Android使用CircularReveal动画让页面跳转更炫酷

/* @param view The View will be clipped to the animating circle.
   * @param centerX The x coordinate of the center of the animating circle, relative to
   *        view.
   * @param centerY The y coordinate of the center of the animating circle, relative to
   *        view.
   * @param startRadius The starting radius of the animating circle.
   * @param endRadius The ending radius of the animating circle.
   */
  public static Animator createCircularReveal(View view,
      int centerX, int centerY, float startRadius, float endRadius) {
    return new RevealAnimator(view, centerX, centerY, startRadius, endRadius);
  }

@SuppressLint("NewApi")
  private fun actionOtherVisible(isShow: Boolean, triggerView: View, animView: View) {
    //判断API是否大于21
    if (android.os.Build.VERSION.SDK_INT < android.os.Build.VERSION_CODES.LOLLIPOP) {
      if (isShow) {
        animView.visibility = View.VISIBLE
        if (mListener != null) mListener!!.onShowAnimationEnd()
      } else {
        animView.visibility = View.GONE
        if (mListener != null) mListener!!.onHideAnimationEnd()
      }
      return
    }

    /**
     * 计算 triggerView(即搜索按钮) 的中心位置
     */
    val tvLocation = IntArray(2)
    triggerView.getLocationInWindow(tvLocation)
    val tvX = tvLocation[0] + triggerView.width / 2
    val tvY = tvLocation[1] + triggerView.height / 2

    /**
     * 计算 animView(即根布局) 的中心位置
     */
    val avLocation = IntArray(2)
    animView.getLocationInWindow(avLocation)
    val avX = avLocation[0] + animView.width / 2
    val avY = avLocation[1] + animView.height / 2
    //计算宽高
    val rippleW = if (tvX < avX) animView.width - tvX else tvX - avLocation[0]
    val rippleH = if (tvY < avY) animView.height - tvY else tvY - avLocation[1]
    //勾股定理求斜边
    val maxRadius = Math.sqrt((rippleW * rippleW + rippleH * rippleH).toDouble()).toFloat()
    val startRadius: Float
    val endRadius: Float
    //根据展示或隐藏设置起始与结束的半径
    if (isShow) {
      startRadius = 0f
      endRadius = maxRadius
    } else {
      startRadius = maxRadius
      endRadius = 0f
    }

    val anim = ViewAnimationUtils.createCircularReveal(animView, tvX, tvY, startRadius, endRadius)
    animView.visibility = View.VISIBLE
    anim.duration = DURATION
    anim.interpolator = DecelerateInterpolator()
    //监听动画结束，进行回调
    anim.addListener(object : AnimatorListenerAdapter() {
      override fun onAnimationEnd(animation: Animator) {
        super.onAnimationEnd(animation)
        if (isShow) {
          animView.visibility = View.VISIBLE
          if (mListener != null) mListener!!.onShowAnimationEnd()
        } else {
          animView.visibility = View.GONE
          if (mListener != null) mListener!!.onHideAnimationEnd()
        }
      }
    })

    anim.start()
  }

fun show(triggerView: View, showView: View) {
    actionOtherVisible(true, triggerView, showView)
  }

fun hide(triggerView: View, hideView: View) {
    actionOtherVisible(false, triggerView, hideView)
  }

override fun onPreDraw(): Boolean {
    iv_search_search.viewTreeObserver.removeOnPreDrawListener(this);
    mCircularRevealAnim.show(iv_search_search, mRootView);
    return true;
  }

override fun onHideAnimationEnd() {
  et_search_keyword.setText("");
  dismiss();
}

override fun onShowAnimationEnd() {
  if (isVisible) {
    KeyBoardUtils.openKeyboard(activity, et_search_keyword);
  }
}