//+------------------------------------------------------------------+
//| Demo_iAC.mq5 |
//| Copyright 2011, MetaQuotes Software Corp. |
//| https://www.mql5.com |
//+------------------------------------------------------------------+
#property copyright "Copyright 2000-2024, MetaQuotes Ltd."
#property link "https://www.mql5.com"
#property version "1.00"
#property description "The indicator demonstrates how to obtain data"
#property description "of indicator buffers for the iAC technical indicator."
#property description "A symbol and timeframe used for calculation of the indicator,"
#property description "are set by the symbol and period parameters."
#property description "The method of creation of the handle is set through the 'type' parameter (function type)."
#property indicator_separate_window
#property indicator_buffers 2
#property indicator_plots 1
//--- plotting of iAC
#property indicator_label1 "iAC"
#property indicator_type1 DRAW_COLOR_HISTOGRAM
#property indicator_color1 clrGreen, clrRed
#property indicator_style1 STYLE_SOLID
#property indicator_width1 1
//+------------------------------------------------------------------+
//| Enumeration of the methods of handle creation |
//+------------------------------------------------------------------+
enum Creation
{
Call_iAC, // use iAC
Call_IndicatorCreate // use IndicatorCreate
};
//--- input parameters
input Creation type=Call_iAC; // type of the function
input string symbol=" "; // symbol
input ENUM_TIMEFRAMES period=PERIOD_CURRENT; // timeframe
//--- indicator buffers
double iACBuffer[];
double iACColors[];
//--- variable for storing the handle of the iAC indicator
int handle;
//--- variable for storing
string name=symbol;
//--- name of the indicator on a chart
string short_name;
//--- we will keep the number of values in the Accelerator Oscillator indicator
int bars_calculated=0;
//+------------------------------------------------------------------+
//| Custom indicator initialization function |
//+------------------------------------------------------------------+
int OnInit()
{
//--- assignment of arrays to indicator buffers
SetIndexBuffer(0,iACBuffer,INDICATOR_DATA);
SetIndexBuffer(1,iACColors,INDICATOR_COLOR_INDEX);
//--- determine the symbol the indicator is drawn for
name=symbol;
//--- delete spaces to the right and to the left
StringTrimRight(name);
StringTrimLeft(name);
//--- if it results in zero length of the 'name' string
if(StringLen(name)==0)
{
//--- take the symbol of the chart the indicator is attached to
name=_Symbol;
}
//--- create handle of the indicator
if(type==Call_iAC)
handle=iAC(name,period);
else
handle=IndicatorCreate(name,period,IND_AC);
//--- if the handle is not created
if(handle==INVALID_HANDLE)
{
//--- tell about the failure and output the error code
PrintFormat("Failed to create handle of the iAC indicator for the symbol %s/%s, error code %d",
name,
EnumToString(period),
GetLastError());
//--- the indicator is stopped early
return(INIT_FAILED);
}
//--- show the symbol/timeframe the Accelerator Oscillator indicator is calculated for
short_name=StringFormat("iAC(%s/%s)",name,EnumToString(period));
IndicatorSetString(INDICATOR_SHORTNAME,short_name);
//--- normal initialization of the indicator
return(INIT_SUCCEEDED);
}
//+------------------------------------------------------------------+
//| Custom indicator iteration function |
//+------------------------------------------------------------------+
int OnCalculate(const int rates_total,
const int prev_calculated,
const datetime &time[],
const double &open[],
const double &high[],
const double &low[],
const double &close[],
const long &tick_volume[],
const long &volume[],
const int &spread[])
{
//--- number of values copied from the iAC indicator
int values_to_copy;
//--- determine the number of values calculated in the indicator
int calculated=BarsCalculated(handle);
if(calculated<=0)
{
PrintFormat("BarsCalculated() returned %d, error code %d",calculated,GetLastError());
return(0);
}
//--- if it is the first start of calculation of the indicator or if the number of values in the iAC indicator changed
//---or if it is necessary to calculated the indicator for two or more bars (it means something has changed in the price history)
if(prev_calculated==0 || calculated!=bars_calculated || rates_total>prev_calculated+1)
{
//--- if the iACBuffer array is greater than the number of values in the iAC indicator for symbol/period, then we don't copy everything
//--- otherwise, we copy less than the size of indicator buffers
if(calculated>rates_total) values_to_copy=rates_total;
else values_to_copy=calculated;
}
else
{
//--- it means that it's not the first time of the indicator calculation, and since the last call of OnCalculate()
//--- for calculation not more than one bar is added
values_to_copy=(rates_total-prev_calculated)+1;
}
//--- fill the iACBuffer and iACColors arrays with values from the Accelerator Oscillator indicator
//--- if FillArraysFromBuffer returns false, it means the information is nor ready yet, quit operation
if(!FillArraysFromBuffer(iACBuffer,iACColors,handle,values_to_copy)) return(0);
//--- form the message
string comm=StringFormat("%s ==> Updated value in the indicator %s: %d",
TimeToString(TimeCurrent(),TIME_DATE|TIME_SECONDS),
short_name,
values_to_copy);
//--- display the service message on the chart
Comment(comm);
//--- memorize the number of values in the Accelerator Oscillator indicator
bars_calculated=calculated;
//--- return the prev_calculated value for the next call
return(rates_total);
}
//+------------------------------------------------------------------+
//| Filling indicator buffers from the iAC indicator |
//+------------------------------------------------------------------+
bool FillArraysFromBuffer(double &values[], // indicator buffer of Accelerator Oscillator values
double &color_indexes[], // color buffer (for storing of color indexes)
int ind_handle, // handle of the iAC indicator
int amount // number of copied values
)
{
//--- reset error code
ResetLastError();
//--- fill a part of the iACBuffer array with values from the indicator buffer that has 0 index
if(CopyBuffer(ind_handle,0,0,amount,values)<0)
{
//--- if the copying fails, tell the error code
PrintFormat("Failed to copy data from the iAC indicator, error code %d",GetLastError());
//--- quit with zero result - it means that the indicator is considered as not calculated
return(false);
}
//--- now copy the indexes of colors
if(CopyBuffer(ind_handle,1,0,amount,color_indexes)<0)
{
//--- if the copying fails, tell the error code
PrintFormat("Failed to copy color values from the iAC indicator, error code %d",GetLastError());
//--- quit with zero result - it means that the indicator is considered as not calculated
return(false);
}
//--- everything is fine
return(true);
}
//+------------------------------------------------------------------+
//| Indicator deinitialization function |
//+------------------------------------------------------------------+
void OnDeinit(const int reason)
{
if(handle!=INVALID_HANDLE)
IndicatorRelease(handle);
//--- clear the chart after deleting the indicator
Comment("");
} |