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Error in using a checkbox between multiple activities

I am trying to write a settings activity in an application on Eclipse. In the Main Activity, it has a button that runs a certain command. In the settings activity, I want to have a checkbox that when checked, changes what the button in the Main Activity runs when it is tapped. Right now, I have it so that when the checkbox is checked, it changes the value of a boolean and passes it to the main activity. When the button in the main activity is tapped, it checks to see if the boolean is true or false. All of this works perfectly, but when I return to the settings activity after that, the checkbox is unchecked. What should I do to have it stay checked after I go to another activity?

I believe the comment I posted is the answer:
You need to save the state of the activity. This information can be found at Saving Android Activity state using Save Instance State but in short you need to override these two methods:
#Override
public void onSaveInstanceState(Bundle savedInstanceState) {
super.onSaveInstanceState(savedInstanceState);
}
and
#Override
public void onRestoreInstanceState(Bundle savedInstanceState) {
super.onRestoreInstanceState(savedInstanceState);
}

you can use shared preference in android to store state. take look at this
http://developer.android.com/guide/topics/data/data-storage.html#pref
and
http://www.androidhive.info/2012/08/android-session-management-using-shared-preferences/

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.

Android - first app onCreate null parameter

I start develop app for Android. I have some code write in Eclipse and I use attached emulator. When I send porgram to my emulator I get some error.
Debugger show in line super.onCreate(savedInstanceState); // savedInstanceState = null
My code
public class PushAndroidActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
try
{
super.onCreate(savedInstanceState);
checkNotNull(SENDER_ID, "SENDER_ID");

Could you just try rotating your device - left ctrl F11. you will realize that the bundle is != null
onSaveInstanceState() will be called by default for a view if it has an id. The default implementation takes care of most of the UI per-instance state for you by calling onSaveInstanceState() on each view in the hierarchy that has an id. You could check these :
savedInstanceState is always null
When are ALL the cases when the onSaveInstanceState() method called?

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.

Android orientation changing exceptions

I'm having a hard time with the screen orientation in Android. I have an activity which captures a signature after the user draws his signature on the device. And for that activity I am passing a parceable object and I get it in oncreate. When the activity changes the orientation sometimes the activity cannot get the parceable object and gives an exception. I tried using a static object for the parceable object but no use. I tried onsaveinstance state method and onRetainNonConfigurationInstance methods as well.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.signature_capture_view);
Bundle bundle = getIntent().getExtras();
info = bundle.getParcelable("info");
logo= (Bitmap) bundle.get("logo");
}
And my save instance state method is like this;
#Override
protected void onSaveInstanceState(Bundle outState) {
outState.putParcelable("info", info);
super.onSaveInstanceState(outState);
}
From the onconfiguration changed method i call the setcontentview method to set a fresh layout.
#Override
public void onConfigurationChanged(Configuration newConfig) {
setContentView(R.layout.signature_capture_view);
super.onConfigurationChanged(newConfig);
}
Sometimes when the orientation changes an out of memory exception occurs from the setcontentview method.
Any help would be greatly appreciated. Thanks in advance.

Try to set the below android:configChanges attributes inside the AndroidManifest.xml file:
<activity android:name=".MyActivity"
android:label="#string/app_name"
android:configChanges="orientation|keyboardHidden">
And if you wants that your application should be fixed to open either in Portrait or in Landscape mode then add android:screenOrientation inside the activity tag:
<activity android:name=".MyActivity"
android:label="#string/app_name"
android:configChanges="orientation|keyboardHidden"
android:screenOrientation="portrait">

if you are changing the View in landscape / portrait then you should follow these steps to resolve the out of memory error.
set this in the manifest on the activity tag
android:configChanges="orientation"
in Anctivity put
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
this.recreate();
}

Try to set this in the manifest on the activity tag for the out of memory error:
android:configChanges="orientation"

I finally found the answer to my out of memory, In my signature drawing view I did not check the bitmap in the view for null and everytime the device changes the orientation it creates the bitmap inside the view. And it generates the OOM. So i inserted a null check for the bitmap and the oom disappeared. Thanks for the quick replys guys.