android自定义进度圆与定时任务

先看代码：自定进度圆

public class ProgressCircle extends View {

    private Paint paint;
    private int strokewidth = 4;
    private int alpha = 50;
    private int progress = 30;
    private Paint mpaint;

    public ProgressCircle(Context context) {
        super(context,null);
    }

    public ProgressCircle(Context context, AttributeSet attrs) {
        super(context, attrs);

        paint = new Paint();
        paint.setColor(Color.BLACK);
        paint.setDither(true);
        paint.setAntiAlias(true);
        paint.setStrokeCap(Paint.Cap.ROUND);
        paint.setStrokeJoin(Paint.Join.ROUND);
        paint.setStrokeWidth(strokewidth);
        paint.setStyle(Paint.Style.STROKE);
        paint.setAlpha(alpha);

        mpaint = new Paint();
        mpaint.setColor(Color.RED);
        mpaint.setDither(true);
        mpaint.setAntiAlias(true);
        mpaint.setStrokeCap(Paint.Cap.ROUND);
        mpaint.setStrokeJoin(Paint.Join.ROUND);
        mpaint.setStrokeWidth(strokewidth);
        mpaint.setStyle(Paint.Style.STROKE);

    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        int cx = getWidth()/2;
        int cy = getHeight()/2;
        int radius = (cx>cy?cy:cx)-strokewidth;

        canvas.drawCircle(cx,cy,radius,paint);

        RectF oval = new RectF(cx-radius,cy-radius,cx+radius,cy+radius);
        canvas.drawArc(oval,90,(int)(-(3.6)*progress),false,mpaint);
    }

    public  void setprogress( int progresss){
        this.progress = progresss;

        postInvalidate();//这个很重要，不能是Invalidate()；

    }
}

如果是invalidate();则会报错：

android.view.ViewRootImpl$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
at android.view.ViewRootImpl.checkThread(ViewRootImpl.java:6024)
at android.view.ViewRootImpl.invalidateChildInParent(ViewRootImpl.java:853)
at android.view.ViewGroup.invalidateChild(ViewGroup.java:4320)

因为：invalidate是在UI线程中使用，而postInvalidate是在非UI线程中使用的，UI线程中不能做耗时任务；

看MainActivity代码：

public class MainActivity extends AppCompatActivity {

    private ProgressCircle circle;
    private Button load;
    private  int i = 0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        circle = (ProgressCircle) findViewById(R.id.circle);
        load = (Button) findViewById(R.id.load);
        load.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                new Thread(myrunable).start();
            }
        });
    }

    Runnable myrunable = new Runnable() {
        @Override
        public void run() {
//            setdata();

            Timedata();
        }
    };

    private void setdata(){
        for (int j = 0; j < 101; j++) {
            circle.setprogress(j);
            Log.e("tag", "run: "+j );
            try {
                Thread.sleep(100);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    private void Timedata(){
        Timer timer = new Timer();
        final TimerTask task = new TimerTask() {
            @Override
            public void run() {
                circle.setprogress(i);
                Log.e("tag", "run: "+i);
                if (i>99){
                   cancel();
                }
                i++;
            }
        };
        timer.schedule(task,10,100);

    }

    @Override
    protected void onDestroy() {
        super.onDestroy();

    }
}

schedu的参数：timetask是指定时任务，第二个参数是指在在什么事件段内完成，我这里写的是10；第三个peroid是指在延时多少时间执行任务。

demo下载地址：https://github.com/renjiemei1225/ProgressCircle_12_7.git