Android基於ImageSwitcher實現圖片切換功能

左右切換圖片控件大家都用ViewPager, ViewFipper比較多吧，我之前也用ViewPager實現了，使用ViewPager實現左右循環滑動圖片，有興趣的可以去看下，今天介紹的是基於ImageSwitcher實現的左右切換圖片，先上截圖吧

好了，接下來來看代碼吧，第一張圖是一個GridView，點擊item跳轉到第二個界面，第一個界面可以忽略，主要是講解ImageSwitcher的左右卻換圖片，先看布局文件

<?xml version="1.0" encoding="UTF-8"?> 
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android" 
  android:layout_width="fill_parent" 
  android:layout_height="fill_parent" > 
  <ImageSwitcher 
    android:id="@+id/imageSwitcher1" 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent"> 
  </ImageSwitcher> 
   
  <RelativeLayout   
    android:layout_width="fill_parent"   
    android:layout_height="wrap_content"   
    android:orientation="vertical" >   
    <LinearLayout   
      android:id="@+id/viewGroup"   
      android:layout_width="fill_parent"   
      android:layout_height="wrap_content"   
      android:layout_alignParentBottom="true"   
      android:layout_marginBottom="30dp"   
      android:gravity="center_horizontal"   
      android:orientation="horizontal" >   
    </LinearLayout>   
  </RelativeLayout> 
</FrameLayout> 

然後就是Activity代碼啦，總體來說比較簡單，代碼我添加了注釋

package com.example.photoalbum; 
 
import android.app.Activity; 
import android.os.Bundle; 
import android.view.MotionEvent; 
import android.view.View; 
import android.view.View.OnTouchListener; 
import android.view.ViewGroup; 
import android.view.animation.AnimationUtils; 
import android.widget.ImageSwitcher; 
import android.widget.ImageView; 
import android.widget.LinearLayout; 
import android.widget.RelativeLayout.LayoutParams; 
import android.widget.Toast; 
import android.widget.ViewSwitcher.ViewFactory; 
 
public class ShowPhotoActivity extends Activity implements ViewFactory, OnTouchListener{ 
  /** 
   * ImagaSwitcher 的引用 
   */ 
  private ImageSwitcher mImageSwitcher; 
  /** 
   * 圖片id數組 
   */ 
  private int[] imgIds; 
  /** 
   * 當前選中的圖片id序號 
   */ 
  private int currentPosition; 
  /** 
   * 按下點的X坐標 
   */ 
  private float downX; 
  /** 
   * 裝載點點的容器 
   */ 
  private LinearLayout linearLayout; 
  /** 
   * 點點數組 
   */ 
  private ImageView[] tips; 
  
  @Override 
  protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.show_photo); 
     
    imgIds = new int[]{R.drawable.item01,R.drawable.item02,R.drawable.item03,R.drawable.item04, 
        R.drawable.item05, R.drawable.item06, R.drawable.item07, R.drawable.item08,R.drawable.item09, 
        R.drawable.item10, R.drawable.item11, R.drawable.item12}; 
    //實例化ImageSwitcher 
    mImageSwitcher = (ImageSwitcher) findViewById(R.id.imageSwitcher1); 
    //設置Factory 
    mImageSwitcher.setFactory(this); 
    //設置OnTouchListener，我們通過Touch事件來切換圖片 
    mImageSwitcher.setOnTouchListener(this); 
     
    linearLayout = (LinearLayout) findViewById(R.id.viewGroup); 
     
    tips = new ImageView[imgIds.length]; 
    for(int i=0; i<imgIds.length; i++){ 
      ImageView mImageView = new ImageView(this); 
      tips[i] = mImageView; 
      LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(new ViewGroup.LayoutParams(LayoutParams.WRAP_CONTENT,   
          LayoutParams.WRAP_CONTENT));  
      layoutParams.rightMargin = 3; 
      layoutParams.leftMargin = 3; 
       
      mImageView.setBackgroundResource(R.drawable.page_indicator_unfocused); 
      linearLayout.addView(mImageView, layoutParams); 
    } 
     
    //這個我是從上一個界面傳過來的，上一個界面是一個GridView 
    currentPosition = getIntent().getIntExtra("position", 0); 
    mImageSwitcher.setImageResource(imgIds[currentPosition]); 
     
    setImageBackground(currentPosition); 
     
