Develop Reference

Activity componnent messed up when handling configuration Changes myself

I added this code in my activity
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
setContentView(R.layout.activityView);
}
And also added this line in the Manifest file
android:configChanges="orientation|keyboardHidden|screenSize"
The activity is not restarting, but the layout is not correctly loaded : not all componnent are showing and buttons click listner is never called ...
I'm using the same name file for all the layouts. but different content depending on orientation.
I even tried with different names : activityView_port/activityView_land and changed the code to:
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE) {
setContentView(R.layout.activityView_port);
} else {
setContentView(R.layout.activityView_land);
}
}
but nothing is working ...
any help would be appreciated :)

setContentView(R.layout.activityView_land);
please dont call above method on configuration change. instead you can try with use some flag for determine what layout has to be set and call reCreate() method.
If don't want to destroy the current instance, better you can try removing and adding of views with animation.

android:configChanges="orientation|screenSize" changes my layout look

I have an Adapter class and a MainActivity. The Adapter class displays the list of children names and beside the names, it displays the time they arrived to the school. Problem is when I rotate to landscape, the time values are lost.
I considered adding in my Manifest under MainActivity
android:configChanges="orientation|keyboardHidden|screenSize"
What happens is that the time values are not lost in landscape mode but the look of the layout appears same as that of portrait mode. In real, the landscape layout looks a bit different from portrait layout.
What do I do in this case in order to obtain time values and also maintain the look of the landscape layout.

There are 2 options:
use onSaveInstanceState(Bundle outState) method in your Activity or Fragment - to save your data and restore them after rotation (in onCreate(Bundle savedInstanceState) or onRestoreInstanceState(Bundle savedInstanceState))
Example:
#Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putSerializable("time_data", (Seriazable) mTimeList);
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
if (savedInstanceState != null) {
// restore value of members from saved state
mTimeList = savedInstanceState.getSerializable("time_data");
}
...
}
use android:configChanges as you already use to handle changes by yourself but inflate landscape layout after rotation
Example:
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
// Checks the orientation of the screen
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();
}
}
I prefer the first option and also this proposed in Android guide.

you can simply set screen orientation to portrait to your perticular activity so it cant be rotate. (if you want)
like this way:
<activity android:name=".MainActivity"
android:screenOrientation="portrait">
</activity>

save value of a variable in a DialogFragment when the screen rotates

Well, I wanted to save value of a variable contained in a dialogFragment when the screen is rotated in Android. I've tried every method I could find on the internet, and none of them has worked for me. Some kill my application, and others simply were not doing anything.
I need a real and effective way to save the value of an EditText that is reset when the device screen rotates. The EditText is in a DialogFragment turn this into a FragmentActivity.
thank you very much

Set your fragment's retaingInstance flag to true:
http://developer.android.com/reference/android/app/Fragment.html#setRetainInstance(boolean)
This prevents Fragment instance from being recreated.
Also be sure you don't recreate the fragment all the time:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
if (savedInstanceState == null) {
Fragment f = new Myfragment();
f.setRetainInstance(true);
getSupportFragmentManager().beginTransaction()
.add(R.id.container, f))
.commit();
}
}
Since View state is preserved during Activity recreation and your are keeping the same Fragment instance you don't need to save TextView value all the time.

I don't know if I understood your question, but you can capture the rotation as follows:
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
if (newConfig.orientation == Configuration.ORIENTATION_PORTRAIT)
{
//save value
}
if (newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE)
{
//save value
}
}
If you want that your activity don't restart, you should add this into the manifest file:
<activity
.....
android:configChanges="keyboardHidden|orientation|screenSize"
..... >
</activity>

I just found out that you can not apply the methods to save bundles automatically to the dialogues, but these would apply to activities or fragments of these dialogues dependent. If I can fix it by code, will put the solution here. thank you

Where to check for orientation change in an android fragment

In my app, I have a FragmentActivity with multiple Fragments all in portrait mode except for one specific Fragment. I move between Fragments through footer Views in the FragmentActivity.
I have a different layout (actually have the same name but different widget Views) for this specific Fragment when there is an orientation change. When in landscape mode, I want to remove specific widgets from the Fragment layout View and the footer View of the FragmentActivity and when back in portrait, add everything back.
I have saved all the data I need in onSavedInstanceState() in the Fragment, but where best should I possibly test for an orientation change so that I can restore the Views appropriately?
Not sure I can override onConfigurationChange() and test there in my Fragment because I don't have the android:configChanges="orientation" in my android Manifest.

Keep this check in onCreate(). When you rotate your device the app is restarted. So onCreate is called again when the app restarts.
int currentOrientation = getResources().getConfiguration().orientation;
if (currentOrientation == Configuration.ORIENTATION_LANDSCAPE) {
// Landscape
}
else {
// Portrait
}

You can control the orientation change by overriding onConfigurationChanged function of your fragment as well.
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
int currentOrientation = getResources().getConfiguration().orientation;
if (currentOrientation == Configuration.ORIENTATION_LANDSCAPE){
Log.v("TAG","Landscape !!!");
}
else {
Log.v("TAG","Portrait !!!");
}
}

After orientation switch, TextView is no longer updating

I have an Activity with a TextView, created in the usual findViewById method, using the definition from my xml layout file.
I'm updating the text in the TextView using a handler, created in the onCreate() method.
When I switch orientation, the TextView no longer updates from the same Handler.
If my xml definition states a value for android:text="blabla", then I see "blabla" in the view, but cannot update it anymore.
What's happening?!

When u switch orientation, android create new view.
I'd suggest making that mHandler volatile.
If u decide just to use only one orientation, for landscape add android:screenOrientation in activity tag in android manifest

The reason why you cannot update anymore is because Activity reference is different.
Your first created Activity 'A', has handler 'a'.
Now handler 'a' only can update view that belong Activity 'A'.
So when orientation happened, Activity 'A' is destroyed and Activity 'B' and handler 'b' is created.
So 'a' cannot update 'B's view in front of screen.
For quick solution I recommend you disable re-create activity when mobile orientation rotated.
AndroidManifest.xml
<activityandroid:name=".MyActivity"
android:configChanges="orientation|keyboardHidden|screenSize"
android:label="#string/app_name">
Activity
#Override
public void onConfigurationChanged(Configuration newConfig){
super.onConfigurationChanged(newConfig);
// Checks the orientation of the screen
if(newConfig.orientation ==Configuration.ORIENTATION_LANDSCAPE){
Toast.makeText(this,"landscape",Toast.LENGTH_SHORT).show();
}elseif(newConfig.orientation ==Configuration.ORIENTATION_PORTRAIT){
Toast.makeText(this,"portrait",Toast.LENGTH_SHORT).show();
}
}
now onCreate will not be called when orientation.

Try using,
#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
}
}