本文实例为大家分享了SurfaceView播放视频发送弹幕，并实现滚动歌词，供大家参考，具体内容如下
SurfaceView使用步骤
使用SurfaceView的步骤：
- 首先要继承SurfaceView，实现SurfaceHolder.Callback接口。
- 重写方法：surfaceChanged：surface大小或格式发生变化时触发，在surfaceCreated调用后该函数至少会被调用一次。
- surfaceCreated：Surface创建时触发，一般在这个函数开启绘图线程（新的线程，不要再这个线程中绘制Surface）。
- surfaceDestroyed：销毁时触发，一般不可见时就会销毁。
- 利用getHolder()获取SurfaceHolder对象，调用SurfaceHolder.addCallback添加回调
- SurfaceHolder.lockCanvas 获取Canvas对象并锁定画布，调用Canvas绘图，SurfaceHolder.unlockCanvasAndPost 结束锁定画布，提交改变。
SurfaceHolder
SurfaceHolder回调自己的三个生命周期：
- surfaceCreated(SurfaceHolder holder)创建时
- surfaceChanged(SurfaceHolder holder,int format,int width,int height)改变时
- surfaceDestroyed(SurfaceHolder holder)销毁时
SurfaceView播放视频并可以发送弹幕
需要准备两个SurfaceView，一个是负责播放视频，一个负责展示弹幕。弹幕是展示在视频上面的，所以我们要给展示弹幕的SurfaceView设置两个方法：
surfaceView_danmu.setZOrderOnTop(true); ——置于上方
surfaceView_danmuHolder.setFormat(PixelFormat.TRANSPARENT); ——背景透明
public class MainActivity extends AppCompatActivity implements SurfaceHolder.Callback {
public static final int PROGRESS = 101;
SurfaceView surfaceView,surfaceView_danmu;
SurfaceHolder surfaceHolder,surfaceView_danmuHolder;
MediaPlayer mediaPlayer = new MediaPlayer();
String path = "/sdcard/aa.mp4";
SeekBar seekBar;
Timer timer;
EditText editText;
Button button,bt_start,bt_stop;
int x = 0;
ArrayList<DanMu> list = new ArrayList<>();
Handler handler = new Handler(){
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
if (msg.what == PROGRESS){
seekBar.setProgress((Integer) msg.obj);
mediaPlayer.setOnSeekCompleteListener(new MediaPlayer.OnSeekCompleteListener() {
@Override
public void onSeekComplete(MediaPlayer mp) {
Toast.makeText(MainActivity.this,"播放完毕！",Toast.LENGTH_SHORT).show();
}
});
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
surfaceView = findViewById(R.id.sufaceview);
surfaceView_danmu = findViewById(R.id.sufaceview_danmu);
editText = findViewById(R.id.et);
button = findViewById(R.id.bt_send);
seekBar = findViewById(R.id.bar);
bt_start = findViewById(R.id.bt_start);
bt_stop = findViewById(R.id.bt_stop);
surfaceHolder = surfaceView.getHolder();
surfaceHolder.addCallback(this);
surfaceView_danmuHolder = surfaceView_danmu.getHolder();
surfaceView_danmuHolder.addCallback(this);
surfaceView_danmu.setZOrderOnTop(true);
surfaceView_danmuHolder.setFormat(PixelFormat.TRANSPARENT);
if (mediaPlayer!=null) {
try {
mediaPlayer.setDataSource(path);
mediaPlayer.prepareAsync();
mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
@Override
public void onPrepared(MediaPlayer mp) {
mediaPlayer.start();
int duration = mediaPlayer.getDuration();
seekBar.setMax(duration);
timer = new Timer();
timer.schedule(new TimerTask() {
@Override
public void run() {
int currentPosition = mediaPlayer.getCurrentPosition();
Message message = Message.obtain();
message.what = PROGRESS;
message.obj = currentPosition;
handler.sendMessage(message);
}
},1000);
}
});
seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar,int progress,boolean fromUser) {
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
int progress = seekBar.getProgress();
mediaPlayer.seekTo(progress);
}
});
} catch (IOException e) {
e.printStackTrace();
}
}
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
String s = editText.getText().toString();
int y= (int) (Math.random()*300);
list.add(new DanMu(0,y,s,Color.RED));
}
});
bt_start.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mediaPlayer.start();
}
});
bt_stop.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mediaPlayer.pause();
}
});
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
