Android实现水波纹外扩效果的实例代码

2019-10-22 18:11:09

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微信曾经推出了一个查找附近好友的功能，大致功能是这样的：屏幕上有一个按钮，长按按钮的时候，会有一圈圈水波纹的动画向外扩散，松手后，动画结束。

现在简单来实现这样的一个动画功能：

思路: 主要用到了下面的蓝色的图片，定义三个ImageView，background都设置为蓝色的图片，然后定义一个包括缩放和透明度变化的动画集，然后每隔一段时间，让3个ImageView依次启动这个动画集，看起来就像蓝色的圆圈像水波纹向外扩散一样。

android,水波纹,代码

相关实现逻辑如下：

activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  android:layout_width="match_parent"  android:layout_height="match_parent" >  <ImageView  android:id="@+id/wave1"  android:layout_width="150dp"  android:layout_height="150dp"  android:layout_centerInParent="true"  android:background="@drawable/wave"  />  <ImageView  android:id="@+id/wave2"  android:layout_width="150dp"  android:layout_height="150dp"  android:layout_centerInParent="true"  android:background="@drawable/wave"/>  <ImageView  android:id="@+id/wave3"  android:layout_width="150dp"  android:layout_height="150dp"  android:layout_centerInParent="true"  android:background="@drawable/wave" />  <ImageView  android:id="@+id/normal"  android:layout_width="166dp"  android:layout_height="166dp"  android:layout_centerInParent="true"  android:background="@drawable/normal" /> </RelativeLayout>

MainActivity.java

package com.jackie.waveanimation; import android.app.Activity; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.view.MotionEvent; import android.view.View; import android.view.animation.AlphaAnimation; import android.view.animation.AnimationSet; import android.view.animation.ScaleAnimation; import android.widget.ImageView; public class MainActivity extends Activity {  private ImageView mNormal, mWave1, mWave2, mWave3;  private AnimationSet mAnimationSet1, mAnimationSet2, mAnimationSet3;  private static final int OFFSET = 600; //每个动画的播放时间间隔  private static final int MSG_WAVE2_ANIMATION = 2;  private static final int MSG_WAVE3_ANIMATION = 3;  private Handler mHandler = new Handler() {  @Override  public void handleMessage(Message msg) {  switch (msg.what) {  case MSG_WAVE2_ANIMATION:  mWave2.startAnimation(mAnimationSet2);  break;  case MSG_WAVE3_ANIMATION:  mWave3.startAnimation(mAnimationSet3);  break;  }  }  };  @Override  protected void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.activity_main);  mNormal = (ImageView) findViewById(R.id.normal);  mWave1 = (ImageView) findViewById(R.id.wave1);  mWave2 = (ImageView) findViewById(R.id.wave2);  mWave3 = (ImageView) findViewById(R.id.wave3);  mAnimationSet1 = initAnimationSet();  mAnimationSet2 = initAnimationSet();  mAnimationSet3 = initAnimationSet();  mNormal.setOnTouchListener(new View.OnTouchListener() {  @Override  public boolean onTouch(View v, MotionEvent event) {  switch (event.getAction()) {  case MotionEvent.ACTION_DOWN:  showWaveAnimation();  break;  case MotionEvent.ACTION_UP:  clearWaveAnimation();  break;  case MotionEvent.ACTION_CANCEL:  clearWaveAnimation();  }  return true;  }  });  }  private AnimationSet initAnimationSet() {  AnimationSet as = new AnimationSet(true);  ScaleAnimation sa = new ScaleAnimation(1f, 2.3f, 1f, 2.3f,  ScaleAnimation.RELATIVE_TO_SELF, 0.5f,  ScaleAnimation.RELATIVE_TO_SELF, 0.5f);  sa.setDuration(OFFSET * 3);  sa.setRepeatCount(Animation.INFINITE);// 设置循环  AlphaAnimation aa = new AlphaAnimation(1, 0.1f);  aa.setDuration(OFFSET * 3);  aa.setRepeatCount(Animation.INFINITE);//设置循环  as.addAnimation(sa);  as.addAnimation(aa);  return as;  }  private void showWaveAnimation() {  mWave1.startAnimation(mAnimationSet1);  mHandler.sendEmptyMessageDelayed(MSG_WAVE2_ANIMATION, OFFSET);  mHandler.sendEmptyMessageDelayed(MSG_WAVE3_ANIMATION, OFFSET * 2);  }  private void clearWaveAnimation() {  mWave1.clearAnimation();  mWave2.clearAnimation();  mWave3.clearAnimation();  } }

效果如下：

android,水波纹,代码