Task icon in Windows

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Eikon

I suposuse you have to pass the memory address of the long variable, not the value itself. Use pointers or even the memory address of your LONG variable when calling the API.

Would you mind showing me how to do that? If you could run the code and try to debug it, I would really appreciate it.

* Update *
Here is the updated code. For some reason, changing my Ints to Longs for calls like GetActiveWindow makes them stop working, so I've left them alone. Also, if Local Icon is cast as a Long instead of an Int, it returns 0.

Import "-lshell32"
Import "-lkernel32"

Extern
	Function LoadIcon:Long(hWnd%, file$z, index%) = "ExtractIconA@12"
End Extern

Extern
	Function GetLastError%() = "GetLastError@0"
End Extern

Extern "win32"
	Function GetActiveWindow%()
	Function GetDesktopWindow%()
	Function GetWindowRect%(hWnd%, lpRect:Byte Ptr)
	Function SetWindowPos%(hWnd%, after%, x%, y%, w%, h%, flags%)
	Function SetClassLong%(hWnd%, nIndex%, dwNewLong:Long) = "SetClassLongA@12"
End Extern

Type lpRECT
	Field l%, t%, r%, b%
End Type

Const GFX_WIDTH = 320, GFX_HEIGHT = 200, BIT_DEPTH = 0, HERTZ = -1
Graphics GFX_WIDTH, GFX_HEIGHT, BIT_DEPTH, HERTZ

Local hWnd% = GetActiveWindow()
Print "hWnd: " + hWnd

Local icon% = LoadIcon(hWnd, "c:\icon.ico", 0)
Print "icon: " + icon

Local ret% = SetClassLong(hWnd, -14, icon)
Print "ret: " + ret
If Not ret Then Notify GetLastError()

Local desk_hWnd% = GetDesktopWindow(), l:lpRect = New lpRECT
GetWindowRect desk_hWnd, l:lpRECT 

SetWindowPos hWnd, -2, (l.r / 2) - (GFX_WIDTH / 2), (l.b / 2) - (GFX_HEIGHT / 2), 0, 0, 1
Repeat; FlushMem; Flip; Until KeyDown(KEY_ESCAPE)

GetLastError is returning 1414, which means "Invalid Icon Handle". Sounds like we're getting closer.