropertyChangedEventHandler PropertyChanged = delegate {}; int _value; public int Value { get { return _value; } set { _value = value; // Notify bound control about value change PropertyChanged(this, new PropertyChangedEventArgs("Value")); } } } NumberModel model = new NumberModel{ Value = 0}; RosettaInteractionForm() { //MaskedTextBox is a TextBox variety with built-in input validation var tbNumber = new MaskedTextBox { Mask="0000", // allow 4 decimal digits only ResetOnSpace = false, // don't enter spaces Dock = DockStyle.Top // place at the top of form }; // bound TextBox.Text to NumberModel.Value; tbNumber.DataBindings.Add("Text", model, "Value"); var enabledIfZero = new Binding("Enabled", model, "Value"); EnableControlWhen(tbNumber, value => value == 0); var btIncrement = new Button{Text = "Increment", Dock = DockStyle.Bottom}; btIncrement.Click += delegate { model.Value++; }; EnableControlWhen(btIncrement, value => value < 10); var btDecrement = new Button{Text = "Decrement", Dock = DockStyle.Bottom}; btDecrement.Click += delegate { model.Value--; }; EnableControlWhen(btDecrement, value => value > 0); Controls.Add(tbNumber); Controls.Add(btIncrement); Controls.Add(btDecrement); } // common part of creating bindings for Enabled property void EnableControlWhen(Control ctrl, Func<int, bool> predicate) { // bind Control.Enabled to NumberModel.Value var enabledBinding = new Binding("Enabled", model, "Value"); // Format event is called when model value should be converted to Control value. enabledBinding.Format += (sender, args) => { // Enabled property is of bool type. if (args.DesiredType != typeof(bool)) return; // set resulting value by applying condition args.Value = predicate((int)args.Value); }; // as a result, control will be enabled if predicate returns true ctrl.DataBindings.Add(enabledBinding); } static void Main() { Application.Run(new RosettaInteractionForm()); } } with Qt 4.4, creating project file with qmake -project, Makefile with qmake -o Makefile <projectfile> and finally make
file task.h
#ifndef TASK_H #define TASK_H #include <QWidget> class QPushButton ; class QString ; class QLineEdit ; class QLabel ; class QVBoxLayout ; class QHBoxLayout ; class MyWidget : public QWidget { Q_OBJECT public: MyWidget( QWidget *parent = 0 ) ; private slots: void buttonChange( const QString & ) ; void addField( ) ; void subtractField( ) ; private : QVBoxLayout *thisWidgetLayout ; QLabel *instruction ; QPushButton *increment ; QPushButton *decrement ; QLineEdit *entryField ; QHBoxLayout *lowerPart ; } ; #endif file task.cpp
#include <QtGui> #include <QString> #include "task.h" MyWidget::MyWidget ( QWidget *parent ) : QWidget( parent ) { thisWidgetLayout = new QVBoxLayout ( this ) ; instruction = new QLabel ; instruction->setText( "Enter a number between 1 and 10 ! Numbers above 10 are decremented, below 0 incremented!" ) ; instruction->setWordWrap( true ) ; lowerPart = new QHBoxLayout ; entryField = new QLineEdit( "0" ) ; increment = new QPushButton( "Increment" ) ; decrement = new QPushButton( "Decrement" ) ; increment->setDefault( true ) ; connect( entryField , SIGNAL ( textChanged ( const QString & ) ) , this , SLOT ( buttonChange( const QString & )) ) ; connect( entryField , SIGNAL ( textEdited ( const QString & ) ) , this , SLOT ( buttonChange( const QString & )) ) ; connect( increment , SIGNAL ( clicked( ) ) , this , SLOT ( addField( ) )) ; connect( decrement , SIGNAL ( clicked( ) ) , this , SLOT ( subtractField( ))) ; lowerPart->addWidget( entryField ) ; lowerPart->addWidget( increment ) ; lowerPart->addWidget( decrement ) ; thisWidgetLayout->addWidget( instruction ) ; thisWidgetLayout->addLayout( lowerPart ) ; setLayout( thisWidgetLayout ) ; } void MyWidget::buttonChange( const QString & text ) { bool ok ; increment->setEnabled( text.toInt( &ok, 10 ) < 10 ) ; increment->setDisabled( text.toInt( &ok, 10 ) > 9 ) ; decrement->setEnabled( text.toInt( &ok, 10 ) > 0 ) ; decrement->setDisabled( text.toInt( &ok, 10 ) <= 0 ) ; if ( ! ( text == "0" ) ) entryField->setReadOnly( true ) ; } void MyWidget::addField( ) { bool ok ; int number = entryField->text( ).toInt( &ok , 10 ) ; number++ ; entryField->setText( QString("%1").arg( number )) ; } void MyWidget::subtractField( ) { bool ok ; int number = entryField->text( ).toInt( &ok , 10 ) ; number-- ; entryField->setText( QString("%1").arg( number )) ; } main.cpp
#include <QApplication> #include "task.h" int main( int argc, char *argv[ ] ) { QApplication app( argc , argv ) ; MyWidget theWidget ; theWidget.show( ) ; return app.exec( ) ; } type TForm1 = class(TForm) MaskEditValue: TMaskEdit; // Set Editmask on: "99;0; " SpeedButtonIncrement: TSpeedButton; SpeedButtonDecrement: TSpeedButton; procedure MaskEditValueChange(Sender: TObject); procedure SpeedButtonDecrementClick(Sender: TObject); procedure SpeedButtonIncrementClick(Sender: TObject); end; var Form1: TForm1; implementation procedure TForm1.MaskEditValueChange(Sender: TObject); begin TMaskEdit(Sender).Enabled := StrToIntDef(Trim(TMaskEdit(Sender).Text), 0) = 0; SpeedButtonIncrement.Enabled := StrToIntDef(Trim(TMaskEdit(Sender).Text), 0) < 10; SpeedButtonDecrement.Enabled := StrToIntDef(Trim(TMaskEdit(Sender).Text), 0) > 0; end; procedure TForm1.SpeedButtonDecrementClick(Sender: TObject); begin MaskEditValue.Text := IntToStr(Pred(StrToIntDef(Trim(MaskEditValue.Text), 0))); end; procedure TForm1.SpeedButtonIncrementClick(Sender: TObject); begin MaskEditValue.Text := IntToStr(Succ(StrToIntDef(Trim(MaskEditValue.Text), 0))); end; using fwt using gfx class Main { public static Void main () { Window { textField := Text { text = "0" } incButton := Button { text = "increment" onAction.add |Event e| { if (textField.text != "") { try { Int value := textField.text.toInt if (value < 10) value += 1 textField.text = value.toStr } catch {} } } } decButton := Button { text = "decrement" onAction.add |Event e| { if (textField.text != "") { try { Int value := textField.text.toInt if (value > 0) value -= 1 textField.text = value.toStr } catch {} } } } // add a listener for modifications to the text field // which updates the button visibilities textField.onModify.add |Event e| { try { Int value := textField.text.toInt incButton.enabled = (value < 10) // update whether button can be used decButton.enabled = (value > 0) // update whether button can be used } catch textField.text = "0" // reset if not an int } EdgePane { top = textField left = incButton right = decButton }, }.open } }#Include "windows.bi" Dim As HWND Window_Main, Edit_Number, Button_Inc, Button_Dec Dim As MSG msg Dim As Integer n Dim As String text 'Create a window with an input field and two buttons: Window_Main = CreateWindow("#32770", "GUI Enabling/Disabling of Controls", WS_OVERLAPPEDWINDOW Or WS_VISIBLE, 100, 100, 250, 200, 0, 0, 0, 0) Var Static_Number = CreateWindow("STATIC", "Value:", WS_VISIBLE Or WS_CHILD, 10, 10, 100, 20, Window_Main, 0, 0, 0) Edit_Number = CreateWindow("EDIT", "0", WS_BORDER Or WS_VISIBLE Or WS_CHILD Or ES_AUTOHSCROLL Or ES_Number, 110, 10, 100, 20, Window_Main, 0, 0, 0) Button_Inc = CreateWindow("BUTTON", "Increment", WS_VISIBLE Or WS_CHILD, 110, 40, 100, 20, Window_Main, 0, 0, 0) Button_Dec = CreateWindow("BUTTON", "Decrement", WS_VISIBLE Or WS_CHILD, 110, 70, 100, 20, Window_Main, 0, 0, 0) 'Windows message loop: While GetMessage(@msg, Window_Main, 0, 0) text = Space(GetWindowTextLength(Edit_Number) + 1)'Buffer for the text GetWindowText(Edit_Number, text, Len(text)) n = Val(text) If n <> 0 Then EnableWindow(Edit_Number, False) Else EnableWindow(Edit_Number, True) If n > 9 Then EnableWindow(Button_Inc, False) Else