My Goal:
So I need help putting a boolean primitives into a bundle and retrieving it from the bundle when there is a screen orientation change in Android. I am using that boolean value in a conditional statement that helps decide if 2 Button views (mTrueButton, mFalseButton) should be enabled or not. What i have so far is causing the app to shut down (aka crash) when there is a screen rotation. I think I am not retrieving or writing my boolean from my bundle or into my bundle correctly, and it is causing the app to crash.
How The App Should Works:
When a user touches the mTrueButton or mFalseButton button to answer a question, both buttons become disabled so the user is not allowed to answer again. I want those buttons to keep being disabled when the user answers and then rotates the screen.**
I know that when a user rotates their Android device, onDestroy() is called because runtime configuration changes take place, causing the app to be relaunched without having knowledge of it's previous state, (unless store my necessary data onto a bundle and pass it onto my onCreate method).
These are SOME global variables in my activity class
private int index = 0;
priavate Button mTrueButton,mFalseButton;
private static final String KEY_INDEX = "index";
private static final String BTTN_ENABLED = "bttnEnabled";
private boolean trueFalseButtonsEnabled = true;
These are SOME statements in my onCreate() method of the same activity class
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.d(TAG, "onCreate(Bundle) called");
setContentView(R.layout.activity_quiz);
if(savedInstanceState != null) {
index = savedInstanceState.getInt(KEY_INDEX, 0);
changeButtonEnableStatus(savedInstanceState.getBoolean(BTTN_ENABLED,true));
}
mTrueButton = (Button)findViewById(R.id.true_button);
mFalseButton = (Button)findViewById(R.id.false_button);
mTrueButton.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v){
checkAnswer(true);
changeButtonEnableStatus(false);
}
});
mFalseButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
checkAnswer(false);
changeButtonEnableStatus(false);
}
});
}
These are SOME methods in the same activity class but not in my onCreate()
private void changeButtonEnableStatus(boolean bool){
trueFalseButtonsEnabled = bool;
mTrueButton.setEnabled(bool);
mFalseButton.setEnabled(bool);
}
#Override
public void onSaveInstanceState(Bundle savedInstanceState){
super.onSaveInstanceState(savedInstanceState);
Log.d(TAG,"onSavedInstanceState() called");
savedInstanceState.putInt(KEY_INDEX,index);
savedInstanceState.putBoolean(BTTN_ENABLED, trueFalseButtonsEnabled);
}
Note that:
index = savedInstanceState.getInt(KEY_INDEX, 0);
works properly. It is setting global variable "index" to equal to the int primitive what was stored in into keywork "KEY_INDEX".
However I don't think: changeButtonEnableStatus(savedInstanceState.getBoolean(BTTN_ENABLED,true)); is working properly. My app seems to crash when I include that statement and run the app, and then rotate the device.
Basically what the title says. Currently if the orientation changes in my app the ball resets back to the top of the game, however I wish to change my code so that if the user changes orientation of the device the ball and racket stay in the same spot. How would I achieve this? Would I place my entire in these two methods?
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
Log.v(TAG, "onSaveInstanceState");
}
and
protected void onRestoreInstanceState(Bundle savedInstanceState) {
super.onRestoreInstanceState(savedInstanceState);
Log.v(TAG, "onRestoreInstanceState");
}
(note I have already initialized the constants for TAG, within my code not seen here).
(it's also an activity)
You could the save the position of the ball and racket in the outstate so in the activity:
#Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
//If it is an integer
outState.putInt(TAG, mBallPosition);
//Or use a serializable if you wish to store an actual object
outState.putSerializable(TAG, mBallPosition);
}
Then in your onCreate method you can restore the states :
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (savedInstanceState != null) {
int position = savedInstanceState.getInt(TAG,0);
//set ball position
//or get the object back using outstate.getSerializable(TAG)
}
}
I am new to android programming. So, I am trying to download a file from internet in async task and showing progress dialog until download finished. But if i switch my applications in between, say I open another app, progress dialog disappears.
This is the code I am using to show progress dialog
progressDialog.setIndeterminate(false);
progressDialog.setCancelable(false);
progressDialog.setMessage("Backing Up...");
progressDialog.setMax(100);
progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
progressDialog.show();
What am i doing wrong here?
First If you are using the asynctask it runs on UI Thread so you must be switching from the home button it puts your app on the pause you can override onPause and onResume methods
I solved it by adding these methods in my code.
#Override
public void onDestroyView()
{
if (progressDialog != null && getRetainInstance())
progressDialog.setDismissMessage(null);
super.onDestroyView();
}
#Override
public void onSaveInstanceState(Bundle outState) {
// TODO Auto-generated method stub
super.onSaveInstanceState(outState);
}
#Override
public void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setRetainInstance(true);
}
With SharedPreferences, i would like to save a value (that will be later the date of last update) and load it. It works well until i shut down my phone or force close my application. It resets the value.
Here's the code :
public class feedPlayer extends Activity
{
public final static String PARAM_USERDETAILS="userdetails";
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
loadvars();
savevars();
}
public void savevars()
{
SharedPreferences parametres = this.getSharedPreferences(PARAM_USERDETAILS, MODE_PRIVATE);
Editor edit = parametres.edit();
edit.clear();
//Global.Maj = "maj"
TextView maj=(TextView) findViewById(R.id.datemaj);
edit.putString("gimli", Global.MAJ);
edit.commit();
maj.setText(Global.MAJ);
}
public void loadvars()
{
SharedPreferences parametres = this.getSharedPreferences(PARAM_USERDETAILS, MODE_PRIVATE);
TextView maj=(TextView) findViewById(R.id.datemaj);
String Smaj = parametres.getString("gimli", Global.MAJ);
maj.setText(Smaj);
}
}
Use onCreate() method to load your data and onDestroy() method to save data:
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
loadvars();
}
#Override
protected void onDestroy() {
super.onDestroy();
savevars();
}
You can use too: onResume() with onPause() method but this two method are reserved for process (start process in onResume() method, stop process in onPause() method)
You are calling the savevars() method each time your activity is created. That means for sure every time your application starts.
In this method you are writing always the same value in the preferences:
edit.putString("gimli", Global.MAJ);
edit.commit();
Basically, this is what I'm doing
1) Set AlarmManager to execute BroadcastReceiver (BCR)
Intent intent = new Intent(m_Context, BCR.class);
intent.putExtras(extras);
PendingIntent pendingIntent = PendingIntent.getBroadcast(m_Context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
AlarmManager am = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
am.set(AlarmManager.RTC_WAKEUP, StartTime, pendingIntent)
2) Start MyActivity from BCR
#Override
public void onReceive(Context context, Intent intent) {
Intent newIntent = new Intent(context, MyActivity.class);
newIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_SINGLE_TOP);
context.startActivity(newIntent);
}
3) Have MyActivity turn on the screen if its not on
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().addFlags(LayoutParams.FLAG_DISMISS_KEYGUARD);
getWindow().addFlags(LayoutParams.FLAG_SHOW_WHEN_LOCKED);
getWindow().addFlags(LayoutParams.FLAG_TURN_SCREEN_ON);
setContentView(R.layout.myactivity);
}
#Overide
protected void onNewIntent(Intent intent) {
super.onNewIntent(intent);
}
For some reason, I notice that right when MyActivity is opened, it's flow goes like:
onCreate/onNewIntent -> onResume -> onPause -> onResume
I'm not sure why it does an onPause right away. I notice this only happens when the screened is being turned on by the flags. Does anyone know why this happens? Is there any way this behavior can be prevented?
if you trying request permissions every time it can cause such problems, just check if you already granted them
requestPermissions can cause it:
onCreate
onStart
onResume
onPause
onResume
Use this method ContextCompat.checkSelfPermission(context, permission) to check if permission was granted or not before requesting it
This method returns int and you can check it with PackageManager.PERMISSION_GRANTED constant
Just in case anyone else runs into this, I seem to notice this behaviour only when I inflate fragments inside of an activity via XML layout. I don't know if this behaviour also happens with the compatibility library version of Fragments (I'm using android.app.Fragment)
It seems the activity will call Activity#onResume once before calling Fragment#onResume to any added Fragments, and then will call Activity#onResume again.
Activity:onCreate
Fragment:onAttach
Activity:onAttachFragments
Fragment:onCreate
Activity: onStart
Activity: onResume
Fragment: onResume
Activity: onResume
If you have ES File Explorer then FORCE STOP it. Somehow, they interrupt your app's lifecycle (comments suggest some kind of overlay).
My issue with onResume being caused twice was because onPause was somehow being called after the activity was created.. something was interrupting my app.
And this only happens after being opened for the first time after installation or built from studio.
I got the clue from another post and found out it was because of ES File Explorer. Why does onResume() seem to be called twice?
As soon as I force stop ES File Explorer, this hiccup behavior no longer happens... it's frustrating to know after trying many other proposed solutions. So beware of any other interrupting apps like this one.
I was researching about this for a while because on the internet there is no any mention about this weird behaviour. I don't have a solution how to overcome this dark-side-behavior but I have found an exact scenario when it certainly happens.
onPause-onResume-onPause-onResume just happens every time, when app is starting first time after installation. You can simply invoke this behavior by doing any change in code and rerunning (which includes recompiling) the app from your IDE.
No matter if you use AppCompat libs or not. I have tested both cases and behavior carries on.
Note: Tested on Android Marshmallow.
I have borrowed the code from this thread about fragment and activity lifecycle and here it is (just copy, paste, declare activity in manifest and run Forest run):
import android.app.Activity;
import android.app.Fragment;
import android.app.FragmentTransaction;
import android.content.Context;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
public class TestActivity extends Activity {
private static final String TAG = "ACTIVITY";
public TestActivity() {
super();
Log.d(TAG, this + ": this()");
}
protected void finalize() throws Throwable {
super.finalize();
Log.d(TAG, this + ": finalize()");
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.d(TAG, this + ": onCreate()");
TextView tv = new TextView(this);
tv.setText("Hello world");
setContentView(tv);
if (getFragmentManager().findFragmentByTag("test_fragment") == null) {
Log.d(TAG, this + ": Existing fragment not found.");
FragmentTransaction ft = getFragmentManager().beginTransaction();
ft.add(new TestFragment(), "test_fragment").commit();
} else {
Log.d(TAG, this + ": Existing fragment found.");
}
}
#Override
public void onStart() {
super.onStart();
Log.d(TAG, this + ": onStart()");
}
#Override
public void onResume() {
super.onResume();
Log.d(TAG, this + ": onResume()");
}
#Override
public void onPause() {
super.onPause();
Log.d(TAG, this + ": onPause()");
}
#Override
public void onStop() {
super.onStop();
Log.d(TAG, this + ": onStop()");
}
#Override
public void onDestroy() {
super.onDestroy();
Log.d(TAG, this + ": onDestroy()");
}
public static class TestFragment extends Fragment {
private static final String TAG = "FRAGMENT";
public TestFragment() {
super();
Log.d(TAG, this + ": this() " + this);
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.d(TAG, this + ": onCreate()");
}
#Override
public void onAttach(final Context context) {
super.onAttach(context);
Log.d(TAG, this + ": onAttach(" + context + ")");
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
Log.d(TAG, this + ": onActivityCreated()");
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
Log.d(TAG, this + ": onCreateView()");
return null;
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
Log.d(TAG, this + ": onViewCreated()");
}
#Override
public void onDestroyView() {
super.onDestroyView();
Log.d(TAG, this + ": onDestroyView()");
}
#Override
public void onDetach() {
super.onDetach();
Log.d(TAG, this + ": onDetach()");
}
#Override
public void onStart() {
super.onStart();
Log.d(TAG, this + ": onStart()");
}
#Override
public void onResume() {
super.onResume();
Log.d(TAG, this + ": onResume()");
}
#Override
public void onPause() {
super.onPause();
Log.d(TAG, this + ": onPause()");
}
#Override
public void onStop() {
super.onStop();
Log.d(TAG, this + ": onStop()");
}
#Override
public void onDestroy() {
super.onDestroy();
Log.d(TAG, this + ": onDestroy()");
}
}
}
I don't know for sure what's going on, but I suspect that your activity is being restarted because setting the screen on is treated by the system as a configuration change. You might try logging the configuration on each call to onResume to see if that's what's happening and, if so, what is actually changing. You can then modify the manifest to tell the system that your activity will handle the change on its own.
protected void onResume() [
super.onResume();
Configuration config = new Configuration();
config.setToDefaults();
Log.d("Config", config.toString());
. . .
}
I have similar problem.
My situation was next
CurrentActivity extends MainActivity
CurrentFragment extends MainFragment
I was opening CurrentActivity with intent as usually. In onCreate CurrentAcitivity I was replacing CurrentFragment.
Life Cycle was:
1. onResume MainActivity
2. onResume CurrentActivity
3. onResume MainFragment
4. onResume CurrentFragment
called onPause Automatically, and after that again
onResume MainActivity
onResume CurrentActivity
onResume MainFragment
onResume CurrentFragment
I decide to retest everything and after few hours spend trying and playing I found root issue.
In MainFragment onStart I was calling startActivityForResult every time (in my case android popup for turning on Wifi) which was call onPause on MainFragment. And all of us know that after onPause next is onResume.
So its not Android bug, it's only mine :-)
Happy lifecycle debuging!
I also ran into this onresume-onpause-onresume sequence (on 4.1.2 and above, but I did not experience this on 2.3). My problem was related to wakelock handling: I accidentally forgot to release a wakelock and reacquiring it caused an error with a message "WakeLock finalized while still held". This problem resulted in onPause being called immediately after onResume and resulted in faulty behavior.
My suggestion is: check for errors in the log, those might be related to this issue.
Another hint: turning on the screen might be a bit more tricky than simply using window flags. You might want to check this answer here - it suggests you set up a receiver to check if the screen has already been turned on and launch the desired activity only after: https://stackoverflow.com/a/16346369/875442
I had a similar issue, and my problem was that at the onCreate() method, I was doing:
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
super.setContentView(R.layout.friends); <-- problem
}
My call to "super." was triggering the onResume() twice. It worked as intended after I changed it to just:
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.friends); <-- 'super.' removed
}
Hope it helps.
Have you tried calling your getWindow().addFlags(...) before calling super.onCreate(savedInstanceState) in onCreate method?
I had a similar problem. onResume was called twice when my onCreate looked like this:
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_YES);
setContentView(R.layout.main);
...
}
Changing it to:
#Override
public void onCreate(Bundle savedInstanceState) {
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_YES);
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
...
}
... fixed the problem.
It seems that using Activity from the support library saves and restores instance automatically. Therefore, only do your work if savedInstanceState is null.
I just ran into this, and it seems that getWindow().addFlags() and tweaking Window properties in general might be a culprit.
When my code is like this
#Override
protected void onCreate(Bundle savedInstanceState) {
requestWindowFeature(Window.FEATURE_NO_TITLE);
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_generic_fragment_host);
// performing fragment transaction when instance state is null...
onResume() is triggered twice, but when I remove requestWindowFeature(), it's only called once.
I think you should have a look at that question:
Nexus 5 going to sleep mode makes activity life cycle buggy
You should find leads
Basically a lot of stuff can trigger this. Some resume processes that loses focus can do it. A few apps will cause it to happen too. The only way to cope is to block the double running. Note, this will also have an errant pause thrown in for good measure.
boolean resumeblock = false;
#Override
protected void onResume() {
super.onResume();
sceneView.getViewTreeObserver().addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
#Override
public boolean onPreDraw() {
sceneView.getViewTreeObserver().removeOnPreDrawListener(this);
if (resumeblock) return false;
resumeblock = true;
//Some code.
return false;
}
});
}
This is a solid way to prevent such things. It will block double resumes. But, it will also block two resumes that preserve the memory. So if you just lost focus and it doesn't need to rebuild your stuff. It will block that too. Which might be a benefit clearly, since if you're using the resume to control some changes over focus, you only actually care if you need to rebuild that stuff because of focus. Since the pre-draw listeners can only be called by the one thread and they must be called in sequence, the code here will only run once. Until something properly destroys the entire activity and sets resumeblock back to false.
as #TWL said
ES File Explorer
was the issue for me !
Uninstalling the app solved the problem.
When this ES File Explorer was installed, onStart() -> onResume() -> onPause() -> onResume() .. was the problem.
onResume() was called 2'ce.
I had the same problem. Mine was for this code in runtime
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
I just put it in manifest
android:screenOrientation="landscape"
no more problem about twice call to onCreate and onResume.
I didn't see an adequate answer to the question, so I decided this.
From My Notes:
"It seems that the activity runs onResume() onPause() then onResume again. The very last method that runs is the onSizeChanged(). So a good practice would be to start threads only after the onSizeChanged() method has been executed."
So you could: Make a log of each method that runs. Determine the last method that runs. Ensure that you have a Boolean that initializes false, and only changes to true after your last method runs. Then you can start all threading operations, once you check that the Boolean is true.
-For anyone wondering: I am using a surfaceview that has a onSizeChanged() method that executes very last.
I had the same problem because of setting the UiMode in the onCreate() of MainActivity. Changing the theme triggered activity recreation and made two calls to onPause() and onStart().
I was sure this was happening in my app until I realized I had planted two of Jake Wharton's Timber trees, and onResume() was just being logged twice, not called twice.
i also faced this issue this is because of fragments..
the number of fragments you have in activity onResume() will call that number of times. to overcome i used flag variables in SharedPrefrences