content: package com.rsen.github.loadview.indicator;
  
  import android.animation.Animator;
  import android.animation.ValueAnimator;
  import android.graphics.Canvas;
  import android.graphics.Paint;
  
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * Created by Jack on 2015/10/16.
   */
  public class BallPulseIndicator extends BaseIndicatorController{
  
      public static final float SCALE=1.0f;
  
      //scale XUtil ,y
      private float[] scaleFloats=new float[]{SCALE,
              SCALE,
              SCALE};
  
  
  
      @Override
      public void draw(Canvas canvas, Paint paint) {
          float circleSpacing=4;
          float radius=(Math.min(getWidth(),getHeight())-circleSpacing*2)/6;
          float x = getWidth()/ 2-(radius*2+circleSpacing);
          float y=getHeight() / 2;
          for (int i = 0; i < 3; i++) {
              canvas.save();
              float translateX=x+(radius*2)*i+circleSpacing*i;
              canvas.translate(translateX, y);
              canvas.scale(scaleFloats[i], scaleFloats[i]);
              canvas.drawCircle(0, 0, radius, paint);
              canvas.restore();
          }
      }
  
      @Override
      public List<Animator> createAnimation() {
          List<Animator> animators=new ArrayList<>();
          int[] delays=new int[]{120,240,360};
          for (int i = 0; i < 3; i++) {
              final int index=i;
              
              ValueAnimator scaleAnim=ValueAnimator.ofFloat(1,0.3f,1);
              
              scaleAnim.setDuration(750);
              scaleAnim.setRepeatCount(-1);
              scaleAnim.setStartDelay(delays[i]);
              
              scaleAnim.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
                  @Override
                  public void onAnimationUpdate(ValueAnimator animation) {
                      scaleFloats[index] = (float) animation.getAnimatedValue();
                      postInvalidate();
  
                  }
              });
              scaleAnim.start();
              animators.add(scaleAnim);
          }
          return animators;
      }
  
  }
  