event BeforeDrawPart (Part as DrawPartEnum, hDC as Long, X as Long, Y as Long, Width as Long, Height as Long, Cancel as Boolean)
Occurs just before drawing a part of the control.

 TypeDescription 
   Part as DrawPartEnum A Part being painted. If the Part parameter is exOwnerDrawBar, the DrawPartItem property specifies the handle of the item that hosts the "OwnerDraw" bar, while the DrawPartKey property specifies the key of the bar to be painted. Use the Add or Copy method to add an "OwnerDraw" bar  
   hDC as Long A long expression that specifies the handle of the device context where you can perform your own draw ( available for /COM only ). The /NET or /WPF assembly provides a System.Drawing.Graphics object instead hDC parameter  
   X as Long (by reference) A long expression that specifies the left coordinate of the rectangle where the paint should occur. You can change the X parameter during the handler, to define the new left coordinate for the default painting. The /NET or /WPF assembly provides a System.Drawing.Rectangle instead (X, Y, Width, Height ).  
   Y as Long (by reference) A long expression that specifies the top coordinate of the rectangle where the paint should occur. You can change the Y parameter during the handler, to define the new top coordinate for the default painting. The /NET or /WPF assembly provides a System.Drawing.Rectangle instead (X, Y, Width, Height ).  
   Width as Long (by reference) A long expression that specifies the width of the rectangle where the paint should occur. You can change the Width parameter during the handler, to define the new width for the default painting. The /NET or /WPF assembly provides a System.Drawing.Rectangle instead (X, Y, Width, Height ).  
   Height as Long (by reference) A long expression that specifies the height of the rectangle where the paint should occur. You can change the Height parameter during the handler, to define the new width for the default painting. The /NET or /WPF assembly provides a System.Drawing.Rectangle instead (X, Y, Width, Height ).  
   Cancel as Boolean (by reference) A Boolean expression that specifies whether the default painting is canceled or not.  
The BeforeDrawPart and AfterDrawPart events occur when different parts of the control requires to be drawn. Use the BeforeDrawPart and AfterDrawPart events to add your custom drawing to be shown in the component. Use the BeforeDrawPart event to perform your own drawing before the default drawing, canceling the default drawing, or changing the area being assigned to the part part when painting. Use the AfterDrawPart event to perform your own drawing after default painting occurs. The /NET Assembly provides instead hDC and (X,Y,Width,Height) parameters a Graphics object and a Rectangle object, the last being passed by reference. Use the HistogramBoundsChanged event to notify your application when the left part of the histogram is resized, so inside controls must be re-positioned.

Syntax for BeforeDrawPart event, /NET version, on:

private void BeforeDrawPart(object sender,exontrol.EXG2ANTTLib.DrawPartEnum Part,int hDC,ref int X,ref int Y,ref int Width,ref int Height,ref bool Cancel)
{
}

Private Sub BeforeDrawPart(ByVal sender As System.Object,ByVal Part As exontrol.EXG2ANTTLib.DrawPartEnum,ByVal hDC As Integer,ByRef X As Integer,ByRef Y As Integer,ByRef Width As Integer,ByRef Height As Integer,ByRef Cancel As Boolean) Handles BeforeDrawPart
End Sub

Syntax for BeforeDrawPart event, /COM version, on:

private void BeforeDrawPart(object sender, AxEXG2ANTTLib._IG2anttEvents_BeforeDrawPartEvent e)
{
}

void OnBeforeDrawPart(long Part,long hDC,long FAR* X,long FAR* Y,long FAR* Width,long FAR* Height,BOOL FAR* Cancel)
{
}

void __fastcall BeforeDrawPart(TObject *Sender,Exg2anttlib_tlb::DrawPartEnum Part,long hDC,long * X,long * Y,long * Width,long * Height,VARIANT_BOOL * Cancel)
{
}

procedure BeforeDrawPart(ASender: TObject; Part : DrawPartEnum;hDC : Integer;var X : Integer;var Y : Integer;var Width : Integer;var Height : Integer;var Cancel : WordBool);
begin
end;

procedure BeforeDrawPart(sender: System.Object; e: AxEXG2ANTTLib._IG2anttEvents_BeforeDrawPartEvent);
begin
end;

begin event BeforeDrawPart(long Part,long hDC,long X,long Y,long Width,long Height,boolean Cancel)
end event BeforeDrawPart

