• Android利用universal-image-loader异步加载大量图片完整示例


    MainActivity如下:

    package cc.testlistview;
    import java.util.ArrayList;
    import com.example.testlistview.R;
    import com.nostra13.universalimageloader.cache.disc.naming.Md5FileNameGenerator;
    import com.nostra13.universalimageloader.core.ImageLoader;
    import com.nostra13.universalimageloader.core.ImageLoaderConfiguration;
    import com.nostra13.universalimageloader.core.assist.QueueProcessingType;
    import android.os.Bundle;
    import android.app.Activity;
    import android.content.Context;
    import android.widget.ListView;
    /**
     * Demo描述:
     * 利用第三方工具universal-image-loader为ListView异步加载图片
     * 
     * 参考文档:
     * 1 http://blog.csdn.net/hkg1pek/article/details/9057815
     * 2 http://blog.csdn.net/wwj_748/article/details/10079311
     *   Thank you very much
     *
     */
    public class MainActivity extends Activity {
        private ListView mListView;
        private ImageLoader mImageLoader;
        private Context mContext;
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            initView();
            initImageLoader(this);
        }
        
      public void initView() {
        mContext=this;
        mImageLoader=ImageLoader.getInstance();
        mListView = (ListView) findViewById(R.id.listView);
        ArrayList<ListViewItem> arrayList = new ArrayList<ListViewItem>();
        String imagesUrl[] = ImagesUrl.Urls;
        ListViewItem listViewItem = null;
        for (int i = 0; i < imagesUrl.length; i++) {
          listViewItem = new ListViewItem("This is " + i, imagesUrl[i]);
          arrayList.add(listViewItem);
        }
    
        ListViewAdapter adapter = new ListViewAdapter(arrayList,mContext,mImageLoader);
        mListView.setAdapter(adapter);
      }
      
      
       /**
         *  Configuration of ImageLoader:
         *  This configuration tuning is custom.
         *  You can tune every option, you may tune some of them,
         *  or you can create default configuration by
         *  ImageLoaderConfiguration.createDefault(this) method.
         *  
         *  Note:
         *  1 enableLogging() // Not necessary in common
         *  2 实际项目中可将其放到Application中
         */
        public static void initImageLoader(Context context) {
        ImageLoaderConfiguration config = new ImageLoaderConfiguration
                          .Builder(context)
                              .threadPriority(Thread.NORM_PRIORITY - 2)
                          .denyCacheImageMultipleSizesInMemory()
                          .discCacheFileNameGenerator(new Md5FileNameGenerator())
                          .tasksProcessingOrder(QueueProcessingType.LIFO)
                          .enableLogging()
                          .build();
        ImageLoader.getInstance().init(config);
      }
      
      
      @Override
      protected void onDestroy() {
        super.onDestroy();
        if (mImageLoader!=null) {
          mImageLoader.clearMemoryCache();
          mImageLoader.clearDiscCache();
        }
      }
    }

    ListViewAdapter如下:

    package cc.testlistview;
    
    import java.util.ArrayList;
    import java.util.Collections;
    import java.util.LinkedList;
    import java.util.List;
    import android.content.Context;
    import android.graphics.Bitmap;
    import android.view.LayoutInflater;
    import android.view.View;
    import android.view.ViewGroup;
    import android.widget.BaseAdapter;
    import android.widget.ImageView;
    import android.widget.TextView;
    import com.example.testlistview.R;
    import com.nostra13.universalimageloader.core.DisplayImageOptions;
    import com.nostra13.universalimageloader.core.ImageLoader;
    import com.nostra13.universalimageloader.core.assist.SimpleImageLoadingListener;
    import com.nostra13.universalimageloader.core.display.FadeInBitmapDisplayer;
    
    public class ListViewAdapter extends BaseAdapter{
          private ArrayList<ListViewItem> mArrayList;
          private Context mContext;
          private ImageLoader mImageLoader;
          private DisplayImageOptions mDisplayImageOptions;
          private ImageLoadingListenerImpl mImageLoadingListenerImpl;
    
