Android动画：如果条件不满足，如何随着手指平滑移动视图并移动到其初始位置答案

【问题标题】：Android Animation: How to move a view smoothly along with finger and move to its initial position if condition is not satisfiedAndroid动画：如果条件不满足，如何随着手指平滑移动视图并移动到其初始位置
【发布时间】：2017-04-12 11:16:35
【问题描述】：

我想随着手指的移动平滑地移动视图，然后我想检查移动的距离，如果移动的距离小于预期的距离，那么我必须将视图移回其初始位置。

我已经搜索了很多，我已经到达了下面的代码，但这并没有按预期工作，当我触摸它时会显示两个视图并且不根据我的手指移动随意移动。

myView.setOnTouchListener(new View.OnTouchListener() {
 @Override
 public boolean onTouch(View view, MotionEvent motionEvent) {
 float dX = 0, dY = 0;
 originalX = myView.getX();
 originalY = myView.getY();
switch (motionEvent.getAction()) {
case MotionEvent.ACTION_DOWN:
 x1 = motionEvent.getX();
 break;
case MotionEvent.ACTION_UP:
x2 = motionEvent.getX();
float deltaX = x2 - x1;
if (Math.abs(deltaX) > MIN_DISTANCE) {
 myView.animate()
       .alpha(0.0f)
       .x(motionEvent.getRawX())
       .y(motionEvent.getRawY())
       .setDuration(500)
       .setListener(new Animator.AnimatorListener() {
 @Override
 public void onAnimationStart(Animator animator) {
}
@Override
public void onAnimationEnd(Animator animator) {
 myView.setVisibility(View.GONE);
 }
@Override
public void onAnimationCancel(Animator animator) {
 }
 @Override
public void onAnimationRepeat(Animator animator) {
 }
})
.start();
}else {
myView.setX(originalX);
myView.setY(originalY);
}
break;
 case MotionEvent.ACTION_MOVE:
myView.setX(motionEvent.getX());
myView.setY(motionEvent.getY());
break;
 }
return true;
 }
    });

请帮助我如何才能正确。

【问题讨论】：

标签： android animation android-animation android-touch-event

【解决方案1】：

如果您仍然遇到问题，请尝试以下代码：

private int _xDelta;
private int _yDelta;
 myView.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View view, MotionEvent motionEvent) {
            float dX = 0, dY = 0;
            final int X = (int) motionEvent.getRawX();
            final int Y = (int) motionEvent.getRawY();
            switch (motionEvent.getAction()) {
                case MotionEvent.ACTION_DOWN:
                    RelativeLayout.LayoutParams lParams = (RelativeLayout.LayoutParams) view.getLayoutParams();//Replace the RelativeLayout with your myView parent layout
                    x1 = myView.getX();
                    _xDelta = X - lParams.leftMargin;
                    _yDelta = Y - lParams.topMargin;
                    originalX = myView.getX();
                    originalY = myView.getY();
                    break;
                case MotionEvent.ACTION_UP:
                    x2 = myView.getX();
                    float deltaX = x2 - x1;
                    if (Math.abs(deltaX) > MIN_DISTANCE) {
                        myView.animate()
                                .alpha(0.0f)
                                .x(motionEvent.getRawX())
                                .y(motionEvent.getRawY())
                                .setDuration(500)
                                .setListener(new Animator.AnimatorListener() {
                                    @Override
                                    public void onAnimationStart(Animator animator) {
                                    }
                                    @Override
                                    public void onAnimationEnd(Animator animator) {
                                        myView.setVisibility(View.GONE);
                                    }
                                    @Override
                                    public void onAnimationCancel(Animator animator) {
                                    }
                                    @Override
                                    public void onAnimationRepeat(Animator animator) {
                                    }
                                })
                                .start();
                    }else {
                        myView.setX(originalX);
                        myView.setY(originalY);
                    }
                    break;
                case MotionEvent.ACTION_MOVE:
                    RelativeLayout.LayoutParams layoutParams = (RelativeLayout.LayoutParams) view.getLayoutParams();//Replace the RelativeLayout with your myView parent layout
                    layoutParams.leftMargin = X - _xDelta;
                    layoutParams.topMargin = Y - _yDelta;
                    view.setLayoutParams(layoutParams);
                    break;
            }
            return true;
        }
    });

【讨论】：