Black screen

[spacepluk]

Sometimes the app screen turns to black. It's easy to reproduce if you go the app switcher and back several times. Eventually the app turns black and the only way to fix it is killing it. I'm not sure if it's related but I get a lot of these through logcat:

W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.
W/AwContents(23278): nativeOnDraw failed; clearing to background color.

I'm getting this on a Nexus 5 with the latest updates, and a Nexus 7 (old version) with Cyanogenmod nightlies.

[ludei]

Hello spacepluk

I cannot reproduce the problem, I've tried with my Nexus 4 and it works correctly doing this:

• I've created an app that points to http://www.polymer-project.org/apps/topeka/ (window.location.href='http://www.polymer-project.org/apps/topeka/')
• I've been trying for five minutes this -> open the app switcher -> go to the background -> return to the app.

After several tests, the app has been running correctly.... I have more devices at the office so I'll try to reproduce the problem on them.

And yes, the nativeOnDraw could be related to the problem.

[spacepluk]

Hmm, I'm using a WebGL canvas in the webview maybe is that what is triggering the problem.

Try pointing your application to this url (http://www.goodboydigital.com/pixijs/bunnymark/), and then do the dancing with the switcher. I hope it helps.

[ludei]

I've tried with that url and it also works correctly, I'll try with other devices then.

Thanks

[ludei]

Got it!

I/chromium(20593): [20593:20593:0702/115306:34244215909:INFO:CONSOLE(1)] "exception firing resume event from native", source: (1) W/AwContents(20593): nativeOnDraw failed; clearing to background color.

and I can see the black screen, we are working on this task so I'll keep you informed.

[spacepluk]

Great! Thank you! :)

[ludei]

Hello spacepluk

Please download this .zip https://dl.dropboxusercontent.com/u/22509177/apks/HelloCordova-debug.apk.zip, extract it and install the apk: $ adb install -r HelloCordova-debug.apk

Does this apk solves your problem?

[spacepluk]

Excellent! This fixes the problem with the black screen :) Also the switching is a lot smoother than before :+1: :+1:

I have no idea if this is related but, when the app starts for the first time there's a strange artifact on top of the canvas. It's a white box that flashes like it's rendering every two frames or so. Once I go to the switcher and back it goes away :?

Also, I'm still getting the nativeOnDraw failed logs.

The same example in Chrome Beta from GooglePlay doesn't have the artifact, but this is v36 I think.

I only see the artifact in my Nexus 7, because in the Nexus 5 the canvas covers the whole screen so I can't tell if it's there or not. I managed to take a picture of it:

[ludei]

mmmm, I'll close this issue in the next release of the Webview+ and will open another one with that :) thank you!

[spacepluk]

Heheh, ok, thanks!

[Behrouz-m]

I have this issue with default Android webview. How did you fix that ?

[kubido]

@ray-pixar +1, still can't find how to fix this issue

[cyrillegr]

Same issue with the default android webview on Kitkat 4.4.4. How did you fix that ? Thanks