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Method called BEFORE orientation change

After the orientation changes, this method is called:
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
}
But how do I take action BEFORE the guidance change? I need it before it changes, I save some things in SQLite.
Is there any way to do this?

Your activity calls that onCreate() with different execution params in every orientation changes. But you can handle those changes by configuring configChanges tag in the manifest file.
For example, the following manifest code declares an activity that handles both the screen orientation change and keyboard availability change:
<activity android:name=".MyActivity"
android:configChanges="orientation|keyboardHidden"
android:label="#string/app_name">
you can find all the details about this configChanges by navigating this https://developer.android.com/guide/topics/resources/runtime-changes android official documentation.
You can use this knowledge and do what you want when triggering this method while orientation changes.

Android App orientation change restarts activity

I have an activity and it is getting restarted whenever orientation changes. I have written code to prevent activity restart upon change in orientation in the manifest file as given below:
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.sample.appname.MainActivity"
android:label="#string/app_name"
android:configChanges="orientation|keyboardHidden"
>
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
In the above code snippet android:configChanges="orientation|keyboardHidden" is supposed to do the work for me but the activity is still getting restarted. Please let me know how to correct it.

Actually you shouldn't prevent the Activity to be restarted. It is neccessary to recreate the Activity after a rotation change for several reasons. One of it is that the layout has to be inflated to deal with the changed screen size and things like that (it's easy to imagine that the layout is totally different in portrait than it is in landscape mode).
However, there is a way you can tell the system that you deal with the screen changes by yourself. Therefore change the line in your manifest
android:configChanges="orientation|keyboardHidden"
to
android:configChanges="orientation|screenSize"
The activity won't be recreated then. You'll get a callback via the onConfigurationChanged() method so you can do something when the orientation has changed. If you don't want to do anything when the configuration has changed, just don't override the onConfigurationMethod() in your Activity. Read this section in the Android Developers API Guide for more information.
I got this from this answer. There are two more approaches in the answer but I think the one I described above is the best in your case.
EDIT: Maybe you have to add keyboard|keyboardHidden to the android:configChanges attribute as well, as stated in this answer
EDIT #2: If you want to retrieve the current orientation of the device you can call
Activity.getResources().getConfiguration().orientation
which will return the constants ORIENTATION_PORTRAIT or ORIENTATION_LANDSCAPE.
If you're interested in the exact rotation angle, use
int rotation = getWindowManager().getDefaultDisplay().getRotation();
and implement a differentiation with something like a switch case described here.
And a third way to determine the device's rotation is getRequestedOrientation() which will return a constant defined in the documentation

android:configChanges="orientation|screenSize" means whenever screen orientation will be changed a following method in Activity class will be called.
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
if(newConfig.orientation == Configuration.ORIENTATION_PORTRAIT) { body }
}
This is nature of andorid that whenever screen orientation is changed whole lifecycle of activity runs again.
To save and restore some data. you can use following methods.
#Override
public void onSaveInstanceState(Bundle outState, PersistableBundle outPersistentState) {
super.onSaveInstanceState(outState, outPersistentState);
outState.putString("key","value");
}
#Override
protected void onRestoreInstanceState(Bundle savedInstanceState) {
super.onRestoreInstanceState(savedInstanceState);
String s = savedInstanceState.getString("key");
}

Try changing
android:configChanges="orientation|keyboardHidden"
Into
android:configChanges="orientation|screenSize"
this should solve your problem, but it is not a efficient way, for a better option refer http://developer.android.com/training/basics/activity-lifecycle/recreating.html

Prevent Activity restart on rotation

I have an app that uses the below sdk in the manifest:
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
To prevent the activity from restarting on screen rotation I add to manifest :
android:configChanges="orientation|keyboardHidden|screenSize"
Do I need to override the onConfigurationChanged in activity itself also, as below:
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
setContentView(R.layout.myLayout);
}
or is this line in the manifest is enough:
android:configChanges="orientation|keyboardHidden|screenSize"
Any help will be appreciated.