      public ListViewAdapter(ArrayList<ListViewItem> arrayList,Context context, ImageLoader imageLoader) {
        super();
        this.mArrayList = arrayList;
        this.mContext = context;
        this.mImageLoader = imageLoader;
        int defaultImageId = R.drawable.ic_launcher;
        mDisplayImageOptions = new DisplayImageOptions.Builder()
                           .showStubImage(defaultImageId)
                           .showImageForEmptyUri(defaultImageId)
                           .showImageOnFail(defaultImageId)
                           .cacheInMemory(true)
                           .cacheOnDisc(true)
                           .resetViewBeforeLoading()
                           .build();
        mImageLoadingListenerImpl=new ImageLoadingListenerImpl();
      }
    
      public int getCount() {
        if (mArrayList==null) {
          return 0;
        } else {
          return mArrayList.size();
        }
        
      }
    
      public Object getItem(int position) {
        if (mArrayList==null) {
          return null;
        } else {
                return mArrayList.get(position);
        }
      }
    
      public long getItemId(int position) {
        return position;
      }
    
      public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder=null;
        if (convertView==null) {
          holder=new ViewHolder();
          convertView=LayoutInflater.from(this.mContext).inflate(R.layout.listviewitem, null, false);
          holder.textView=(TextView) convertView.findViewById(R.id.textView);
            holder.imageView=(ImageView) convertView.findViewById(R.id.imageview);
            convertView.setTag(holder);
        } else {
                holder=(ViewHolder) convertView.getTag();
        }
        
      
        if (this.mArrayList!=null) {
          ListViewItem listViewItem=this.mArrayList.get(position);
          if (holder.textView!=null) {
            holder.textView.setText(listViewItem.getContent());
          }
          if (holder.imageView!=null) {
            try {
              //加载图片
              mImageLoader.displayImage(
                  listViewItem.imageURL, 
                  holder.imageView,
                  mDisplayImageOptions, 
                  mImageLoadingListenerImpl);
            } catch (Exception e) {
              e.printStackTrace();
            }
              
          }
        }	    
        return convertView;
      }
      
      //监听图片异步加载
      public static class ImageLoadingListenerImpl extends SimpleImageLoadingListener {
    
        public static final List<String> displayedImages = 
              Collections.synchronizedList(new LinkedList<String>());
    
        @Override
        public void onLoadingComplete(String imageUri, View view,Bitmap bitmap) {
          if (bitmap != null) {
            ImageView imageView = (ImageView) view;
            boolean isFirstDisplay = !displayedImages.contains(imageUri);
            if (isFirstDisplay) {
              //图片的淡入效果
              FadeInBitmapDisplayer.animate(imageView, 500);
              displayedImages.add(imageUri);
              System.out.println("===> loading "+imageUri);
            }
          }
        }
      }
    
      
      
      private class ViewHolder{
        ImageView imageView;
        TextView textView;
      }
          
    }

    ListViewItem如下:

    package cc.testlistview;
    public class ListViewItem {
      String content;
      String imageURL;
    
      public ListViewItem(String content, String imageURL) {
        super();
        this.content = content;
        this.imageURL = imageURL;
      }
    
      public String getContent() {
        return content;
      }
    
      public void setContent(String content) {
        this.content = content;
      }
    
      public String getImageURL() {
        return imageURL;
      }
    
      public void setImageURL(String imageURL) {
        this.imageURL = imageURL;
      }
    
