ListBox: ActiveGadget()=NULL

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Midimaster(Posted 2013) [#1]
This report points to a difference between MaxGui for Windows and MaxGui for OsX. On OsX it causes a crash:

The function ActiveGadget() should retun the active Gadget. When I click on an item in a listbox, tihs function return the listbox itself.

On OsX the function return NULL.

To simulate the bug use the original manual example for CreateListBox() and add this lines:

While WaitEvent()
	Print CurrentEvent.ToString()
	Select EventID()
	End Select
;add this:------------------------------------------------------------
	Print "step 1"
	Print "WINDOW GADGET=" + GadgetText(Window)
	If ActiveGadget()<>Null
		Print "Gadget is aktiv"
	    Print "Gadget is NULL"
	Print "step 2"
	Print "Name of Gadget=" + GadgetText(ActiveGadget())

I know it is not good to call GadgetText() of a NULL object, but remember on Windows the ActiveGadget() returns a value!!!

This bug is fatal if you want to know, in which window an event occured. Normaly you can search for the mother of a gadget upto you reach a "WINDOW"-Gadget:

Function SearchActiveWindow:TGadget()
	Local tmpGadget:TGadget = ActiveGadget()
	While (tmpGadget<> Null) And (GadgetClass(tmpGadget) <> GADGET_WINDOW)
		tmpGadget = GadgetGroup(tmpGadget)
	Return tmpGadget
End Function

this is where I dedected the bug. I found the bug on OsX 10.6 with BlitzMax 1.48 (with official MaxGui)

skidracer(Posted 2013) [#2]
Here is modified CreateListBox example. On OSX I am getting ActiveGadget and EventGadget non NULL for ListBox events, but NULL for window events like dragging the window (seems wrong) so am a bit confused.

Midimaster(Posted 2013) [#3]
Hello skidracer,

this sounds strange: The problem for me is the EVENT_GADGETSELECT event. After this event the ActiveGadget() returns NULL instead of the "Listbox" on OsX 10.6

What will you tell me with your sample code? What shall I test?