android 抛物线下载动画

my.gif

下载动画经常出现在下载需求多的app中，比如游戏下载平台，应用市场。。。

• 实现

private void startAnim() {   
    //以bitmap创建new ImageView
    iv.setDrawingCacheEnabled(true);  
    Bitmap bitmap = iv.getDrawingCache();   
    ImageView logo = new ImageView(this);      
    logo.setScaleType(ImageView.ScaleType.FIT_XY);     
    logo.setImageBitmap(bitmap); 
    int[] startLocation = new int[2];   
    iv.getLocationInWindow(startLocation);   
    //动画结束ImageView   
    end.getLocationInWindow(location_download);  
    setAnim(logo, startLocation, location_download);
}

• 设置动画

private void setAnim(final ImageView logo, int[] startLocation, int[] location_download) {   
  ViewGroup animMaskLayout = createAnimLayout();    
  animMaskLayout.addView(logo);// 把动画小球添加到动画层  
  final View view = addViewToAnimLayout(logo, startLocation);    // 计算位移   
  int endX = location_download[0] - startLocation[0]; // 动画位移的X坐标     
  int endY = location_download[1] - startLocation[1];// 动画位移的y坐标    
  TranslateAnimation translateAnimationX = new TranslateAnimation(0,    endX, 0, 0);   
  translateAnimationX.setInterpolator(new LinearInterpolator());     
  translateAnimationX.setRepeatCount(0);// 动画重复执行的次数    
  translateAnimationX.setFillAfter(true);    TranslateAnimation  
  translateAnimationY = new TranslateAnimation(0, 0, 0, endY);     
  translateAnimationY.setInterpolator(new AccelerateInterpolator());    
  translateAnimationY.setRepeatCount(0);// 动画重复执行的次数    
  translateAnimationX.setFillAfter(true); 
  AnimationSet set = new AnimationSet(false); 
  set.setFillAfter(false);    
  set.addAnimation(translateAnimationY);    
  set.addAnimation(translateAnimationX);  
  set.setDuration(2000);// 动画的执行时间   
  view.startAnimation(set);    // 动画监听事件   
  set.setAnimationListener(new Animation.AnimationListener() {    
        // 动画的开始       
       @Override    
       public void onAnimationStart(Animation animation) {    
              logo.setVisibility(View.VISIBLE);   
     }         
      @Override  
      public void onAnimationRepeat(Animation animation) {   
     }      
      // 动画的结束       
      @Override    
      public void onAnimationEnd(Animation animation) {            
              logo.setVisibility(View.GONE);   
     } 
   });
}

• 创建动画父布局

private ViewGroup createAnimLayout() {
    ViewGroup rootView = (ViewGroup) getWindow().getDecorView();       
    LinearLayout animLayout = new LinearLayout(this);       
    LinearLayout.LayoutParams lp = new  LinearLayout.LayoutParams(
       LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT);    
    animLayout.setLayoutParams(lp);      
    animLayout.setId(Integer.MAX_VALUE);    
    animLayout.setBackgroundResource(android.R.color.transparent);     
    rootView.addView(animLayout);  
    return animLayout;
}

• 设置动画布局参数

private static View addViewToAnimLayout(final View view, int[] location) {   
   int x = location[0]; 
   int y = location[1];   
   LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(80, 80);   
   lp.leftMargin = x;  
   lp.topMargin = y;   
   view.setLayoutParams(lp); 
   return view;
}

代码就到此结束了，看起来并不难，动手试试吧