Question

I need that hwnd to use it in my custom dll.
ExpandConstant('{hwnd}') does not work in uninstaller…

Answer 1

You can get it simply from UninstallProgressForm object’s Handle property. Here’s a sample code that changes text of the uninstall form window by using the Windows API function that changes the text by the passed handle as a proof:

[Code]
#ifdef UNICODE
  #define AW "W"
#else
  #define AW "A"
#endif
function SetWindowText(hWnd: HWND; lpString: string): BOOL;
  external 'SetWindowText{#AW}@user32.dll stdcall';

procedure CurUninstallStepChanged(CurUninstallStep: TUninstallStep);
begin
  if CurUninstallStep = usUninstall then
    SetWindowText(UninstallProgressForm.Handle, 'Caption set by window handle');
end;