Private Sub BeforeDrawPart(ByVal sender As System.Object, ByVal e As AxEXG2ANTTLib._IG2anttEvents_BeforeDrawPartEvent) Handles BeforeDrawPart
End Sub

Private Sub BeforeDrawPart(ByVal Part As EXG2ANTTLibCtl.DrawPartEnum,ByVal hDC As Long,X As Long,Y As Long,Width As Long,Height As Long,Cancel As Boolean)
End Sub

Private Sub BeforeDrawPart(ByVal Part As Long,ByVal hDC As Long,X As Long,Y As Long,Width As Long,Height As Long,Cancel As Boolean)
End Sub

LPARAMETERS Part,hDC,X,Y,Width,Height,Cancel

PROCEDURE OnBeforeDrawPart(oG2antt,Part,hDC,X,Y,Width,Height,Cancel)
RETURN

Syntax for BeforeDrawPart event, /COM version (others), on:

<SCRIPT EVENT="BeforeDrawPart(Part,hDC,X,Y,Width,Height,Cancel)" LANGUAGE="JScript">
</SCRIPT>

<SCRIPT LANGUAGE="VBScript">
Function BeforeDrawPart(Part,hDC,X,Y,Width,Height,Cancel)
End Function
</SCRIPT>

Procedure OnComBeforeDrawPart OLEDrawPartEnum llPart Integer llhDC Integer llX Integer llY Integer llWidth Integer llHeight Boolean llCancel
	Forward Send OnComBeforeDrawPart llPart llhDC llX llY llWidth llHeight llCancel
End_Procedure

METHOD OCX_BeforeDrawPart(Part,hDC,X,Y,Width,Height,Cancel) CLASS MainDialog
RETURN NIL

void onEvent_BeforeDrawPart(int _Part,int _hDC,COMVariant /*long*/ _X,COMVariant /*long*/ _Y,COMVariant /*long*/ _Width,COMVariant /*long*/ _Height,COMVariant /*bool*/ _Cancel)
{
}

function BeforeDrawPart as v (Part as OLE::Exontrol.G2antt.1::DrawPartEnum,hDC as N,X as N,Y as N,Width as N,Height as N,Cancel as L)
end function

function nativeObject_BeforeDrawPart(Part,hDC,X,Y,Width,Height,Cancel)
return

The following VB sample changes the Y and the Height parameters, and paints the "Histogram" text inside the histogram as shown bellow in the screen shot:

Private Type RECT
        Left As Long
        Top As Long
        Right As Long
        Bottom As Long
End Type
Private Const DT_SINGLELINE = &H20
Private Const DT_CENTER = &H1
Private Declare Function DrawText Lib "user32" Alias "DrawTextA" (ByVal hdc As Long, ByVal lpStr As String, ByVal nCount As Long, lpRect As RECT, ByVal wFormat As Long) As Long


Private Sub G2antt1_BeforeDrawPart(ByVal Part As EXG2ANTTLibCtl.DrawPartEnum, ByVal hdc As Long, X As Long, Y As Long, Width As Long, Height As Long, Cancel As Boolean)
    If (Part = exDrawLeftHistogram) Or (Part = exDrawRightHistogram) Then
    
        Dim h As Long
        h = 16
        
        If ((Part = exDrawRightHistogram)) Then
            Dim r As RECT
            r.Left = X + 2
            r.Right = r.Left + Width - 4
            r.Top = Y + 1
            r.Bottom = r.Top + h - 2
            
            DrawText hdc, "Histogram", 9, r, DT_SINGLELINE + DT_CENTER
        End If

        Y = Y + h
        Height = Height - h
    End If
End Sub


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