Question

i have a default activity that starts first (Activity A), and from there the user can go to another activity (Activity B). In B after some work the user sets a sharedpreference. the next time the app starts i want to check in A if sharedpreference is null to go to B. and i put this if just under

 public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

and it encapsulates the whole onCreate. when the app starts it skips A and on B i shows the layout and the FC with NullPointerException.

Any one got experience with this?

OR

any one got a better idea on skipping A?

Answer 1

Well Simon you have to use Shared prefrences. save your data in shared prefrences. Then in the activity where you want to use the data in Shared prefres again get instance of same shared prefrence. get the data and use it.

go through this code

public class Calc extends Activity {
    public static final String PREFS_NAME = "MyPrefsFile";

    @Override
    protected void onCreate(Bundle state){         
       super.onCreate(state);
       . . .

       // Restore preferences
       SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
       boolean silent = settings.getBoolean("silentMode", false);
       setSilent(silent);
    }

    @Override
    protected void onStop(){
       super.onStop();

      // We need an Editor object to make preference changes.
      // All objects are from android.context.Context
      SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
      SharedPreferences.Editor editor = settings.edit();
      editor.putBoolean("silentMode", mSilentMode);

      // Commit the edits!
      editor.commit();
    }
} 

probably you will get an insight