    }

    ImagesUrl如下:

    package cc.testlistview;
    
    public class ImagesUrl {
    
      public final static String[] Urls = new String[] {
          "https://lh6.googleusercontent.com/-55osAWw3x0Q/URquUtcFr5I/AAAAAAAAAbs/rWlj1RUKrYI/s160-c/A%252520Photographer.jpg",
          "https://lh4.googleusercontent.com/--dq8niRp7W4/URquVgmXvgI/AAAAAAAAAbs/-gnuLQfNnBA/s160-c/A%252520Song%252520of%252520Ice%252520and%252520Fire.jpg",
          "https://lh5.googleusercontent.com/-7qZeDtRKFKc/URquWZT1gOI/AAAAAAAAAbs/hqWgteyNXsg/s160-c/Another%252520Rockaway%252520Sunset.jpg",
          "https://lh3.googleusercontent.com/--L0Km39l5J8/URquXHGcdNI/AAAAAAAAAbs/3ZrSJNrSomQ/s160-c/Antelope%252520Butte.jpg",
          "https://lh6.googleusercontent.com/-8HO-4vIFnlw/URquZnsFgtI/AAAAAAAAAbs/WT8jViTF7vw/s160-c/Antelope%252520Hallway.jpg",
          "https://lh4.googleusercontent.com/-WIuWgVcU3Qw/URqubRVcj4I/AAAAAAAAAbs/YvbwgGjwdIQ/s160-c/Antelope%252520Walls.jpg",
          "https://lh6.googleusercontent.com/-UBmLbPELvoQ/URqucCdv0kI/AAAAAAAAAbs/IdNhr2VQoQs/s160-c/Apre%2525CC%252580s%252520la%252520Pluie.jpg",
          "https://lh3.googleusercontent.com/-s-AFpvgSeew/URquc6dF-JI/AAAAAAAAAbs/Mt3xNGRUd68/s160-c/Backlit%252520Cloud.jpg",
          "https://lh5.googleusercontent.com/-bvmif9a9YOQ/URquea3heHI/AAAAAAAAAbs/rcr6wyeQtAo/s160-c/Bee%252520and%252520Flower.jpg",
          "https://lh5.googleusercontent.com/-n7mdm7I7FGs/URqueT_BT-I/AAAAAAAAAbs/9MYmXlmpSAo/s160-c/Bonzai%252520Rock%252520Sunset.jpg",
          "https://lh6.googleusercontent.com/-4CN4X4t0M1k/URqufPozWzI/AAAAAAAAAbs/8wK41lg1KPs/s160-c/Caterpillar.jpg",
          "https://lh3.googleusercontent.com/-rrFnVC8xQEg/URqufdrLBaI/AAAAAAAAAbs/s69WYy_fl1E/s160-c/Chess.jpg",
          "https://lh5.googleusercontent.com/-WVpRptWH8Yw/URqugh-QmDI/AAAAAAAAAbs/E-MgBgtlUWU/s160-c/Chihuly.jpg",
          "https://lh5.googleusercontent.com/-0BDXkYmckbo/URquhKFW84I/AAAAAAAAAbs/ogQtHCTk2JQ/s160-c/Closed%252520Door.jpg",
          "https://lh3.googleusercontent.com/-PyggXXZRykM/URquh-kVvoI/AAAAAAAAAbs/hFtDwhtrHHQ/s160-c/Colorado%252520River%252520Sunset.jpg",
          "https://lh6.googleusercontent.com/-9lzOk_OWZH0/URquoo4xYoI/AAAAAAAAAbs/AwgzHtNVCwU/s160-c/Frantic.jpg",
          "https://lh3.googleusercontent.com/-0X3JNaKaz48/URqupH78wpI/AAAAAAAAAbs/lHXxu_zbH8s/s160-c/Golden%252520Gate%252520Afternoon.jpg",
          "https://lh6.googleusercontent.com/-95sb5ag7ABc/URqupl95RDI/AAAAAAAAAbs/g73R20iVTRA/s160-c/Golden%252520Gate%252520Fog.jpg",
          "https://lh3.googleusercontent.com/-JB9v6rtgHhk/URqup21F-zI/AAAAAAAAAbs/64Fb8qMZWXk/s160-c/Golden%252520Grass.jpg",