EnableWindow(Button_Inc, True) If n > 0 Then EnableWindow(Button_Dec, True) Else EnableWindow(Button_Dec, False) TranslateMessage(@msg) DispatchMessage(@msg) Select Case msg.hwnd Case Button_Inc 'Increment value: If msg.message = WM_LBUTTONDOWN Then SetWindowText(Edit_Number, Str(n + 1)) Case Button_Dec 'Decrement value: If msg.message = WM_LBUTTONDOWN Then SetWindowText(Edit_Number, Str(n - 1)) Case Window_Main If msg.message = WM_COMMAND Then End End Select Wend End var numberInput := displayNewElementIn('', 'body', 'input', false) var decButton := displayNewElementIn('Decrement', 'body', 'button', false) var incButton := displayNewElementIn('Increment', 'body', 'button', false) numberInput.value := 0 decButton.disabled := true incButton.disabled := true while true: parallel exitAfter 1 finished: if numberInput.value = 0: numberInput.disabled := false awaitDomeventBeep('change', numberInput) if not (0+1*numberInput.value = 0+1*numberInput.value): displayNewMessage('It was an invalid input !') numberInput.value := 0 else: numberInput.disabled := true awaitForever() if numberInput.value > 0: awaitClickBeep(decButton) numberInput.value := 1*numberInput.value - 1 else: awaitForever() if numberInput.value < 10: awaitClickBeep(incButton) numberInput.value := 1*numberInput.value + 1 else: awaitForever()_window = 1 begin enum 1 _inputFld _incBtn _decBtn end enum void local fn BuildWindow window _window, @"GUI enabling/disabling of controls", (0,0,350,150), NSWindowStyleMaskTitled textfield _inputFld,, @"0", (160,78,30,21) ControlSetAlignment( _inputFld, NSTextAlignmentCenter ) button _incBtn,,, @"Increment", (75,43,101,32) button _decBtn, NO,, @"Decrement", (174,43,101,32) end fn void local fn InputAction long value = fn ControlIntegerValue( _inputFld ) if ( value < 0 or value > 10 ) then value = 0 textfield _inputFld,, str(value) select ( value ) case 0 TextFieldSetEditable( _inputFld, YES ) button _incBtn, YES button _decBtn, NO case 10 TextFieldSetEditable( _inputFld, NO ) WindowMakeFirstResponder( _window, 0 ) button _incBtn, NO button _decBtn, YES case else TextFieldSetEditable( _inputFld, NO ) WindowMakeFirstResponder( _window, 0 ) button _incBtn, YES button _decBtn, YES end select end fn void local fn IncrementAction long value = fn ControlIntegerValue( _inputFld ) + 1 textfield _inputFld,, str(value) TextFieldSetEditable( _inputFld, NO ) WindowMakeFirstResponder( _window, 0 ) if ( value >= 10 ) then button _incBtn, NO if ( value > 0 ) then button _decBtn, YES end fn void local fn DecrementAction long value = fn ControlIntegerValue( _inputFld ) - 1 textfield _inputFld,, str(value) if ( value < 10 ) then button _incBtn, YES if ( value == 0 ) button _decBtn, NO TextFieldSetEditable( _inputFld, YES ) end if end fn void local fn DoDialog( ev as long, tag as long ) select ( ev ) case _btnClick select ( tag ) case _inputFld : fn InputAction case _incBtn : fn IncrementAction case _decBtn : fn DecrementAction end select end select end fn fn BuildWindow on dialog fn DoDialog HandleEventshValueBox As ValueBox 'We need a ValueBox hButton0 As Button 'We need a button hButton1 As Button 'We need another button Public Sub Form_Open() With Me 'Set the Form's Properties.. .height = 95 'Set the Height .Width = 350 'Set the Width .Arrangement = Arrange.Vertical 'Arrange items vertically .Padding = 5 'Border area .Title = "GUI enable/disable" 'Title displayed on the Form End With hValueBox = New ValueBox(Me) As "ValBox" 'Add a ValueBox to the Form as Event 'ValBox' With hValueBox 'Set the ValueBox's Properties.. .Expand = True 'Expand the ValueBox .Value = 0 'Set it's value to 0 End With hButton0 = New Button(Me) As "ButtonInc" 'Add a Button to the form as Event "ButtonInc" With hButton0 'Set the Button's Properties.. .Height = 28 'Set the Height .Text = "&Increment" 'Add Text (The '&' adds a keyboard shortcut) End With hButton1 = New Button(Me) As "ButtonDec" 'Add a Button to the form as Event "ButtonDec" With hButton1 'Set the Button's Properties.. .Height = 28 'Set the Height .Text = "&Decrement" 'Add Text (The '&' adds a keyboard shortcut) .Enabled = False 'Disable the button End With End Public Sub ButtonInc_Click() 'When the 'Increment' Button is clicked.. hValueBox.Value += 1 'Increase the Value in the ValueBox by 1 Checks End Public Sub ButtonDec_Click() 'When the 'Decrement' Button is clicked.. hValueBox.Value -= 1 'Increase the Value in the ValueBox by 1 Checks End Public Sub Checks() 'Checks the values to see which controls to en/disable If hValueBox.Value = 0 Then 'If the ValueBox = 0 then.. hValueBox.enabled = True 'Enable the control Else 'Else.. hValueBox.enabled = False 'Disable the control End If If hValueBox.Value > 9 Then 'If the ValueBox greater than 9 then.. hButton0.enabled = False 'Disable the control Else 'Else.. hButton0.enabled = True 'Enable the control End If If hValueBox.Value < 1 Then 'If the ValueBox less than 1 then.. hButton1.enabled = False 'Disable the control Else 'Else.. hButton1.enabled = True 'Enable the control End If End Public Sub ValBox_Leave() 'When the mouse leaves the ValueBox.. Checks 'Rune the Checks routine End Loosely based on the Vala entry.
package main import ( "github.com/gotk3/gotk3/gtk" "log" "math/rand" "strconv" "time" ) func validateInput(window *gtk.Window, str string) (int64, bool) { i, err := strconv.ParseInt(str, 10, 64) if err != nil { dialog := gtk.MessageDialogNew( window, gtk.DIALOG_MODAL, gtk.MESSAGE_ERROR, gtk.BUTTONS_OK, "Invalid value", ) dialog.Run() dialog.Destroy() return 0, false } return i, true } func check(err error, msg string) { if err != nil { log.Fatal(msg, err) } } func processState(i int64, entry *gtk.Entry, ib, db *gtk.Button) { if i == 0 { entry.SetSensitive(true) } else { entry.SetSensitive(false) } if i < 10 { ib.SetSensitive(true) } else { ib.SetSensitive(false) } if i > 0 { db.SetSensitive(true) } else { db.SetSensitive(false) } } func main() { rand.Seed(time.Now().UnixNano()) gtk.Init(nil) window, err := gtk.WindowNew(gtk.WINDOW_TOPLEVEL) check(err, "Unable to create window:") window.SetTitle("Rosetta Code") window.SetPosition(gtk.WIN_POS_CENTER) window.Connect("destroy", func() { gtk.MainQuit() }) box, err := gtk.BoxNew(gtk.ORIENTATION_HORIZONTAL, 1) check(err, "Unable to create box:") box.SetBorderWidth(1) label, err := gtk.LabelNew("Value:") check(err, "Unable to create label:") entry, err := gtk.EntryNew() check(err, "Unable to create entry:") entry.SetText("0") // initialize to zero entry.SetSensitive(true) // button to increment ib, err := gtk.ButtonNewWithLabel("Increment") check(err, "Unable to create increment button:") ib.SetSensitive(true) // button to decrement db, err := gtk.ButtonNewWithLabel("Decrement") check(err, "Unable to create decrement button:") db.SetSensitive(false) entry.Connect("activate", func() { // read and validate the entered value str, _ := entry.GetText() i, ok := validateInput(window, str) if !ok { entry.SetText("0") } processState(i, entry, ib, db) }) ib.Connect("clicked", func() { // read the entered value str, _ := entry.GetText() i, _ := validateInput(window, str) i++ entry.SetText(strconv.FormatInt(i, 10)) processState(i, entry, ib, db) }) db.Connect("clicked", func() { // read the entered value str, _ := entry.GetText() i, _ := validateInput(window, str) i-- entry.SetText(strconv.FormatInt(i, 10)) processState(i, entry, ib, db) }) box.PackStart(label, false, false, 2) box.PackStart(entry, false, false, 2) box.PackStart(ib, false, false, 2) box.PackStart(db, false, false, 2) window.Add(box) window.ShowAll() gtk.Main() } Icon and Unicon
This uses the Unicon specific graphics library.
