Fix memory leaks and add documentation

[TobiGr]

What is it?

• Bugfix (user facing)
• Feature (user facing)
• Codebase improvement (dev facing)
• Meta improvement to the project (dev facing)

Description of the changes in your PR

Fixed three memory leaks and added documentation to BaseFragment.initViews() and BaseFragment.initListeners().
The leaks were detected in the channel tabs PR APK, but also occur to the current dev version.
LeakCanary warnings for each leak:

BaseFragment

┬───
│ GC Root: Global variable in native code
│
├─ android.database.ContentObserver$Transport instance
│    Leaking: NO (VideoDetailFragment↓ is not leaking)
│    ↓ ContentObserver$Transport.mContentObserver
├─ org.schabi.newpipe.fragments.detail.VideoDetailFragment$1 instance
│    Leaking: NO (VideoDetailFragment↓ is not leaking)
│    Anonymous subclass of android.database.ContentObserver
│    ↓ VideoDetailFragment$1.this$0
├─ org.schabi.newpipe.fragments.detail.VideoDetailFragment instance
│    Leaking: NO (MainActivity↓ is not leaking and Fragment#mFragmentManager is
│    not null)
│    activity instance of org.schabi.newpipe.MainActivity with mDestroyed =
│    false
│    ↓ BaseFragment.activity
├─ org.schabi.newpipe.MainActivity instance
│    Leaking: NO (BookmarkFragment↓ is not leaking and Activity#mDestroyed is
│    false)
│    mApplication instance of org.schabi.newpipe.DebugApp
│    mBase instance of androidx.appcompat.view.ContextThemeWrapper
│    ↓ ComponentActivity.mActivityResultRegistry
├─ androidx.activity.ComponentActivity$2 instance
│    Leaking: NO (BookmarkFragment↓ is not leaking)
│    Anonymous subclass of androidx.activity.result.ActivityResultRegistry
│    this$0 instance of org.schabi.newpipe.MainActivity with mDestroyed = false
│    ↓ ActivityResultRegistry.mKeyToCallback
├─ java.util.HashMap instance
│    Leaking: NO (BookmarkFragment↓ is not leaking)
│    ↓
│    HashMap["FragmentManager:a9522914-3ef2-44fa-8348-a154d73d1f3d:StartActivity
│    ForResult"]
├─ androidx.activity.result.ActivityResultRegistry$CallbackAndContract instance
│    Leaking: NO (BookmarkFragment↓ is not leaking)
│    ↓ ActivityResultRegistry$CallbackAndContract.mCallback
├─ androidx.fragment.app.FragmentManager$7 instance
│    Leaking: NO (BookmarkFragment↓ is not leaking)
│    Anonymous class implementing androidx.activity.result.
│    ActivityResultCallback
│    ↓ FragmentManager$7.this$0
├─ androidx.fragment.app.FragmentManagerImpl instance
│    Leaking: NO (BookmarkFragment↓ is not leaking)
│    ↓ FragmentManager.mParent
├─ org.schabi.newpipe.local.bookmark.BookmarkFragment instance
│    Leaking: NO (Fragment#mFragmentManager is not null)
│    activity instance of org.schabi.newpipe.MainActivity with mDestroyed =
│    false
│    ↓ BaseStateFragment.emptyStateView
│                        ~~~~~~~~~~~~~~
├─ android.widget.LinearLayout instance
│    Leaking: UNKNOWN
│    Retaining 4.6 kB in 62 objects
│    View not part of a window view hierarchy
│    View.mAttachInfo is null (view detached)
│    View.mID = R.id.empty_state_view
│    View.mWindowAttachCount = 1
│    mContext instance of org.schabi.newpipe.MainActivity with mDestroyed =
│    false
│    ↓ View.mParent
│           ~~~~~~~
╰→ android.widget.RelativeLayout instance
​     Leaking: YES (ObjectWatcher was watching this because org.schabi.newpipe.
​     local.bookmark.BookmarkFragment received Fragment#onDestroyView()
​     callback (references to its views should be cleared to prevent leaks))
​     Retaining 37.2 kB in 752 objects
​     key = a2cfc288-352e-46cf-acd5-aeeb81b3543a
​     watchDurationMillis = 5653
​     retainedDurationMillis = 653
​     View not part of a window view hierarchy
​     View.mAttachInfo is null (view detached)
​     View.mWindowAttachCount = 1
​     mContext instance of org.schabi.newpipe.MainActivity with mDestroyed =
​     false