          "https://lh4.googleusercontent.com/-EIBGfnuLtII/URquqVHwaRI/AAAAAAAAAbs/FA4McV2u8VE/s160-c/Grand%252520Teton.jpg",
          "https://lh4.googleusercontent.com/-WoMxZvmN9nY/URquq1v2AoI/AAAAAAAAAbs/grj5uMhL6NA/s160-c/Grass%252520Closeup.jpg",
          "https://lh3.googleusercontent.com/-6hZiEHXx64Q/URqurxvNdqI/AAAAAAAAAbs/kWMXM3o5OVI/s160-c/Green%252520Grass.jpg",
          "https://lh5.googleusercontent.com/-6LVb9OXtQ60/URquteBFuKI/AAAAAAAAAbs/4F4kRgecwFs/s160-c/Hanging%252520Leaf.jpg",
          "https://lh4.googleusercontent.com/-zAvf__52ONk/URqutT_IuxI/AAAAAAAAAbs/D_bcuc0thoU/s160-c/Highway%2525201.jpg",
          "https://lh6.googleusercontent.com/-H4SrUg615rA/URquuL27fXI/AAAAAAAAAbs/4aEqJfiMsOU/s160-c/Horseshoe%252520Bend%252520Sunset.jpg",
          "https://lh4.googleusercontent.com/-JhFi4fb_Pqw/URquuX-QXbI/AAAAAAAAAbs/IXpYUxuweYM/s160-c/Horseshoe%252520Bend.jpg",
          "https://lh5.googleusercontent.com/-UGgssvFRJ7g/URquueyJzGI/AAAAAAAAAbs/yYIBlLT0toM/s160-c/Into%252520the%252520Blue.jpg",
          "https://lh3.googleusercontent.com/-CH7KoupI7uI/URquu0FF__I/AAAAAAAAAbs/R7GDmI7v_G0/s160-c/Jelly%252520Fish%2525202.jpg",
          "https://lh4.googleusercontent.com/-pwuuw6yhg8U/URquvPxR3FI/AAAAAAAAAbs/VNGk6f-tsGE/s160-c/Jelly%252520Fish%2525203.jpg",
          "https://lh5.googleusercontent.com/-GoUQVw1fnFw/URquv6xbC0I/AAAAAAAAAbs/zEUVTQQ43Zc/s160-c/Kauai.jpg",
          "https://lh6.googleusercontent.com/-8QdYYQEpYjw/URquwvdh88I/AAAAAAAAAbs/cktDy-ysfHo/s160-c/Kyoto%252520Sunset.jpg",
          "https://lh4.googleusercontent.com/-vPeekyDjOE0/URquwzJ28qI/AAAAAAAAAbs/qxcyXULsZrg/s160-c/Lake%252520Tahoe%252520Colors.jpg",
          "https://lh4.googleusercontent.com/-xBPxWpD4yxU/URquxWHk8AI/AAAAAAAAAbs/ARDPeDYPiMY/s160-c/Lava%252520from%252520the%252520Sky.jpg",
          "https://lh3.googleusercontent.com/-897VXrJB6RE/URquxxxd-5I/AAAAAAAAAbs/j-Cz4T4YvIw/s160-c/Leica%25252050mm%252520Summilux.jpg",
          "https://lh5.googleusercontent.com/-qSJ4D4iXzGo/URquyDWiJ1I/AAAAAAAAAbs/k2pBXeWehOA/s160-c/Leica%25252050mm%252520Summilux.jpg",
          "https://lh6.googleusercontent.com/-dwlPg83vzLg/URquylTVuFI/AAAAAAAAAbs/G6SyQ8b4YsI/s160-c/Leica%252520M8%252520%252528Front%252529.jpg",
          "https://lh3.googleusercontent.com/-R3_EYAyJvfk/URquzQBv8eI/AAAAAAAAAbs/b9xhpUM3pEI/s160-c/Light%252520to%252520Sand.jpg",
          "https://lh3.googleusercontent.com/-fHY5h67QPi0/URqu0Cp4J1I/AAAAAAAAAbs/0lG6m94Z6vM/s160-c/Little%252520Bit%252520of%252520Paradise.jpg",
          "https://lh5.googleusercontent.com/-TzF_LwrCnRM/URqu0RddPOI/AAAAAAAAAbs/gaj2dLiuX0s/s160-c/Lone%252520Pine%252520Sunset.jpg",
