关于实现类似于圆形ProgressBar的播放进度条
我们要实现一个类似于小米分享中的圆形播放进度条，android自带的圆形ProgressBar是默认自动旋转的，所以无法实现，于是我们想到了使用自定义一个View，来实现这种效果。
首先来看看自己定义的View
packagecn.easymobi.application.bell.common;
importandroid.content.Context;
importandroid.graphics.Canvas;
importandroid.graphics.Color;
importandroid.graphics.Paint;
importandroid.graphics.RectF;
importandroid.util.AttributeSet;
importandroid.view.View;
publicclassProgressViewextendsView{
privatefloatfArcNum;
privatefloatfMax;
privatefloatdensity;
publicfloatgetDensity(){
returndensity;
}
publicvoidsetDensity(floatdensity){
this.density=density;
}
publicProgressView(Contextcontext){
super(context);
}
publicProgressView(Contextcontext,AttributeSetattrs){
super(context,attrs);
}
protectedvoidonDraw(Canvascanvas){
//TODOAuto-generatedmethodstub
super.onDraw(canvas);
Paintpaint=newPaint();
if(fArcNum>0)
{
paint.setColor(Color.GRAY);
paint.setFlags(Paint.ANTI_ALIAS_FLAG);
canvas.drawCircle(40*density/2,40*density/2,40*density/2,paint);}
paint.setColor(Color.YELLOW);
paint.setFlags(Paint.ANTI_ALIAS_FLAG);
//paint.setStrokeWidth(2);
RectFrect=newRectF(0,0,40*density,40*density);
canvas.drawArc(rect,-90,fArcNum,true,paint);
paint.setColor(Color.BLACK);
paint.setFlags(Paint.ANTI_ALIAS_FLAG);
canvas.drawCircle(40*density/2,40*density/2,40*density/2-5,paint);
}
publicvoidsetProgress(floatnum)
{
fArcNum = (num/fMax) * 360;this.postInvalidate();
}
publicfloatgetfArcNum(){
returnfArcNum;
}
publicvoidsetfArcNum(floatfArcNum){
this.fArcNum=fArcNum;
}
publicfloatgetfMax(){
returnfMax;
}
publicvoidsetfMax(floatfMax){
this.fMax=fMax;
}
}使用：
private ProgressView progress;
float num=0;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.clean);
progress=(ProgressView)findViewById(R.id.progress_main_clean);
progress.setDensity(1);
progress.setfMax(100);
Timer timer=new Timer();
MyTask task=new MyTask();
timer.schedule(task,0, 500);
}
class MyTask extends TimerTask{
@Override
public void run() {
// TODO Auto-generated method stub
progress.setProgress(num);
System.out.println("number"+num);
num++;
}
}
我们通过重写View的onDraw方法，根据fArcNum好fMax来判断当前播放到的位置，然后不停的刷新改View就实现了这个效果。至于画弧，是采用了drawArc方法，然后通过在其内部画圆遮盖多余部分实现。
下面是MediaPlayer与该View的同步处理，核心代码如下
//*******************************************************************
//Func:playAudio
//
//by:Sun
//2011.9.1
//*******************************************************************
publicvoidplayAudio(finalStringpath,finalProgressBarpb){
Threadthread=newThread(newRunnable(){
publicvoidrun(){
try{
if(mpMediaPlayer!=null){
mpMediaPlayer.stop();
mpMediaPlayer.release();
mpMediaPlayer=null;
}
mpMediaPlayer=newMediaPlayer();
mpMediaPlayer.setDataSource(path);
mpMediaPlayer.prepare();
mpMediaPlayer
.setOnPreparedListener(newOnPreparedListener(){
publicvoidonPrepared(MediaPlayermp){
pb.setVisibility(ProgressBar.GONE);
frontPv.setfMax(mpMediaPlayer.getDuration());
frontPv.setProgress(0);
mpMediaPlayer.start();
refrash=newThread(newRunnable(){
publicvoidrun(){
try{
while(frontPv.getfArcNum()<=360
&&mpMediaPlayer
.isPlaying()){
if(bIsOver)
break;
frontPv.setProgress(mpMediaPlayer
.getCurrentPosition());
Thread.sleep(1000);
mHandle.sendEmptyMessage(MSG_REFRESH_UI);
}
mHandle.sendEmptyMessage(MSG_PLAY_OVER);
}catch(Exceptione){
e.printStackTrace();
}
}
});
refrash.start();
}
});
}catch(Exceptione){
e.printStackTrace();
}
}
});
thread.start();
}
其中frontPv是我们自己定义的view,最后发送handler是调用invalidate方法刷新该view,mpMediaPlayers是我们定义的MediaPlayer对象。我们通过在进程中每隔一秒更新frontPv当中的fArcNum并且刷新实现转动的动画效果。
原文章出处 http://labs.ywlx.net/?p=1296