METADATA

Build.VERSION.SDK_INT: 33
Build.MANUFACTURER: Google
LeakCanary version: 2.12
App process name: org.schabi.newpipe.debug.channeltabs
Class count: 29937
Instance count: 302474
Primitive array count: 178526
Object array count: 46362
Thread count: 70
Heap total bytes: 39375594
Bitmap count: 37
Bitmap total bytes: 6990037
Large bitmap count: 0
Large bitmap total bytes: 0
Db 1: open /data/user/0/org.schabi.newpipe.debug.channeltabs/databases/newpipe.
db
Db 2: open /data/user/0/org.schabi.newpipe.debug.
channeltabs/databases/exoplayer_internal.db
Db 3: open /data/user/0/org.schabi.newpipe.debug.channeltabs/no_backup/androidx.
work.workdb
Stats: LruCache[maxSize=3000,hits=145229,misses=299165,hitRate=32%]
RandomAccess[bytes=16106429,reads=299165,travel=147301735717,range=44855238,size
=56086672]
Analysis duration: 8867 ms

MainFragment.binding

┬───
│ GC Root: Global variable in native code
│
├─ android.database.ContentObserver$Transport instance
│    Leaking: NO (VideoDetailFragment↓ is not leaking)
│    ↓ ContentObserver$Transport.mContentObserver
├─ org.schabi.newpipe.fragments.detail.VideoDetailFragment$1 instance
│    Leaking: NO (VideoDetailFragment↓ is not leaking)
│    Anonymous subclass of android.database.ContentObserver
│    ↓ VideoDetailFragment$1.this$0
├─ org.schabi.newpipe.fragments.detail.VideoDetailFragment instance
│    Leaking: NO (MainFragment↓ is not leaking and Fragment#mFragmentManager is
│    not null)
│    activity instance of org.schabi.newpipe.MainActivity with mDestroyed =
│    false
│    ↓ Fragment.mFragmentManager
├─ androidx.fragment.app.FragmentManagerImpl instance
│    Leaking: NO (MainFragment↓ is not leaking)
│    ↓ FragmentManager.mFragmentStore
├─ androidx.fragment.app.FragmentStore instance
│    Leaking: NO (MainFragment↓ is not leaking)
│    ↓ FragmentStore.mActive
├─ java.util.HashMap instance
│    Leaking: NO (MainFragment↓ is not leaking)
│    ↓ HashMap["a7644fcc-e730-4ce5-a2c2-2930b43e4070"]
├─ androidx.fragment.app.FragmentStateManager instance
│    Leaking: NO (MainFragment↓ is not leaking)
│    ↓ FragmentStateManager.mFragment
├─ org.schabi.newpipe.fragments.MainFragment instance
│    Leaking: NO (Fragment#mFragmentManager is not null)
│    activity instance of org.schabi.newpipe.MainActivity with mDestroyed =
│    false
│    ↓ MainFragment.binding
│                   ~~~~~~~
├─ org.schabi.newpipe.databinding.FragmentMainBinding instance
│    Leaking: UNKNOWN
│    Retaining 35.6 kB in 675 objects
│    ↓ FragmentMainBinding.rootView
│                          ~~~~~~~~
╰→ android.widget.RelativeLayout instance
​     Leaking: YES (ObjectWatcher was watching this because org.schabi.newpipe.
​     fragments.MainFragment received Fragment#onDestroyView() callback
​     (references to its views should be cleared to prevent leaks))
​     Retaining 2.5 kB in 61 objects
​     key = 7cafed14-babd-4f63-b765-2b8f8b126b51
​     watchDurationMillis = 5653
​     retainedDurationMillis = 653
​     View not part of a window view hierarchy
​     View.mAttachInfo is null (view detached)
​     View.mWindowAttachCount = 1
​     mContext instance of org.schabi.newpipe.MainActivity with mDestroyed =
​     false

METADATA

Build.VERSION.SDK_INT: 33
Build.MANUFACTURER: Google
LeakCanary version: 2.12
App process name: org.schabi.newpipe.debug.channeltabs
Class count: 29937
Instance count: 302474
Primitive array count: 178526
Object array count: 46362
Thread count: 70
Heap total bytes: 39375594
Bitmap count: 37
Bitmap total bytes: 6990037
Large bitmap count: 0
Large bitmap total bytes: 0
Db 1: open /data/user/0/org.schabi.newpipe.debug.channeltabs/databases/newpipe.
db
Db 2: open /data/user/0/org.schabi.newpipe.debug.
channeltabs/databases/exoplayer_internal.db
Db 3: open /data/user/0/org.schabi.newpipe.debug.channeltabs/no_backup/androidx.
work.workdb
Stats: LruCache[maxSize=3000,hits=145229,misses=299165,hitRate=32%]
RandomAccess[bytes=16106429,reads=299165,travel=147301735717,range=44855238,size
=56086672]
Analysis duration: 8867 ms

SubscriptionFragment

┬───
│ GC Root: Thread object
│
├─ android.os.HandlerThread instance
│    Leaking: NO (PathClassLoader↓ is not leaking)
│    Thread name: 'LeakCanary-Heap-Dump'
│    ↓ Thread.contextClassLoader
├─ dalvik.system.PathClassLoader instance
│    Leaking: NO (InternalLeakCanary↓ is not leaking and A ClassLoader is never
│    leaking)
│    ↓ ClassLoader.runtimeInternalObjects
├─ java.lang.Object[] array
│    Leaking: NO (InternalLeakCanary↓ is not leaking)
│    ↓ Object[22]
├─ leakcanary.internal.InternalLeakCanary class
│    Leaking: NO (MainActivity↓ is not leaking and a class is never leaking)
│    ↓ static InternalLeakCanary.resumedActivity
├─ org.schabi.newpipe.MainActivity instance
│    Leaking: NO (SubscriptionFragment↓ is not leaking and Activity#mDestroyed
│    is false)
│    mApplication instance of org.schabi.newpipe.DebugApp
│    mBase instance of androidx.appcompat.view.ContextThemeWrapper
│    ↓ ComponentActivity.mActivityResultRegistry
├─ androidx.activity.ComponentActivity$2 instance
│    Leaking: NO (SubscriptionFragment↓ is not leaking)
│    Anonymous subclass of androidx.activity.result.ActivityResultRegistry
│    this$0 instance of org.schabi.newpipe.MainActivity with mDestroyed = false
│    ↓ ActivityResultRegistry.mKeyToCallback
├─ java.util.HashMap instance
│    Leaking: NO (SubscriptionFragment↓ is not leaking)
│    ↓
│    HashMap["FragmentManager:702cd362-5180-4953-ad5e-c175b0bbae41:StartIntentSe
│    nderForResult"]
├─ androidx.activity.result.ActivityResultRegistry$CallbackAndContract instance
│    Leaking: NO (SubscriptionFragment↓ is not leaking)
│    ↓ ActivityResultRegistry$CallbackAndContract.mCallback
├─ androidx.fragment.app.FragmentManager$8 instance
│    Leaking: NO (SubscriptionFragment↓ is not leaking)
│    Anonymous class implementing androidx.activity.result.
│    ActivityResultCallback
│    ↓ FragmentManager$8.this$0
├─ androidx.fragment.app.FragmentManagerImpl instance
│    Leaking: NO (SubscriptionFragment↓ is not leaking)
│    ↓ FragmentManager.mParent
├─ org.schabi.newpipe.local.subscription.SubscriptionFragment instance
│    Leaking: NO (Fragment#mFragmentManager is not null)
│    activity instance of org.schabi.newpipe.MainActivity with mDestroyed =
│    false
│    ↓ SubscriptionFragment._binding
│                           ~~~~~~~~
├─ org.schabi.newpipe.databinding.FragmentSubscriptionBinding instance
│    Leaking: UNKNOWN
│    Retaining 72 B in 3 objects
│    ↓ FragmentSubscriptionBinding.rootView
│                                  ~~~~~~~~
╰→ android.widget.RelativeLayout instance
​     Leaking: YES (ObjectWatcher was watching this because org.schabi.newpipe.
​     local.subscription.SubscriptionFragment received Fragment#onDestroyView()
​     callback (references to its views should be cleared to prevent leaks))
​     Retaining 4.1 kB in 88 objects
​     key = 4e1921b2-3398-473a-a79b-53ca1fdfa44c
​     watchDurationMillis = 5557
​     retainedDurationMillis = 557
​     View not part of a window view hierarchy
​     View.mAttachInfo is null (view detached)
​     View.mWindowAttachCount = 1
​     mContext instance of org.schabi.newpipe.MainActivity with mDestroyed =
​     false

