Your First Game – Air Hockey - Cocos2d-x by Example Beginner's Guide - page 61

Time for action - adding the sound files
Assuming you have the sound files from the downloaded resources, let's add them to the
project.
1. Drag both the .wav files to the Resources folder inside your Project folder.
2. Then go to Xcode, select the Resources folder in the file navigation panel and
select File | Add Files to AirHockey .
3. Make sure the AirHockey target is selected.
4. Go to AppDelegate.cpp again. At the top, add this include statement:
#include "SimpleAudioEngine.h"
5. Then below the USING_NS_CC macro (for using namespace cocos2d ),
add:
using namespace CocosDenshion;
6. Then just below the lines you added in the previous section, inside applica-
tionDidFinishLaunching , add the following lines:
auto audioEngine = SimpleAudioEngine::getInstance();
audioEngine->preloadEffect(
fileUtils->fullPathForFilename("hit.wav").c_str() );
audioEngine->preloadEffect(
fileUtils->fullPathForFilename("score.wav").c_str() );
audioEngine->setBackgroundMusicVolume(0.5f);
audioEngine->setEffectsVolume(0.5f);