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How to handle activity orientation change to dont recreate the activity?

I start an activity with startActivityForResult() but after the orientatikn changed and i return to the onActivityResult() method the requestCode not the same. I would like to use different layout if the screen orientation is in landscape mode.
I tried in the manifest the configuration with orientation and screenSize params, but if i use this the layout not changed to the landscape layout.
I started the activity with requestCode=0 but after the orientation changed i see that the requestCode = 66357 or something.

you can declare that your activity handles the configuration change itself, which prevents the system from restarting your activity.
In your AndriodMainfest.xml define configChanges
<activity android:name=".ResultActivity"
android:configChanges="orientation|keyboardHidden"
android:label="#string/app_name">
Then in your ResultActivity.java(that you call to get result) define onConfigurationChanged()
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
if (newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE) {
Toast.makeText(this, "landscape", Toast.LENGTH_SHORT).show();
} else if (newConfig.orientation == Configuration.ORIENTATION_PORTRAIT){
Toast.makeText(this, "portrait", Toast.LENGTH_SHORT).show();
}
}
official link

Create two types of the layout folders. "layout-land" and "layout-port". put the required xml in both the directory with same name.

You have two options:
A)Set your app to not rotate.
B)Or accept that the world is not perfect yet and modify your app to handle configuration change

android- Listener lost when screen orientation changes

I have a ListFragment which opens an Activity when it is clicked. Now, my problem is that my listener is lost when the screen is rotated. The click events does not respond. I have tried android:configChanges , it fixes the listener problem but the layout of the whole activity looks weird. Any possible solutions to set listener again on configuration change?

Best solution: The better way to handle the problem by using onSaveInstanceState().see this link Handling Runtime Changes
No.2: You can detect the change and then handle it through the below method:
public void onConfigurationChanged(Configuration config) {
super.onConfigurationChanged(config);
// Checks the orientation
if (config.orientation == Configuration.ORIENTATION_LANDSCAPE) {
Toast.makeText(this, "landscape mode", Toast.LENGTH_SHORT).show();
} else if (config.orientation == Configuration.ORIENTATION_PORTRAIT){
Toast.makeText(this, "portrait mode", Toast.LENGTH_SHORT).show();
}
}
The forced solution: if you don't want to recycle the activity lifecycle on orientation change then you can add this in your manifest:
<activity android:name=".YourActivity"
android:configChanges="orientation|keyboardHidden"
android:label="#string/app_name">
The last one is the worst solution, but works.
As my suggestion never use the last one because you can't able to do any kind of recycle things in future. but for emergency solution its good.

android application crashes when rotating the screen

My app crashec when rotating the device. I know it crashes because whenI rotate the screen it tries to create new View to draw and display but how can it create the view and display it properly on the launch but crashes when trying to create the second new view?
I dont know what part of my code I should post here? Can you give a clue to solve this problem?
I found something usefull. I put try/catch statement and now when I rotate the device, it doesnt crash but displays a blank page, when I re-rotate to the old position it display the page. here is my code
#Override
protected void onCreate(Bundle savedInstanceState) {
try{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
mViewPager = (ViewPager) findViewById(R.id.pager);
mViewPager.setAdapter(mSectionsPagerAdapter);
} catch (Exception e) {
Log.i("my_error", e.getMessage());
}
}
but eclipse cannot catch the exception.
How can I solve this problem?

There are two possible ways to do this:
1) You don't care about the orientation change of the screen and you just want to be "resized". Just add the following properties in your Manifest file:
<activity
android:name=".SplashScreen"
android:configChanges="orientation|keyboardHidden|screenSize" ... />
and add this lines of code in your activity:
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
// do nothing, just override
}
2) You do care about the orientation change. Then there are a couple of things that you should know about the activity lifecycle in an orientation change.
Firstly the onConfigurationChanged() is called and you should store in a Bundle everything that you need. For example the user has editted an EditText and you should save the value.
Why to do that? Because afterwards the onCreate() method will be called again in order for you to implement a different layout or alter something in the Views. You should then take the previously saved Bundle and restore the variables that you saved in your newly created layout.

Just add the android:configChanges="orientation" to your activity
<activity android:name=".MyActivity"
android:configChanges="orientation"/>
if you given like this, then oncreate will not called if your screen orientation is changed.
If you need more information about this you can check this link

There are a couple of things you can do:
1) Ignore screen orientation changes. If your app is only designed for portrait mode, most likely it won't look good in landscape mode and vice versa. Best is to specify the target orientation in your activities.
2) If you want to allow orientation changes, then you should have written some code re-create the view with different/modified layout. Mind sharing the code with us?

