Question

I have to give a dialog when my activity is launched at first time.
So I do that in my

public void onCreate(Bundle savedInstanceState)

and use

protected void onSaveInstanceState (Bundle outState) 

to save the time of my launch. I notice that OS create a new “Bundle outState” instead of using the old one. And I can not debug the the date when re Oncreate.

My question:

1. The date I saved in onSaveInstanceState , could be really read by Oncreate? And how to debug?

2. Could I just use a private member vary to save the state and without being deleted by OS when the process is killed by OS.

Thank you for your help.

Answer 1

Bundle cannot be used to carry the data across application restarts.

You’d better save your data to the more permanent storage, like SharedPreferences, put this code in onCreate():

SharedPreferences prefs;
prefs = getSharedPreferences( "preferences", Context.MODE_PRIVATE);
long last_run_time = prefs.getLong( 'last_run', 0 );
if( last_run_time == 0 ) { // zero means your app has never been run
    // display dialog, this is the first time!
    ....
    // this saves current system time to prevent your dialog being seen again
    prefs.edit().putLong( 'last_run', system.currentTimeMillis() ).commit();
}