做一个商品加入购物车的效果，之前一直想尝试去实现，无奈啊，没机会。致谢

怎么用？

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public void addAction(View view) { new DriftingTextView(this) .startView(view) .rootView(getWindow().getDecorView()) .endView(btCart) .startBesselAnim(); } </pre>

代码很少

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package github.alex.jumpview; import android.animation.Animator; import android.animation.AnimatorListenerAdapter; import android.animation.TypeEvaluator; import android.animation.ValueAnimator; import android.content.Context; import android.graphics.Color; import android.graphics.Point; import android.graphics.drawable.GradientDrawable; import android.os.Build; import android.util.AttributeSet; import android.util.TypedValue; import android.view.Gravity; import android.view.View; import android.view.ViewGroup; import android.view.animation.AccelerateDecelerateInterpolator; import android.widget.TextView;

/**

* 漂移的文本控件 * 作者：alex * 时间：2016/7/28 10:54 * 博客地址： */ public class DriftingTextView extends TextView { private GradientDrawable gradientDrawable; private static final int VIEW_SIZE = 20;

/\*\* \* 控件的半径 \*/protected int radius;/\*\* \* 起点 \*/protected Point startPoint;/\*\* \* 终点 \*/protected Point endPoint;/\*\* \* 漂移的时间 \*/private long driftingDuration;public DriftingTextView(Context context) {    super(context);    initView();}public DriftingTextView(Context context, AttributeSet attrs) {    super(context, attrs);    initView();}private void initView() {    driftingDuration = 500;    gradientDrawable = new GradientDrawable();    gradientDrawable.setShape(GradientDrawable.OVAL);    gradientDrawable.setColor(Color.parseColor("#FF0000"));    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {        setBackground(gradientDrawable);    } else {        setBackgroundDrawable(gradientDrawable);    }    setGravity(Gravity.CENTER);    setText("1");    setTextColor(Color.WHITE);    setTextSize(10);}@Overrideprotected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {    int size = (int) dp2Px(VIEW_SIZE);    setMeasuredDimension(size, size);    radius = size / 2;}/\*\* \* 设置  起始点 \*/public DriftingTextView startPoint(Point startPoint) {    startPoint.y -= 10;    this.startPoint = startPoint;    return this;}/\*\* \* 设置 起始点的 控件 \*/public DriftingTextView startView(View view) {    int position[] = new int[2];    view.getLocationInWindow(position);    startPoint(new Point(position[0], position[1]));    return this;}/\*\* \* 设置 结束点 \*/public DriftingTextView endPoint(Point endPoint) {    this.endPoint = endPoint;    return this;}/\*\* \* 设置 结束点的 控件 \*/public DriftingTextView endView(View view) {    int position[] = new int[2];    view.getLocationInWindow(position);    endPoint(new Point(position[0], position[1]));    return this;}/\*\* \* 设置漂移文本控件的 父控件 \*/public DriftingTextView rootView(ViewGroup viewGroup) {    viewGroup.addView(this);    return this;}/\*\* \* 设置漂移文本控件的 父控件 \*/public DriftingTextView rootView(View view) {    if(view instanceof ViewGroup){        ViewGroup viewGroup = (ViewGroup) view;        viewGroup.addView(this);    }    return this;}/\*\* \* 设置 漂移时间 \* \* @param driftingDuration 漂移时间，单位 ms \*                         如果小于 20ms，或者大于 5000ms，使用默认时间500ms \*/public DriftingTextView driftingDuration(long driftingDuration) {    if ((driftingDuration < 20) || (driftingDuration > 5000)) {        driftingDuration = 500;    }    this.driftingDuration = driftingDuration;    return this;}public void startBesselAnim() {    if (startPoint == null || endPoint == null) return;    int pointX = (startPoint.x + endPoint.x) / 2;    int pointY = (int) (startPoint.y - dp2Px(100));    Point driftingPoint = new Point(pointX, pointY);    BesselEvaluator bezierEvaluator = new BesselEvaluator(driftingPoint);    ValueAnimator anim = ValueAnimator.ofObject(bezierEvaluator, startPoint, endPoint);    anim.addUpdateListener(new MyAnimatorUpdateListener());    anim.setDuration(driftingDuration);    anim.addListener(new MyAnimatorListenerAdapter());    anim.setInterpolator(new AccelerateDecelerateInterpolator());    anim.start();}private final class MyAnimatorListenerAdapter extends AnimatorListenerAdapter {    @Override    public void onAnimationEnd(Animator animation) {        super.onAnimationEnd(animation);        ViewGroup viewGroup = (ViewGroup) getParent();        viewGroup.removeView(DriftingTextView.this);    }}private final class MyAnimatorUpdateListener implements ValueAnimator.AnimatorUpdateListener {    @Override    public void onAnimationUpdate(ValueAnimator valueAnimator) {        Point point = (Point) valueAnimator.getAnimatedValue();        setX(point.x);        setY(point.y);        invalidate();    }}public class BesselEvaluator implements TypeEvaluator
     
       {    private Point driftingPoint;    public BesselEvaluator(Point driftingPoint) {        this.driftingPoint = driftingPoint;    }    @Override    public Point evaluate(float t, Point startValue, Point endValue) {        int x = (int) ((1 - t) \* (1 - t) \* startValue.x + 2 \* t \* (1 - t) \* driftingPoint.x + t \* t \* endValue.x);        int y = (int) ((1 - t) \* (1 - t) \* startValue.y + 2 \* t \* (1 - t) \* driftingPoint.y + t \* t \* endValue.y);        return new Point(x, y);    }}/\*\* \* 数据转换: dp---->px \*/private float dp2Px(float dp) {    return dp \* getContext().getResources().getDisplayMetrics().density;}/\*\* \* sp转px \*/private float sp2px(float sp) {    return TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, sp, getContext().getResources().getDisplayMetrics());}
     

}

public class BezierUtil {

/\*\* \* B(t) = (1 - t)^2 \* P0 + 2t \* (1 - t) \* P1 + t^2 \* P2, t ∈ [0,1] \* \* @param t  曲线长度比例 \* @param p0 起始点 \* @param p1 控制点 \* @param p2 终止点 \* @return t对应的点 \*/public static PointF CalculateBezierPointForQuadratic(float t, PointF p0, PointF p1, PointF p2) {    PointF point = new PointF();    float temp = 1 - t;    point.x = temp \* temp \* p0.x + 2 \* t \* temp \* p1.x + t \* t \* p2.x;    point.y = temp \* temp \* p0.y + 2 \* t \* temp \* p1.y + t \* t \* p2.y;    return point;}/\*\* \* B(t) = P0 \* (1-t)^3 + 3 \* P1 \* t \* (1-t)^2 + 3 \* P2 \* t^2 \* (1-t) + P3 \* t^3, t ∈ [0,1] \* \* @param t  曲线长度比例 \* @param p0 起始点 \* @param p1 控制点1 \* @param p2 控制点2 \* @param p3 终止点 \* @return t对应的点 \*/public static PointF CalculateBezierPointForCubic(float t, PointF p0, PointF p1, PointF p2, PointF p3) {    PointF point = new PointF();    float temp = 1 - t;    point.x = p0.x \* temp \* temp \* temp + 3 \* p1.x \* t \* temp \* temp + 3 \* p2.x \* t \* t \* temp + p3.x \* t \* t \* t;    point.y = p0.y \* temp \* temp \* temp + 3 \* p1.y \* t \* temp \* temp + 3 \* p2.y \* t \* t \* temp + p3.y \* t \* t \* t;    return point;}

}

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