Chrome version is 56.0.2924.87

thanks this is the correct location.

attached the apk, haven't tried a nexus 9 yet, but nexus 5 running M on my desk doesn't show any issues, which matches report

Deleted: nomp-debug.apk 419 KB

nomp-debug.apk 419 KB Download

Thanks. I got an error report from a user that ran a different device, so I would guess any Nougat version would show the issue.

I also reproduced the issue on 7.0

Bo, I'm getting a crash on startup when opening the compiled app. The crash happens on n5x, n5, & n9, as well as across Android M and N with various WebView versions.

03-23 15:09:37.442 30251 30251 E AndroidRuntime: FATAL EXCEPTION: main
03-23 15:09:37.442 30251 30251 E AndroidRuntime: Process: se.nomp, PID: 30251
03-23 15:09:37.442 30251 30251 E AndroidRuntime: java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{se.nomp/com.selessia.nomp.web.WebViewActivity}: java.lang.ClassNotFoundException: Didn't find class "com.selessia.nomp.web.WebViewActivity" on path: DexPathList[[zip file "/data/app/se.nomp-1/base.apk"],nativeLibraryDirectories=[/data/app/se.nomp-1/lib/arm64, /vendor/lib64, /system/lib64]]
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2327)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        at android.app.ActivityThread.-wrap11(ActivityThread.java)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        at android.os.Handler.dispatchMessage(Handler.java:102)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        at android.os.Looper.loop(Looper.java:148)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        at android.app.ActivityThread.main(ActivityThread.java:5417)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        at java.lang.reflect.Method.invoke(Native Method)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
03-23 15:09:37.442 30251 30251 E AndroidRuntime: Caused by: java.lang.ClassNotFoundException: Didn't find class "com.selessia.nomp.web.WebViewActivity" on path: DexPathList[[zip file "/data/app/se.nomp-1/base.apk"],nativeLibraryDirectories=[/data/app/se.nomp-1/lib/arm64, /vendor/lib64, /system/lib64]]
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        at android.app.Instrumentation.newActivity(Instrumentation.java:1067)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2317)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        ... 9 more
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        Suppressed: java.lang.ClassNotFoundException: com.selessia.nomp.web.WebViewActivity
03-23 15:09:37.442 30251 30251 E AndroidRuntime:                at java.lang.Class.classForName(Native Method)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:                at java.lang.BootClassLoader.findClass(ClassLoader.java:781)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:                at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:                at java.lang.ClassLoader.loadClass(ClassLoader.java:504)
03-23 15:09:37.442 30251 30251 E AndroidRuntime:                ... 12 more
03-23 15:09:37.442 30251 30251 E AndroidRuntime:        Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack trace available

Am I missing something here? Or do you see the same crash?

The crash should not happen. Probably apk related. I can build another apk if that helps.

/Stefan

I've deployed the attached apk build to my device successfully.

./platform-tools/adb install /Users/stnor/AndroidStudioProjects/webview-issue-poc/nomp/build/outputs/apk/nomp-debug.apk
Success

And it runs fint without crashing.

Deleted: nomp-debug.apk 1.7 MB

nomp-debug.apk 1.7 MB Download

I notice its almost twice the size of boliu's build so maybe there is an issue with that apk. This should work fine though.

oh, I think the one I uploaded is a multi-apk and I uploaded only one..

Anyway. This is really odd. Seems like only the act of scrolling is updating the content of the page. Page works fine in chrome, and comparing trace of chrome and webview, both produces a single frame after clicking button to change language. Odd..

I'm happy you we're able to reproduce. Weirder still is that disabling HW-accel makes the code run just fine.

nah, that's not weird at all, they go in completely different paths

..on Nougat, albeit slow. I would love to have some better workaround. Any ideas on how to proceed?

given this is N and hardware only, I'm guessing this is somehow related to lifetime stuff. can't think of anything else that's like N-specific

> I would love to have some better workaround. Any ideas on how to proceed?

This is a webview bug. I guess use that workaround until there's a fix

+toby for the functor stuff. can't think of anything else that's N-specific..

oh, if you want to limit the workaround to N, then you can set the window flags at run time I think: https://developer.android.com/guide/topics/graphics/hardware-accel.html#controlling

Ok, thanks! I'll take a look at that.

This worked great:

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
            Log.d("NompWebView", "Android 7: Disabling hardware acceleration");
            webview.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
        }

Thanks.

huh, this only happens in your app, and not in our shell, and looking at your source code, I can't explain why... so odd

systrace shows android didn't call eglSwap o_O, maybe this is an android bug, not webview..

+jreck: under what circumstance would hwui call functor with kModeDraw, but not call eglSwapBuffers afterward that?

Trivial to reproduce this on N with apk in #8 above. Attached systrace. This would be the first DrawFrame on render thread.

Note this is a public bug.

Deleted: trace.html 8.3 MB

trace.html 8.3 MB View Download

The only reason we wouldn't call eglSwapBuffers after a kModeDraw is if we think nothing in the frame actually drew, which would be weird. Looking at HWUI's source, though, it looks like mHasDrawn doesn't get marked true when we hit webview's GL functor (oops).

Skimming through the app's source if you remove the android:windowBackground="@null" from the FullscreenTheme does it then work fine? Or if instead of setLayerType(LAYER_TYPE_SOFTWARE) you do setLayerType(LAYER_TYPE_HARDWARE), does that work?

If my theory is correct you just need to draw a single thing in the activity that's not a webview and then everything should work fine on N. A 1x1 rectangle at 0,0 would even work I think. If so the best workaround would be to either add a view that draws a dummy 1x1 rect to the base of your activity or subclass from webview, override onDraw() and draw a 1x1 rect before calling super.onDraw() for webview to cover it up with the actual contents.

I removed "<item name="android:windowBackground">@null</item>" and that make it work fine!

Setting LAYER_TYPE_HARDWARE on the webview also solves the problem independently. I wasn't expecting the layer type to be LAYER_TYPE_NONE since the         android:hardwareAccelerated="true"...

I'd recommend going with just removing the setting of windowBackground to @null, then. @null window backgrounds in the theme cause other subtle issues so it's better to just eliminate that. You don't want to use LAYER_TYPE_HARDWARE or LAYER_TYPE_SOFTWARE as a workaround usually, it hurts performance too much.

Ok, will do. Thanks.

John, is the mHasDrawn issue with the GL functor a bug we need to fix on the android side?

Proper fix will in be android (b/36602041). But we'll land a workaround in webview for N

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/340c180766d2857dab1a5a8a15df5c8e0c054f43

commit 340c180766d2857dab1a5a8a15df5c8e0c054f43
Author: boliu <boliu@chromium.org>
Date: Mon Mar 27 22:22:21 2017

android: Workaround libhwui N bug

Bug is that if functor is the only operation in a canvas, then that draw
will not swap. Workaround it by always painting a 1x1 pixel.

BUG= 704212 

Review-Url: https://codereview.chromium.org/2779773002
Cr-Commit-Position: refs/heads/master@{#459906}

[modify] https://crrev.com/340c180766d2857dab1a5a8a15df5c8e0c054f43/android_webview/java/src/org/chromium/android_webview/AwContents.java

Your change meets the bar and is auto-approved for M58. Please go ahead and merge the CL to branch 3029 manually. Please contact milestone owner if you have questions.
Owners: amineer@(Android), cmasso@(iOS), bhthompson@(ChromeOS), govind@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/451519fbb93ebf4c995e0fe0eb46890ff8252b5d

commit 451519fbb93ebf4c995e0fe0eb46890ff8252b5d
Author: Bo Liu <boliu@chromium.org>
Date: Mon Apr 03 13:16:49 2017

[Merge m58] android: Workaround libhwui N bug

Bug is that if functor is the only operation in a canvas, then that draw
will not swap. Workaround it by always painting a 1x1 pixel.

BUG= 704212 

Review-Url: https://codereview.chromium.org/2779773002
Cr-Commit-Position: refs/heads/master@{#459906}
(cherry picked from commit 340c180766d2857dab1a5a8a15df5c8e0c054f43)

Review-Url: https://codereview.chromium.org/2790123002 .
Cr-Commit-Position: refs/branch-heads/3029@{#542}
Cr-Branched-From: 939b32ee5ba05c396eef3fd992822fcca9a2e262-refs/heads/master@{#454471}

[modify] https://crrev.com/451519fbb93ebf4c995e0fe0eb46890ff8252b5d/android_webview/java/src/org/chromium/android_webview/AwContents.java

Fix verified on Nexus6P/Android 7.1.2, Monochrome: 59.0.3062.3. 

Verified on devices Nexus 9(MOB31V), Nexus 6(N2G47S)and LG V20(NRD90M) with 58.0.3029.54 , issue mentioned no longer reproducible.Thanks