METADATA

Build.VERSION.SDK_INT: 33
Build.MANUFACTURER: Google
LeakCanary version: 2.12
App process name: org.schabi.newpipe.debug.channeltabs
Class count: 27581
Instance count: 229859
Primitive array count: 146666
Object array count: 34391
Thread count: 56
Heap total bytes: 30822107
Bitmap count: 11
Bitmap total bytes: 5314931
Large bitmap count: 0
Large bitmap total bytes: 0
Db 1: open /data/user/0/org.schabi.newpipe.debug.channeltabs/databases/newpipe.
db
Db 2: open /data/user/0/org.schabi.newpipe.debug.channeltabs/no_backup/androidx.
work.workdb
Stats: LruCache[maxSize=3000,hits=125879,misses=227557,hitRate=35%]
RandomAccess[bytes=11728626,reads=227557,travel=86156950881,range=37027951,size=
45095731]
Analysis duration: 7243 ms

Note

I sometimes get an undeliverable Exception thrown with this APK. Not sure if this is related:

Details

RxJavaPlugins.ErrorHandler called with -> : throwable = [io.reactivex.rxjava3.exceptions.UndeliverableException]
2023-08-29 19:43:01.593  4823-4859  ACRA                    org....newpipe.debug.fixmemoryleaks  E  ACRA caught a ParsingException for org.schabi.newpipe.debug.fixmemoryleaks
                                                                                                    org.schabi.newpipe.extractor.exceptions.ParsingException: Could not store JavaScript player
                                                                                                    	at org.schabi.newpipe.extractor.services.youtube.extractors.YoutubeStreamExtractor.storePlayerJs(YoutubeStreamExtractor.java:1117)
                                                                                                    	at org.schabi.newpipe.extractor.services.youtube.extractors.YoutubeStreamExtractor.initStsFromPlayerJsIfNeeded(YoutubeStreamExtractor.java:1185)
                                                                                                    	at org.schabi.newpipe.extractor.services.youtube.extractors.YoutubeStreamExtractor.onFetchPage(YoutubeStreamExtractor.java:817)
                                                                                                    	at org.schabi.newpipe.extractor.Extractor.fetchPage(Extractor.java:60)
                                                                                                    	at org.schabi.newpipe.extractor.stream.StreamInfo.getInfo(StreamInfo.java:78)
                                                                                                    	at org.schabi.newpipe.extractor.stream.StreamInfo.getInfo(StreamInfo.java:73)
                                                                                                    	at org.schabi.newpipe.util.ExtractorHelper.lambda$getStreamInfo$3(ExtractorHelper.java:119)
                                                                                                    	at org.schabi.newpipe.util.ExtractorHelper$$ExternalSyntheticLambda8.call(Unknown Source:4)
                                                                                                    	at io.reactivex.rxjava3.internal.operators.single.SingleFromCallable.subscribeActual(SingleFromCallable.java:43)
                                                                                                    	at io.reactivex.rxjava3.core.Single.subscribe(Single.java:4855)
                                                                                                    	at io.reactivex.rxjava3.internal.operators.single.SingleDoOnSuccess.subscribeActual(SingleDoOnSuccess.java:35)
                                                                                                    	at io.reactivex.rxjava3.core.Single.subscribe(Single.java:4855)
                                                                                                    	at io.reactivex.rxjava3.internal.operators.maybe.MaybeFromSingle.subscribeActual(MaybeFromSingle.java:41)
                                                                                                    	at io.reactivex.rxjava3.core.Maybe.subscribe(Maybe.java:5377)
                                                                                                    	at io.reactivex.rxjava3.internal.operators.maybe.MaybeConcatArray$ConcatMaybeObserver.drain(MaybeConcatArray.java:153)
                                                                                                    	at io.reactivex.rxjava3.internal.operators.maybe.MaybeConcatArray$ConcatMaybeObserver.request(MaybeConcatArray.java:78)
                                                                                                    	at io.reactivex.rxjava3.internal.operators.flowable.FlowableElementAtMaybe$ElementAtSubscriber.onSubscribe(FlowableElementAtMaybe.java:66)
                                                                                                    	at io.reactivex.rxjava3.internal.operators.maybe.MaybeConcatArray.subscribeActual(MaybeConcatArray.java:42)
                                                                                                    	at io.reactivex.rxjava3.core.Flowable.subscribe(Flowable.java:16013)
