showing alert dialog on pressing back button

Question

I want to show an alert message on pressing back button of Android device asking user weather he is sure or not. If user press "Yes" then he should navigate to previous. in case of "NO" activity should resume. But the problem occurs when I press back button it performs both the actions. It also navigate to previous activity and displays the alert dialog.

Here is my code.

public void onBackPressed() {

    super.onBackPressed();

    AlertDialog.Builder alertdialog=new AlertDialog.Builder(this);
    alertdialog.setTitle("Warning");
    alertdialog.setMessage("Are you sure you Want to exit the tutorial???");
    alertdialog.setPositiveButton("yes", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            Intent intent=new Intent(secAddition.this,addition.class);
            startActivity(intent);
            secAddition.this.finish();
        }
    });

    alertdialog.setNegativeButton("No", new DialogInterface.OnClickListener(){
        @Override
        public void onClick(DialogInterface dialog, int which) {
            dialog.cancel();
        }
    });

    AlertDialog alert=alertdialog.create();
    alertdialog.show();

}

dont call startActivity on BackPress. you should call super OnBackPress. when hardware back is pressed. check my answer. — Developine, May 17 '16 at 12:38

score 10 · Answer 1 · answered May 17 '16 at 12:30

10

If you want to show the alert dialog without closing the app or clearing the stack, you should not call super.onBackPressed();

answered May 17 '16 at 12:30

Seishin

1,493
1
19
30

it's simple, short and correct answer – anhtuannd Feb 13 '19 at 09:06

score 3 · Accepted Answer · edited Apr 15 '19 at 12:23

Please check the following code snippet

 @Override
 public void onBackPressed() {
     //super.onBackPressed();
     IsFinish("Want to close app?");
 }

 public void IsFinish(String alertmessage) {

      DialogInterface.OnClickListener dialogClickListener = new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {

                    switch (which) {
                        case DialogInterface.BUTTON_POSITIVE:
                            android.os.Process.killProcess(android.os.Process.myPid());
                            // This above line close correctly
                            //finish();
                            break;

                        case DialogInterface.BUTTON_NEGATIVE:  
                            break;
                    }
                }
            };

      AlertDialog.Builder builder = new AlertDialog.Builder(context);
      builder.setMessage(alertmessage)
                .setPositiveButton("Yes", dialogClickListener)
                .setNegativeButton("No", dialogClickListener).show();

 }

score 2 · Answer 3 · edited Apr 15 '19 at 12:32

Remove

super.onBackPressed();

This should work.

public void onBackPressed() {

   AlertDialog.Builder alertdialog=new AlertDialog.Builder(this);
   alertdialog.setTitle("Warning");
   alertdialog.setMessage("Are you sure you Want to exit the tutorial???");
   alertdialog.setPositiveButton("yes", new DialogInterface.OnClickListener(){
       @Override
       public void onClick(DialogInterface dialog, int which) {
           Intent intent=new Intent(secAddition.this,addition.class);
           startActivity(intent);
           secAddition.this.finish();
       }
    });

   alertdialog.setNegativeButton("No", new DialogInterface.OnClickListener() {
       @Override
       public void onClick(DialogInterface dialog, int which) {
            dialog.cancel();
       }
   });

   AlertDialog alert=alertdialog.create();
   alertdialog.show();

}

kindly mark as answer . – Sathish Kumar J May 17 '16 at 14:44 — Sathish Kumar J, May 17 '16 at 14:44

score 2 · Answer 4 · edited Apr 15 '19 at 12:28

This is what you are looking for. you don't need to startActivity on back pressed. If user select Yes than call super onBackPress

public void onBackPressed() {

   AlertDialog.Builder alertdialog=new AlertDialog.Builder(this);
   alertdialog.setTitle("Warning");
   alertdialog.setMessage("Are you sure you Want to exit the tutorial???");
   alertdialog.setPositiveButton("yes", new DialogInterface.OnClickListener(){

      @Override
      public void onClick(DialogInterface dialog, int which) {
         super.onBackPressed();
      }
    });

    alertdialog.setNegativeButton("No", new DialogInterface.OnClickListener(){

      @Override
      public void onClick(DialogInterface dialog, int which) {
         dialog.cancel();
      }

    });

    AlertDialog alert=alertdialog.create();
    alertdialog.show();

}

score 1 · Answer 5 · edited Apr 15 '19 at 12:33

you can write like this for your code to work :

public void onBackPressed() {

     AlertDialog.Builder alertdialog=new AlertDialog.Builder(this);
     alertdialog.setTitle("Warning");
     alertdialog.setMessage("Are you sure you Want to exit the tutorial???");
     alertdialog.setPositiveButton("yes", new DialogInterface.OnClickListener() {
           @Override
           public void onClick(DialogInterface dialog, int which) {
                 super.onBackPressed();    
           }
     });

    alertdialog.setNegativeButton("No", new DialogInterface.OnClickListener(){
           @Override
           public void onClick(DialogInterface dialog, int which) {
                 dialog.cancel();
           }
    });

    AlertDialog alert=alertdialog.create();
    alertdialog.show();

}

No need to start the Activity again if you are going to previous Activity,

In your code when you do a back press, super.onBackPressed() gets called so it goes to previous Activity

showing alert dialog on pressing back button

5 Answers5