CB-13094: (android) Don't show splash when activity being finished

[SharUpOff]

Platforms affected

• android

What does this PR do?

• Prevent to show the splash dialog if the activity is in the process of finishing referenced to (android docs)

What testing has been done on this change?

• build and runtime is ok
• I think there are not need special tests

Checklist

• Reported an issue in the JIRA database
• Commit message follows the format: "CB-3232: (android) Fix bug with resolving file paths", where CB-xxxx is the JIRA ID & "android" is the platform affected.
• Added automated test coverage as appropriate for this change.

[filmaj]

In theory this looks fine to me.

Is there a situation where the splash screen is shown during this "finishing" phase? Just wondering how I can reproduce this to test it locally.

[SharUpOff]

I got it so:

window.addEventListener('beforeunload', function()
{
    navigator.splashscreen.show();
});

I show splash when reload my application without restarting cordova in some cases (language switching, debug mode, etc). Closing by "back" button fires "beforeunload" (to "about:blank" i think) and showing splash in same time activity being finished. Also i use crosswalk, maybe it fires "beforeunload", not the native WebView.

Trace here:

FATAL EXCEPTION: main
Process: scat.su.calltaxi, PID: 16999
android.view.WindowManager$BadTokenException: Unable to add window – token android.os.BinderProxy@5d0142d is not valid; is your activity running?
at android.view.ViewRootImpl.setView(ViewRootImpl.java:567)
at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:310)
at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:86)
at android.app.Dialog.show(Dialog.java:326)
at org.apache.cordova.splashscreen.SplashScreen$5.run(SplashScreen.java:318)
at android.app.Activity.runOnUiThread(Activity.java:5558)
at org.apache.cordova.splashscreen.SplashScreen.showSplashScreen(SplashScreen.java:281)
at org.apache.cordova.splashscreen.SplashScreen.onMessage(SplashScreen.java:189)
at org.apache.cordova.PluginManager.postMessage(PluginManager.java:312)
at org.apache.cordova.CordovaWebViewImpl.postMessage(CordovaWebViewImpl.java:377)
at org.apache.cordova.splashscreen.SplashScreen$3.run(SplashScreen.java:169)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5517)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

[filmaj]

Ah, great! Thanks for describing that. I will take a look at that.

[filmaj]

OK, I've been able to reproduce the behaviour - sort of. In my case, it wasn't that the my app showed the splashscreen, but that the app crashed while exiting!

My test app was a fresh cordova project with cordova-android 6.2.3 and cordova-plugin-splashscreen 4.0.3 added. I added nothing to the default cordova app code other than attaching splashscreen.show() to the beforeunload method, as per your above comment.

Here's my stack trace:

07-26 12:59:40.652  9214  9214 D CordovaActivity: Stopped the activity.
07-26 12:59:40.652  9214  9214 D CordovaActivity: CordovaActivity.onDestroy()
07-26 12:59:40.653  9214  9214 D CordovaWebViewImpl: >>> loadUrl(about:blank)
07-26 12:59:40.663  9214  9214 W cr_AwContents: WebView.destroy() called while WebView is still attached to window.
07-26 12:59:40.726  1162  5658 W WindowManager: Attempted to add application window with unknown token Token{760cced ActivityRecord{f0b0f04 u0 io.cordova.hellocordova/.MainActivity t129 f}}.  Aborting.
07-26 12:59:40.727  9214  9214 D AndroidRuntime: Shutting down VM
--------- beginning of crash
07-26 12:59:40.728  9214  9214 E AndroidRuntime: FATAL EXCEPTION: main
07-26 12:59:40.728  9214  9214 E AndroidRuntime: Process: io.cordova.hellocordova, PID: 9214
07-26 12:59:40.728  9214  9214 E AndroidRuntime: android.view.WindowManager$BadTokenException: Unable to add window -- token android.os.BinderProxy@1012df7 is not valid; is your activity running?
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at android.view.ViewRootImpl.setView(ViewRootImpl.java:679)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:342)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:93)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at android.app.Dialog.show(Dialog.java:329)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at org.apache.cordova.splashscreen.SplashScreen$5.run(SplashScreen.java:318)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at android.app.Activity.runOnUiThread(Activity.java:5869)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at org.apache.cordova.splashscreen.SplashScreen.showSplashScreen(SplashScreen.java:281)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at org.apache.cordova.splashscreen.SplashScreen.onMessage(SplashScreen.java:189)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at org.apache.cordova.PluginManager.postMessage(PluginManager.java:312)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at org.apache.cordova.CordovaWebViewImpl.postMessage(CordovaWebViewImpl.java:377)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at org.apache.cordova.splashscreen.SplashScreen$3.run(SplashScreen.java:169)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at android.os.Handler.handleCallback(Handler.java:751)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at android.os.Handler.dispatchMessage(Handler.java:95)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at android.os.Looper.loop(Looper.java:154)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at android.app.ActivityThread.main(ActivityThread.java:6121)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at java.lang.reflect.Method.invoke(Native Method)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:889)
07-26 12:59:40.728  9214  9214 E AndroidRuntime: 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:779)

This was on a Google Pixel running Android 7.1.2.

Next up I'll test out your patch and see how the behaviour differs.

FYI @infil00p.

[filmaj]

And @SharUpOff your intuition is confirmed: the logcat logs show that after pressing the back button in my app after loading it up, Cordova tries to load about:blank:

07-26 12:59:40.652  9214  9214 D CordovaActivity: Stopped the activity.
07-26 12:59:40.652  9214  9214 D CordovaActivity: CordovaActivity.onDestroy()
07-26 12:59:40.653  9214  9214 D CordovaWebViewImpl: >>> loadUrl(about:blank)

[infil00p]

Going to about:blank is done as a garbage collection technique before closing out the WebView entirely so that the memory is freed. There's a hilarious TODO here saying that it shouldn't destroy the WebView until about:blank is done loading.

But yeah, I agree with the fix. The Splashscreen shouldn't try to attach a UI element to the Activity while the Activity is basically killing itself on a backbutton, or some other exit event, and that's clearly what's causing this behaviour.

Of course, if we never made this a plugin in the first place, we wouldn't have such a weird disconnect between this plugin and the platform code, so there is that. This is why we're looking at wrapping this plugin back into the platform.

[filmaj]

Confirmed that this patch fixes the crash. Merged it in.

Thanks for the contribution @SharUpOff! + on your first ever GitHub PR, too

[SharUpOff]

@filmaj, thank you for the prompt response! (: