DialogHandler assumes it was started by DeckPicker, may crash otherwise

[mikehardy]

Reproduction Steps

1. Open AnkiDroid via a Reviewer-first pathway?
2. request file import?

Expected Result

Import dialog is shown

Actual Result

ClassCastException because import dialog is spawned from Reviewer somehow, instead of DeckPicker?

java.lang.ClassCastException: com.ichi2.anki.Reviewer cannot be cast to com.ichi2.anki.DeckPicker
at com.ichi2.anki.dialogs.DialogHandler.handleMessage(DialogHandler.java:82)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6501)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)

[mikehardy]

These are all the uses of the constant that could hit that case in the switch statement:

mike@isabela:~/work/AnkiDroid/Anki-Android (master) % grep -r 'new DialogHandler' *
AnkiDroid/src/main/java/com/ichi2/anki/AnkiActivity.java:    private DialogHandler mHandler = new DialogHandler(this);
mike@isabela:~/work/AnkiDroid/Anki-Android (master) % grep -r DIALOG_IMPORT_ADD_CONFIRM
AnkiDroid/src/main/java/com/ichi2/anki/dialogs/DialogHandler.java:            ((DeckPicker) mActivity.get()).showImportDialog(ImportDialog.DIALOG_IMPORT_ADD_CONFIRM, msgData.getString("importPath"));
AnkiDroid/src/main/java/com/ichi2/anki/dialogs/ImportDialog.java:    public static final int DIALOG_IMPORT_ADD_CONFIRM = 2;
AnkiDroid/src/main/java/com/ichi2/anki/dialogs/ImportDialog.java:                                    ((ImportDialogListener) getActivity()).showImportDialog(DIALOG_IMPORT_ADD_CONFIRM, importPath);
AnkiDroid/src/main/java/com/ichi2/anki/dialogs/ImportDialog.java:            case DIALOG_IMPORT_ADD_CONFIRM: {
AnkiDroid/src/main/java/com/ichi2/anki/DeckPicker.java:                || (id == ImportDialog.DIALOG_IMPORT_ADD_CONFIRM)

[mikehardy]

This just showed up with MyAccount cannot be cast to DeckPicker

https://couchdb.ankidroid.org/acralyzer/_design/acralyzer/index.html#/report-details/3c387372-bba0-49c7-973a-33eb17237fc3

java.lang.ClassCastException: com.ichi2.anki.MyAccount cannot be cast to com.ichi2.anki.DeckPicker
at com.ichi2.anki.dialogs.DialogHandler.handleMessage(DialogHandler.java:6)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:176)
at android.app.ActivityThread.main(ActivityThread.java:6635)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823)

[david-allison]

Theory: caused by a static in `DialogHandler` and `onResume()`

A new DialogHandler is spawned on each AnkiActivity:

Anki-Android/AnkiDroid/src/main/java/com/ichi2/anki/AnkiActivity.java

Line 46 in d3a6c61

private DialogHandler mHandler = new DialogHandler(this);

This references a static sStoredMessage

Anki-Android/AnkiDroid/src/main/java/com/ichi2/anki/dialogs/DialogHandler.java

Line 62 in f297f3c

private static Message sStoredMessage;

Which is read onResume.

Anki-Android/AnkiDroid/src/main/java/com/ichi2/anki/AnkiActivity.java

Line 81 in d3a6c61

mHandler.readMessage();

So: Store Message -> Change Activity -> Pause -> Resume -> Handle message on incorrect activity.

[david-allison]

Managed to trigger this. Don't have the exact steps. Debug Stack (with a few Huawei specific entries removed):

Caused by selecting a file in a file manager while AnkiDroid is running

Stack Trace

2020-04-02 08:07:36.794 20682-20682/? I/com.ichi2.anki: Late-enabling -Xcheck:jni
2020-04-02 08:07:36.843 20682-20682/? I/com.ichi2.anki: Reinit property: dalvik.vm.checkjni= false
2020-04-02 08:07:37.006 20682-20698/? I/HwApiCacheMangerEx: apicache path=/storage/emulated/0 state=mounted key=com.ichi2.anki#10262#256
2020-04-02 08:07:37.008 20682-20698/? I/HwApiCacheMangerEx: apicache path=/storage/emulated/0 state=mounted key=com.ichi2.anki#10262#0
2020-04-02 08:07:37.714 20682-20698/com.ichi2.anki I/AwareBitmapCacher: init processName:com.ichi2.anki pid=20682 uid=10262
2020-04-02 08:07:37.969 20682-20682/com.ichi2.anki I/ACRA: ACRA is disabled for com.ichi2.anki, initializing...
2020-04-02 08:07:38.122 20682-20682/com.ichi2.anki I/AnkiDroid: initialize()
2020-04-02 08:07:38.214 20682-20682/com.ichi2.anki W/com.ichi2.anki: Accessing hidden method Ldalvik/system/CloseGuard;->get()Ldalvik/system/CloseGuard; (light greylist, reflection)
2020-04-02 08:07:38.214 20682-20682/com.ichi2.anki W/com.ichi2.anki: Accessing hidden method Ldalvik/system/CloseGuard;->open(Ljava/lang/String;)V (light greylist, reflection)
2020-04-02 08:07:38.214 20682-20682/com.ichi2.anki W/com.ichi2.anki: Accessing hidden method Ldalvik/system/CloseGuard;->warnIfOpen()V (light greylist, reflection)
2020-04-02 08:07:38.225 20682-20682/com.ichi2.anki I/GoogleAnalyticsImpl: Not participating in analytics sample (sample percentage vs random: 10 50)
2020-04-02 08:07:38.228 20682-20682/com.ichi2.anki I/UsageAnalytics: setOptIn(): from false to false
2020-04-02 08:07:38.228 20682-20682/com.ichi2.anki I/GoogleAnalyticsImpl: Not participating in analytics sample (sample percentage vs random: 10 97)
2020-04-02 08:07:38.232 20682-20682/com.ichi2.anki I/UsageAnalytics: setDryRun(): true, warning dryRun is experimental
2020-04-02 08:07:38.260 20682-20682/com.ichi2.anki I/CompatV26: Creating notification channel with id/name: General Notifications/AnkiDroid
2020-04-02 08:07:38.271 20682-20682/com.ichi2.anki I/CompatV26: Creating notification channel with id/name: Synchronization/同步
2020-04-02 08:07:38.456 20682-20682/com.ichi2.anki I/CompatV26: Creating notification channel with id/name: Global Reminders/卡片到期
2020-04-02 08:07:38.460 20682-20682/com.ichi2.anki I/CompatV26: Creating notification channel with id/name: Deck Reminders/提醒
2020-04-02 08:07:38.529 20682-20682/com.ichi2.anki I/WebViewFactory: Loading com.android.chrome version 80.0.3987.149 (code 398714932)
2020-04-02 08:07:38.661 20682-20682/com.ichi2.anki I/cr_LibraryLoader: Loaded native library version number "80.0.3987.149"
2020-04-02 08:07:38.738 20682-20682/com.ichi2.anki I/CollectionHelper: openCollection: /storage/emulated/0/2/collection.anki2
2020-04-02 08:07:39.101 20682-20698/com.ichi2.anki E/MemoryLeakMonitorManager: MemoryLeakMonitor.jar is not exist!
2020-04-02 08:07:39.150 20682-20682/com.ichi2.anki I/HwApsImpl: APS: new HwApsImpl created
2020-04-02 08:07:39.168 20682-20682/com.ichi2.anki I/HwPhoneWindow: updateLayoutParamsColor false mSpecialSet=false, mForcedNavigationBarColor=false, navigationBarColor=0, mNavBarShow=false, mIsFloating=false
2020-04-02 08:07:39.170 20682-20682/com.ichi2.anki I/HwPhoneWindow: updateLayoutParamsColor true mSpecialSet=false, mForcedNavigationBarColor=false, navigationBarColor=ff000000, mNavBarShow=false, mIsFloating=false
2020-04-02 08:07:39.196 20682-20682/com.ichi2.anki I/ImportUtils: IntentHandler/ User requested to view a file
2020-04-02 08:07:39.214 20682-20682/com.ichi2.anki I/ImportUtils: Intent: Intent { act=android.intent.action.VIEW dat=content://com.huawei.hidisk.fileprovider/root/storage/emulated/0/Chinese_Sentences_and_audio_spoon_fed.apkg typ=application/* flg=0x13400003 cmp=com.ichi2.anki/.IntentHandler (has extras) }. Data: is_samba, open_type
2020-04-02 08:07:39.215 20682-20682/com.ichi2.anki I/ImportUtils: Attempting to read content from intent.
2020-04-02 08:07:42.179 20682-20781/com.ichi2.anki E/ZrHungImpl:  sendAppFreezeEvent failed!
2020-04-02 08:07:45.181 20682-20781/com.ichi2.anki E/ZrHungImpl:  sendAppFreezeEvent failed!
2020-04-02 08:07:48.128 20682-20682/com.ichi2.anki W/com.ichi2.anki: Accessing hidden method Landroid/graphics/drawable/Drawable;->getOpticalInsets()Landroid/graphics/Insets; (light greylist, linking)
2020-04-02 08:07:48.128 20682-20682/com.ichi2.anki W/com.ichi2.anki: Accessing hidden field Landroid/graphics/Insets;->left:I (light greylist, linking)
2020-04-02 08:07:48.128 20682-20682/com.ichi2.anki W/com.ichi2.anki: Accessing hidden field Landroid/graphics/Insets;->right:I (light greylist, linking)
2020-04-02 08:07:48.128 20682-20682/com.ichi2.anki W/com.ichi2.anki: Accessing hidden field Landroid/graphics/Insets;->top:I (light greylist, linking)
2020-04-02 08:07:48.128 20682-20682/com.ichi2.anki W/com.ichi2.anki: Accessing hidden field Landroid/graphics/Insets;->bottom:I (light greylist, linking)
2020-04-02 08:07:48.184 20682-20781/com.ichi2.anki E/ZrHungImpl:  sendAppFreezeEvent failed!
2020-04-02 08:07:48.480 20682-20682/com.ichi2.anki W/com.ichi2.anki: Accessing hidden method Landroid/widget/TextView;->getTextDirectionHeuristic()Landroid/text/TextDirectionHeuristic; (light greylist, linking)
2020-04-02 08:07:48.515 20682-20682/com.ichi2.anki W/com.ichi2.anki: Accessing hidden method Landroid/widget/PopupWindow;->setEpicenterBounds(Landroid/graphics/Rect;)V (light greylist, linking)
2020-04-02 08:07:48.518 20682-20682/com.ichi2.anki W/com.ichi2.anki: Accessing hidden method Landroid/widget/PopupWindow;->setClipToScreenEnabled(Z)V (light greylist, reflection)
2020-04-02 08:07:51.188 20682-20781/com.ichi2.anki E/ZrHungImpl:  sendAppFreezeEvent failed!
2020-04-02 08:07:52.184 20682-20682/com.ichi2.anki I/DeckTask: Cancelled task 30
2020-04-02 08:07:52.197 20682-20682/com.ichi2.anki I/DialogHandler: Dispatching persistent message: 2
2020-04-02 08:07:52.259 20682-20682/com.ichi2.anki I/Choreographer: Skipped 219 frames!  The application may be doing too much work on its main thread.
2020-04-02 08:07:52.296 20682-20682/com.ichi2.anki I/DeckTask: Cancelled task 30
2020-04-02 08:07:52.395 20682-20821/com.ichi2.anki I/Finder: _findCardsForCardBrowser() cancelled...
2020-04-02 08:07:52.723 20682-20682/com.ichi2.anki W/com.ichi2.anki: Accessing hidden method Landroid/graphics/drawable/DrawableContainer;->getOpticalInsets()Landroid/graphics/Insets; (light greylist, reflection)
2020-04-02 08:07:52.743 20682-20688/com.ichi2.anki I/com.ichi2.anki: Compiler allocated 4MB to compile void android.widget.TextView.<init>(android.content.Context, android.util.AttributeSet, int, int)
2020-04-02 08:07:52.815 20682-20682/com.ichi2.anki I/Choreographer: Skipped 31 frames!  The application may be doing too much work on its main thread.
2020-04-02 08:07:52.930 20682-20682/com.ichi2.anki I/DeckTask: Cancelled task 30
2020-04-02 08:07:52.978 20682-20682/com.ichi2.anki I/DeckTask: Cancelled task 30
2020-04-02 08:07:53.032 20682-20682/com.ichi2.anki W/ActivityThread: handleWindowVisibility: no activity for token android.os.BinderProxy@432f1b
2020-04-02 08:07:53.061 20682-20682/com.ichi2.anki I/ViewRootImpl: jank_removeInvalidNode jank list is null
2020-04-02 08:07:53.447 20682-20682/com.ichi2.anki I/DialogHandler: Handling Message: ImportAddDialog
2020-04-02 08:07:53.484 20682-20682/com.ichi2.anki E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.ichi2.anki, PID: 20682
    java.lang.ClassCastException: com.ichi2.anki.CardBrowser cannot be cast to com.ichi2.anki.DeckPicker
        at com.ichi2.anki.dialogs.DialogHandler.handleMessage(DialogHandler.java:85)
        at android.os.Handler.dispatchMessage(Handler.java:112)
        at android.os.Looper.loop(Looper.java:216)
        at android.app.ActivityThread.main(ActivityThread.java:7625)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:524)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:987)

[github-actions]

Hello 👋, this issue has been opened for more than 2 months with no activity on it. If the issue is still here, please keep in mind that we need community support and help to fix it! Just comment something like still searching for solutions and if you found one, please open a pull request! You have 7 days until this gets closed automatically

[david-allison]

This is my white whale. It happens a lot. I want to get a good reproduction case. I've added activity lifecycle logging to ACRA, so we can track this down

[david-allison]

DialogHandler needs to be rewritten using modern mechanisms. I've done a level of refactoring in d6bbea7, but not the rewrite.

Before this is done, we could trivially check whether DeckPicker is receiving the message, and if not, launching it.

Anki-Android/AnkiDroid/src/main/java/com/ichi2/anki/dialogs/DialogHandler.kt

Lines 37 to 43 in be62538

	override fun handleMessage(message: Message) {
	val msg = DialogHandlerMessage.fromMessage(message)
	UsageAnalytics.sendAnalyticsScreenView(msg.analyticName)
	Timber.i("Handling Message: %s", msg.analyticName)
	val deckPicker = mActivity.get() as DeckPicker
	msg.handleAsyncMessage(deckPicker)
	}