Android自定义View实现圆环交替效果

<?xml version="1.0" encoding="utf-8"?>
<resources>
 
 <attr name="firstColor" format="color"/>
 <attr name="secondColor" format="color"/>
 <attr name="circleWidth" format="dimension"/>
 <attr name="speed" format="integer"/>
 
 <declare-styleable name="CustomView">
  <attr name="firstColor" />
  <attr name="secondColor" />
  <attr name="circleWidth" />
  <attr name="speed" />
 </declare-styleable>
 
</resources>

public class MySelfCircleView extends View {
 
 /*
  * 第一圈颜色
  */
 int firstColor;
 /*
  * 第二圈颜色
  */
 int secondColor;
 /*
  * 圆的宽度
  */
 int circleWidth;
 /*
  * 速率
  */
 int speed;
 /*
  * 画笔
  */
 Paint mPaint;
 /*
  * 进度
  */
 int mProgress;
 /*
  * 是否切换标志
  */
 boolean isNext;
 
 public MySelfCircleView(Context context, AttributeSet attrs,
   int defStyleAttr) {
  super(context, attrs, defStyleAttr); 
  TypedArray typedArray = context.getTheme().obtainStyledAttributes(attrs, R.styleable.CustomView, defStyleAttr, 0);
  int n = typedArray.getIndexCount();
  for(int i=0; i<n; i++){
   int attr = typedArray.getIndex(i);
   switch (attr) {
    case R.styleable.CustomView_firstColor:
     firstColor = typedArray.getColor(attr, Color.RED);
     break;
    case R.styleable.CustomView_secondColor:
     secondColor = typedArray.getColor(attr, Color.RED);
     break;
    case R.styleable.CustomView_circleWidth:
     circleWidth = typedArray.getDimensionPixelSize(attr, (int) TypedValue.applyDimension( 
       TypedValue.COMPLEX_UNIT_PX, 20, getResources().getDisplayMetrics())); 
     break;
    case R.styleable.CustomView_speed:
     speed = typedArray.getInt(attr, 20);
     break;
   }
  }
  typedArray.recycle();
  
  mPaint = new Paint();
  new Thread(new Runnable() {
   @Override
   public void run() {
    while (true) {
     mProgress++;
     if (mProgress == 360) { 
      mProgress = 0; 
      if (!isNext) 
       isNext = true; 
      else 
       isNext = false; 
     } 
     postInvalidate(); 
     try { 
      Thread.sleep(speed); 
     } catch (InterruptedException e) { 
      e.printStackTrace(); 
     } 
    }
   }
  }).start();
 }

 public MySelfCircleView(Context context, AttributeSet attrs) {
  this(context, attrs, 0);
 }

 public MySelfCircleView(Context context) {
  this(context, null);
 }
 
 @Override
 protected void onDraw(Canvas canvas) {
  super.onDraw(canvas);
  int centre = getWidth() / 2; // 获取圆心的x坐标 
  int radius = centre - circleWidth / 2;// 半径 
  mPaint.setStrokeWidth(circleWidth); // 设置圆环的宽度 
  mPaint.setAntiAlias(true); // 消除锯齿 
  mPaint.setStyle(Paint.Style.STROKE); // 设置空心 
  RectF oval = new RectF(centre - radius, centre - radius, centre + radius, centre + radius); // 用于定义的圆弧的形状和大小的界限 
  if (!isNext) {// 第一颜色的圈完整，第二颜色跑 
   mPaint.setColor(firstColor); // 设置圆环的颜色 
   canvas.drawCircle(centre, centre, radius, mPaint); // 画出圆环 
   mPaint.setColor(secondColor); // 设置圆环的颜色 
   canvas.drawArc(oval, -90, mProgress, false, mPaint); // 根据进度画圆弧 
  } else { 
   mPaint.setColor(secondColor); // 设置圆环的颜色 
   canvas.drawCircle(centre, centre, radius, mPaint); // 画出圆环 
   mPaint.setColor(firstColor); // 设置圆环的颜色 
   canvas.drawArc(oval, -90, mProgress, false, mPaint); // 根据进度画圆弧 
  }
 }
 
}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:zhy="http://schemas.android.com/apk/res/com.example.myselfview"
 android:layout_width="match_parent"
 android:layout_height="match_parent" >
 
 <com.example.myselfview.view.MySelfCircleView 
  android:layout_width="120dp"
  android:layout_height="120dp"
  android:layout_marginTop="20dp"
  android:layout_alignParentTop="true"
  android:layout_centerHorizontal="true"
  zhy:circleWidth="15dp"
  zhy:firstColor="#D4F668"
  zhy:secondColor="#2F9DD2"
  zhy:speed="10" /> 
 
 <com.example.myselfview.view.MySelfCircleView 
  android:layout_width="200dp"
  android:layout_height="200dp"
  android:layout_alignParentBottom="true"
  android:layout_centerHorizontal="true"
  zhy:circleWidth="24dp"
  android:layout_marginBottom="40dp"
  zhy:firstColor="#16A3FA"
  zhy:secondColor="#D20F02"
  zhy:speed="5" /> 
 
</RelativeLayout>