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app crashes when try to get text from clipboard (Android 12)

I want to get the primary text on my clipboard and would like to know how to do that in newer android versions.
This code works perfectly when I tested it in an emulator running Android Pie, but the app crashes when I use it on my Phone running android 12.1.
please help me with this.
clipboard = (ClipboardManager) getSystemService(Context.CLIPBOARD_SERVICE);
if (clipboard.hasPrimaryClip())
clipItem = clipboard.getPrimaryClip().getItemAt(0);
clipText = clipItem.getText().toString();
Details.setText(clipItem.getText().toString());
Here's the Error I got from Logcat
2022-10-01 19:23:27.595 1349-5125 ClipboardService pid-1349 E Denying clipboard access to com.jery.tachisyrpc, the application is not in focus nor is it a system service for user 0
2022-10-01 19:23:27.595 8222-8222 AndroidRuntime com.jery.tachisyrpc D Shutting down VM
2022-10-01 19:23:27.596 8222-8222 AndroidRuntime com.jery.tachisyrpc E FATAL EXCEPTION: main
Process: com.jery.tachisyrpc, PID: 8222
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.jery.tachisyrpc/com.jery.tachisyrpc.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.CharSequence android.content.ClipData$Item.getText()' on a null object reference at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:4111) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:4277) at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:103)at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2443) at android.os.Handler.dispatchMessage(Handler.java:106) at android.os.Looper.loopOnce(Looper.java:226) at android.os.Looper.loop(Looper.java:313)
at android.app.ActivityThread.main(ActivityThread.java:8751)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:571)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1135)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.CharSequence android.content.ClipData$Item.getText()' on a null object reference
at com.jery.tachisyrpc.MainActivity.onCreate(MainActivity.java:55)
at android.app.Activity.performCreate(Activity.java:8290)
at android.app.Activity.performCreate(Activity.java:8270)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1329)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:4085)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:4277) 
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:103) 
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) 
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2443) 
at android.os.Handler.dispatchMessage(Handler.java:106) 
at android.os.Looper.loopOnce(Looper.java:226) 
at android.os.Looper.loop(Looper.java:313) 
at android.app.ActivityThread.main(ActivityThread.java:8751) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:571) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1135)

Why is my intent not working when it doesn't show any syntax error? [duplicate]

This question already has answers here:
What is a NullPointerException, and how do I fix it?
(12 answers)
Closed 1 year ago.
The function called to switch activity is
public void GoToLogIn(View v){
Intent goToLogIn = new Intent(MainActivity.this,LogInActivity.class);
startActivity(goToLogIn);
finish();
}
This segment of code is showing error on logcat:
2021-08-21 12:43:33.396 9644-9644/com.example.expenditurehandlingapplication E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.expenditurehandlingapplication, PID: 9644
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.expenditurehandlingapplication/com.example.expenditurehandlingapplication.LogInActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.pm.ApplicationInfo android.content.Context.getApplicationInfo()' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2679)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6494)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.pm.ApplicationInfo android.content.Context.getApplicationInfo()' on a null object reference
at android.content.ContextWrapper.getApplicationInfo(ContextWrapper.java:152)
at android.view.ContextThemeWrapper.getTheme(ContextThemeWrapper.java:157)
at android.content.Context.obtainStyledAttributes(Context.java:655)
at androidx.appcompat.app.AppCompatDelegateImpl.createSubDecor(AppCompatDelegateImpl.java:842)
at androidx.appcompat.app.AppCompatDelegateImpl.ensureSubDecor(AppCompatDelegateImpl.java:809)
at androidx.appcompat.app.AppCompatDelegateImpl.findViewById(AppCompatDelegateImpl.java:633)
at androidx.appcompat.app.AppCompatActivity.findViewById(AppCompatActivity.java:259)
at com.example.expenditurehandlingapplication.LogInActivity.<init>(LogInActivity.java:10)
at java.lang.Class.newInstance(Native Method)
at android.app.Instrumentation.newActivity(Instrumentation.java:1174)
I have given the proper class name, but the app still stops working at this point. Can anyone please tell me what did i do wrong in this?

Are you sure that you added all activities to Manifest file?

Android app crashed when change orientation

When the orientation of app change this error is occur kindly help me
W/ActionBarDrawerToggle: DrawerToggle may not show up because NavigationIcon is not visible. You may need to call actionbar.setDisplayHomeAsUpEnabled(true);
D/AndroidRuntime: Shutting down VM
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.explore_kpk, PID: 24892
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.explore_kpk/com.example.explore_kpk.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void androidx.recyclerview.widget.RecyclerView.setLayoutManager(androidx.recyclerview.widget.RecyclerView$LayoutManager)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3256)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3352)
at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:5389)
at android.app.ActivityThread.access$1200(ActivityThread.java:223)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1803)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:158)
at android.app.ActivityThread.main(ActivityThread.java:7231)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)
***Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void androidx.recyclerview.widget.RecyclerView.setLayoutManager(androidx.recyclerview.widget.RecyclerView$LayoutManager)' on a null object reference***
***at com.example.explore_kpk.MainActivity.onCreate(MainActivity.java:121)
at android.app.Activity.performCreate(Activity.java:6877)***
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1136)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3209)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3352) 
at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:5389) 
at android.app.ActivityThread.access$1200(ActivityThread.java:223) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1803) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:158) 
at android.app.ActivityThread.main(ActivityThread.java:7231) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120) 
I/Process: Sending signal. PID: 24892 SIG: 9
This is code in which error pointing**
at com.example.explore_kpk.MainActivity.onCreate(MainActivity.java:121)
RecyclerView recyclerView=(RecyclerView)findViewById(R.id.recyler_view);
RecyclerViewAdapter recyclerViewAdapter = new RecyclerViewAdapter(this, recyclerList);
long seed = System.nanoTime();
Collections.shuffle(recyclerList, new Random(seed));
GridLayoutManager gridLayoutManager=new GridLayoutManager(this, mNoOfColumns);
recyclerView.setLayoutManager(gridLayoutManager);
recyclerView.setAdapter(recyclerViewAdapter);

