A common mistake that I have seen in many games developed by using Cocos2d-x is that the game does nothing when the back button is pressed. Android users are used to pressing the back button whenever they want to go back to the previous activity. If the application does nothing when the back button is pressed, then it would confuse the user because it would not be an expected behavior, less experienced users may even have a hard time trying to exit the game.

We can easily trigger a custom code any time the user presses the back button by adding an EventListenerKeyboard method to our event dispatcher.

First we are going to add the initBackButtonListener and onKeyPressed method declarations in our HelloWorldScene.h header file, as shown in the following code listing:

void initBackButtonListener();
void onKeyPressed(cocos2d::EventKeyboard::KeyCode keyCode, cocos2d::Event* event);

Now, let us add the implementation code for our initBackButtonListener in...