[android]仿制新浪微博消息页面 图标切换动画

研究了下以前不怎么用到的动画效果的实现 

顺便做了一个新浪微博消息页面 图标切换动画 效果的实例

 

如图

然后封装了一下这个效果的实现代码

 

如下

 

 package com.lurencun.unit.unit;

 import android.app.Activity;
 import android.graphics.BitmapFactory;
 import android.graphics.Matrix;
 import android.view.animation.Animation;
 import android.view.animation.TranslateAnimation;
 import android.widget.ImageView;

 /**
  * 标签切换对应动画效果实现类
  *
  * @author poolo
  * @since 2012年8月10日
  * @version 1.0.0 完成了2,3,4个标签的情况下的处理(越多- -就要以笛卡尔积的数量增长- -我觉得呢2~4够用了)
  */
 public class Unit {
     private int current = 0;
     private Activity at;
     private ImageView cursor;
     private float bmpW;
     private float screenW;
     private float offset;// 偏移量

     /**
      *
      * @param a
      *            当前Activity
      * @param layoutId
      *            当前作为图标使用的ImageViewId
      * @param drawId
      *            当前图标的drawId
      * @param num
      *            当前标签个数
      */
     public Unit(Activity a, int viewId, int drawId, int num) {
         at = a;
         init(viewId, drawId, num);
     }

     /**
      * 纯粹是为了好看些的一个初始化数据包 无视这里吧
      *
      * @param viewId
      * @param drawId
      * @param num
      */
     private void init(int viewId, int drawId, int num) {
         cursor = (ImageView) at.findViewById(viewId);
         bmpW = BitmapFactory.decodeResource(at.getResources(), drawId)
                 .getWidth();
         screenW = at.getWindowManager().getDefaultDisplay().getWidth();
         offset = (screenW / num - bmpW) / 2;
         Matrix matrix = new Matrix();
         matrix.postTranslate(offset, 0);
         cursor.setImageMatrix(matrix);
     }

     /**
      * 两个标签的情况
      * @param selectId 被选中的id
      */
     public void move2tag(int selectId) {
         Animation animation = null;
         float zero = 0;
         float one = offset * 2 + bmpW;
         switch (selectId) {
         case 0:
             if (current == 1) {
                 animation = new TranslateAnimation(one, zero, 0, 0);
             }
             break;
         case 1:
             if (current == 0) {
                 animation = new TranslateAnimation(zero, one, 0, 0);
             }
             break;
         }
         current = selectId;
         animation.setFillAfter(true);
         animation.setDuration(300);
         cursor.startAnimation(animation);
     }

     /**
      * 三个标签的情况
      * @param selectId 被选中的id
      */
     public void move3tag(int selectId) {
         Animation animation = null;
         float zero = 0;
         float one = offset * 2 + bmpW;
         float two = one * 2;
         switch (selectId) {
         case 0:
             if (current == 1) {
                 animation = new TranslateAnimation(one, zero, 0, 0);
             }
             if (current == 2) {
                 animation = new TranslateAnimation(two, zero, 0, 0);
             }
             break;
         case 1:
             if (current == 0) {
                 animation = new TranslateAnimation(zero, one, 0, 0);
             }
             if (current == 2) {
                 animation = new TranslateAnimation(two, one, 0, 0);
             }
             break;

         case 2:
             if (current == 0) {
                 animation = new TranslateAnimation(zero, two, 0, 0);
             }
             if (current == 1) {
                 animation = new TranslateAnimation(one, two, 0, 0);
                 break;
             }
         }
         current = selectId;
         animation.setFillAfter(true);
         animation.setDuration(300);
         cursor.startAnimation(animation);
     }

     /**
      * 四个标签的情况
      * @param selectId 被选中的id
      */
     public void move4tag(int selectId) {
         Animation animation = null;
         float zero = 0;
         float one = offset * 2 + bmpW;
         float two = one * 2;
         float three = one * 3;
         switch (selectId) {
         case 0:
             if (current == 1) {
                 animation = new TranslateAnimation(one, zero, 0, 0);
             }
             if (current == 2) {
                 animation = new TranslateAnimation(two, zero, 0, 0);
             }
             if (current == 3) {
                 animation = new TranslateAnimation(three, zero, 0, 0);
             }
             break;
         case 1:
             if (current == 0) {
                 animation = new TranslateAnimation(zero, one, 0, 0);
             }
             if (current == 2) {
                 animation = new TranslateAnimation(two, one, 0, 0);
             }
             if (current == 3) {
                 animation = new TranslateAnimation(three, one, 0, 0);
             }
             break;

         case 2:
             if (current == 0) {
                 animation = new TranslateAnimation(zero, two, 0, 0);
             }
             if (current == 1) {
                 animation = new TranslateAnimation(one, two, 0, 0);

             }
             if (current == 3) {
                 animation = new TranslateAnimation(three, two, 0, 0);
             }
             break;
         case 3:
             if (current == 0) {
                 animation = new TranslateAnimation(zero, three, 0, 0);
             }
             if (current == 1) {
                 animation = new TranslateAnimation(one, three, 0, 0);

             }
             if (current == 2) {
                 animation = new TranslateAnimation(two, three, 0, 0);
             }
             break;
         }
         current = selectId;
         animation.setFillAfter(true);
         animation.setDuration(300);
         cursor.startAnimation(animation);
     }
 }

 

 

 一个需要注意的地方 使用此方法的童鞋 切记自己的ImageView需要设置 android:scaleType="matrix" 才能使图形作为矩形计算 不至于出现错误

 

 <ImageView
     android:id="@+id/testImg1"
     android:layout_width="fill_parent"
     android:layout_height="wrap_content"
     android:contentDescription="@string/hello"
     android:scaleType="matrix"
     android:src="@drawable/jian_tou" />

 

 

部分借鉴与：http://www.eoeandroid.com/code/2012/0322/994_2.html

 

另如果路过的同学知道如何截android手机上的动态图麻烦留言告知下，谢谢。

 

jar包,源码,apk,截图都在下面。

 

 

已经交给团队封装代码的童鞋 将会封装到这个工具jar中

https://github.com/chenyoca/ToolkitForAndroid