I’m trying to remove all DesktopContainers to a given window (before filling the window with new containers). It should be oblivious, but I can’t make it to work.
The containers are in a control array, so one is already placed in the window, to begin with.
This code:
do
Var c As CNTAudioVolume=CNTAV1(0) 'CNTAudioVolume is the class, CNTAV1 is the name
if c=nil then Exit
c.Close
loop
… loops forever. It seems like c isn’t nil but its Close method doesn’t remove it from the window (the Close method correctly removes containers whose index is greater than 0).
I can’t find another way to remove an existing DesktopContainer from a window; also, Issues doesn’t find a case describing this problem.
One way would be to change the loop above, replacing (0) by (1) to remove all but the first container, and then hide the remaining one, but that’d be a workaround.
I find strange a DesktopContainer(0) can’t be removed from a window .
If the Close method was working as it should, Container(0) would always be the “next” container, up to the point where there’s no container anymore, at which point the loop would exit.
That’s what I’m saying. The infinite loop occurs because the Close method doesn’t remove the object as it should.
Yes, I’ve only heard this 40,000 times in my 20 years of RealXojo use and forum participation. I was suggesting it as an experiment only (“What happens if…”), to try and track down the source of the issue, but I guess I didn’t make that clear enough in my post.
The irony of your suggestion is that you’re probably on the right track as to what the issue is: the tight loop in the code is preventing the GUI from updating. But that’s no reason to reach for the bug-maker that is DoEvents. Simply redesign the closing code to take this into account.
Ha. Despite Xojo and the IDE having told us for many years that container arrays are unsupported, you can actually create and use them just fine - simply enter their indices manually. I don’t know why they don’t just support them officially.
Or maybe Arnaud has made his own array and filled it with ContainerControls and is not using a ControlArray at all.
@Arnaud_N Perhaps did you create an Array, of DesktopContainers? (An Array of Containers is not the same thing as a Control Array)
If so, then here’s your problem - when you call c.close, the DesktopContainer will be closed, but the reference to it will still exist in your array. Xojo won’t destroy an object (setting it to Nil) until the last reference to the object is gone.
If I’m right, then this code should work:
while CNTAudioVolume.ubound >= 0
CNTAudioVolume(0).close // this closes the DesktopContainer, but does not destroy it
CNTAudioVolume(0).remove // this removes the reference from the array, which allows the destructor to fire
wend
@Julia_Truchsess - What version are you using? I’m trying the latest beta, and I don’t see any way to create a control Array, either using DesktopContainers or regular old ContainerControls. They may have already removed your beloved hack!??!
Edit to add: I tried it as far back as 2019R1.1 and it doesn’t work there, either. I get the yellow error message when I try to change the name of the ContainerControl just like shown above.
I submitted a couple of bug reports / feature requests regarding the documentation:
You are correct, doing it that way works fine, with both API1 and API2 objects. Doing it the way I was trying (changing the instance name to another instance) fails with the yellow error. That’s very weird.
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