How to store time in sharedpreferences across two activities

Question

When my users play a game, I want to lock them out of it for 30 seconds. I'm trying to use SharedPreferences. I'm not well acquainted with SP and not completely sure how to use it. So it should look like so

ifGameOver(){

//lock the game for 30 seconds 
//send users to main menu until 30seconds is over

}

and then at the main menu I wish to be able to see a TextView count down as the 30 seconds go down. So here I would getLong or something(?). Could anyone shed any light on this?

Answer 1

Save current time to SharedPreferences in first Activity class:

private void saveCurrentTIme() {
        SharedPreferences sharedpreferences = getSharedPreferences("myAppPref",
            Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedpreferences.edit();
        editor.putLong("GameTime", System.currentTimeMillis());
        editor.commit();
}

Retrieve saved time from SharedPreferences in second Activity class:

    private long getSavedTime() {
            SharedPreferences sharedpreferences = getSharedPreferences("myAppPref", Context.MODE_PRIVATE);
            return sharedpreferences.getLong(Name, 0L);

     }

For comparing if the saved time is passed, you can create something like Timer.

You can check this answer for how to do it.