#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
//Override this and recreate your view or set adapter here
}
Dont forget to add android:configChanges="orientation" in your manifest.
On a side note you can fix orientation through manifest like this -
android:screenOrientation="portrait"

Add this to your Activity tag in the manifest:
android:configChanges="orientation|screenSize"
This will cause that the activity is not recreated on rotation change.
The flag sreenSize is for newer devices(API level 13 or higher), with including only the orientation flag the activity will stil recreate when rotating on devices running API level 13 or higher.

How to change the .xml file an activity uses?

I'm trying to handle screen-rotation myself and I need to know: How do I tell my activity to use another .xml file for the new layout? I've tried different things but none of them worked.
Best regards

You do not handle it in code, rather, you put your other layout file (with the same name) in the appropriate folder (then Android does the rest).
Like this (pseudo-code):
layout_landscape\my_layout.xml
layout\my_layout.xml
Link:
http://developer.android.com/guide/practices/screens_support.html

try setContentView(your new xml), you should override onConfigurationChanged() and act accordingly
Orientation change usually calls onCreate() again, and restarts the activity at a new configuration.
make sure you do the following:
Set the Activity's manifest to intercept orientation change events
android:configChanges="keyboardHidden|orientation"
Override onConfigurationChanged()
#Override
public void onConfigurationChanged(Configuration newConfig)
{
super.onConfigurationChanged(newConfig);
if (newConfig.orientation == android.content.res.Configuration.ORIENTATION_PORTRAIT)
{
setContentView(R.layout.layout_portrait);
}
else if (newConfig.orientation == android.content.res.Configuration.ORIENTATION_LANDSCAPE)
{
setContentView(R.layout.layout_landscape);
}
}
And read this, it's a great document about faster orientation changing.

onConfigurationChanged() is not being called on orientation change

I saw some related questions on SO, but I'm not able to resolve my issue.
I've created separate layout for PORTRAIT and LANDSCAPE mode.
I've modified the AndroidManifest.xml file for corresponding orientation change but onConfigurationChanged() is not working when I'm implementing it in activity.
Now the issue is at layout.addView(graphView, lp); in onCreate().
I've written absolute hard-coded value in GraphView class.
So it works perfectly foe PORTRAIT mode but graphView is not correctly placed when I switch to LANDSCAPE mode.
To resolve this I've created GraphViewLand class which is coded exclusively for LANDSCAPE mode. But it is not getting called from onConfigurationChanged().
Rest of the layout is coming perfectly as I've created separate main.xml file for each orientation. But since graphView is created programmatically, it is not placed properly.
Am I doing anything wrong here?
I just read this from here:
For any types of configuration changes you say that you handle there, you will receive a call to your current activity's onConfigurationChanged(Configuration) method instead of being restarted. If a configuration change involves any that you do not handle, however, the activity will still be restarted and onConfigurationChanged(Configuration) will not be called.
onCreate() method
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
init();
RelativeLayout layout = (RelativeLayout) findViewById(R.id.MainLayout);
RelativeLayout.LayoutParams lp = new RelativeLayout.LayoutParams(
RelativeLayout.LayoutParams.WRAP_CONTENT,
RelativeLayout.LayoutParams.WRAP_CONTENT);
lp.addRule(RelativeLayout.ALIGN_TOP, btnindex.getId());
GraphView graphView = new GraphView(this, values, "CurrentGraph",
horlabels, verlabels);
layout.addView(graphView, lp);
}
onConfigurationChanged() method
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
if (newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE) {
Toast.makeText(this, "landscape", Toast.LENGTH_SHORT).show();
Log.v("LAND", "SCPAE");
}
}
Any help appriciated :)

If you create two different types of view (for landscape and portrait) in xml and you have to write logic on different types of view then donot use android:configChanges in manifest.
If you have no android:configChanges in manifest and you have different sets of layout for landscape and portrait then when you change orientation your control will come to onCreate() inside that method you can write your logic.

Did you code onConfigurationChanged as an override in your Activity class?
Basic override:
// Called on rotation.
// Does not call onDestroy anymore due to android:configChanges="keyboardHidden|orientation" in manifest
#Override
public void onConfigurationChanged(Configuration newConfig) {
// TODO Auto-generated method stub
super.onConfigurationChanged(newConfig);
}
My manifest declaration for info:
<activity android:name=".Slime"
android:label="#string/app_name"
android:configChanges="keyboardHidden|orientation"
android:screenOrientation="landscape">

How do you say that the onConfigurationChanged() method is not called? Is the log not being printed? Isn't the toast being shown?
Secondly, you mention that the issue is at layout.addView in onCreate(). Do note that if android:configChanges is present in your manifest, then onCreate() is not called on orientation change. You need to move the piece of code that programmatically modifies the UI layout into the onConfigurationChanged() method.