                                                                                                    	at io.reactivex.rxjava3.internal.operators.flowable.FlowableElementAtMaybe.subscribeActual(FlowableElementAtMaybe.java:36)
                                                                                                    	at io.reactivex.rxjava3.core.Maybe.subscribe(Maybe.java:5377)
                                                                                                    	at io.reactivex.rxjava3.internal.operators.maybe.MaybeToSingle.subscribeActual(MaybeToSingle.java:46)
                                                                                                    	at io.reactivex.rxjava3.core.Single.subscribe(Single.java:4855)
                                                                                                    	at io.reactivex.rxjava3.internal.operators.single.SingleSubscribeOn$SubscribeOnObserver.run(SingleSubscribeOn.java:89)
                                                                                                    	at io.reactivex.rxjava3.core.Scheduler$DisposeTask.run(Scheduler.java:644)
                                                                                                    	at io.reactivex.rxjava3.internal.schedulers.ScheduledRunnable.run(ScheduledRunnable.java:65)
                                                                                                    	at io.reactivex.rxjava3.internal.schedulers.ScheduledRunnable.call(ScheduledRunnable.java:56)
                                                                                                    	at java.util.concurrent.FutureTask.run(FutureTask.java:264)
                                                                                                    	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:307)
                                                                                                    	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1137)
                                                                                                    	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:637)
                                                                                                    	at java.lang.Thread.run(Thread.java:1012)
                                                                                                    Caused by: org.schabi.newpipe.extractor.exceptions.ParsingException: Embedded info did not provide YouTube player js url
                                                                                                    	at org.schabi.newpipe.extractor.services.youtube.YoutubeJavaScriptExtractor.extractJavaScriptUrl(YoutubeJavaScriptExtractor.java:116)
                                                                                                    	at org.schabi.newpipe.extractor.services.youtube.YoutubeJavaScriptExtractor.extractJavaScriptCode(YoutubeJavaScriptExtractor.java:46)
                                                                                                    	at org.schabi.newpipe.extractor.services.youtube.YoutubeJavaScriptExtractor.extractJavaScriptCode(YoutubeJavaScriptExtractor.java:65)
                                                                                                    	at org.schabi.newpipe.extractor.services.youtube.extractors.YoutubeStreamExtractor.storePlayerJs(YoutubeStreamExtractor.java:1115)
                                                                                                    	at org.schabi.newpipe.extractor.services.youtube.extractors.YoutubeStreamExtractor.initStsFromPlayerJsIfNeeded(YoutubeStreamExtractor.java:1185) 
                                                                                                    	at org.schabi.newpipe.extractor.services.youtube.extractors.YoutubeStreamExtractor.onFetchPage(YoutubeStreamExtractor.java:817) 
                                                                                                    	at org.schabi.newpipe.extractor.Extractor.fetchPage(Extractor.java:60) 
                                                                                                    	at org.schabi.newpipe.extractor.stream.StreamInfo.getInfo(StreamInfo.java:78) 
                                                                                                    	at org.schabi.newpipe.extractor.stream.StreamInfo.getInfo(StreamInfo.java:73) 
                                                                                                    	at org.schabi.newpipe.util.ExtractorHelper.lambda$getStreamInfo$3(ExtractorHelper.java:119) 
                                                                                                    	at org.schabi.newpipe.util.ExtractorHelper$$ExternalSyntheticLambda8.call(Unknown Source:4) 
                                                                                                    	at io.reactivex.rxjava3.internal.operators.single.SingleFromCallable.subscribeActual(SingleFromCallable.java:43) 
