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安卓自定义 View 与动画实现
自定义 View 和动画能显著提升应用的用户体验，以下是 Java 实现的核心技术：

1. 自定义 View 基础
   java
   public class CustomView extends View {
   private Paint paint;
   private Path path;

   public CustomView(Context context) {
   super(context);
   init();
   }

   public CustomView(Context context, AttributeSet attrs) {
   super(context, attrs);
   init();
   }

   private void init() {
   paint = new Paint();
   paint.setColor(Color.RED);
   paint.setStyle(Paint.Style.FILL);
   path = new Path();
   }

   @Override
   protected void onDraw(Canvas canvas) {
   super.onDraw(canvas);
   int width = getWidth();
   int height = getHeight();

    path.moveTo(width/2, 0);
    path.lineTo(width, height);
    path.lineTo(0, height);
    path.close();
    
    canvas.drawPath(path, paint);
   

   }
   }

2. 属性动画实现
   java
   ObjectAnimator animator = ObjectAnimator.ofFloat(view, "translationY", 0f, 200f);
   animator.setDuration(1000);
   animator.setInterpolator(new AccelerateDecelerateInterpolator());
   animator.setRepeatCount(ObjectAnimator.INFINITE);
   animator.setRepeatMode(ObjectAnimator.REVERSE);
   animator.start();

3. 组合动画
   java
   AnimatorSet set = new AnimatorSet();
   ObjectAnimator scaleX = ObjectAnimator.ofFloat(view, "scaleX", 1f, 1.5f);
   ObjectAnimator scaleY = ObjectAnimator.ofFloat(view, "scaleY", 1f, 1.5f);
   ObjectAnimator alpha = ObjectAnimator.ofFloat(view, "alpha", 1f, 0.5f);

set.play(scaleX).with(scaleY).before(alpha);
set.setDuration(1000);
set.start();