6.8.10. Method showGameOverDialog

When the game ends, the showGameOverDialog method (Fig. 6.16) displays a DialogFragment (using the techniques you learned in Section 5.6.9) containing an AlertDialog that indicates whether the player won or lost, the number of shots fired and the total time elapsed. The call to method setPositiveButton (lines 433–444) creates a reset button for starting a new game.

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414      // display an AlertDialog when the game ends
415      private void showGameOverDialog(final int messageId)
416      {
417         // DialogFragment to display quiz stats and start new quiz
418         final DialogFragment gameResult =
419            new DialogFragment()
420            {
421               // create an AlertDialog and return it
422               @Override
423               public Dialog onCreateDialog(Bundle bundle)
424               {
425                  // create dialog displaying String resource for messageId
426                  AlertDialog.Builder builder =
427                     new AlertDialog.Builder(getActivity());
428                  builder.setTitle(getResources().getString(messageId));
429
430                  // display number of shots fired and total time elapsed
431                  builder.setMessage(getResources().getString(
432                     R.string.results_format, shotsFired, totalElapsedTime));
433                  builder.setPositiveButton(R.string.reset_game,
434                     new DialogInterface.OnClickListener()
435                     {
436                        // called when "Reset Game" Button is pressed
437                        @Override
438                        public void onClick(DialogInterface dialog, int which)
439                        {
440                            dialogIsDisplayed = false;
441                            newGame(); // set up and start a new game
442                        }
443                     } // end anonymous inner class
444                  ); // end call to setPositiveButton
445
446                  return builder.create(); // return the AlertDialog
447               } // end method onCreateDialog
448            }; // end DialogFragment anonymous inner class
449
450         // in GUI thread, use FragmentManager to display the DialogFragment
451         activity.runOnUiThread (
452            new Runnable() {
453               public void run()
454               {
455                  dialogIsDisplayed = true;
456                  gameResult.setCancelable(false); // modal dialog          
457                  gameResult.show(activity.getFragmentManager(), "results");
458               }
459            } // end Runnable
460         ); // end call to runOnUiThread
461      } // end method showGameOverDialog
462

Fig. 6.16 | CannonView method showGameOverDialog.

The onClick method of the button’s listener indicates that the dialog is no longer displayed and calls newGame to set up and start a new game. A dialog must be displayed from the GUI thread, so lines 451–460 call Activity method runOnUiThread to specify a Runnable that should execute in the GUI thread as soon as possible. The argument is an object of an anonymous inner class that implements Runnable. The Runnable’s run method indicates that the dialog is displayed and then displays it.