wxGridBagSizer and hidden items broken in 2.8.8.0

wxPython Dev
1

Going from 2.8.7.1 to 2.8.8.0 I noticed that some of my windows using
wxGridBagSizer looked strange.

It looks if you hide an item that's in a GBSizer, the sizer calculates its
minimum like the item was still shown. There's a small demo and an image of the
difference between 2.8.7.1 - 2.8.8.0 here:

http://papernapkin.org/pastebin/view/1477/

And here's the demo code reproduced in case that goes away:

import wx

def test_HiddenItem():
    f = wx.Frame(None)

    f.Sizer = fx = wx.GridBagSizer(6, 6)
    fx.SetEmptyCellSize((0, 0))

    s1 = wx.StaticText(f, -1, 'Test one two three')
    s2 = wx.StaticText(f, -1, 'Test four five six')
    s3 = wx.StaticText(f, -1, 'Test seven eight nine')

    # hide the middle item: it still takes up space in 2.8.8.0
    s2.Hide()

    fx.Add(s1, (0, 0))
    fx.Add(s2, (1, 0))
    fx.Add(s3, (2, 0))

    f.Show()

def main():
    a = wx.PySimpleApp()
    test_HiddenItem()
    a.MainLoop()

if __name__ == '__main__':
    main()

I noticed a backport involving a flag called wxRESERVE_SPACE_EVEN_IF_HIDDEN but
I haven't had time to check it out yet.

2

It looks if you hide an item that's in a GBSizer, the sizer calculates its
minimum like the item was still shown. There's a small demo and an image of the
difference between 2.8.7.1 - 2.8.8.0 here:

http://papernapkin.org/pastebin/view/1477/

This particular case is fixed if I change

    if ( !item )

in wxGridBagSizer::AdjustForOverflow() to

   if ( !item || !item->ShouldAccountFor() )

I'm not entirely sure if this is correct, but it seems to work for me :slight_smile:

- Kevin

3

Kevin Watters wrote:

It looks if you hide an item that's in a GBSizer, the sizer calculates its
minimum like the item was still shown. There's a small demo and an image of the
difference between 2.8.7.1 - 2.8.8.0 here:

http://papernapkin.org/pastebin/view/1477/

This particular case is fixed if I change

    if ( !item )

in wxGridBagSizer::AdjustForOverflow() to

   if ( !item || !item->ShouldAccountFor() )

I'm not entirely sure if this is correct, but it seems to work for me :slight_smile:

Thanks. I'll dig up my test case for that change and try it out with your modification. I think that the ShouldAccountFor code happened at about the same time as my AdjustForOverflow change so there wasn't any cross-checking because neither of us understood the other's motivations :wink:

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Robin Dunn
Software Craftsman
http://wxPython.org Java give you jitters? Relax with wxPython!