import gui $include "guih.icn" class MessageDialog : Dialog (message) method component_setup () label := Label ("label="||message, "pos=20,20") add (label) button := TextButton("label=OK", "pos=100,60") button.connect (self, "dispose", ACTION_EVENT) add (button) connect (self, "dispose", CLOSE_BUTTON_EVENT) attrib ("size=200,100", "bg=light gray") end initially (message) self.Dialog.initially() self.message := message end class WindowApp : Dialog (button1, button2, field, value) method set_enabled () if value = 0 then field.clear_is_shaded () else field.set_is_shaded () if value <= 0 then button2.set_is_shaded () else button2.clear_is_shaded () if value >= 10 then button1.set_is_shaded () else button1.clear_is_shaded () end method increment () value +:= 1 field.set_contents (string(value)) set_enabled () end method decrement () value -:= 1 field.set_contents (string(value)) set_enabled () end method handle_text_field () if not(integer(field.get_contents ())) then { warning := MessageDialog ("Not a number") warning.show_modal () field.set_contents (string(value)) } else { n := integer (field.get_contents ()) if not (0 <= n <= 10) then { warning := MessageDialog ("Not in range") warning.show_modal () field.set_contents (string(value)) } } value := integer (field.get_contents ()) # must be ok set_enabled () end method component_setup () value := 0 field := TextField("contents="||value, "pos=20,20", "size=150") field.connect (self, "handle_text_field", TEXTFIELD_CHANGED_EVENT) add (field) button1 := TextButton("label=Increment", "pos=20,60", "size=70") button1.connect (self, "increment", ACTION_EVENT) add (button1) button2 := TextButton("label=Decrement", "pos=100,60", "size=70") button2.connect (self, "decrement", ACTION_EVENT) add (button2) connect (self, "dispose", CLOSE_BUTTON_EVENT) attrib ("size=200,100", "bg=light gray") set_enabled () end end procedure main () w := WindowApp () w.show_modal () end J 8.x
task_run=: wd bind (noun define) pc task nosize; cc decrement button;cn "Decrement"; cc increment button;cn "Increment"; cc Value edit center;set Value text 0; set decrement enable 0; pas 6 6;pcenter; pshow; ) task_cancel=: task_close=: wd bind 'pclose' task_Value_button=: update=: verb define wd 'set Value text ', ": n=. {. 0 ". Value wd 'set Value enable ', ": n=0 wd 'set increment enable ', ": n<10 wd 'set decrement enable ', ": n>0 ) task_increment_button=:verb define update Value=: ": 1 + 0 ". Value ) task_decrement_button=:verb define update Value=: ": _1 + 0 ". Value ) J 6.x
task_run=: wd bind (noun define) pc task nosize; xywh 6 30 48 12;cc decrement button;cn "-"; xywh 6 18 48 12;cc increment button;cn "+"; xywh 6 6 48 12;cc Value edit; set Value 0; pas 6 6;pcenter; pshow; ) task_close=: wd bind 'pclose' task_Value_button=: update=: verb define wd 'set Value ', ": n=. {. 0 ". Value wd 'setenable Value ', ": n=0 wd 'setenable increment ', ": n<10 wd 'setenable decrement ', ": n>0 ) task_increment_button=:verb define update Value=: ": 1 + 0 ". Value ) task_decrement_button=:verb define update Value=: ": _1 + 0 ". Value ) Example use:
task_run'' import java.awt.GridLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.KeyEvent; import java.awt.event.KeyListener; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JTextField; import javax.swing.SwingUtilities; public class Interact extends JFrame{ final JTextField numberField; final JButton incButton, decButton; public Interact(){ //stop the GUI threads when the user hits the X button setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); numberField = new JTextField(); incButton = new JButton("Increment"); decButton = new JButton("Decrement"); numberField.setText("0");//start at 0 decButton.setEnabled(false);//we're already at 0 //listen for button presses in the text field numberField.addKeyListener(new KeyListener(){ @Override public void keyTyped(KeyEvent e) { //if the entered character is not a digit if(!Character.isDigit(e.getKeyChar())){ //eat the event (i.e. stop it from being processed) e.consume(); }else if(Character.isDigit(e.getKeyChar())){ //This method is executed from the event thread and updating the GUI //from there doesn't always work. invokeLater will ensure that the //GUI is updated SwingUtilities.invokeLater(new Runnable() { @Override public void run() { String text = numberField.getText(); if(text.isEmpty()){//default to 0 when all text is erased numberField.setText("0"); decButton.setEnabled(false); incButton.setEnabled(true); return; } if(Long.valueOf(text) <= 0){ decButton.setEnabled(false); incButton.setEnabled(true); }else if(Long.valueOf(text) >= 10){ incButton.setEnabled(false); decButton.setEnabled(true); }else{ incButton.setEnabled(true); decButton.setEnabled(true); } } }); } } @Override public void keyReleased(KeyEvent e){} @Override public void keyPressed(KeyEvent e){ //backspace and delete don't register in keyTyped because they don't //display a Unicode character, so they must be handled here if(e.getKeyCode() == KeyEvent.VK_BACK_SPACE || e.getKeyCode() == KeyEvent.VK_DELETE){ SwingUtilities.invokeLater(new Runnable() { @Override public void run() { String text = numberField.getText(); if(text.isEmpty()){ numberField.setText("0"); decButton.setEnabled(false); incButton.setEnabled(true); return; } if(Long.valueOf(text) <= 0){ decButton.setEnabled(false); incButton.setEnabled(true); }else if(Long.valueOf(text) >= 10){ incButton.setEnabled(false); decButton.setEnabled(true); }else{ incButton.setEnabled(true); decButton.setEnabled(true); } } }); } } }); //listen for button clicks on the increment button incButton.addActionListener(new ActionListener(){ @Override public void actionPerformed(ActionEvent e) { String text = numberField.getText(); numberField.setText((Long.valueOf(text) + 1) + ""); if(Long.valueOf(text) + 1 >= 10){ incButton.setEnabled(false); } if(Long.valueOf(text) + 1 > 0){ decButton.setEnabled(true); } } }); //listen for button clicks on the random button decButton.addActionListener(new ActionListener(){ @Override public void actionPerformed(ActionEvent e) { String text = numberField.getText(); numberField.setText((Long.valueOf(text) - 1) + ""); if(Long.valueOf(text) - 1 <= 0){ decButton.setEnabled(false); } if(Long.valueOf(text) - 1 < 10){ incButton.setEnabled(true); } } }); //arrange the components in a grid with 2 rows and 1 column setLayout(new GridLayout(2, 1)); //a secondary panel for arranging both buttons in one grid space in the window JPanel buttonPanel = new JPanel(); //the buttons are in a grid with 1 row and 2 columns buttonPanel.setLayout(new GridLayout(1, 2)); //add the buttons buttonPanel.add(incButton); buttonPanel.add(decButton); //put the number field on top of the buttons add(numberField); add(buttonPanel); //size the window appropriately pack(); } public static void main(String[] args){ new Interact().setVisible(true); } }
import javafx.application.Application; import javafx.beans.property.LongProperty; import javafx.beans.property.SimpleLongProperty; import javafx.scene.Scene; import javafx.scene.control.Button; import javafx.scene.control.TextField; import javafx.scene.layout.HBox; import javafx.scene.layout.VBox; import javafx.stage.Stage; import javafx.util.converter.NumberStringConverter; public class InteractFX extends Application { public static void main(String[] args) { launch(args); } @Override public void start(Stage stage) throws Exception { TextField input = new TextField("0"){ // only accept numbers as input @Override public void replaceText(int start, int end, String text) { if (text.matches("[0-9]*")) { super.replaceText(start, end, text); } } // only accept numbers on copy+paste @Override public void replaceSelection(String text) { if (text.matches("[0-9]*")) { super.replaceSelection(text); } } }; // when the textfield is empty, replace text with "0" input.textProperty().addListener((observable, oldValue, newValue)->{ if(newValue == null || newValue.trim().isEmpty()){ input.setText("0"); } }); // get a bi-directional bound long-property of the input value LongProperty inputValue = new SimpleLongProperty(); input.textProperty().bindBidirectional(inputValue, new NumberStringConverter()); // textfield is disabled when the current value is other than "0" input.disableProperty().bind(inputValue.isNotEqualTo(0)); Button increment = new Button("Increment"); increment.setOnAction(event-> inputValue.set(inputValue.get() + 1)); // incr-button is disabled when input is >= 10 increment.disableProperty().bind(inputValue.greaterThanOrEqualTo(10)); Button decrement = new Button("Decrement"); decrement.setOnAction(event-> inputValue.set(inputValue.get() - 1)); // decrement button is disabled when input is <=0 decrement.disableProperty().bind(inputValue.lessThanOrEqualTo(0)); // layout VBox root = new VBox(); root.getChildren().add(input); HBox buttons = new HBox(); buttons.getChildren().addAll(increment,decrement); root.getChildren().add(buttons); stage.setScene(new Scene(root)); stage.sizeToScene(); stage.show(); } } using Tk w = Toplevel("GUI enabling/disabling") fr = Frame(w) pack(fr, {:expand=>true, :fill => "both"}) value = Entry(fr) increment = Button(fr, "+") decrement = Button(fr, "-") formlayout(value, "Value:") formlayout(increment, " ") formlayout(decrement, " ") ## value stores a string set_value(value, "0") ## The field is initialized to zero. get(value::Tk_Entry) = try parseint(get_value(value)) catch e nothing end function update() cur_value = get(value) set_enabled(value, isa(cur_value, Integer) && cur_value == 0) set_enabled(increment, isa(cur_value, Integer) && cur_value < 10) set_enabled(decrement, isa(cur_value, Integer) && cur_value > 0) end crement = function(step) set_enabled(value, true) set_value(value, string(get(value) + step)) update() end tk_bind(increment, "command", path -> crement(1)) tk_bind(decrement, "command", path -> crement(-1)) update() function validate_command(path, P) try if length(P) > 0 parseint(P); update() end tcl("expr", "TRUE") catch e tcl("expr", "FALSE") end end function invalid_command(path, W) println("Invalid value") tcl(W, "delete", "@0", "end") end tk_configure(value, {:validate=>"focusout", :validatecommand=>validate_command, :invalidcommand=>invalid_command }) // version 1.2.21 import javafx.application.Application import javafx.beans.property.SimpleLongProperty import javafx.scene.Scene import javafx.scene.control.Button import javafx.scene.control.TextField import javafx.scene.layout.HBox import javafx.scene.layout.VBox import javafx.stage.Stage import javafx.util.converter.NumberStringConverter import javafx.event.ActionEvent val digits = Regex("[0-9]*") class InteractFX : Application() { override fun start(stage: Stage) { val input = object : TextField("0") { // only accept numbers as input override fun replaceText(start: Int, end: Int, text: String) { if (text.matches(digits)) super.replaceText(start, end, text) } // only accept numbers on copy + paste override fun replaceSelection(text: String) { if (text.matches(digits)) super.replaceSelection(text) } } // when the textfield is empty, replace text with "0" input.textProperty().addListener { _, _, newValue -> if (newValue == null || newValue.trim().isEmpty()) input.text = "0" } // get a bi-directional bound long-property of the input value val inputValue = SimpleLongProperty() input.textProperty().bindBidirectional(inputValue, NumberStringConverter()) // textfield is disabled when the current value is other than "0" input.disableProperty().bind(inputValue.isNotEqualTo(0)) val increment = Button("Increment") increment.addEventHandler(ActionEvent.ACTION) { inputValue.set(inputValue.get() + 1) } // increment button is disabled when input is >= 10 increment.disableProperty().bind(inputValue.greaterThanOrEqualTo(10)) val decrement = Button("Decrement") decrement.addEventHandler(ActionEvent.ACTION) { inputValue.set(inputValue.get() - 1) } // decrement button is disabled when input is <= 0 decrement.disableProperty().bind(inputValue.lessThanOrEqualTo(0)) // layout val root = VBox() root.children.add(input) val buttons = HBox() buttons.children.addAll(increment, decrement) root.children.add(buttons) stage.scene = Scene(root) stage.sizeToScene() stage.show() } } fun main(args: Array<String>) { Application.launch(InteractFX::class.java, *args) } nomainwin textbox #demo.val, 20, 50, 90, 24 button #demo.dec, "Decrement", [btnDecrement], UL, 20, 90, 90, 24 button #demo.inc, "Increment", [btnIncrement], UL, 20, 120, 90, 24 statictext #demo.txt, "Positive or negative whole numbers only.", 20, 170, 240, 24 open "Rosetta Task: GUI enabling/disabling of controls" for window as #demo #demo "trapclose [quit]" #demo.val 0 #demo.dec "!disable" wait [quit] close #demo end [btnDecrement] validNum = validNum() if validNum = 0 then #demo.val "!contents? nVal$" notice nVal$;" does not appear to be a valid whole number." else #demo.val "!contents? nVal" if nVal > 0 then nVal = nVal - 1 end if end if #demo.val nVal call disEnableControls nVal wait [btnIncrement] validNum = validNum() if validNum = 0 then #demo.val "!contents? nVal$" notice nVal$;" does not appear to be a valid whole number." else #demo.val "!contents? nVal" if nVal < 10 then nVal = nVal + 1 end if end if #demo.val nVal call disEnableControls nVal wait Function validNum() validNum$ = "0123456789" #demo.val "!contents? nVal$" nVal$ = trim$(nVal$) if left$(nVal$, 1) = "-" then neg = 1 nVal$ = mid$(nVal$, 2) else neg = 0 end if validNum = 1 for i = 1 to len(nVal$) if instr(validNum$, mid$(nVal$, i, 1)) = 0 then validNum = 0 end if next i End Function Sub disEnableControls nVal if nVal > 9 then #demo.inc "!disable" else #demo.inc "!enable" end if if nVal < 1 then #demo.dec "!disable" else #demo.dec "!enable" end if if nVal = 0 then #demo.val "!enable" else #demo.val "!disable" end if End SubIn LiveCode, GUIs are expected to be designed using the IDE, with the developer writing scripts to handle messages that are passed by the LC Engine. It is certainly possible to dynamically create windows (stacks) and all the various controls, however it is somewhat antithetical to the LC approach of rapid development.
1. Create a new mainstack
2. Draw on two buttons
2.1 The first button name is "Button1", with a label of "Increment"
2.2 The second button name is "Button2", with a label of "Decrement"
3. Draw a text field and name it "Field1", enter 0 as its content.
4. Select Object->Card Script and enter the following to handle enabling the buttons.
command enableButtons v switch case v <= 0 put 0 into fld "Field1" set the enabled of btn "Button1" to true set the enabled of btn "Button2" to false break case v >= 10 put 10 into fld "Field1" set the enabled of btn "Button1" to false set the enabled of btn "Button2" to true break default set the enabled of btn "Button1" to true set the enabled of btn "Button2" to true put v into fld "Field1" end switch end enableButtonsFor the increment button, click on Button 1 (in edit mode) and the select "code" from the toolbar and enter the following to handle clicks
on mouseUp put field "Field1" into x add 1 to x enableButtons x end mouseUpRepeat for Button 2 (note we are subtracting here)
on mouseUp put field "Field1" into x subtract 1 from x enableButtons x end mouseUpFinally add the code to handle keyboard entry in text field's code. Note this code prevents entering digits outside 0-9 and limits the value between 0 and 10.
on rawKeyDown k if numToChar(k) is among the items of "1,2,3,4,5,6,7,8,9,0" then if (numToChar(k) + the text of me) <= 10 then enableButtons (numToChar(k) + the text of me) end if else if k = 65288 then pass rawKeyDown end if end rawKeyDownSwitch back to the form, and enter run mode to execute.
n.b. Open stack handlers would be prudent to initialise the default value and button states if this were to be saved for standalone execution.
Normally a function can't call other except something global or something defined in function (local), or for member functions in Group object, they can call other members public or private at same level or deeper but then only the public members. Using Call Local we call functions like function's part. When an event service function called (by event), interpreter provide the same name as the module's name, where form declared, so this call is a "local call". So a second local call inside event service function,also provide same name. So global local1 called as local, so code executed as part of CheckIt (but without same "current" stack, and other specific to execution object properties). Modules, functions, threads, events are all executed on "execution objects" which carries the execution code.
\\ this is global, but call as local in events, which means with local visibility for identifiers \\ so thispos and this$ has to exist in caller 's context Function Global Local1(new Feed$) { \\ this function can be used from other Integer \\ this$ and thispos, exist just before the call of this function local sgn$ if feed$="" and this$="-" then thispos-- : exit if left$(this$,1)="-" then sgn$="-": this$=mid$(this$, 2) if this$<>Trim$(this$) then this$=Feed$ : thispos-- : exit If Trim$(this$)="" then this$="0" : thispos=2 : exit if instr(this$,"+")>0 and sgn$="-" then this$=filter$(this$, "+") : sgn$="" if instr(this$,"-")>0 and sgn$="" then this$=filter$(this$, "-") : sgn$="-" if filter$(this$,"0123456789")<>"" then this$=Feed$ : thispos-- : exit if len(this$)>1 then While left$(this$,1)="0" {this$=mid$(this$, 2)} this$=sgn$+this$ if this$="-0" then this$="-" : thispos=2 } Module CheckIt { Declare form1 form Declare textbox1 textbox form form1 Declare buttonInc Button form form1 Declare buttonDec Button form form1 Method textbox1, "move", 2000,2000,4000,600 Method buttonInc, "move", 2000,3000,2000,600 Method buttonDec, "move", 4000,3000,2000,600 With textbox1,"vartext" as textbox1.value$, "Prompt", "Value:" ', "ShowAlways", True With buttonInc,"Caption","Increment" With buttonDec,"Caption","Decrement","Locked", True textbox1.value$="0" Function controlIncDec(what$){ With buttonInc, "locked", not val(what$)<10 With buttonDec, "locked", not val(what$)>0 } finishEnter=false Function TextBox1.ValidString { \\ this function called direct from textbox Read New &this$, &thispos Call Local local1(textbox1.value$) Call Local controlIncDec(this$) } Function TextBox1.Enable { With TextBox1, "Enabled", true finishEnter=false } Function TextBox1.Disable { With TextBox1, "Enabled", false finishEnter=true } Function TextBox1.Enter { Call Local TextBox1.Disable() } Function buttonInc.Click { if not finishEnter then Call Local TextBox1.Disable() textbox1.value$=str$(val(textbox1.value$)+1, "") if val(textbox1.value$)=0 then Call Local TextBox1.Enable() } function buttonDec.Click { if not finishEnter then Call Local TextBox1.Disable() textbox1.value$=str$(val(textbox1.value$)-1, "") if val(textbox1.value$)=0 then Call Local TextBox1.Enable() } Call Local controlIncDec(textBox1.Value$) Method form1, "show", 1 Declare form1 nothing } CheckitFor this problem, you will need to open up Maple, go to the Components tab on the left, and insert a Text Area, and 2 Buttons. By right clicking each button, and clicking Component Properties, change one to Increase, and the other to Decrease. Then, click on 'Edit Content Changed Action". In the one labeled increase, type:
Increase(); In the one labeled Decrease, type:
Decrease(); Then, by clicking the 2 gears and opening up the start-up commands, enter this:
macro(SP=DocumentTools:-SetProperty, GP=DocumentTools:-GetProperty); with(Maplets[Elements]): SP("Text",value,0); Increase:=proc() SP("Text",value,parse(GP("Text",value))+1); if parse(GP("Text",value))>=10 then SP("Button0", enabled, false); else SP("Button0", enabled, true); end if; if parse(GP("Text",value))<=0 then SP("Button1", enabled, false); else SP("Button1", enabled, true); end if; end proc; Decrease:=proc() SP("Text",value,parse(GP("Text",value))-1); if parse(GP("Text",value))<=0 then SP("Button1", enabled, false); else SP("Button1", enabled, true); end if; if parse(GP("Text",value))>=10 then SP("Button0", enabled, false); else SP("Button0", enabled, true); end if; end proc; Manipulate[Null, {{value, 0}, InputField[Dynamic[value], Number, Enabled -> Dynamic[value == 0]] &}, Row@{Button["increment", value++, Enabled -> Dynamic[value < 10]], Button["decrement", value--, Enabled -> Dynamic[value > 0]]}] ; file: gui-enable.lsp ; url: http://rosettacode.org/wiki/GUI_enabling/disabling_of_controls ; author: oofoe 2012-02-02 ; Load library and initialize GUI server: (load (append (env "NEWLISPDIR") "/guiserver.lsp")) (gs:init) ; The "interlock" function maintains GUI consistency by disabling all ; controls, then selectively re-enabling them depending on the value ; in the textbox. (define (interlock) (gs:disable 'value 'increment 'decrement) (let ((v (int (gs:get-text 'value)))) (if (= 0 v) (gs:enable 'value)) (if (< v 10) (gs:enable 'increment)) (if (< 0 v) (gs:enable 'decrement)) )) ; Callbacks. (define (update f) (gs:set-text 'value (string (f (int (gs:get-text 'value)) 1))) (interlock)) (define (incrementing id) (update +)) (define (decrementing id) (update -)) (define (valuing id) (interlock)) ; Create main window frame and set layout direction. (gs:frame 'main 100 100 200 75 "GUI Enable") (gs:set-flow-layout 'main "center" 4 4) ; Create and add widgets. (gs:button 'decrement 'decrementing "-" 30) (gs:text-field 'value 'valuing 8) (gs:set-text 'value "0") (gs:button 'increment 'incrementing "+" 30) (gs:add-to 'main 'decrement 'value 'increment) ; Show main window. (gs:set-visible 'main true) ; Start event loop. (gs:listen) (exit) Screenshot:
Using Gtk2
import gtk2, strutils, glib2 var valu: int = 0 proc thisDestroy(widget: PWidget, data: Pgpointer){.cdecl.} = main_quit() nim_init() var window = window_new(gtk2.WINDOW_TOPLEVEL) var content = vbox_new(true,10) var hbox1 = hbox_new(true,10) var entry_fld = entry_new() entry_fld.set_text("0") var btn_quit = button_new("Quit") var btn_inc = button_new("Increment") var btn_dec = button_new("Decrement") add(hbox1,btn_inc) add(hbox1,btn_dec) pack_start(content, entry_fld, true, true, 0) pack_start(content, hbox1, true, true, 0) pack_start(content, btn_quit, true, true, 0) set_border_width(window, 5) add(window, content) proc thisCheckBtns = set_sensitive(btn_inc, valu < 10) set_sensitive(btn_dec, valu > 0) set_sensitive(entry_fld, valu == 0) proc thisInc(widget: PWidget, data: Pgpointer){.cdecl.} = inc(valu) entry_fld.set_text($valu) thisCheckBtns() proc thisDec(widget: PWidget, data: Pgpointer){.cdecl.} = dec(valu) entry_fld.set_text($valu) thisCheckBtns() proc thisTextChanged(widget: PWidget, data: Pgpointer) {.cdecl.} = try: valu = parseInt($entry_fld.get_text()) except ValueError: entry_fld.set_text($valu) thisCheckBtns() discard signal_connect(window, "destroy", SIGNAL_FUNC(thisDestroy), nil) discard signal_connect(btn_quit, "clicked", SIGNAL_FUNC(thisDestroy), nil) discard signal_connect(btn_inc, "clicked", SIGNAL_FUNC(thisInc), nil) discard signal_connect(btn_dec, "clicked", SIGNAL_FUNC(thisDec), nil) discard signal_connect(entry_fld, "changed", SIGNAL_FUNC(thisTextChanged), nil) show_all(window) thisCheckBtns() main() Using Gtk3 (gintro)
Note that this example no longer works with versions of Nim compiler greater or equal to 2.0.
import strutils import gintro/[glib, gobject, gtk, gio] type Context = ref object value: int entry: Entry btnIncr: Button btnDecr: Button #--------------------------------------------------------------------------------------------------- proc checkButtons(ctx: Context) = ctx.btnIncr.setSensitive(ctx.value < 10) ctx.btnDecr.setSensitive(ctx.value > 0) ctx.entry.setSensitive(ctx.value == 0) #--------------------------------------------------------------------------------------------------- proc onQuit(button: Button; window: ApplicationWindow) = window.destroy() #--------------------------------------------------------------------------------------------------- proc onIncr(button: Button; ctx: Context) = inc ctx.value ctx.entry.setText($ctx.value) ctx.checkButtons() #--------------------------------------------------------------------------------------------------- proc onDecr(button: Button; ctx: Context) = dec ctx.value ctx.entry.setText($ctx.value) ctx.checkButtons() #--------------------------------------------------------------------------------------------------- proc onEntryChange(entry: Entry; ctx: Context) = try: ctx.value = entry.text().parseInt() except ValueError: entry.setText($ctx.value) #--------------------------------------------------------------------------------------------------- proc activate(app: Application) = ## Activate the application. let window = app.newApplicationWindow() window.setTitle("GUI controls") let content = newBox(Orientation.vertical, 10) content.setHomogeneous(true) let hbox1 = newBox(Orientation.horizontal, 10) hbox1.setHomogeneous(true) let hbox2 = newBox(Orientation.horizontal, 1) hbox2.setHomogeneous(false) let label = newLabel("Value:") let entry = newEntry() entry.setText("0") let btnQuit = newButton("Quit") let btnIncr = newButton("Increment") let btnDecr = newButton("Decrement") hbox2.add(label) hbox2.add(entry) hbox1.add(btnIncr) hbox1.add(btnDecr) content.packStart(hbox2, true, true, 0) content.packStart(hbox1, true, true, 0) content.packStart(btnQuit, true, true, 0) window.setBorderWidth(5) window.add(content) let context = Context(value: 0, entry: entry, btnIncr: btnIncr, btnDecr: btnDecr) discard btnQuit.connect("clicked", onQuit, window) discard btnIncr.connect("clicked", onIncr, context) discard btnDecr.connect("clicked", onDecr, context) discard entry.connect("changed", onEntryChange, context) context.checkButtons() window.showAll() #——————————————————————————————————————————————————————————————————————————————————————————————————— let app = newApplication(Application, "Rosetta.GuiControls") discard app.connect("activate", activate) discard app.run() Using IUP
import iup, strutils, math # assumes you have the iup .dll or .so installed randomize() discard iup.open(nil,nil) var lbl = Label("Value:") setAttribute(lbl,"PADDING","2x2") var valu = Text(nil) SetAtt(nil, valu, "PADDING", "2x2", "VALUE", "0", nil) var txtBox = Hbox(lbl, valu, nil) SetAttribute(txtBox, "MARGIN", "10x10") var incBtn = Button("+1", "") var decBtn = Button("-1", "") SetAttribute(incBtn,"RASTERSIZE","25x25") SetAttribute(decBtn,"RASTERSIZE","25x25") var btnBox = Vbox(incBtn, decBtn, nil) SetAttribute(btnBox, "MARGIN", "5x5") proc toCB(fp: proc): ICallback = return cast[ICallback](fp) proc setValuState(value: int) = if value == 0: SetAttribute(valu, "ACTIVE", $(true)) else: SetAttribute(valu, "ACTIVE", $(false)) proc setBtnsState(value: int) = if value <= 0: SetAttribute(decBtn,"ACTIVE", $(false)) SetAtt(nil, incBtn,"ACTIVE", $(true), "FOCUS", $(true), nil) elif value >= 10: SetAttribute(incBtn,"ACTIVE", $(false)) SetAtt(nil, decBtn,"ACTIVE", $(true), "FOCUS", $(true), nil) else: SetAttribute(decBtn,"ACTIVE", $(true)) SetAttribute(incBtn,"ACTIVE", $(true)) # Click handler for Click button proc incClick(ih:PIhandle): cint {.cdecl.} = var s: string = $(GetAttribute(valu,"VALUE")) var x: int = 0 try: x = 1 + parseInt(s) except: x = 1 # default to 1 if non-numeric entry setAttribute(valu,"VALUE", $x) setValuState(x) setBtnsState(x) return IUP_DEFAULT # Click handler for Decrement button proc decClick(ih:PIhandle): cint {.cdecl.} = var s: string = $(GetAttribute(valu,"VALUE")) var x: int = 0 try: x = -1 + parseInt(s) except: x = 1 # default to 1 if non-numeric entry setAttribute(valu,"VALUE", $x) setValuState(x) setBtnsState(x) return IUP_DEFAULT # Key handler to check for Esc pressed proc key_cb(ih:PIhandle, c: cint):cint {.cdecl.} = #echo c if (c == Iup.K_esc) and (Iup.Alarm("Exit?", "Had enough?","Yes","Keep going",nil) == 1): return IUP_CLOSE # Exit application return IUP_CONTINUE var contents = Hbox(txtBox, btnBox, nil) SetAttribute(contents, "MARGIN", "5x5") discard setCallback(incBtn,"ACTION", toCB(incClick)) discard setCallback(decBtn,"ACTION", toCB(decClick)) discard setCallback(contents,"K_ANY", toCB(key_cb)) var dlg = Dialog(contents) SetAtt(nil, dlg, "TITLE","GUI Interaction", "SIZE","200x75", nil) discard dlg.show() discard mainloop() iup.close() #!/usr/bin/perl use strict; use warnings; use Tk; use Tk::Dialog; use Tk::LabFrame; my $value = 0; my $mw = MainWindow->new; $mw->title( 'GUI component enable/disable' ); my $lf = $mw->LabFrame( -label => 'Value' )->pack(-fill => 'x',-expand => 1); my $entry = $lf->Entry( -width => 10, -textvariable => \$value, -validate => 'key', -validatecommand => sub { $_[0] =~ /^\d{1,9}\z/ ? do{setenable($_[0]); 1} : 0 }, )->pack(-fill => 'x', -expand => 1); my $inc = $mw->Button( -text => 'increment', -command => sub { $value++; setenable($value) }, )->pack( -side => 'left' ); my $dec = $mw->Button( -text => 'decrement', -command => sub { $value--; setenable($value) }, )->pack( -side => 'right' ); setenable($value); MainLoop; sub setenable { $inc and $inc->configure( -state => $_[0] < 10 ? 'normal' : 'disabled' ); $dec and $dec->configure( -state => $_[0] > 0 ? 'normal' : 'disabled' ); $entry and $entry->configure( -state => $_[0] == 0 ? 'normal' : 'disabled' ); } Note: this validates each input char separately, and '-' is not "NUMBER": the only way to get numbers <0 or >9 into the input field is to paste them.