                                                                                                    	at io.reactivex.rxjava3.core.Single.subscribe(Single.java:4855) 
                                                                                                    	at io.reactivex.rxjava3.internal.operators.single.SingleDoOnSuccess.subscribeActual(SingleDoOnSuccess.java:35) 
                                                                                                    	at io.reactivex.rxjava3.core.Single.subscribe(Single.java:4855) 
                                                                                                    	at io.reactivex.rxjava3.internal.operators.maybe.MaybeFromSingle.subscribeActual(MaybeFromSingle.java:41) 
                                                                                                    	at io.reactivex.rxjava3.core.Maybe.subscribe(Maybe.java:5377) 
                                                                                                    	at io.reactivex.rxjava3.internal.operators.maybe.MaybeConcatArray$ConcatMaybeObserver.drain(MaybeConcatArray.java:153) 
                                                                                                    	at io.reactivex.rxjava3.internal.operators.maybe.MaybeConcatArray$ConcatMaybeObserver.request(MaybeConcatArray.java:78) 
                                                                                                    	at io.reactivex.rxjava3.internal.operators.flowable.FlowableElementAtMaybe$ElementAtSubscriber.onSubscribe(FlowableElementAtMaybe.java:66) 
                                                                                                    	at io.reactivex.rxjava3.internal.operators.maybe.MaybeConcatArray.subscribeActual(MaybeConcatArray.java:42) 
                                                                                                    	at io.reactivex.rxjava3.core.Flowable.subscribe(Flowable.java:16013) 
                                                                                                    	at io.reactivex.rxjava3.internal.operators.flowable.FlowableElementAtMaybe.subscribeActual(FlowableElementAtMaybe.java:36) 
                                                                                                    	at io.reactivex.rxjava3.core.Maybe.subscribe(Maybe.java:5377) 
                                                                                                    	at io.reactivex.rxjava3.internal.operators.maybe.MaybeToSingle.subscribeActual(MaybeToSingle.java:46) 
                                                                                                    	at io.reactivex.rxjava3.core.Single.subscribe(Single.java:4855) 
                                                                                                    	at io.reactivex.rxjava3.internal.operators.single.SingleSubscribeOn$SubscribeOnObserver.run(SingleSubscribeOn.java:89) 
                                                                                                    	at io.reactivex.rxjava3.core.Scheduler$DisposeTask.run(Scheduler.java:644) 
                                                                                                    	at io.reactivex.rxjava3.internal.schedulers.ScheduledRunnable.run(ScheduledRunnable.java:65) 
                                                                                                    	at io.reactivex.rxjava3.internal.schedulers.ScheduledRunnable.call(ScheduledRunnable.java:56) 
                                                                                                    	at java.util.concurrent.FutureTask.run(FutureTask.java:264) 
                                                                                                    	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:307) 
                                                                                                    	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1137) 
                                                                                                    	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:637) 
                                                                                                    	at java.lang.Thread.run(Thread.java:1012) 

APK testing

The APK can be found by going to the "Checks" tab below the title. On the left pane, click on "CI", scroll down to "artifacts" and click "app" to download the zip file which contains the debug APK of this PR. You can find more info and a video demonstration on this wiki page.

Due diligence

• I read the contribution guidelines.

[AudricV]

Thank you, your changes look good to me.

Here are some improvements on the Javadocs you added which would make them better.

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

0.0% Coverage
0.0% Duplication

[Stypox]

Thank you!

I sometimes get an undeliverable Exception thrown with this APK. Not sure if this is related:

It's unrelated, it's a problem in the extractor