Question

If i set a sharedpreference in one activity, why does the other one has different preferences? context changed? (but i se use application context!)

Here is my code

MyApp appState = ((MyApp)this.activity.getApplicationContext());
appState.setDittaSelezionata( (int) itemId);

….

MyApp appState = ((MyApp)this.getApplicationContext());
int ditta_id_selezionata = appState.getIdSomething();

And

public class MyApp extends Application implements Parcelable {

    private SharedPreferences getSharedPrefs()
    {
    SharedPreferences settings = PreferenceManager.getDefaultSharedPreferences(this);
    //SharedPreferences settings = this.getSharedPreferences(MyApp.PREFS_NAME, this.MODE_PRIVATE);
    return settings;
}
public int getIdSomething() {
    SharedPreferences settings = this.getSharedPrefs();
    return settings.getInt("ditta_id_selezionata", 0);
}

public void setDittaSelezionata(final int ditta_selezionata) {

    SharedPreferences settings = this.getSharedPrefs();
    SharedPreferences.Editor editor = settings.edit();
    editor.putInt("ditta_id_selezionata",  ditta_selezionata);

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

…

How can i make global preferences that are shared among all activities android 3.2? is there something android provides or i have to code a save to file/open to file and add it for each activity onStop() / onCreate() ?

Answer 1

try this.

private static final String APP_PREF = "application_preference";  
private static final String DITTA = "ditta_id_selezionata";
public class MyApp extends Application implements Parcelable {

    private SharedPreferences getSharedPrefs(){
    SharedPreferences settings = getApplicationConext().getSharedPreferences(APP_PREF, Context.MODE_PRIVATE);

    return settings;
}

public int getIdSomething() {
    SharedPreferences settings = this.getSharedPrefs();
    return settings.getInt(DITTA, 0);
}

public void setDittaSelezionata(final int ditta_selezionata) {

    SharedPreferences settings = this.getSharedPrefs();
    SharedPreferences.Editor editor = settings.edit();
    editor.putInt(DITTA,  ditta_selezionata);

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

I think you had done something similar but commented it. This should keep your preferences constant throughout the app over the activities. As you see here, you make sure that the same preference file is being read and written to.