if (holder == surfaceHolder) {
mediaPlayer.setDisplay(holder);
}else if (holder == surfaceView_danmuHolder) {
new MyDanMuThread().start();
}
}
@Override
public void surfaceChanged(SurfaceHolder holder,int height) {
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
}
class MyDanMuThread extends Thread {
@Override
public void run() {
super.run();
Paint paint = new Paint();
paint.setColor(Color.RED);
paint.setTextSize(40);
while (true) {
try {
Thread.sleep(200);
} catch (InterruptedException e) {
e.printStackTrace();
}
Canvas canvas = surfaceView_danmuHolder.lockCanvas();
canvas.drawColor(Color.TRANSPARENT,PorterDuff.Mode.CLEAR);
for (int i=0;i<list.size();i++) {
DanMu danMu = list.get(i);
x = danMu.getX();
danMu.setX(x+=10);
canvas.drawText(danMu.getText(),danMu.getX(),danMu.getY(),paint);
}
surfaceView_danmuHolder.unlockCanvasAndPost(canvas);
}
}
}
}
实现滚动歌词
要准备一个装有时间和歌词的集合，准备一个Timer计时器和一个该展示第几个歌词。每隔一秒去拿该歌词的下一个歌词时间与进度匹配，如果进度>=该时间，那么就画该歌词在SurfaceView上；<则不画该歌词
一定要写SD卡读写权限！！！！！
public class MainActivity extends AppCompatActivity implements SurfaceHolder.Callback{
SurfaceView surfaceView;
SurfaceHolder surfaceHolder;
MediaPlayer mediaPlayer = new MediaPlayer();
ArrayList<Music> list=new ArrayList<>();
Timer timer;
int count = 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
surfaceView = findViewById(R.id.sv);
surfaceHolder=surfaceView.getHolder();
surfaceHolder.addCallback(this);
timer = new Timer();
timer.schedule(new TimerTask() {
@Override
public void run() {
int currentPosition = mediaPlayer.getCurrentPosition();
if(list.size()>0){
if(currentPosition>=list.get(count+1).getTime()){
count++;
}
}
}
},500);
try {
mediaPlayer.setDataSource("/sdcard/凤凰传奇 - 最炫民族风(Live).mp3");
mediaPlayer.prepareAsync();
mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
@Override
public void onPrepared(MediaPlayer mp) {
mediaPlayer.start();
}
});
} catch (IOException e) {
e.printStackTrace();
}
try {
StringBuffer stringBuffer = new StringBuffer();
FileInputStream fileInputStream = new FileInputStream("/sdcard/最炫民族风");
byte[] bytes = new byte[1024];
int len = 0;
while ((len=fileInputStream.read(bytes))!=-1) {
stringBuffer.append(new String(bytes,len));
}
Gson gson = new Gson();
JavaBean javaBean = gson.fromJson(stringBuffer.toString(),JavaBean.class);
JavaBean.LrcBean lrc = javaBean.getLrc();
String lyric = lrc.getLyric();
String[] split = lyric.split("\n");
for(int i=0;i<split.length;i++){
String trim = split[i].trim();
String[] split1 = trim.split("]");
if(split.length>=2){
String s = split1[0];
String substring1 = s.substring(1,3);
String substring2 = s.substring(4,6);
String substring3 = s.substring(7,10);
long start = Integer.parseInt(substring1)*60*1000+Integer.parseInt(substring2)*1000+Integer.parseInt(substring3);
String text = split1[1];
list.add(new Music(text,start));
}
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
new MyThread().start();
}
@Override
public void surfaceChanged(SurfaceHolder holder,int height) {
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
}
class MyThread extends Thread {
@Override
public void run() {
super.run();
Paint paint = new Paint();
paint.setColor(Color.RED);
paint.setTextSize(50);
while (true){
try {
Thread.sleep(100);
} catch (InterruptedException e) {
e.printStackTrace();
}
Canvas canvas = surfaceHolder.lockCanvas();
if(canvas==null){
break;
}
canvas.drawColor(Color.TRANSPARENT,PorterDuff.Mode.CLEAR);
if(list.size()>0){
canvas.drawText(list.get(count).getTitle(),100,paint);
}
surfaceHolder.unlockCanvasAndPost(canvas);
}
}
}
}