To prevent the activity from restarting on screen rotation
That is usually not a very good idea.
I add to manifest : android:configChanges="orientation|keyboardHidden|screenSize"
That is usually even less of a good idea. All you do is create more work for yourself. You still have to have all of the standard configuration change logic, to handle all of the configuration changes that you do not have listed there, plus you may need to deal with these three cases separately.
Do I need to override the onConfigurationChanged
That depends upon whether your UI is different based upon configuration, for the configurations you have listed in android:configChanges (e.g., does portrait look different than landscape?). If the answer is "yes", then onConfigurationChanged() is where you will fix up that UI for the events listed in your android:configChanges roster. If the answer is "no", then you do not need to override this method.

The manifest piece below that you had is enough to prevent the rotation:
android:configChanges="orientation|keyboardHidden|screenSize"

Set
android:screenOrientation="portrait"
as suggested by Android - disable landscape mode?

Activity lifecycle - onCreate called on every re-orientation

I have a simple activity that loads a bitmap in onCreate. I find that if I rotate the device I can see from the logs that onCreate called again. In fact, because all instance variables are set to default values again I know that the entire Activity has been re-instantiated.
After rotating 2 times I get an FC because not enough memory can be allocated for the bitmap. (Are all instances of the activty still alive somewhere? Or does the GC not clean up fast enough?)
#Override
public void onCreate(Bundle savedInstanceState) {
File externalStorageDir = Environment.getExternalStorageDirectory();
File picturesDir = new File(externalStorageDir, "DCIM/Camera");
File[] files = picturesDir.listFiles(new FilenameFilter(){
public boolean accept(File dir, String name) {
return name.toLowerCase().endsWith(".jpg");
}});
if (files.length > 0) {
Bitmap bm = BitmapFactory.decodeStream(new FileInputStream(files[0]));
ImageView view = (ImageView) findViewById(R.id.photo);
view.setImageBitmap(bm);
}
}
From all that I read, onCreate should be called once during the lifetime of an application. Am I wrong about this? How can re-orienting the device cause the activity to be recreated?

android:configChanges="keyboardHidden|orientation|screenSize"
Caution: Beginning with Android 3.2 (API level 13), the "screen size"
also changes when the device switches between portrait and landscape
orientation. Thus, if you want to prevent runtime restarts due to
orientation change when developing for API level 13 or higher (as
declared by the minSdkVersion and targetSdkVersion attributes), you
must include the "screenSize" value in addition to the "orientation"
value. That is, you must decalare
android:configChanges="orientation|screenSize". However, if your
application targets API level 12 or lower, then your activity always
handles this configuration change itself (this configuration change
does not restart your activity, even when running on an Android 3.2 or
higher device).
From docs: http://developer.android.com/guide/topics/resources/runtime-changes.html

What happen when orientation changed
Life Cycle of orientation
onPause();
onSaveInstanceState();
onStop();
onDestroy();
onCreate();
onStart();
onResume();
---- app recreated and now is running ---
If you do long operation in onCreate() and want prevent re-create your activity add configChanges attribute in your mainfest
<activity android:name=".MyActivity"
android:configChanges="orientation|keyboardHidden|screenSize"
android:label="#string/app_name">
screenSize if you targeting api >= 13

Activity is recreated after each rotation by default. You can override this behaviour with configChanges attribute of the activity tag in AndroidManifest. For further details and different options, see http://developer.android.com/guide/topics/resources/runtime-changes.html

Actvity Lifecycle when you rotate screen
onPause
onSaveInstanceState
onStop
onDestroy
onCreate
onStart
onRestoreInstanceState
onResume

If you want to prevent FC from not enough memory, you need to deallocate resources in onStop() or onPause(). this allows you to use fresh memory in onCreate().
This is an alternate solution to preventing the recreation of the activity by using
android:configChanges="keyboardHidden|orientation"
As sometimes your activity's layout is different in portrait and landscape (layout, layout-land).
preventing recreate on orientation change will prevent your activity from using the other orientation's layout.

