TabControl slows other controls and causes flickering

[HeuristicLab-Trac-Bot]

Issue migrated from trac ticket # 2607

milestone: HeuristicLab 3.3.x Backlog | component: MainForm.WindowsForms | priority: medium

2016-05-12 15:02:05: @NimZwei created the issue

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Controls on a TabControl resize slowly and flicker, as also reported on varios stack overflow articles (see below). In cases where calculation intensive resizing is involved (e.g. charts), the GUI freezes shortly due to resizing and flickers.

Most articles suggest setting the WS_EX_COMPOSITED flag on the TabControl:

protected override CreateParams CreateParams {
  get {
    CreateParams cp = base.CreateParams;
    cp.ExStyle |= 0x02000000;  // Turn on WS_EX_COMPOSITED
    return cp;
  }
}

Some authors warn of possible side effects of this flag, so this should be properly tested.

http://stackoverflow.com/questions/4690426/why-do-my-winforms-controls-flicker-and-resize-slowly http://stackoverflow.com/questions/3111841/tabcontrol-blinks-if-image-is-background http://stackoverflow.com/questions/2612487/how-to-fix-the-flickering-in-user-controls?lq=1 http://stackoverflow.com/questions/16925369/tabcontrol-flickering

[HeuristicLab-Trac-Bot]

2016-05-12 15:03:21: @NimZwei uploaded file Enable WS_EX_COMPOSITED on DragOverTabControl.patch (0.5 KiB)

[HeuristicLab-Trac-Bot]

2016-07-08 15:55:10: @NimZwei changed milestone from HeuristicLab 3.3.14 to HeuristicLab 3.3.x Backlog

[HeuristicLab-Trac-Bot]

2019-01-04 19:29:37: @gkronber changed status from new to assigned

[HeuristicLab-Trac-Bot]

2019-01-04 19:29:37: @gkronber set owner to @gkronber

[HeuristicLab-Trac-Bot]

2019-01-04 19:29:37: @gkronber commented

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I quickly tested the patch to check whether this has an effect on the extreme lag of enabling / disabling of controls but found no noticeable improvement. It might still have a positive effect on resizing though. I have not tested this.

[HeuristicLab-Trac-Bot]

2019-01-04 19:29:37: @gkronber