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After being requested to share a video by Jason, a customer from the forums emailed into the support team a video of an issue they were seeing with refresh/repainting issues when hiding/showing controls using the IsVisible flag with the 1.3.x releases. They indicate that the issue was not present with the 1.2.x releases.
They have tried to put together a sample to repro the issue, but haven't been successful thus far.
The forum post in question is: http://forums.xamarin.com/discussion/comment/101413/#Comment_101413
Created attachment 9751 [details]
Sample IsVisible Control Rendering Issue
I've created a sample project with the issue. It happens in 1.3.x releases. It happens less with 1.3.4 Pre-release; however, it has kind of morphed on this latest pre-release to occur when toggling the IsVisible property on a custom control (ImageButton in sample project). In prior 1.3.x releases, once the control (Label, Image, ImageButton, etc.) was painted for the first time, it had no problem re-painting on subsequent toggles for the IsVisibleProperty. With the 1.3.4 pre-release, subsequent toggles of the IsVisibleProperty to true can result in re-painting issues for the custom control.
Created attachment 9759 [details]
IsVisible in a StackLayout painting wrong w 1.3.4
The attached solution was tested with 1.3.4 pre1. It shows that when a control in a stackLayout is toggled to invisible (bound to IsVisibleProperty), the stacklayout width goes to zero (even though other contents exist in the stacklayout that should be rendered). In the sample, click the refresh button to see the container widths rendered. Then click the collapse image in the right stackLayout...immediately, the entire stackLayout width is set to 0. Refresh to see that the StackLayout still has a view with width. Then click the Add right stack view back to get the view to be put back...note: if the view is put back with the expand/collapse image that is bound to IsVisible = false, the view will not render.
Only the Image should be invisible...not the entire stackLayout set to 0.
This is resolved completely now in 1.3.4-pre4
1.3.4-pre4 is looking better and also working better on Android too.
I have confirmed that this issue seems to be mostly resolved with 1.3.4-pre4. It looks like buttons are still having problems re-rendering when going to IsVisible=true from a bound value (sometimes). We're also experiencing it on a custom ImageButton (that's based on a button); however, it's also happening on standard button controls as well.
I'll submit another IsVisibleTest2-5 project to show the issue. Just set the count of toggles to 1 and click to toggle from visible-to invisible-to visible. After a while I was able to see the problem in iOS 8.1 iPad Retina simulator.
Thanks for your quick response to this issue,
Created attachment 9830 [details]
IsVisibleTest2-5 showing button IsVisible fail
As promised, here's the sample.
I have tested this out with Forms 1.3.4 final and have been able to reproduce the issue Wayne is seeing using the test project in comment #c6.
Thank you will look into it.
Updating to 1.4.2 seems to resolve the issue. Please re-open if you can still reproduce the problem on 1.4.2.
Thank you for providing the reproduction.
Still having issues with 1.4.2 on iOS.
I have images (used as buttons) displayed or not according to the state of my UI.
Sometimes the image supposed to be displayed is just not.