Alert Dialog disappers

Question

Alert Dialog disappears when the back button is clicked. Does no give me the opportunity to make a selection. This dialog is suppose to pop up when m == null || m.getPosition() == null. "m" is the variable"Marker m"

@Override
public void onBackPressed() {

    HabitEventController hec = new HabitEventController(this);

    if(m != null && m.getPosition() != null){
        hec.setHabitEventLocation(heID, m.getPosition());
   }

   if(m == null || m.getPosition() == null){
       new AlertDialog.Builder(this)
               .setTitle("Really Exit?")
               .setMessage("Are you sure you want to exit, without creating a marker?")
               .setNegativeButton(android.R.string.no, null)
               .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
                   public void onClick(DialogInterface dialog, int whichButton) {
                       dialog.dismiss();
                       MapsActivity.super.onBackPressed();
                   }
               }).show();
   }

//Remove this call because your app will close and crash before display the dialog
   // finish();
}

Do you know what value does `m` holds?? and that check makes sense, your `m` is not equal to `null` so its skipping the code inside of it. — Mohammed Farhan, Dec 01 '17 at 04:59
The code works. My problems is with the dialog box disappearing to quickly. — pennyBoy, Dec 01 '17 at 05:06

score 0 · Answer 1 · answered Dec 01 '17 at 05:11

0

You have to check in this place with debug mode

 if(m == null || m.getPosition() == null)

here only the problem.

answered Dec 01 '17 at 05:11

Raja

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ADM · Answer 2 · 2017-12-01T05:36:18.590

first of all You are checking wrong condition see

if(m == null || m.getPosition() == null)

1. if m is null then the second condition will throw NullPointerException as you are calling getPosition() on a null object.

You are using ||(Or) in If condition with (m==null) check, which is totally wrong .

First you make it right the If statement then the following code will work in your scenario.

 new AlertDialog.Builder(this)
                .setTitle("Really Exit?")
                .setMessage("Are you sure you want to exit, without creating a marker?")
                .setNegativeButton(android.R.string.no, null)
                .setCancelable(false)
                .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int whichButton) {

                    }
                }).show();

To check Marker in your scenario its better to create a method like this one :

   private boolean isMarkerAvailable() {
    if (m == null)
        return false;
    else if (m.getPosition() == null)
        return false;
    return true;
}

 if (!isMarkerAvailable()) {
        // Show your alert here or you can toggle 
        // the condition whatever is apropriate in your scenario
    }

I'm sorry, I don't see any other way, you would check to see if there are no markers on the map. — pennyBoy, Dec 01 '17 at 05:23

Alert Dialog disappers

2 Answers2

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