揭露动画实现时的注意事项（附上bug-logcat）

Debug完成图：

Debug完成图

昨天晚上开始学一下这个揭露动画，准备用在项目中做一个转场，啃完了API之后开始写个小demo，距离跑成功一步之遥的当儿，出了个bug，就怎么点击按钮都没用。

首先上bug图：

bug：怎么点击按钮都没用，每点击一次都会出现下面的报错（2040）：

11-07 19:20:49.665 2454-2454/? I/Finsky: [1] com.google.android.finsky.services.j.a(149): Installation state replication succeeded.
11-07 19:20:49.711 7448-7448/? E/hei: 2040
11-07 19:20:49.718 1350-1371/? W/audio_hw_generic: Not supplying enough data to HAL, expected position 5613338 , only wrote 5613120
11-07 19:20:50.376 7448-7448/? E/hei: 2040
11-07 19:20:50.992 7448-7448/? E/hei: 2040
11-07 19:20:51.591 7448-7448/? E/hei: 2040
11-07 19:20:54.790 1350-1372/? W/audio_hw_generic: Not supplying enough data to HAL, expected position 6098164 , only wrote 5856480
11-07 19:20:58.322 7448-7448/? E/hei: 2040
11-07 19:20:58.328 1350-1371/? W/audio_hw_generic: Not supplying enough data to HAL, expected position 5856667 , only wrote 5856480
11-07 19:21:01.540 1350-1372/? W/audio_hw_generic: Not supplying enough data to HAL, expected position 6162708 , only wrote 6010560

activity.java全文：

package com.lwp.justtest;import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.support.design.widget.FloatingActionButton;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.ViewAnimationUtils;public class MainActivity extends AppCompatActivity implements View.OnClickListener {boolean flag = false;FloatingActionButton fab;private View mPuppet;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);mPuppet = findViewById(R.id.view_puppet);fab = (FloatingActionButton)findViewById(R.id.fab);fab.setOnClickListener(this);}@Overridepublic void onClick(View v) {doRevealAnimation();}private void doRevealAnimation() {int[] vLocation = new int[2];fab.getLocationInWindow(vLocation);int centerX = vLocation[0] + fab.getMeasuredWidth() / 2;int centerY = vLocation[1] + fab.getMeasuredHeight() / 2;int height = mPuppet.getHeight();int width = mPuppet.getWidth();int maxRradius = (int) Math.hypot(height, width);Log.e("hei", maxRradius + "");if (flag) {Animator animator = ViewAnimationUtils.createCircularReveal(mPuppet, centerX, centerY, maxRradius, 0);animator.setDuration(1000);animator.addListener(new AnimatorListenerAdapter() {@Overridepublic void onAnimationEnd(Animator animation) {super.onAnimationEnd(animation);mPuppet.setVisibility(View.GONE);}});animator.start();flag = false;} else {Animator animator = ViewAnimationUtils.createCircularReveal(mPuppet, centerX, centerY, 0, maxRradius);animator.setDuration(1000);animator.addListener(new Animator.AnimatorListener() {@Overridepublic void onAnimationStart(Animator animation) {mPuppet.setVisibility(View.VISIBLE);}@Overridepublic void onAnimationEnd(Animator animation) {}@Overridepublic void onAnimationCancel(Animator animation) {}@Overridepublic void onAnimationRepeat(Animator animation) {}});animator.start();flag = true;}}}

layout.xml全文：

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"xmlns:app="http://schemas.android.com/apk/res-auto"xmlns:tools="http://schemas.android.com/tools"android:layout_width="match_parent"android:layout_height="match_parent"tools:context="com.lwp.justtest.MainActivity"><TextViewandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:text="Hello World!"android:layout_gravity="center"app:layout_constraintBottom_toBottomOf="parent"app:layout_constraintLeft_toLeftOf="parent"app:layout_constraintRight_toRightOf="parent"app:layout_constraintTop_toTopOf="parent" /><Viewandroid:id="@+id/view_puppet"android:layout_width="match_parent"android:layout_height="match_parent"/><android.support.design.widget.FloatingActionButtonandroid:id="@+id/fab"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_gravity="bottom|end"android:layout_margin="16dp"android:backgroundTint="@color/colorPrimary"android:src="@drawable/map"app:pressedTranslationZ="10dp" /></FrameLayout>

观众朋友们，这个看出毛病了吗。

我想了一下，额，会不会我的View没有设置颜色啊。。好的试了一下，果然是，可以说是很鬼畜了。。

layout.xml里边的View控件改成下面这样子，再次运行程序就成了（发现2040还是会报错，但是动画算是完美跑出来了，所以小伙伴们这里记得设置android:background以及android:visibility噢）：

    <Viewandroid:id="@+id/view_puppet"android:background="@color/colorPrimaryDark"android:layout_width="match_parent"android:layout_height="match_parent"android:visibility="gone"/>

效果图如下：