How to handle screen orientation change when progress dialog and background thread active

Programming

Processing sturdy Android functions requires cautious information of however they behave nether assorted circumstances, together with surface predisposition adjustments. This seemingly elemental act tin wreak havoc connected an app if not dealt with appropriately, particularly once a advancement dialog is displayed and a inheritance thread is actively moving. Ideate a person rotating their instrumentality mid-obtain – with out appropriate dealing with, the app may clang, frost, oregon suffer information. This station dives into the intricacies of managing surface predisposition modifications gracefully successful specified eventualities, guaranteeing a creaseless person education.

Knowing the Situation

Once the surface predisposition adjustments, Android destroys and recreates the act by default. This is supposed to reload the format optimized for the fresh predisposition. Nevertheless, this recreation procedure tin interrupt moving threads and disregard progressive dialogs, starring to respective possible points:

1. Thread Interruption: Inheritance threads mightiness beryllium abruptly terminated, leaving incomplete duties and possibly corrupting information.

2. Dialog Dismissal: The advancement dialog disappears, leaving the person unaware of the ongoing cognition’s position.

three. Information Failure: Accusation related with the act mightiness beryllium mislaid if not decently saved and restored.

Stopping Act Recreation

1 attack to debar these points is to forestall the act from being recreated wholly. This tin beryllium achieved by including the android:configChanges property to the act declaration successful your manifest record.

xml <act android:sanction=".MainActivity" android:configChanges=“predisposition|screenSize|keyboardHidden” > </act> This tells the scheme to grip the configuration alteration itself and not recreate the act. Your act volition past have a call to the onConfigurationChanged() technique, wherever you tin manually replace immoderate sources oregon layouts arsenic wanted.

Nevertheless, this attack is mostly little beneficial, arsenic it requires guide dealing with of format changes and tin complicate issues if you activity a broad scope of surface sizes and orientations.

Dealing with Configuration Adjustments with ViewModel

A much strong and really helpful attack is to usage the ViewModel people from the Android Structure Parts. ViewModels are designed to last configuration adjustments similar surface rotation. By storing information and logic inside a ViewModel, you tin guarantee that ongoing operations and advancement accusation are preserved throughout the recreation procedure.

Make a ViewModel people that holds references to your inheritance thread and advancement dialog government. This permits you to detach the lifecycle of these parts from the act’s lifecycle.

Implementing onSaveInstanceState() and onRestoreInstanceState()

For information that is not appropriate for a ViewModel (e.g., transient UI government), you tin leverage the onSaveInstanceState() and onRestoreInstanceState() strategies. onSaveInstanceState() permits you to prevention cardinal-worth pairs representing the act’s government earlier it’s destroyed. onRestoreInstanceState() is past known as last the act is recreated, offering you with the saved government bundle to reconstruct the act’s former government.

Champion Practices for Inheritance Threads and Dialogs

See utilizing a room similar Kotlin Coroutines oregon RxJava for managing inheritance threads. These libraries supply mechanisms for dealing with lifecycle occasions and gracefully stopping threads once the act is destroyed. Once utilizing a advancement dialog, brand certain it is dismissable and guarantee it’s decently re-displayed last the act is recreated.

  • Usage a accordant coding kind.
  • Papers your codification completely.
  1. Program your app’s structure.
  2. Instrumentality the center performance.
  3. Trial totally.

Infographic Placeholder: (Illustrating the lifecycle of an act throughout surface rotation and the function of ViewModels)

For additional speechmaking, research these assets:

Seat much connected Android improvement present.

FAQ

Q: What are the communal pitfalls once dealing with surface predisposition modifications?

A: Communal errors see not redeeming and restoring the act’s government, improper dealing with of inheritance threads, and failing to disregard oregon re-show dialogs accurately.

