先给大家展示效果图，看看是大家想要的效果吗，如果还满意，请参考以下代码：
前言
UniversalImageLoader是用于加载图片的一个开源项目，在其项目介绍中是这么写的，
•支持多线程图片加载
•提供丰富的细节配置，比如线程池大小，HTPP请求项，内存和磁盘缓存，图片显示时的参数配置等等；
•提供双缓存
•支持加载过程的监听；
•提供图片的个性化显示配置接口；
•Widget支持(这个，个人觉得没必要写进来，不过尊重原文)
其他类似的项目也有很多，但这个作为github上著名的开源项目被广泛使用。第三方的包虽然好用省力，可以有效避免重复造轮子，但是却隐藏了一些开发上的细节，如果不关注其内部实现，那么将不利于开发人员掌握核心技术，当然也谈不上更好的使用它，计划分析项目的集成使用和低层实现。
我从接口拉出来的数据然后将它们展示在界面上
1 先定义布局 我定义了MyGridView来展示商品
2 导入jar包universal-image-loader-1.8.6-with-sources 用来展示商品使用 在使用 ImageLoader应加入
ImageLoader.getInstance().init(ImageLoaderConfiguration.createDefault(this));不然会报
java.lang.IllegalStateException: ImageLoader must be init with configuration before using字面意思是在使用前要初始化
3 定义适配器在getView中展示产品，不过我在展示的时候发现第一条数据总是在请求数据如下图，重复网址加载太慢也消耗服务器（也不知道是我哪里写错了第0条在重复请求 在网上我也没找到方法）
所以我定义了一个 View arrView[]有数据的时候就不许再请求了
4 开启子线程 在子线程中加载数据，在handler中解析数据并将其展示在界面上
主要的代码如下
布局代码
package com.demo.content; import android.content.Context; import android.util.AttributeSet; import android.widget.GridView; public class MyGridView extends GridView { public MyGridView(Context context, AttributeSet attrs) { super(context, attrs); } public MyGridView(Context context) { super(context); } public MyGridView(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); } @Override public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { int expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2, MeasureSpec.AT_MOST); super.onMeasure(widthMeasureSpec, expandSpec); } } <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <ScrollView android:layout_width="match_parent" android:layout_height="match_parent" > <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:background="#eee" android:orientation="vertical" > <Button android:layout_width="match_parent" android:layout_height="wrap_content" android:text="@string/app_name" android:textColor="#000" /> <View android:layout_width="match_parent" android:layout_height="5dp" android:background="@drawable/btn_normal" /> <com.demo.content.MyGridView android:id="@+id/gg_mygridview" android:layout_width="match_parent" android:layout_height="match_parent" android:horizontalSpacing="7dp" android:numColumns="2" android:verticalSpacing="7dp" /> </LinearLayout> </ScrollView> </LinearLayout> package com.demo.activity; import java.util.ArrayList; import java.util.List; import org.json.JSONArray; import org.json.JSONObject; import com.demo.content.MyGridView; import com.demo.entity.Product; import com.demo.pullrefresh.R; import com.demo.util.GetThread; import com.nostra.universalimageloader.core.DisplayImageOptions; import com.nostra.universalimageloader.core.ImageLoader; import com.nostra.universalimageloader.core.ImageLoaderConfiguration; import com.nostra.universalimageloader.core.assist.ImageScaleType; import com.nostra.universalimageloader.core.display.FadeInBitmapDisplayer; import android.annotation.SuppressLint; import android.app.Activity; import android.graphics.Bitmap; import android.os.Bundle; import android.os.Handler; import android.util.Log; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.ImageView; import android.widget.TextView; public class MyMainActivity extends Activity { // 定义的布局 private MyGridView myGridView; private DisplayImageOptions options; // 产品 private List<Product> products; // 地址 private String url = "" + "Product/GetProductsByProType//"; @Override protected void onCreate(Bundle arg) { // TODO Auto-generated method stub super.onCreate(arg); setContentView(R.layout.mymainactivity); options = new DisplayImageOptions.Builder() .showImageForEmptyUri(R.drawable.ic_empty) // image连接地址为空时 .showImageOnFail(R.drawable.ic_error) // image加载失败 .resetViewBeforeLoading(true).cacheOnDisc(true) .imageScaleType(ImageScaleType.EXACTLY) .bitmapConfig(Bitmap.Config.RGB_) .displayer(new FadeInBitmapDisplayer())// 设置用户加载图片task（这里是渐现图片显示） .build(); // 创建默认的ImageLoader的参数 不加回报java.lang.IllegalStateException // 但不是每次用到ImageLoader都要加 ImageLoader.getInstance().init( ImageLoaderConfiguration.createDefault(this)); myGridView = (MyGridView) findViewById(R.id.gg_mygridview); // 开启线程 new GetThread(url, handler).start(); } @SuppressLint("HandlerLeak") private Handler handler = new Handler() { public void handleMessage(android.os.Message msg) { switch (msg.what) { case GetThread.SUCCESS: String jsonString = (String) msg.obj; // 用JSON来解析数据 products = getJsonProducts(jsonString); Log.d("jiejie", "DDDDDDD" + products); // 创建个适配器 Adapter adapter = new Adapter(); myGridView.setAdapter(adapter); break; default: break; } }; }; protected List<Product> getJsonProducts(String jsonString) { List<Product> resultTempList = new ArrayList<Product>(); try { JSONArray array = new JSONArray(jsonString); for (int i = ; i < array.length(); i++) { Product temProductSimple = new Product(); JSONObject object = array.getJSONObject(i); temProductSimple.setId(object.getInt("id")); temProductSimple.setProType(object.getInt("ProType")); temProductSimple.setProOrder(object.getInt("ProOrder")); temProductSimple.setAddTime(object.getString("AddTime")); temProductSimple.setTitle(object.getString("Title")); temProductSimple.setSmallPic(object.getString("SmallPic")); temProductSimple.setPrice(object.getDouble("Price")); temProductSimple.setSalePrice(object.getDouble("SalePrice")); temProductSimple.setZhishubi(object.getString("Zhishubi")); temProductSimple.setProNo(object.getString("ProNo")); temProductSimple.setContens(object.getString("Contens")); temProductSimple.setBuyCount(object.getInt("BuyCount")); temProductSimple.setReadCount(object.getInt("ReadCount")); temProductSimple.setProImg(object.getString("ProImg")); temProductSimple.setShopFlag(object.getString("ShopFlag")); temProductSimple.setBrandId(object.getInt("BrandId")); temProductSimple.setStartTime(object.getString("StartTime")); if (object.get("Score") == null || object.get("Score").toString() == "null") { temProductSimple.setScore(); } else { temProductSimple.setScore(object.getInt("Score")); } temProductSimple.setProductOrigin(object .getString("ProductOrigin")); if (object.get("kucun").toString() == "null") { temProductSimple.setKucun(); } else { temProductSimple.setKucun(object.getInt("kucun")); } resultTempList.add(temProductSimple); } } catch (Exception e) { // TODO: handle exception e.printStackTrace(); System.out.println(e.toString()); } return resultTempList; } private View arrView[]; private class Adapter extends BaseAdapter { @Override public int getCount() { // TODO Auto-generated method stub // return products.size(); if (arrView == null) { arrView = new View[products.size()]; } return products.size(); } @Override public Object getItem(int arg) { // TODO Auto-generated method stub return products.get(arg); } @Override public long getItemId(int arg) { // TODO Auto-generated method stub return arg; } @Override public View getView(int arg, View arg, ViewGroup arg) { if (arrView[arg] == null) { Product info = products.get(arg); Holder holder = null; if (null == arg) { holder = new Holder(); arg = View.inflate(MyMainActivity.this, R.layout.product_item, null); holder.product_cost = (TextView) arg .findViewById(R.id.product_cost); holder.product_title = (TextView) arg .findViewById(R.id.product_title); holder.product_img = (ImageView) arg .findViewById(R.id.product_img); holder.buy_count = (TextView) arg .findViewById(R.id.buy_count); arg.setTag(holder); } else { holder = (Holder) arg.getTag(); } holder.product_cost.setText(products.get(arg).getSalePrice() + ""); holder.product_title.setText(products.get(arg).getTitle()); holder.buy_count.setText(products.get(arg).getBuyCount() + ""); String urlString = "http://**/UploadImages/ProductImages/" + products.get(arg).getSmallPic(); Log.d("jiejie", "dddddd___ " + arg); Log.d("jiejie", "_________" + info.getTitle()); Log.d("jiejie", "ProducteGridAdapter--" + urlString); ImageLoader.getInstance().displayImage(urlString, holder.product_img, options); arrView[arg] = arg; } return arrView[arg]; // return arg; } } static class Holder { ImageView product_img; TextView product_title; TextView product_cost; TextView buy_count; } } package com.demo.util; import java.io.IOException; import org.apache.http.HttpResponse; import org.apache.http.HttpStatus; import org.apache.http.client.ClientProtocolException; import org.apache.http.client.HttpClient; import org.apache.http.client.methods.HttpGet; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.util.EntityUtils; import android.os.Handler; import android.os.Message; import android.util.Log; public class GetThread extends Thread { public static final int SUCCESS = 10, FAIL = -11; private String url; private Handler handler; public GetThread(String url, Handler handler) { this.url = url; this.handler = handler; } @Override public void run() { // TODO Auto-generated method stub super.run(); HttpClient httpClient = new DefaultHttpClient(); HttpGet httpGet = new HttpGet(url); try { HttpResponse httpResponse = httpClient.execute(httpGet); Message msg = Message.obtain(); Log.v("asdf", httpResponse.getStatusLine().getStatusCode() + "返回码 " + url); if (httpResponse.getStatusLine().getStatusCode() == HttpStatus.SC_OK) { String jsonString = EntityUtils.toString(httpResponse .getEntity()); msg.what = SUCCESS; msg.obj = jsonString; handler.sendMessage(msg); } else { msg.what = FAIL; handler.sendMessage(msg); } } catch (ClientProtocolException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } }
以上代码是脚本之家小编给大家介绍的Android开发之ImageLoader基本使用，有问题欢迎大家留言，我会及时和大家回复的，谢谢！