          "https://lh3.googleusercontent.com/-4HdpJ4_DXU4/URqu046dJ9I/AAAAAAAAAbs/eBOodtk2_uk/s160-c/Lonely%252520Rock.jpg",
          "https://lh6.googleusercontent.com/-erbF--z-W4s/URqu1ajSLkI/AAAAAAAAAbs/xjDCDO1INzM/s160-c/Longue%252520Vue.jpg",
          "https://lh6.googleusercontent.com/-0CXJRdJaqvc/URqu1opNZNI/AAAAAAAAAbs/PFB2oPUU7Lk/s160-c/Look%252520Me%252520in%252520the%252520Eye.jpg",
          "https://lh6.googleusercontent.com/-6WS5DoCGuOA/URqu5qx1UgI/AAAAAAAAAbs/giMw2ixPvrY/s160-c/Open%252520Sky.jpg",
          "https://lh6.googleusercontent.com/-u8EHKj8G8GQ/URqu55sM6yI/AAAAAAAAAbs/lIXX_GlTdmI/s160-c/Orange%252520Sunset.jpg",
          "https://lh6.googleusercontent.com/-74Z5qj4bTDE/URqu6LSrJrI/AAAAAAAAAbs/XzmVkw90szQ/s160-c/Orchid.jpg",
          "https://lh6.googleusercontent.com/-lEQE4h6TePE/URqu6t_lSkI/AAAAAAAAAbs/zvGYKOea_qY/s160-c/Over%252520there.jpg",
          "https://lh5.googleusercontent.com/-cauH-53JH2M/URqu66v_USI/AAAAAAAAAbs/EucwwqclfKQ/s160-c/Plumes.jpg",
          "https://lh3.googleusercontent.com/-eDLT2jHDoy4/URqu7axzkAI/AAAAAAAAAbs/iVZE-xJ7lZs/s160-c/Rainbokeh.jpg",
          "https://lh5.googleusercontent.com/-j1NLqEFIyco/URqu8L1CGcI/AAAAAAAAAbs/aqZkgX66zlI/s160-c/Rainbow.jpg",
          "https://lh5.googleusercontent.com/-DRnqmK0t4VU/URqu8XYN9yI/AAAAAAAAAbs/LgvF_592WLU/s160-c/Rice%252520Fields.jpg",
          "https://lh3.googleusercontent.com/-hwh1v3EOGcQ/URqu8qOaKwI/AAAAAAAAAbs/IljRJRnbJGw/s160-c/Rockaway%252520Fire%252520Sky.jpg",
        };
    }

    main.xml如下:

    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent" >
      
        <ListView 
            android:id="@+id/listView"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
         >
            
        </ListView>
    
    </RelativeLayout>

    listviewitem.xml如下:

    <?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:orientation="horizontal" >
        
        <ImageView 
            android:id="@+id/imageview"
            android:layout_width="70dip" 
            android:layout_height="70dip"
            
         />
        <TextView 
            android:id="@+id/textView"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="130dip"
            android:layout_marginTop="25dip"
         />
        
    
    </LinearLayout>
  • 相关阅读:
    小程序样式表不支持级联选择器
    小程序为什么脚本内不能使用window等对象
    微信小程序怎么获取用户输入
    php中不借助IDE快速定位行数或者方法定义的文件和位置
    百度Ueditor编辑器取消多图上传对话框中的图片搜索
    阿里云ECS购买优惠码
    DEDE 5.7中各函数所在的文件和位置
    自定义的parse_url逆向函数http_build_url,将数组转为url字符串
    PHPMailer fe v4.11 For Thinkphp 3.2
    javascript使用技巧总结,不断更新...
  • 原文地址:https://www.cnblogs.com/cmblogs/p/4224320.html
Copyright © 2020-2023  润新知