Weird behavior with $WS_EX_MDICHILD

[AoRaToS]

Hello everyone,

I have noticed a weird behavior when using $WS_EX_MDICHILD.

I create a main GUI with 2 buttons.

Each button creates a new GUI.

The first one without $WS_EX_MDICHILD.

The second one with $WS_EX_MDICHILD.

I click the first one and the other GUI is created (without $WS_EX_MDICHILD):

If I drag the main GUI the other GUI is separate and doesn't move, which is expected.

Then I click the second one for the next GUI to be created (with $WS_EX_MDICHILD):

If I now drag the main GUI, both of the other GUIs move with it.

If I close the second GUI, the first one still moves if I drag the main one.

If I close the first one and re-open it, it still moves in relation to the Main GUI (if I drag the main GUI it follows)

Is this how it's supposed to be? Does the style affect all GUIs created even without the style?

Here is a script to try it out:

(Follow the instructions above)

expandcollapse popup

#include <GUIConstantsEx.au3>
#include <WindowsConstants.au3>

Opt("GUIOnEventMode", 1)
Opt("GUICloseOnESC", 0)

Global $Main

MainGUI()


Func MainGUI()
    $Main = GUICreate("Main", 350, 350)
    GUISetOnEvent($GUI_EVENT_CLOSE, "WindowClose")
    $button1 = GUICtrlCreateButton("Child 1 - no MDI_CHILD", 75, 100, 150, 20)
    GUICtrlSetOnEvent($button1, "Child1")
    $button2 = GUICtrlCreateButton("Child 2 - with MDI", 75, 150, 150, 20)
    GUICtrlSetOnEvent($button2, "Child2")
    GUISetState(@SW_SHOW, $Main)
EndFunc

Func Child1()
    $ChildGUI1 = GUICreate("Child 1 - no MDI_CHILD", 180, 180, 100, 100, Default, Default, $Main)
    GUISetOnEvent($GUI_EVENT_CLOSE, "WindowClose")
    GUISetState(@SW_SHOW, $ChildGUI1)
EndFunc

Func Child2()
    $ChildGUI2 = GUICreate("Child 2 - with MDI", 180, 180, 100, 100, Default, $WS_EX_MDICHILD, $Main)
    GUISetOnEvent($GUI_EVENT_CLOSE, "WindowClose")
    GUISetState(@SW_SHOW, $ChildGUI2)
EndFunc


Func WindowClose()
    GUIDelete(@GUI_WinHandle)
    If @GUI_WinHandle = $Main Then
        Exit
    EndIf
EndFunc


While 1
    Sleep(100)
WEnd

I know the example can be coded better (e.g. one function for both GUIs and using @GUI_CTRLHANDLE but this does the job for now)

Edited January 11, 2013 by AoRaToS

[Melba23]

AoRaToS,

The child GUIs are created with exactly the same style and extended style values and these do not change as the GUIs are deleted and recreated. The Help file does tell us that the $WS_EX_MDICHILD style is not true MDI - so I can only imagine that AutoIt is doing something "under the hood" to get the child to follow the main GUI and this affects all children.

I will ask trancexx to pop in and take a look - she will doubtless be able to give you the correct explanation.

M23

[trancexx]

It's a bug. Once one child window of that ex_style is created AutoIt thinks all the child windows are such.

...What can I say.

[AoRaToS]

I have opened a ticket in BugTracker #2300 to see if this will be fixed in an upcoming version!

Edited January 13, 2013 by AoRaToS