include pGUI.e Ihandle txt, inc, dec, hbx, vbx, dlg function activate(integer v) IupSetInt(txt,"VALUE",v) IupSetAttribute(inc,"ACTIVE",iff(v<10,"YES":"NO")) IupSetAttribute(dec,"ACTIVE",iff(v>0,"YES":"NO")) IupSetAttribute(txt,"ACTIVE",iff(v=0,"YES":"NO")) return IUP_CONTINUE end function function valuechanged_cb(Ihandle /*ih*/) return activate(IupGetInt(txt,"VALUE")) end function function inc_cb(Ihandle /*ih*/) return activate(IupGetInt(txt,"VALUE")+1) end function function dec_cb(Ihandle /*ih*/) return activate(IupGetInt(txt,"VALUE")-1) end function function esc_close(Ihandle /*ih*/, atom c) return iff(c=K_ESC?IUP_CLOSE:IUP_CONTINUE) end function IupOpen() txt = IupText("VALUECHANGED_CB",Icallback("valuechanged_cb"),"FILTER=NUMBER, EXPAND=YES") inc = IupButton("increment",Icallback("inc_cb")) dec = IupButton("decrement",Icallback("dec_cb"),"ACTIVE=NO") hbx = IupHbox({inc,dec},"MARGIN=0x10, GAP=20") vbx = IupVbox({txt,hbx},"MARGIN=40x20") dlg = IupDialog(vbx) IupSetCallback(dlg, "K_ANY", Icallback("esc_close")) IupShow(dlg) if platform()!=JS then IupMainLoop() IupClose() end if
The standard PicoLisp GUI is HTTP based. Connect your browser to http://localhost:8080 after starting the following script.
#!/usr/bin/picolisp /usr/lib/picolisp/lib.l (load "@ext.l" "@lib/http.l" "@lib/xhtml.l" "@lib/form.l") (de start () (and (app) (zero *Number)) (action (html 0 "Enable/Disable" "@lib.css" NIL (form NIL (gui '(+Var +Able +NumField) '*Number '(=0 *Number) 20 "Value") (gui '(+Able +JS +Button) '(> 10 *Number) "increment" '(inc '*Number) ) (gui '(+Able +JS +Button) '(gt0 *Number) "decrement" '(dec '*Number) ) ) ) ) ) (server 8080 "!start") (wait)Works with SWI-Prolog and XPCE.
dialog('GUI_Interaction', [ object := GUI_Interaction, parts := [ GUI_Interaction := dialog('Rosetta Code'), Name := label(name, 'Value :'), Input_field := text_item(input_field, '0'), Increment := button(increment), Decrement := button(decrement) ], modifications := [ Input_field := [ label := 'Value :', length := 28, show_label := @off ], Decrement := [active := @off] ], layout := [ area(Name, area(50, 26, 25, 24)), area(Input_field, area(95, 24, 200, 24)), area(Increment, area(50, 90, 80, 24)), area(Decrement, area(230, 90, 80, 24)) ], behaviour := [ Increment := [ message := message(@prolog, increment, Increment, Decrement, Input_field ) ], Decrement := [ message := message(@prolog, decrement, Increment, Decrement, Input_field) ], Input_field := [ message := message(@prolog, input, Increment, Decrement, @receiver, @arg1) ] ] ]). gui_component :- make_dialog(S, 'GUI_Interaction'), send(S, open). increment(Incr, Decr, Input) :- get(Input, selection, V), atom_number(V, Val), Val1 is Val + 1, send(Input, selection, Val1), test(Val1, Incr, Decr, Input). decrement(Incr, Decr, Input) :- get(Input, selection, V), atom_number(V, Val), Val1 is Val - 1, send(Input, selection, Val1), test(Val1, Incr, Decr, Input). input(Incr, Decr, Input, Selection) :- catch( (term_to_atom(T, Selection), number(T)), _, ( send(@display, inform, 'Please type a number !'), T = 0, send(Input,selection, T))), test(T, Incr, Decr, Input). test(V, Incr, Decr, Input) :- ( V = 0 -> send(Input, active, @on); send(Input, active, @off)), send(Incr, active, @on), send(Decr, active, @on), ( V < 1 -> send(Decr, active, @off) ; V > 9 -> send(Incr, active, @off)). Enumeration #TextGadget #AddButton #SubButton EndEnumeration Procedure UpdateGadgets(Value,UpdateValue=0) Overmax=0: UnderMin=0 If Value>=10 Overmax=1 ElseIf Value<=0 UnderMin=1 EndIf DisableGadget(#AddButton,Overmax) DisableGadget(#SubButton,UnderMin) If UpdateValue SetGadgetText(#TextGadget,Str(Value)) EndIf EndProcedure If OpenWindow(0,#PB_Ignore,#PB_Ignore,110,70,"PB-GUI",#PB_Window_SystemMenu) StringGadget(#TextGadget,10,10,90,20,"") ButtonGadget(#AddButton,10,40,30,20,"+") ButtonGadget(#SubButton,70,40,30,20,"-") UpdateGadgets(Value,1) Repeat Event=WaitWindowEvent() If Event=#PB_Event_Gadget Gadget=EventGadget() Select Gadget Case #AddButton Value+1 UpdateGadgets(Value,1) Case #SubButton Value-1 UpdateGadgets(Value,1) Default EType=EventType() If EType=#PB_EventType_Change Value=Val(GetGadgetText(#TextGadget)) UpdateGadgets(Value) EndIf EndSelect EndIf Until Event=#PB_Event_CloseWindow EndIf #!/usr/bin/env python3 import tkinter as tk class MyForm(tk.Frame): def __init__(self, master=None): tk.Frame.__init__(self, master) self.pack(expand=True, fill="both", padx=10, pady=10) self.master.title("Controls") self.setupUI() def setupUI(self): self.value_entry = tk.Entry(self, justify=tk.CENTER) self.value_entry.grid(row=0, column=0, columnspan=2, padx=5, pady=5, sticky="nesw") self.value_entry.insert('end', '0') self.value_entry.bind("<KeyPress-Return>", self.eventHandler) self.decre_btn = tk.Button(self, text="Decrement", state=tk.DISABLED) self.decre_btn.grid(row=1, column=0, padx=5, pady=5) self.decre_btn.bind("<Button-1>", self.eventHandler) self.incre_btn = tk.Button(self, text="Increment") self.incre_btn.grid(row=1, column=1, padx=5, pady=5) self.incre_btn.bind("<Button-1>", self.eventHandler) def eventHandler(self, event): value = int(self.value_entry.get()) if event.widget == self.value_entry: if value > 10: self.value_entry.delete("0", "end") self.value_entry.insert("end", "0") elif value == 10: self.value_entry.config(state=tk.DISABLED) self.incre_btn.config(state=tk.DISABLED) self.decre_btn.config(state=tk.NORMAL) elif value == 0: self.value_entry.config(state=tk.NORMAL) self.incre_btn.config(state=tk.NORMAL) self.decre_btn.config(state=tk.DISABLED) elif (value > 0) and (value < 10): self.value_entry.config(state=tk.DISABLED) self.incre_btn.config(state=tk.NORMAL) self.decre_btn.config(state=tk.NORMAL) else: if event.widget == self.incre_btn: if (value >= 0) and (value < 10): value += 1 self.value_entry.config(state=tk.NORMAL) self.value_entry.delete("0", "end") self.value_entry.insert("end", str(value)) if value > 0: self.decre_btn.config(state=tk.NORMAL) self.value_entry.config(state=tk.DISABLED) if value == 10: self.incre_btn.config(state=tk.DISABLED) elif event.widget == self.decre_btn: if (value > 0) and (value <= 10): value -= 1 self.value_entry.config(state=tk.NORMAL) self.value_entry.delete("0", "end") self.value_entry.insert("end", str(value)) self.value_entry.config(state=tk.DISABLED) if (value) < 10: self.incre_btn.config(state=tk.NORMAL) if (value) == 0: self.decre_btn.config(state=tk.DISABLED) self.value_entry.config(state=tk.NORMAL) def main(): app = MyForm() app.mainloop() if __name__ == "__main__": main() Result: [1]
library(gWidgets) options(guiToolkit="RGtk2") ## using gWidgtsRGtk2 w <- gwindow("Disable components") g <- ggroup(cont=w, horizontal=FALSE) e <- gedit("0", cont=g, coerce.with=as.numeric) bg <- ggroup(cont=g) down_btn <- gbutton("-", cont=bg) up_btn <- gbutton("+", cont=bg) update_ctrls <- function(h,...) { val <- svalue(e) enabled(down_btn) <- val >= 0 enabled(up_btn) <- val <= 10 } rement <- function(h,...) { svalue(e) <- svalue(e) + h$action update_ctrls(h,...) } addHandlerChanged(e, handler=update_ctrls) addHandlerChanged(down_btn, handler=rement, action=-1) addHandlerChanged(up_btn, handler=rement, action=1) #lang racket/gui (define frame (new frame% [label "Interaction Demo"])) (define (changed . _) (define s (send inp get-value)) (define v (string->number s)) (unless v (set! v (or (string->number (regexp-replace* #rx"[^0-9]+" s "")) 0)) (send inp set-value (~a v))) (send inc-b enable (< v 10)) (send dec-b enable (> v 0)) (send inp enable (zero? v))) (define ((change-value f) . _) (send inp set-value (number->string (f (string->number (send inp get-value))))) (changed)) (define inp (new text-field% [label "Value"] [parent frame] [init-value "0"] [callback changed])) (define buttons (new horizontal-pane% [parent frame])) (define inc-b (new button% [parent buttons] [label "Increment"] [callback (change-value add1)])) (define dec-b (new button% [parent buttons] [label "Decrement"] [callback (change-value sub1)])) (send frame show #t) (formerly Perl 6) Extremely basic implementation using the GTK library.
