SavedInstanceState为null

Question

I want to get the current system time when I "sync" with another device. So this activity is usually called/displayed right after syncing.

Currently, the current system time is right but I also have alarm pop up another activity and once I'm finished with that activity, I want to go back to this activity. Once I do, the system time is updated to most current time and not the old current time (which is what I want).

I tried to use SavedInstanceState to save the state of the old current time and while it does get the right string in the onSavedInstanceState . When I go back to this activity, the SavedInstanceState is null. I don't know why?

public class InfoActivity extends BaseActivity  {

String fileLastSync = null;

   @Override
   public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.info);
        Resources resources = context.getResources();

        if (savedInstanceState != null) {
           // Restore value of members from saved state
           fileLastSync = savedInstanceState.getString("FileLastSync");
       } else {
           //Gets the current DateTime
           long nextTime = (System.currentTimeMillis());
           Date date = new Date(nextTime);

           //Formats the current DateTime
           SimpleDateFormat format = new SimpleDateFormat("MM-dd-yyyy HH:mm a");
           String formatDate = format.format(date);

           //Last sync time is the current formatted date
           fileLastSync = formatDate;
       }

       //Gets the 'last synced' string and sets to datetime of the last sync
       String syncString = String.format(resources.getString(R.string.last_sync), fileLastSync);

       //Dynamically sets the datetime of the last sync string
       TextView lastSyncTextView = ((TextView) findViewById(R.id.last_sync) );
       lastSyncTextView.setText(syncString);
}

    @Override
    protected void onSaveInstanceState(Bundle savedInstanceState) {

        savedInstanceState.putString("FileLastSync",fileLastSync);
        super.onSaveInstanceState(savedInstanceState);
    }

 @Override
 protected void onRestoreInstanceState(Bundle savedInstanceState) {
    super.onRestoreInstanceState(savedInstanceState);
    if (savedInstanceState != null) {
        // Restore value of members from saved state
        fileLastSync = savedInstanceState.getString("FileLastSync");
    } else {
        //Gets the current DateTime
        long nextTime = (System.currentTimeMillis());
        Date date = new Date(nextTime);

        //Formats the current DateTime
        SimpleDateFormat format = new SimpleDateFormat("MM-dd-yyyy hh:mm a");
        String formatDate = format.format(date);

        //Last sync time is the current formatted date
        fileLastSync = formatDate;

    }

}

}

EDIT: I tried to put this: super.onSaveInstanceState(savedInstanceState); at the end of the method but still doesn't work.

Answer 1

Override onRestoreInstanceState(Bundle savedInstanceState) to restore the date there.

Also, in your onSaveInstanceState method call 'super.onSaveInstanceState` as the last statement.

Answer 2

You should not put in the same code from onSave into onRestore. Copy the complete if-statement from your onCreate method into the onRestore method instead. And call super.onRestoreInstanceState as the first statement.

Edit: sorry - was intended to be a comment