Bug 15462 - ComboBox dropdown list is clipped by bottom of screen
Summary: ComboBox dropdown list is clipped by bottom of screen
Alias: None
Product: Class Libraries
Classification: Mono
Component: Windows.Forms ()
Version: 2.10.x
Hardware: PC Linux
: Lowest normal
Target Milestone: Community
Assignee: Bugzilla
Depends on:
Reported: 2013-10-17 12:37 UTC by Stephen McConnel
Modified: 2017-09-01 12:16 UTC (History)
3 users (show)

Is this bug a regression?: ---
Last known good build:

test program to demonstrate bug (10.45 KB, application/zip)
2013-10-17 12:37 UTC, Stephen McConnel
proposed fix (diff against 2.10.9 code) (785 bytes, patch)
2013-10-17 12:39 UTC, Stephen McConnel

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Description Stephen McConnel 2013-10-17 12:37:02 UTC
Created attachment 5162 [details]
test program to demonstrate bug

The dropdown list for a ComboBox can be clipped if the control is too close to the bottom of the screen.  This makes items on the list inaccessible.  Windows/.Net behavior in such cases is to move the listbox to display above the ComboBox's textbox instead of below.
I'm attaching a demo program that demonstrates the problem, and a proposed patch which implements behavior similar to that observed in Windows/.Net.
Comment 1 Stephen McConnel 2013-10-17 12:39:08 UTC
Created attachment 5163 [details]
proposed fix (diff against 2.10.9 code)

The bug probably exists in the 3.x code since the code in master appears to be the same as that in 2.10.9 in the relevant places in ComboBox.cs.
Comment 2 Stephen McConnel 2013-10-17 13:17:46 UTC
This is probably the same as https://bugzilla.xamarin.com/show_bug.cgi?id=4712 but with more details to explain why it's important and with a proposed fix.
Comment 3 Miguel de Icaza [MSFT] 2014-02-12 17:27:00 UTC
Setting priority to lowest, since Windows.Forms is no longer being developed actively.
Comment 4 eb1 2014-03-14 13:26:51 UTC
suggested fix is part of PR #943.