use GTK::Simple; use GTK::Simple::App; my GTK::Simple::App $app .= new( title => 'Controls Enable / Disable' ); $app.set-content( my $box = GTK::Simple::HBox.new( my $inc = GTK::Simple::Button.new( label => ' + ' ), my $value = GTK::Simple::Entry.new, my $dec = GTK::Simple::Button.new( label => ' - ' ) ) ); $app.border-width = 10; $box.spacing = 10; $value.changed.tap: { $value.text.=subst(/\D/, ''); $inc.sensitive = $value.text < 10; $dec.sensitive = $value.text > 0; } $value.text = '0'; $inc.clicked.tap: { my $val = $value.text; $val += 1; $value.text = $val.Str } $dec.clicked.tap: { my $val = $value.text; $val -= 1; $value.text = $val.Str } $app.run; Red[] enable: does [ f/enabled?: 0 = n i/enabled?: 10 > n d/enabled?: 0 < n ] view [ f: field "0" [either error? try [n: to-integer f/text] [f/text: "0"] [enable]] i: button "increment" [f/text: mold n: add to-integer f/text 1 enable] d: button "decrement" disabled [f/text: mold n: subtract to-integer f/text 1 enable] ] Load "guilib.ring" MyApp = New qApp { num = 0 win1 = new qWidget() { setwindowtitle("Hello World") setGeometry(100,100,370,250) btn1 = new qpushbutton(win1) { setGeometry(50,200,100,30) settext("Increment") setclickevent("Increment()")} btn2 = new qpushbutton(win1) { setGeometry(200,200,100,30) settext("Decrement") setclickevent("Decrement()")} lineedit1 = new qlineedit(win1) { setGeometry(10,100,350,30) settext("0")} show()} exec()} func Increment lineedit1{ num = text()} num = string(number(num)+1) lineedit1.settext(num) if number(num)>9 btn1.setDisabled(True) ok func Decrement lineedit1{ num = text()} num = string(number(num)-1) lineedit1.settext(num) if number(num)<0 btn2.setDisabled(True) okShoes.app do @number = edit_line @number.change {update_controls} @incr = button('Increment') {update_controls(@number.text.to_i + 1)} @decr = button('Decrement') {update_controls(@number.text.to_i - 1)} def update_controls(value = @number.text.to_i) @number.text = value @incr.state = value.to_i >= 10 ? "disabled" : nil @decr.state = value.to_i <= 0 ? "disabled" : nil end update_controls 0 end import swing.{ BoxPanel, Button, GridPanel, Orientation, Swing, TextField } import swing.event.{ ButtonClicked, Key, KeyPressed, KeyTyped } object Enabling extends swing.SimpleSwingApplication { def top = new swing.MainFrame { title = "Rosetta Code >>> Task: GUI enabling/disabling of controls | Language: Scala" val numberField = new TextField { text = "0" // start at 0 horizontalAlignment = swing.Alignment.Right } val (incButton, decButton) = (new Button("Increment"), // Two variables initialized new Button("Decrement") { enabled = false }) // arrange buttons in a grid with 1 row, 2 columns val buttonPanel = new GridPanel(1, 2) { contents ++= List(incButton, decButton) } // arrange text field and button panel in a grid with 2 row, 1 column contents = new BoxPanel(Orientation.Vertical) { contents ++= List(numberField, buttonPanel) } val specialKeys = List(Key.BackSpace, Key.Delete) // listen for keys pressed in numberField and button clicks listenTo(numberField.keys, incButton, decButton) reactions += { case kt: KeyTyped => if (kt.char.isDigit) // if the entered char is a digit ... Swing.onEDT(switching) // ensure GUI-updating else kt.consume // ... eat the event (i.e. stop it from being processed) case KeyPressed(_, kp, _, _) if (!specialKeys.contains(kp)) => Swing.onEDT(switching) // ensure GUI-updating case ButtonClicked(`incButton`) => numberField.text = (numberField.text.toLong + 1).toString switching case ButtonClicked(`decButton`) => numberField.text = (numberField.text.toLong - 1).toString switching } def switching = { val n = (if (numberField.text.isEmpty()) "0" else numberField.text).toLong numberField.text = n.toString numberField.enabled = n == 0 incButton.enabled = n < 10 decButton.enabled = n > 0 } centerOnScreen() } // def top( } |top input vh incButton decButton| vh := ValueHolder with:0. top := StandardSystemView label:'Rosetta GUI interaction'. top extent:300@100. top add:((Label label:'Value:') origin: 0 @ 10 corner: 100 @ 40). top add:(input := EditField origin: 102 @ 10 corner: 1.0 @ 40). input model:(TypeConverter onNumberValue:vh). input enableChannel:(BlockValue with:[:v | v = 0] argument:vh). top add:((incButton := Button label:'Inc') origin: 10 @ 50 corner: 100 @ 80). top add:((decButton := Button label:'Dec') origin: 110 @ 50 corner: 210 @ 80). incButton action:[ vh value: (vh value + 1) ]. incButton enableChannel:(BlockValue with:[:v | v < 10] argument:vh). decButton action:[ vh value: (vh value - 1) ]. decButton enableChannel:(BlockValue with:[:v | v > 0] argument:vh). top open package require Tk # Model set field 0 # View place [ttk::frame .bg] -relwidth 1 -relheight 1; # Hack to make things look nice pack [ttk::labelframe .val -text "Value"] pack [ttk::entry .val.ue -textvariable field \ -validate key -invalidcommand bell \ -validatecommand {string is integer %P}] pack [ttk::button .inc -text "increment" -command up] pack [ttk::button .dec -text "decrement" -command down] # Controller proc up {} { global field incr field } proc down {} { global field incr field -1 } # Attach this controller to the Model; easier than manual calling trace add variable field write updateEnables proc updateEnables {args} { global field .inc state [expr {$field < 10 ? "!disabled" : "disabled"}] .dec state [expr {$field > 0 ? "!disabled" : "disabled"}] } updateEnables; # Force initial state of buttons bool validate_input(Gtk.Window window, string str){ int64 val; bool ret = int64.try_parse(str,out val);; if(!ret || str == ""){ var dialog = new Gtk.MessageDialog(window, Gtk.DialogFlags.MODAL, Gtk.MessageType.ERROR, Gtk.ButtonsType.OK, "Invalid value"); dialog.run(); dialog.destroy(); } if(str == ""){ ret = false; } return ret; } int main (string[] args) { Gtk.init (ref args); var window = new Gtk.Window(); window.title = "Rosetta Code"; window.window_position = Gtk.WindowPosition.CENTER; window.destroy.connect(Gtk.main_quit); window.set_default_size(0,0); var box = new Gtk.Box(Gtk.Orientation.HORIZONTAL, 1); box.set_border_width(1); var label = new Gtk.Label("Value:"); var entry = new Gtk.Entry(); var ib = new Gtk.Button.with_label("inc"); var db = new Gtk.Button.with_label("dec"); ib.set_sensitive(true); //enable the inc button db.set_sensitive(false); //disable the dec button entry.set_text("0"); //initialize to zero entry.activate.connect(() => { var str = entry.get_text(); if(!validate_input(window, str)){ entry.set_text("0"); //initialize to zero on wrong input }else{ int num = int.parse(str); if(num != 0){ entry.set_sensitive(false); //disable the field } if(num > 0 && num < 10){ ib.set_sensitive(true); //enable the inc button db.set_sensitive(true); //enable the dec button } if(num > 9){ ib.set_sensitive(false); //disable the inc button db.set_sensitive(true); //enable the dec button } } }); ib.clicked.connect(() => { // read and validate the entered value if(!validate_input(window, entry.get_text())){ entry.set_text("0"); //initialize to zero on wrong input }else{ int num = int.parse(entry.get_text()) + 1; entry.set_text(num.to_string()); if(num > 9){ ib.set_sensitive(false); //disable the inc button } if(num != 0){ db.set_sensitive(true); //enable the dec button entry.set_sensitive(false); //disable the field } if(num == 0){ entry.set_sensitive(true); //enable the field } if(num < 0){ db.set_sensitive(false); //disable the dec button } } }); db.clicked.connect(() => { // read and validate the entered value int num = int.parse(entry.get_text()) - 1; entry.set_text(num.to_string()); if(num == 0){ db.set_sensitive(false); //disable the dec button entry.set_sensitive(true); //enable the field } if(num < 10){ ib.set_sensitive(true); //enable the inc button } }); box.pack_start(label, false, false, 2); box.pack_start(entry, false, false, 2); box.pack_start(ib, false, false, 2); box.pack_start(db, false, false, 2); window.add(box); window.show_all(); Gtk.main(); return 0; } In VB, windows are usually created in the IDE. The generated code is hidden from the user unless viewed outside of VB. For the sake of this task, I have included that code.
