Bug 39464 - [UWP Forms] Rounded Button Corners do not render in Forms (but do in native UWP)
Summary: [UWP Forms] Rounded Button Corners do not render in Forms (but do in native UWP)
Alias: None
Product: Forms
Classification: Xamarin
Component: Windows ()
Version: 2.0.0
Hardware: PC Mac OS
: Normal normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2016-03-08 20:31 UTC by Matthew Regul
Modified: 2016-04-26 20:11 UTC (History)
8 users (show)

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

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Description Matthew Regul 2016-03-08 20:31:11 UTC
== Overview: =================================
Rounded button corners do not work within UWP Forms, but will work in a native UWP app.

Android - https://cloud.githubusercontent.com/assets/8008527/13614328/f5d9d3ac-e53d-11e5-96ee-43c0d745a6dc.png
Windows - https://cloud.githubusercontent.com/assets/8008527/13614379/2b20d7a4-e53e-11e5-9a15-7ae080b49e39.png

[See private note for more details]
Comment 2 philip.o 2016-03-08 20:38:58 UTC
The issues is that is impossible to make rounded corners even if using templates in the renderer.

I have the effect I want on a native UWP app here:
If I load this style in a renderer in a Forms app it still has the nasty corners (in the color of the button background).
When forms creates the button it paints the entire rectangle of the button the specified background color. There is nothing from the renderer I can do to clear that color. So no matter what changes I make to the native Control in my renderer I cannot get rid of the original color set by Forms.

public class CustomButtonRenderer : ButtonRenderer

protected override void OnElementChanged(ElementChangedEventArgs<Xamarin.Forms.Button> e)
var button = (RoundedButton)e.NewElement;
if (Control != null)
button.SizeChanged += OnSizeChanged;

private void OnSizeChanged(object sender, EventArgs e)
var button = (RoundedButton)sender;
Control.Style = (Style)Application.Current.Resources["RoundedButtonStyle"];
button.SizeChanged -= OnSizeChanged;

Comment 7 Rui Marinho 2016-04-01 10:11:47 UTC
Should be fixed in 2.2-pre1