关于cocos2dx的背景音乐和音效（2）

上回我分享了音频的那些用法，这次来讲一些怎么用滑动条来控制音频。
首先要新建个标题，以及自己找些控制的图片按钮，下面是初始化按钮的代码。

autolabhead=Label::createWithSystemFont("Option","华文楷体",60); //标题
labhead->setTextColor(Color4B::WHITE);
labhead->setPosition(Point(Director::getInstance()->getWinSize().width/2,
Director::getInstance()->getWinSize().height/2+250));
this->addChild(labhead);

autolabmusic=Label::createWithSystemFont("Music","华文楷体",25); //music
labmusic->setTextColor(Color4B::WHITE);
labmusic->setPosition(Point(Director::getInstance()->getWinSize().width/2-280,
Director::getInstance()->getWinSize().height/2+100));
this->addChild(labmusic);

autolabsound=Label::createWithSystemFont("Sound","华文楷体",25); //sound
labsound->setTextColor(Color4B::WHITE);
labsound->setPosition(Point(Director::getInstance()->getWinSize().width/2-280,
Director::getInstance()->getWinSize().height/2-100));
this->addChild(labsound);

btnback=Button::create("option/back1.png","option/back2.png"); //返回按钮
btnback->setScale(0.1);
btnback->setPosition(Point(Director::getInstance()->getWinSize().width-160,
Director::getInstance()->getWinSize().height-100));
this->addChild(btnback);

btnmusic=Button::create("option/music1.png","option/music2.png");
//音乐按钮
btnmusic->setScale(0.1);
btnmusic->setPosition(Point(Director::getInstance()->getWinSize().width/2+300,
Director::getInstance()->getWinSize().height/2+100));
this->addChild(btnmusic);

btnsound=Button::create("option/sound1.png","option/sound2.png"); //音效按钮
btnsound->setScale(0.1);
btnsound->setPosition(Point(Director::getInstance()->getWinSize().width/2+300,
Director::getInstance()->getWinSize().height/2-100));
this->addChild(btnsound);

然后在新建两个滚动条，一个是音乐控制，一个是音效控制。

music_slider=Slider::create();
music_slider->loadBarTexture("option/sliderTrack.png");
music_slider->loadSlidBallTextures("option/sliderThumb.png","option/sliderThumb.png","");
music_slider->loadProgressBarTexture("option/sliderProgress.png");
//float musicpercent =UserDefault::getInstance()->getFloatForKey("musicPercent");
floatmusicpercent1=0;
if(musicpercent1==0.0f)
{
musicpercent1=100.0f;
}
music_slider->setPercent(musicpercent1);
music_slider->setPosition(Point(Director::getInstance()->getWinSize().width/2,
Director::getInstance()->getWinSize().height/2+100));
this->addChild(music_slider);

//音效
musiceffect_slider=Slider::create();
musiceffect_slider->loadBarTexture("option/sliderTrack.png");
musiceffect_slider->loadSlidBallTextures("option/sliderThumb.png","option/sliderThumb.png","");
musiceffect_slider->loadProgressBarTexture("option/sliderProgress.png");
//float musicpercent = UserDefault::getInstance()->getFloatForKey("musicPercent");
floatmusicpercent2=0;
if(musicpercent2==0.0f)
{
musicpercent2=100.0f;
}
musiceffect_slider->setPercent(musicpercent2);
musiceffect_slider->setPosition(Point(Director::getInstance()->getWinSize().width/2,
Director::getInstance()->getWinSize().height/2-100));
this->addChild(musiceffect_slider);

新建所有按钮和滑动条之后，接下来就是实现功能了，先设置按钮的监听事件，点击以后静音，再次点击开启声音。

btnback->addClickEventListener([=](Ref*sender){ //返回主界面
SimpleAudioEngine::getInstance()->playEffect("music/buttoneffect.mp3");
Director::getInstance()->popScene();
});

btnmusic->addClickEventListener([=](Ref*sender){ //静音换图
floatmusicv=SimpleAudioEngine::getInstance()->getBackgroundMusicVolume();
SimpleAudioEngine::getInstance()->playEffect("music/buttoneffect.mp3");
if(musicv!=0)
{
SimpleAudioEngine::getInstance()->setBackgroundMusicVolume(0);
music_slider->setPercent(0);
btnmusic->loadTextureNormal("option/music3.png");
}
if(musicv==0)
{
SimpleAudioEngine::getInstance()->setBackgroundMusicVolume(1);
music_slider->setPercent(100);
btnmusic->loadTextureNormal("option/music1.png");
}
});

btnsound->addClickEventListener([=](Ref*sender){ //静音效换图
SimpleAudioEngine::getInstance()->playEffect("music/buttoneffect.mp3");
floatsoundv=SimpleAudioEngine::getInstance()->getEffectsVolume();
if(soundv!=0)
{
SimpleAudioEngine::getInstance()->setEffectsVolume(0);
musiceffect_slider->setPercent(0);
btnsound->loadTextureNormal("option/sound3.png");
}
if(soundv==0)
{
SimpleAudioEngine::getInstance()->setEffectsVolume(1);
musiceffect_slider->setPercent(100);
btnsound->loadTextureNormal("option/sound1.png");
}

});

接下来设置滑动条同步设置声音的大小。

music_slider->addEventListener([=](Ref*pSender,Slider::EventTypetype)
{
if(type==Slider::EventType::ON_PERCENTAGE_CHANGED)
{
floatpece1=music_slider->getPercent();
SimpleAudioEngine::getInstance()->setBackgroundMusicVolume(pece1/100.0);
//UserDefault::getInstance()->setFloatForKey("musicPercent",pece);
if(pece1==0)
{
btnmusic->loadTextureNormal("option/music3.png");
}
else
{
btnmusic->loadTextureNormal("option/music1.png");
}
}
});

musiceffect_slider->addEventListener([=](Ref*pSender,Slider::EventTypetype)
{
if(type==Slider::EventType::ON_PERCENTAGE_CHANGED)
{
floatpece2=musiceffect_slider->getPercent();
SimpleAudioEngine::getInstance()->setEffectsVolume(pece2/100.0);
//UserDefault::getInstance()->setFloatForKey("musicPercent",pece);
if(pece2==0)
{
btnsound->loadTextureNormal("option/sound3.png");
}
else
{
btnsound->loadTextureNormal("option/sound1.png");
}
}
});

这样就完成了我们控制声音的界面了。在这里我们用上一回的语句加入背景音乐和音效之后，就可已经在这个设置页面上面控制音效的大小和开关啦！（如果不会的话，请看我的这个博客：http://blog.csdn.net/shenmirenlcy/article/details/50054625）

下面是运行的结果，请看图片。





不过如果实在cocos2dx 3.6的版本中的话，可能你会发现貌似无法控制声音的大小，只能控制声音的开关，这个是因为在系统的函数里面，居然是空的........下一篇我再来分享一下怎么把里面的代码补全咯。