Your exception is saying that you are trying to use setLayoutManager on null object reference. This means that your recylcerView is null at the moment. I don't see your whole code so I can't give you an instant solution. What I can say for you is that each time the screen orientation is changed your current activity will be destroyed and called again. So, onCreate will be called again and everything else like you just started new Activity. Sometimes issues happen here so there is few options on how to handle these events.
Retaining an object during a configuration change
What this means is for you to keep your data while screen rotation is happening. This can be done with Bundle but if you have a large set of data then it is better to use the ViewModel object. How to do this check here:
Retaining an object during a configuration change | Android Developers
ViewModel Guide
Helpful answer on SO
Handling the configuration change yourself
This other option comes with big CAUTION. Consider this as a last resort when you really need to avoid restarts because of a configuration change. What this does is preventing your activity from the restart. If you can't save your instance then I would recommend doing this but first, try to play with ViewModel and Bundles to fix this issue.
Handling the configuration change yourself | Documentation
How to do this?
<activity
android:name=".MainActivity"
android:configChanges="orientation|screenSize|screenLayout" />
add android:configChanges line to your AndroidManifest.xml inside your <activity/> tag.

'android.os.Looper.quit()' on a null object reference - Android O

First Activity of my Application starts a STICKY sevice that I'm using for creating notifications. Recently I've noticed a bug on Android O devices: when user starts an Application and then after a few seconds application was in background state the user gets this excpetion:
FATAL EXCEPTION: main
Process: com.callcatcher.callcatcher, PID: 27566
java.lang.RuntimeException: Unable to stop service callcatcher.call.com.callcatcher.NotificationService#e5b03d1: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.os.Looper.quit()' on a null object reference
at android.app.ActivityThread.handleStopService(ActivityThread.java:3563)
at android.app.ActivityThread.-wrap26(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1721)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:171)
at android.app.ActivityThread.main(ActivityThread.java:6633)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.os.Looper.quit()' on a null object reference
at android.app.IntentService.onDestroy(IntentService.java:147)
at callcatcher.call.com.callcatcher.NotificationService.onDestroy(NotificationService.java:94)
at android.app.ActivityThread.handleStopService(ActivityThread.java:3541)
at android.app.ActivityThread.-wrap26(Unknown Source:0) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1721) 
at android.os.Handler.dispatchMessage(Handler.java:106) 
at android.os.Looper.loop(Looper.java:171) 
at android.app.ActivityThread.main(ActivityThread.java:6633) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823) 

Still not sure about the reason of exception, but I just switched from IntentService to Service and now it works fine.

Android Studio - Application has stopped, but 0 code errors

My android application was running smoothly before i install some Android Studio updates, and asked me to upgrade gradle etc after the update been installed.
Later on, the Android Studio asked me to update my Android Emulator (Emulator Nexus 5X API 24 Android v7.0), since i've made all these changes, my application has been unable to open when i click run. But remember it has no codding errors when i debug etc.
The error message from Android Monitor is:
08-13 14:07:30.735 3889-3889/? E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.smartlegal.law.freeman.smartlegal, PID: 3889
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.smartlegal.law.freeman.smartlegal/com.smartlegal.law.freeman.smartlegal.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2646)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6077)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:756)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
at com.smartlegal.law.freeman.smartlegal.MainActivity.onCreate(MainActivity.java:39)
at android.app.Activity.performCreate(Activity.java:6662)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2599)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6077)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:756)
08-13 14:07:30.744 3889-3896/? W/art: Suspending all threads took: 5.874ms

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
As the error states, you're trying to set an onClickListener on a Button that does not exist (returns null). To simplify, when you're defining your Button, you call findViewById to associate the Button in Java with an XML element, but the ID that you are passing is not valid - either you're trying to call the setOnClickListener before you call setContentView, or the ID you are passing to findViewById has a typo or simply does not exist in the XML layout file.
Some more information, such as the code to your MainActivity and the layout file, would be useful to determine the exact cause of your problem.

Yes you're right, i forgot to specify the ID for the editText and Button, that is why it wasnt possible to find them ID on XML. So i've set it up and reloaded the project and it is running smoothly now. Thanks guys for the support.
"As the error states, you're trying to set an onClickListener on a Button that does not exist (returns null). To simplify, when you're defining your Button, you call findViewById to associate the Button in Java with an XML element, but the ID that you are passing is not valid. by: Timothy Langer".