better probing of content for smart hint to decide what state to display. fixes #532

Author: ButchersBoy

MainDemo.Wpf/Snackbars.xaml

@@ -7,6 +7,7 @@
  xmlns:materialDesign="http://materialdesigninxaml.net/winfx/xaml/themes"
  mc:Ignorable="d" 
  d:DesignHeight="300" d:DesignWidth="300">
+ 
  <ScrollViewer HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Hidden">
  <Grid Margin="0 0 0 4">
  <Grid.ColumnDefinitions>

MaterialDesignThemes.Wpf/HintProxyFabric.ComboBox.cs

@@ -25,18 +25,26 @@ public object Content
  return _comboBox.Text;
  }
 
- ComboBoxItem comboBoxItem = _comboBox.SelectedItem as ComboBoxItem;
+ var comboBoxItem = _comboBox.SelectedItem as ComboBoxItem;
  return comboBoxItem != null 
  ? comboBoxItem.Content
  : _comboBox.SelectedItem;
  }
  }
 
  public bool IsLoaded => _comboBox.IsLoaded;
- public bool IsVisible => _comboBox.IsVisible;
+
+ public bool IsVisible => _comboBox.IsVisible; 
+
+ public bool IsEmpty()
+ {
+ return string.IsNullOrWhiteSpace(_comboBox.Text);
+ }
 
  public event EventHandler ContentChanged;
+
  public event EventHandler IsVisibleChanged;
+
  public event EventHandler Loaded;
 
  public ComboBoxHintProxy(ComboBox comboBox)

MaterialDesignThemes.Wpf/HintProxyFabric.PasswordBox.cs

@@ -9,8 +9,12 @@ private sealed class PasswordBoxHintProxy : IHintProxy
  {
  private readonly PasswordBox _passwordBox;
 
+ public bool IsEmpty() => string.IsNullOrWhiteSpace(_passwordBox.Password); 
+
  public object Content => _passwordBox.Password;
+
  public bool IsLoaded => _passwordBox.IsLoaded;
+
  public bool IsVisible => _passwordBox.IsVisible;
 
  public event EventHandler ContentChanged;

MaterialDesignThemes.Wpf/HintProxyFabric.TextBox.cs

@@ -11,9 +11,13 @@ private sealed class TextBoxHintProxy : IHintProxy
  private readonly TextBox _textBox;
 
  public object Content => _textBox.Text;
+
  public bool IsLoaded => _textBox.IsLoaded;
+
  public bool IsVisible => _textBox.IsVisible;
 
+ public bool IsEmpty() => string.IsNullOrWhiteSpace(_textBox.Text);
+
  public event EventHandler ContentChanged;
  public event EventHandler IsVisibleChanged;
  public event EventHandler Loaded;

MaterialDesignThemes.Wpf/IHintProxy.cs

@@ -14,6 +14,14 @@ namespace MaterialDesignThemes.Wpf
  /// </summary>
  public interface IHintProxy : IDisposable
  {
+ /// <summary>
+ /// Checks to see if the targetted control can be deemed as logically 
+ /// empty, even if not null, affecting the current hint display.
+ /// </summary>
+ /// <returns></returns>
+ bool IsEmpty();
+
+ [Obsolete]
  object Content { get; }
 
  bool IsLoaded { get; }

MaterialDesignThemes.Wpf/SmartHint.cs

@@ -150,7 +150,7 @@ private static void HintProxyPropertyChangedCallback(DependencyObject dependency
 
  protected virtual void OnHintProxyContentChanged(object sender, EventArgs e)
  {
- IsContentNullOrEmpty = string.IsNullOrEmpty((HintProxy.Content ?? "").ToString());
+ IsContentNullOrEmpty = HintProxy.IsEmpty();
 
  if (HintProxy.IsLoaded)
  {
@@ -182,7 +182,7 @@ private void RefreshState(bool useTransitions)
 
  var action = new Action(() =>
  {
- var state = String.IsNullOrEmpty((proxy.Content ?? String.Empty).ToString())
+ var state = proxy.IsEmpty()
  ? ContentEmptyName
  : ContentNotEmptyName;
 
@@ -198,5 +198,7 @@ private void RefreshState(bool useTransitions)
  Dispatcher.BeginInvoke(action);
  }
  }
+
+
  }
 }