Updated to 7.0, get "This Composite can not have Layout."

[vladdu]

Hi!

I upgraded to 7.0 and noticed that not everything can be opened anymore in the designer view. It complains about things similar to the following:

This Composite can not have Layout.
You attempt to set Layout for {new: org.eclipse.swt.custom.SashForm} ... {}, however by its design you should not do this or setLayout() method just implemented to do nothing. Please clean up your source and remove setLayout() invocation.

The same applies for example to the parent Composite received in createPartControl.

The code however works fine, so I wonder why is this happening. If it's not a bug, could you please point me to the place where these things are documented? Can something be done to disable these checks?

best regards,
Vlad

[Eric Clayberg]

That is the correct error message. Allowing he user to set the layout on a SashForm was a bug in earlier versions because SashForms already have an implicit layout and will not accept a new one (see the source for SashForm setLayout() below). v7.0 adds a strong check to prevent this. Commenting out or removing the call to setLayout() will suppress the error message.

SashForm.png (95.58 KiB) Viewed 517 times

[vladdu]

Thanks for the reply!

Does a similar explanation apply for the layout on the parent Composite received as argument to createPartControl? If yes, you might consider adding a QuickFix that wraps the existing widgets inside a Composite and set the layout on that one instead.

best regards,
Vlad

[Eric Clayberg]

Does a similar explanation apply for the layout on the parent Composite received as argument to createPartControl?

Yes. Both ViewPart and EditorPart set that composite to use a FillLayout.

If yes, you might consider adding a QuickFix that wraps the existing widgets inside a Composite and set the layout on that one instead.

Our ViewPart and EditorPart wizards both place a Composite within the one passed via the createPartControl() method.

Rather than a QuickFix, we have decided to remove the restriction in the latest buold and allow you to override the layout on that passed in Composite (which should be safe).