The "Invalid operation in GDI+ (Code: 11)" exception can occur on drawing an extra pane item of a TdxBarApplicationMenu component if its ExtraPane.AllowPinItems property is set to False

When drawing the elements in the ExtraPane in the application menu of a ribbon, an EdxGdipException may occur with the message listed in the subject. TdxBarSkinnedPainter.ExtraMenuDrawButton() has the following line of code to :

Delphi
ExtraMenuDrawPinButton(ADrawParams, ADrawParams.BarItemControl.FParts[epbcpPinButton]);

This is all well and good, except the FParts field (part of TdxBarItemControl) is a dynamic array whose length is defined by the TdxBarItemControl.GetPartCount() virtual call. In this function call, BarItemControl is of type TdxBarExtraPaneButtonControl, meaning the GetPartCount() is overridden in TdxBarButtonControl.GetPartCount(). We see TdxBarButtonControl.GetPartCount() defined as the following:

Delphi
function TdxBarButtonControl.GetPartCount: Integer;
begin
  if FDrawParams.IsDropDown then
    Result := 2
  else
    Result := 1;
end;

The gist of all of this is that FParts is indexed to index epbcpPinButton (index 1), when the array may only have 1 valid index, namely index 0. As a result, down the line when TdxGPCanvas.FillRectangle() is called and passed a TRect from a region beyond the end of the valid FParts array, GDI+ will complain about an invalid rectangle. Somehow a check needs to be performed before to see if calling ExtraMenuDrawPinButton() is even necessary so that the dynamic array isn't indexed beyond its valid end.