Android dialog上动画的问题

Question

Activity上有ListView，点击ListView的Item会弹出dialog，点击dialog上的+号演示一个小球从+号飞到Activity底部的购物车的动画，想了好几天无法实现这个动画，要么这个动画是在dialog的后面，要么这个动画只能在dialog的范围内，求大神赐教！谢谢！！
下面贴我的代码

 public class MainActivity extends Activity implements OnClickListener {

    private Button bt;
    private TextView cart;
    private Button add;
    private ImageView photoImageView;
    private Dialog selectDialog;

    private int[] foodAddLocation = new int[2];
    private int[] cartLocation = new int[2];

    private ViewGroup animLayout;//动画层

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

        bt = (Button) findViewById(R.id.bt);
        bt.setOnClickListener(this);
        cart = (TextView) findViewById(R.id.cart);

    }

    public void showSelectDialog() {

        View view = LayoutInflater.from(this).inflate(R.layout.dialog_view, null);

        ImageView close = (ImageView)view.findViewById(R.id.select_close);
        close.setOnClickListener(this);
        add = (Button)view.findViewById(R.id.add);//TODO
        add.setOnClickListener(this);

        TextView nameView = (TextView)view.findViewById(R.id.food_name);
        nameView.setText("哈哈哈");

        photoImageView = (ImageView)view.findViewById(R.id.photo);
        photoImageView.setImageResource(R.drawable.ic_food_none);

        selectDialog = new Dialog(this, R.style.transparentFrameWindowStyle);
        selectDialog.setContentView(view, new LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT));
        Window window = selectDialog.getWindow();
        WindowManager windowManager = this.getWindowManager();
        // 设置显示动画
        WindowManager.LayoutParams wl = window.getAttributes();
        wl.x = 0;
        wl.y = 0;
        // 设置显示位置
        selectDialog.onWindowAttributesChanged(wl);

        Display display = windowManager.getDefaultDisplay();
        WindowManager.LayoutParams lp = window.getAttributes();
        lp.width = (int)(display.getWidth()*0.8); //设置宽度
        selectDialog.getWindow().setAttributes(lp);

        // 设置点击外围关闭
        selectDialog.setCanceledOnTouchOutside(true);
        selectDialog.show();

    }

    private void addToCartAnimation(final ImageView ball, boolean isDialog) {
        animLayout = null;
        animLayout = createAnimLayout(isDialog);

        final View view = addViewToAnimLayout(animLayout, ball, foodAddLocation);

        cart.getLocationInWindow(cartLocation);
        // 计算位移
        int endX = 0 - foodAddLocation[0] + cart.getWidth();
        int endY = cartLocation[1] - foodAddLocation[1] - cart.getHeight()*3;

        TranslateAnimation translateAnimationX = new TranslateAnimation(-cart.getHeight(),
                endX+cart.getHeight(), 0, 0);
        translateAnimationX.setInterpolator(new LinearInterpolator());
        translateAnimationX.setRepeatCount(0);
        translateAnimationX.setFillAfter(true);

        TranslateAnimation translateAnimationY = new TranslateAnimation(0, 0,
                -cart.getHeight()*3, endY-cart.getHeight());
        translateAnimationY.setInterpolator(new AccelerateInterpolator());
        translateAnimationY.setRepeatCount(0);
        translateAnimationY.setFillAfter(true);

        AnimationSet set = new AnimationSet(false);
        set.setFillAfter(false);
        set.addAnimation(translateAnimationY);
        set.addAnimation(translateAnimationX);
        set.setDuration(300);
        view.startAnimation(set);

        set.setAnimationListener(new AnimationListener() {
            @Override
            public void onAnimationStart(Animation animation) {
                ball.setVisibility(View.VISIBLE);
            }

            @Override
            public void onAnimationRepeat(Animation animation) {

            }

            @Override
            public void onAnimationEnd(Animation animation) {
                ball.setVisibility(View.GONE);
            }
        });

    }

    private ViewGroup createAnimLayout(boolean isDialog) {
        Window window;
        if(isDialog){
            window = selectDialog.getWindow();
        }else{
            window = this.getWindow();
        }
        ViewGroup rootView = (ViewGroup) window.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;
    }

    private View addViewToAnimLayout(final ViewGroup animLayout, final View ball,
            int[] foodAddLocation) {
        int x = foodAddLocation[0];
        int y = foodAddLocation[1];
        LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
                LinearLayout.LayoutParams.WRAP_CONTENT,
                LinearLayout.LayoutParams.WRAP_CONTENT);
        lp.leftMargin = x;
        lp.topMargin = y;
        ball.setLayoutParams(lp);
        animLayout.addView(ball);
        return ball;
    }

    @Override
    public void onClick(View v) {
        switch(v.getId()){
        case R.id.bt:
            showSelectDialog();
            break;
        case R.id.add:
            add.getLocationInWindow(foodAddLocation);
            ImageView ball = new ImageView(this);
            ball.setImageResource(R.drawable.badge_ifaux);
            addToCartAnimation(ball, true);
            break;
        default:
            break;
        }
    }

}

Answer 1

createAnimLayout(boolean isDialog)方法中用window = selectDialog.getWindow();时，动画只在Dialog的范围内，用window = this.getWindow();时，动画在Dialog的后面