eventbus的使用与学习

首先贴个地址

https://github.com/greenrobot/EventBus

Android EventBus是基于事件驱动的一个开源库，也算是一个观察者模式Observe，扩展性强使用简单，用发布者和订阅者很好的解决了两个模块之间的通信，如Fragment和Activity，Activity和Service之间的通信啊，支持自定义消息类型来传输，最近公司的一个项目控制音乐的播放，我也用到了EventBus，由Activity向Service发送消息，Service来控制音乐曲目的播放，代码片段

Service

public void onEventBackgroundThread(MyEvent event){

    Log.e("TAGEVENT",event.getPath());

    if (event.getPath()=="null")
    {

        if (mPlayer.isPlaying()==false)
        {
            int r=new Random().nextInt(8);
            Log.e("TAGRANDOM",""+r);
            mPlayer.reset();//idle
            try
            {
                mPlayer.setDataSource("/storage/emulated/legacy/res/common/sound/"+musicesource[r]+".mp3");
                mPlayer.prepare();
                mPlayer.start();
            }
            catch (IllegalArgumentException e)
            {
                e.printStackTrace();
            }
            catch (SecurityException e)
            {
                e.printStackTrace();
            }
            catch (IllegalStateException e)
            {
                e.printStackTrace();
            }
            catch (IOException e)
            {
                e.printStackTrace();
            }

        }
        else
        {
            Log.e("TAGP","We are Playing ,baby");
        }
    }
    else
    {

        Log.d("harvic", "onEventBackground收到了消息：" + event.getPath());

        mPlayer.reset();//idle
        try
        {
            mPlayer.setDataSource(event.getPath());
            mPlayer.prepare();
            mPlayer.start();
        }
        catch (IllegalArgumentException e)
        {
            e.printStackTrace();
        }
        catch (SecurityException e)
        {
            e.printStackTrace();
        }
        catch (IllegalStateException e)
        {
            e.printStackTrace();
        }
        catch (IOException e)
        {
            e.printStackTrace();
        }
    }



}
public void play()
{
    mPlayer.reset();//idle
    try
    {
        mPlayer.setDataSource(path);
        mPlayer.prepare();
        mPlayer.start();
    }
    catch (IllegalArgumentException e)
    {
        e.printStackTrace();
    }
    catch (SecurityException e)
    {
        e.printStackTrace();
    }
    catch (IllegalStateException e)
    {
        e.printStackTrace();
    }
    catch (IOException e)
    {
        e.printStackTrace();
    }

}

class MediaBinder extends Binder
{
    public void play()
    {
        MediaService.this.play();
    }
}



@Override
public IBinder onBind(Intent intent)
{
    return new MediaBinder();
}

}

Activity

//背景音乐设置————————————————————————————————————————————————————————————————————————————————————————————————————————————————————————————————————————————
if (mScenes.get(position).getBackground_music() == "null") { Log.e("error", "/storage/emulated/legacy/res/common/sound/" + mScenes.get(position).getBackground_music()); EventBus.getDefault().post(new MyEvent("null")); } else { EventBus.getDefault().post(new MyEvent("/storage/emulated/legacy/res/common/sound/" + mScenes.get(position).getBackground_music())); Log.e("bmg", "/storage/emulated/legacy/res/common/sound/" + mScenes.get(position).getBackground_music()); }