How to call a method just before an app is closed?

Question

I have a variable who contains data that can change when user is using app. My goal is to store those data in SharedPrefs just before user is closing app, I was thinking about something like

OnStop()  {
Preferences.edit()... }

but i don't know the correct syntax ... thanks in advance guys

Answer 1

Save your data in SavedPrefs in onStop Method.

Syntex will be like

In onStop Method

@Override
protected void onStop() {
    super.onStop();
    SharedPreferences saved_values = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
    SharedPreferences.Editor editor = saved_values.edit();
    edit.putString("key", "stringToBeSaved")

    editor.commit();
}

And then to retrive your data in onCreate method

@Override
protected void onCreate(Bundle savedInstanceState) {
    SharedPreferences saved_values = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
    String foo = saved_values.getString("key", "default_string");
}

Remember the key should be same.

For more info check out Android docs on
Shared Preferences: Save key-value data
Android Lifecycle: Understand the Activity Lifecycle