(Also, this sort of task would typically be performed by a "spinner" or "up-down" control, not by buttons.)
VERSION 5.00 Begin VB.Form Form1 Caption = "Form1" ClientHeight = 2265 ClientLeft = 60 ClientTop = 600 ClientWidth = 2175 LinkTopic = "Form1" ScaleHeight = 2265 ScaleWidth = 2175 StartUpPosition = 3 'Windows Default Begin VB.CommandButton cmdDec Caption = "Decrement" Enabled = 0 'False Height = 495 Left = 120 TabIndex = 2 Top = 1680 Width = 1215 End Begin VB.CommandButton cmdInc Caption = "Increment" Height = 495 Left = 120 TabIndex = 1 Top = 1080 Width = 1215 End Begin VB.TextBox txtValue Height = 495 Left = 120 TabIndex = 0 Text = "0" Top = 240 Width = 1215 End End Attribute VB_Name = "Form1" Attribute VB_GlobalNameSpace = False Attribute VB_Creatable = False Attribute VB_PredeclaredId = True Attribute VB_Exposed = False '-----user-written code begins here; everything above this line is hidden in the GUI----- Private Sub cmdDec_Click() If Val(txtValue.Text) > 0 Then txtValue.Text = Val(txtValue.Text) - 1 End Sub Private Sub cmdInc_Click() If Val(txtValue.Text) < 10 Then txtValue.Text = Val(txtValue.Text) + 1 End Sub Private Sub txtValue_Change() Select Case Val(txtValue.Text) Case Is < 0 txtValue.Enabled = False cmdInc.Enabled = True cmdDec.Enabled = False Case Is > 9 txtValue.Enabled = False cmdInc.Enabled = False cmdDec.Enabled = True Case 0 txtValue.Enabled = True cmdInc.Enabled = True cmdDec.Enabled = False Case Else txtValue.Enabled = False cmdInc.Enabled = True cmdDec.Enabled = True End Select End Sub Graphical
Notes:
- Make sure you have the ui module installed or update your version of V
- For alternative UI toolkits, check github.com/vlang/awesome-v (Awesome V).
import ui import gx const ( win_width = 400 win_height = 40 ) @[heap] struct App { mut: window &ui.Window = unsafe {nil} counter string = "0" } fn main() { mut app := &App{} app.window = ui.window( width: win_width height: win_height title: "Counter" mode: .resizable layout: ui.row( spacing: 5 margin_: 10 widths: ui.stretch heights: ui.stretch children: [ ui.textbox( max_len: 20 read_only: false is_numeric: true text: &app.counter ), ui.button( text: "increment" bg_color: gx.light_gray radius: 5 border_color: gx.gray on_click: app.btn_click_inc ), ui.button( text: "decrement" bg_color: gx.light_gray radius: 5 border_color: gx.gray on_click: app.btn_click_dec ), ] ) ) ui.run(app.window) } fn (mut app App) btn_click_inc(mut btn ui.Button) { if app.counter.int() > 10 { btn.disabled = true return } app.counter = (app.counter.int() + 1).str() } fn (mut app App) btn_click_dec(mut btn ui.Button) { if app.counter.int() < 0 { btn.disabled = true return } app.counter = (app.counter.int() - 1).str() } import "graphics" for Canvas, Color import "input" for Mouse, Keyboard import "dome" for Window import "./polygon" for Polygon class Button { construct new(x, y, w, h, legend, c, oc, lc) { var vertices = [[x, y], [x+w, y], [x+w, y+h], [x, y+h]] _rect = Polygon.quick(vertices) _x = x _y = y _w = w _h = h _legend = legend _c = c _oc = oc _lc = lc _enabled = true } enabled { _enabled } enabled=(e) { _enabled = e } draw() { _rect.drawfill(_c) _rect.draw(_oc) var l = Canvas.getPrintArea(_legend) var lx = ((_w - l.x)/2).truncate lx = (lx > 0) ? _x + lx : _x + 1 var ly = ((_h - l.y)/2).truncate ly = (ly > 0) ? _y + ly : _y + 1 var col = _enabled ? _lc : Color.darkgray Canvas.print(_legend, lx, ly, col) } justClicked { Mouse["left"].justPressed && _rect.contains(Mouse.position.x, Mouse.position.y) } } class TextBox { construct new(x, y, w, h, label, c, oc, lc) { var vertices = [[x, y], [x+w, y], [x+w, y+h], [x, y+h]] _rect = Polygon.quick(vertices) _x = x _y = y _w = w _h = h _label = label _c = c _oc = oc _lc = lc _text = "" _enabled = true } text { _text } text=(t) { _text = t } enabled { _enabled } enabled=(e) { _enabled = e } draw() { _rect.drawfill(_c) _rect.draw(_oc) var l = Canvas.getPrintArea(_label).x var lx = _x - l - 7 if (lx < 1) { lx = 1 _label = _label[0..._x] } var col = _enabled ? _lc : Color.darkgray Canvas.print(_label, lx, _y, col) Canvas.getPrintArea(_label).x Canvas.print(_text, _x + 3, _y + 1, Color.black) } } class GUIControlEnablement { construct new() { Window.title = "GUI control enablement" _btnIncrement = Button.new(60, 40, 80, 80, "Increment", Color.red, Color.blue, Color.white) _btnDecrement = Button.new(180, 40, 80, 80, "Decrement", Color.green, Color.blue, Color.white) _txtValue = TextBox.new(140, 160, 80, 8, "Value", Color.white, Color.blue, Color.white) _txtValue.text = "0" Keyboard.handleText = true } init() { _btnDecrement.enabled = false drawControls() } update() { if (_btnIncrement.enabled && _btnIncrement.justClicked) { var number = Num.fromString(_txtValue.text) + 1 _btnIncrement.enabled = (number < 10) _btnDecrement.enabled = true _txtValue.enabled = (number == 0) _txtValue.text = number.toString } else if (_btnDecrement.enabled && _btnDecrement.justClicked) { var number = Num.fromString(_txtValue.text) - 1 _btnDecrement.enabled = (number > 0) _btnIncrement.enabled = true _txtValue.enabled = (number == 0) _txtValue.text = number.toString } else if (_txtValue.enabled && "0123456789".any { |d| Keyboard[d].justPressed }) { _txtValue.text = Keyboard.text _txtValue.enabled = (_txtValue.text == "0") _btnIncrement.enabled = true _btnDecrement.enabled = (_txtValue.text != "0") } } draw(alpha) { drawControls() } drawControls() { Canvas.cls() _btnIncrement.draw() _btnDecrement.draw() _txtValue.draw() } } var Game = GUIControlEnablement.new()