Yes, activity's onCreate() is called everytime when the orientation changes but you can avoid the re-creation of Activity by adding configChanges attribute of Activity in your AndroidManifest file in the activity tag.
android:configChanges="keyboardHidden|orientation"

On Create method will call everytime when you do orientation, to avoid this you have to use
//Define Below in you Manifest file.
<activity
android:name="com.ecordia.activities.evidence.MediaAttachmentView"
android:configChanges="keyboardHidden|orientation|screenSize"
</activity>
//Define Below in your activity.
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
if (newConfig.orientation == Configuration.ORIENTATION_PORTRAIT) {
//your code
} else if (newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE) {
//your code
}
}
It will works like a charm!!

Manifest XML activity Tag:
android:configChanges="keyboardHidden|orientation"‍‍‍
#Override
public void onConfigurationChanged(Configuration newConfig) {
// TODO Auto-generated method stub
super.onConfigurationChanged(newConfig);
}
Use the above code to perform changes related to orientation in your Activity Java Code
Cheers!!!

One of the most common and suggested “solutions” to dealing with orientation changes is to not deal with them. You can do this by setting the android:configChanges flag on your Activity in AndroidManifest.xml as shown below:
<activity
android:name=".MyActivity"
android:label="#string/title_my_activity"
android:configChanges="orientation|screenSize|keyboardHidden" />
This is NOT the correct way to deal with orientation changes.
CORRECT way is to implement the onSaveInstanceState method (this could be in your Activity, Fragment or both) and place the values you need to save in the Bundle argument that gets passed to the method.
It is nicely described here: http://code.hootsuite.com/orientation-changes-on-android/
While it may seem a bit tedious to implement, handling orientation changes properly provides you with several benefits: you will be able to easily use alternate layouts in portrait and landscape orientations, and you will be able to handle many exceptional states such as low memory situations and interruptions from incoming phone calls without any extra code.

While the Manifest way may work, there is a better and proper solution for these types of problems. The ViewModel class. You should have a look here: https://developer.android.com/topic/libraries/architecture/viewmodel
Basically, you extend the ViewModel class and define all the data members in it which we want to be unchanged over re creation of the activity (in this case orientation change). And provide relevant methods to access those from the Activity class. So when the Activity is re created, the ViewModel object is still there, and so are our data!

Kindly see my way of doing it:-
http://animeshrivastava.blogspot.in/2017/08/activity-lifecycle-oncreate-beating_3.html
snippet is:-
#Override
protected void onSaveInstanceState(Bundle b) {
super.onSaveInstanceState(b);
String str="Screen Change="+String.valueOf(screenChange)+"....";
Toast.makeText(ctx,str+"You are changing orientation...",Toast.LENGTH_SHORT).show();
screenChange=true;
}
#Override
public void onCreate(Bundle b) {
super.onCreate(b);
ctx=getApplicationContext();
if(!screenChange) {
String str="Screen Change="+String.valueOf(screenChange);
// ...
}
}

I had the same problem, in which my onCreate is called multiple times when the screen orientation is changed. My problem got solved when i add android:configChanges="orientation|keyboardHidden|screenSize" in the activity tag in manifest

I had the same problem and I did some workaround
Define didLoad boolean variable with false value
private boolean didLoad = false;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity);
if (!this.didLoad){
// Your code...
this.didLoad = true;
}

How can I keep the MediaRecorder keeps recording after an orientation change

Can you please tell me how can I keep the MediaRecorder keeps recording after an orientation change? I try looking into source code of packages/apps/SoundRecorder/src/com/android/soundrecorder/Recorder.java, I don't see it handles that cases.
Thank you.

This might be because by default the system destroys and recreates the Activity when the orientation changes. You can tell the system that your app handles changes like these by modifying the activity's tag in the manifast like this:
<activity android:name=".UIActivity"
android:configChanges="orientation|keyboardHidden"
android:label="#string/app_name"> ...
</activity>
This way you can react to these changes overriding this method:
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
//---code to redraw your activity here---
//...
}
Here, you can redraw your views to support landscape mode, or do simply nothing.