  } 
   
   /** 
   * 設置選中的tip的背景 
   * @param selectItems 
   */  
  private void setImageBackground(int selectItems){  
    for(int i=0; i<tips.length; i++){  
      if(i == selectItems){  
        tips[i].setBackgroundResource(R.drawable.page_indicator_focused);  
      }else{  
        tips[i].setBackgroundResource(R.drawable.page_indicator_unfocused);  
      }  
    }  
  }  
 
  @Override 
  public View makeView() { 
    final ImageView i = new ImageView(this); 
    i.setBackgroundColor(0xff000000); 
    i.setScaleType(ImageView.ScaleType.CENTER_CROP); 
    i.setLayoutParams(new ImageSwitcher.LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT)); 
    return i ; 
  } 
 
  @Override 
  public boolean onTouch(View v, MotionEvent event) { 
    switch (event.getAction()) { 
    case MotionEvent.ACTION_DOWN:{ 
      //手指按下的X坐標 
      downX = event.getX(); 
      break; 
    } 
    case MotionEvent.ACTION_UP:{ 
      float lastX = event.getX(); 
      //抬起的時候的X坐標大於按下的時候就顯示上一張圖片 
      if(lastX > downX){ 
        if(currentPosition > 0){ 
          //設置動畫，這裡的動畫比較簡單，不明白的去網上看看相關內容 
          mImageSwitcher.setInAnimation(AnimationUtils.loadAnimation(getApplication(), R.anim.left_in)); 
          mImageSwitcher.setOutAnimation(AnimationUtils.loadAnimation(getApplication(), R.anim.right_out)); 
          currentPosition --; 
          mImageSwitcher.setImageResource(imgIds[currentPosition % imgIds.length]); 
          setImageBackground(currentPosition); 
        }else{ 
          Toast.makeText(getApplication(), "已經是第一張", Toast.LENGTH_SHORT).show(); 
        } 
      }  
       
      if(lastX < downX){ 
        if(currentPosition < imgIds.length - 1){ 
          mImageSwitcher.setInAnimation(AnimationUtils.loadAnimation(getApplication(), R.anim.right_in)); 
          mImageSwitcher.setOutAnimation(AnimationUtils.loadAnimation(getApplication(), R.anim.lift_out)); 
          currentPosition ++ ; 
          mImageSwitcher.setImageResource(imgIds[currentPosition]); 
          setImageBackground(currentPosition); 
        }else{ 
          Toast.makeText(getApplication(), "到了最後一張", Toast.LENGTH_SHORT).show(); 
        } 
      } 
      } 
       
      break; 
    } 
 
    return true; 
  } 
 
} 

上面切換圖片主要用到的就是動畫了，用的是translate移動動畫，這裡我就不介紹了，接下來我吧動畫代碼貼出來，在res新建一個anim的目錄，如下圖

左邊進入的動畫，left_in.xml

<?xml version="1.0" encoding="UTF-8"?> 
<set xmlns:android="http://schemas.android.com/apk/res/android"> 
  <translate  
    android:fromXDelta="-100%p" 
    android:toXDelta="0" 
    android:duration="500"/> 
</set> 

左邊出去的動畫,left_out.xml

<?xml version="1.0" encoding="UTF-8"?> 
<set xmlns:android="http://schemas.android.com/apk/res/android"> 
  <translate  
    android:fromXDelta="0" 
    android:toXDelta="-100%p" 
    android:duration="500"/> 
</set> 

右邊進入的動畫，right_in.xml

<?xml version="1.0" encoding="UTF-8"?> 
<set xmlns:android="http://schemas.android.com/apk/res/android"> 
  <translate  
    android:fromXDelta="100%p" 
    android:toXDelta="0" 
    android:duration="500"/> 
</set> 

右邊出去的動畫,right_out.xml

<?xml version="1.0" encoding="UTF-8"?> 
<set xmlns:android="http://schemas.android.com/apk/res/android"> 
  <translate  
    android:fromXDelta="0" 
    android:toXDelta="100%p" 
    android:duration="500"/> 
</set> 

好了，介紹完了，代碼寫的不是很好，寫的不好的地方希望大家諒解，小編一定更加努力。