By knowing the lifecycle of an act and using the disposable instruments similar ViewModels, onSaveInstanceState(), and sturdy threading libraries, you tin make Android functions that grip surface predisposition adjustments seamlessly. This ensures a affirmative person education, equal throughout analyzable operations involving inheritance threads and advancement dialogs. Return the clip to instrumentality these methods, and your customers volition acknowledge the polished and resilient quality of your app. See exploring precocious ideas similar retained fragments for much specialised eventualities, oregon delve deeper into Kotlin Coroutines and RxJava for optimized inheritance project direction. A unchangeable and responsive app is cardinal to person restitution, and appropriate dealing with of surface predisposition modifications is a important measure successful reaching that end.

Question & Answer :
My programme does any web act successful a inheritance thread. Earlier beginning, it pops ahead a advancement dialog. The dialog is dismissed connected the handler. This each plant good, but once surface predisposition modifications piece the dialog is ahead (and the inheritance thread is going). Astatine this component the app both crashes, oregon deadlocks, oregon will get into a bizarre phase wherever the app does not activity astatine each till each the threads person been killed.

However tin I grip the surface predisposition alteration gracefully?

The example codification beneath matches approximately what my existent programme does:

national people MyAct extends Act implements Runnable { national ProgressDialog mProgress; // UI has a fastener that once pressed calls direct national void direct() { mProgress = ProgressDialog.entertainment(this, "Delight delay", "Delight delay", actual, actual); Thread thread = fresh Thread(this); thread.commencement(); } national void tally() { Thread.slumber(ten thousand); Communication msg = fresh Communication(); mHandler.sendMessage(msg); } backstage last Handler mHandler = fresh Handler() { @Override national void handleMessage(Communication msg) { mProgress.disregard(); } }; }

Stack:

E/WindowManager( 244): Act MyAct has leaked framework com.android.inner.argumentation.impl.PhoneWindow$DecorView@433b7150 that was primitively added present E/WindowManager( 244): android.position.WindowLeaked: Act MyAct has leaked framework com.android.inner.argumentation.impl.PhoneWindow$DecorView@433b7150 that was primitively added present E/WindowManager( 244): astatine android.position.ViewRoot.<init>(ViewRoot.java:178) E/WindowManager( 244): astatine android.position.WindowManagerImpl.addView(WindowManagerImpl.java:147) E/WindowManager( 244): astatine android.position.WindowManagerImpl.addView(WindowManagerImpl.java:ninety) E/WindowManager( 244): astatine android.position.Framework$LocalWindowManager.addView(Framework.java:393) E/WindowManager( 244): astatine android.app.Dialog.entertainment(Dialog.java:212) E/WindowManager( 244): astatine android.app.ProgressDialog.entertainment(ProgressDialog.java:103) E/WindowManager( 244): astatine android.app.ProgressDialog.entertainment(ProgressDialog.java:ninety one) E/WindowManager( 244): astatine MyAct.direct(MyAct.java:294) E/WindowManager( 244): astatine MyAct$four.onClick(MyAct.java:174) E/WindowManager( 244): astatine android.position.Position.performClick(Position.java:2129) E/WindowManager( 244): astatine android.position.Position.onTouchEvent(Position.java:3543) E/WindowManager( 244): astatine android.widget.TextView.onTouchEvent(TextView.java:4664) E/WindowManager( 244): astatine android.position.Position.dispatchTouchEvent(Position.java:3198)

I person tried to disregard the advancement dialog successful onSaveInstanceState, however that conscionable prevents an contiguous clang. The inheritance thread is inactive going, and the UI is successful partially drawn government. Demand to termination the entire app earlier it begins running once more.

Edit: Google engineers bash not urge this attack, arsenic described by Dianne Hackborn (a.ok.a. hackbod) successful this StackOverflow station. Cheque retired this weblog station for much accusation.

You person to adhd this to the act declaration successful the manifest:

android:configChanges="predisposition|screenSize"

truthful it appears to be like similar

<act android:description="@drawstring/app_name" android:configChanges="predisposition|screenSize|keyboardHidden" android:sanction=".your.bundle">

The substance is that the scheme destroys the act once a alteration successful the configuration happens. Seat ConfigurationChanges.

Truthful placing that successful the configuration record avoids the scheme to destruct your act. Alternatively it invokes the onConfigurationChanged(Configuration) technique.