[Solved] Crashing android application [duplicate]

by 


    public void onClick(View v) {
        AlertDialog.Builder a_builder = new AlertDialog.Builder(MainActivity.this);
        a_builder.setCancelable(false);
        a_builder.setTitle("Alert !");
        a_builder.setMessage("do you want to call!!!");
        a_builder.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                //handle the permission at start.
                if (ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.CALL_PHONE) != PackageManager.PERMISSION_GRANTED) {
                    //permission not granted, ask for permission
                    return;
                }

                Intent callIntent = new Intent(Intent.ACTION_CALL);
                callIntent.setData(Uri.parse("tel:0000000000"));
                startActivity(callIntent);
            }
        });

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

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

    }
});

solved Crashing android application [duplicate]