自定义PullToRefreshListView继承ListView，在ListView头部添加一个下拉的头部布局。跟ListView用法完全一致。
该自定义Listview代码详解具体可参考：
/wwj_748/article/details/12512885
此处详细介绍Adapter的详细代码。
1.首先给Adapter绑定ListView布局。
2.其次创建一个层次对应组件的类，将对应的组件和对象进行关联，提高效率。
3.然后跟陆获得的图片路径异步下载图片，由于不知道该微博图片的数量，所以在listview中添加一个GirlView控件或者GirlLayout布局，然后将得到的图片添加到其中，并按指定属性值排列好。
*** Created by D&LL on /6/2.*/public class WeiboAdapter extends BaseAdapter {/*** 为提高效率，缓存数据准备的一个自定义类 对应一条微博数据*/class WeiboHolder {public ImageView wbicon;public TextView wbtext, wbtime, wbuser;}private HomeActivity homeActivity = null;//数据集public ArrayList<WeiBoInfo> weiboList = null;public WeiboAdapter(HomeActivity homeActivity, ArrayList<WeiBoInfo> weiboList) {this.homeActivity = homeActivity;this.weiboList = weiboList;}//微博图片的异步下载类AsyncImageLoader asyncImageLoader;@Overridepublic View getView(int position, View convertView, ViewGroup parent) {asyncImageLoader = new AsyncImageLoader();//记载微博的每条需要显示在什么布局上的布局对象convertView = LayoutInflater.from(this.homeActivity.getApplicationContext()).inflate(R.layout.listview,null);//创建一个层次对应组件的类WeiboHolder wh = new WeiboHolder();//将对应的组件和对象进行关联，提高效率wh.wbicon = (ImageView) convertView.findViewById(R.id.wbicon);wh.wbtext = (TextView) convertView.findViewById(R.id.wbtext);wh.wbtime = (TextView) convertView.findViewById(R.id.wbtime);wh.wbuser = (TextView) convertView.findViewById(R.id.wbuser);/* wh.wbimage = (ImageView) convertView.findViewById(R.id.wbimage);*///获得一条微博数据WeiBoInfo wb = this.weiboList.get(position);if (wb != null) {convertView.setTag(wb.getId());wh.wbuser.setText(wb.getUserName());wh.wbtime.setText(wb.getTime());wh.wbtext.setText(StringUtils.getEmotionContent(convertView.getContext(), wh.wbtext, wb.getText()), TextView.BufferType.SPANNABLE);if (wb.getHaveImage()) {// 是否有图片信息//异步加载图片内容Drawable[] wb_image = new Drawable[wb.getImage_context().length];ImageView[] wbimage = new ImageView[wb.getImage_context().length];GridLayout layout = (GridLayout) convertView.findViewById(R.id.imagelayout);//遍历下载所有图片 并添加到listview中for (int i = 0; i < wb.getImage_context().length; i++) {wbimage[i] = new ImageView(this.homeActivity.getApplicationContext());wbimage[i].setPadding(5, 5, 5, 5);wbimage[i].setScaleType(ImageView.ScaleType.FIT_XY);GridLayout.Spec row = GridLayout.spec(i / 3);GridLayout.Spec colum = GridLayout.spec(i % 3);GridLayout.LayoutParams params = new GridLayout.LayoutParams(row, colum);params.setGravity(Gravity.FILL);params.width = 250;params.height = 250;wb_image[i] = asyncImageLoader.loadDrawable(wb.getImage_context()[i],wbimage[i], new AsyncImageLoader.ImageCallback() {@Overridepublic void imageLoaded(Drawable imageDrawable, ImageView imageView, String imageUrl) {imageView.setImageDrawable(imageDrawable);}});wbimage[i].setImageDrawable(wb_image[i]);layout.addView(wbimage[i], params);}}//异步加载用户头像数据Drawable cachedImage = asyncImageLoader.loadDrawable(wb.getUserIcon(), wh.wbicon, new AsyncImageLoader.ImageCallback() {@Overridepublic void imageLoaded(Drawable imageDrawable, ImageView imageView, String imageUrl) {imageView.setImageDrawable(imageDrawable);}});if (cachedImage == null) {} else {wh.wbicon.setImageDrawable(cachedImage);}}return convertView;}@Overridepublic int getCount() {return this.weiboList.size();}@Overridepublic Object getItem(int position) {return this.weiboList.get(position);}@Overridepublic long getItemId(int position) {return position;}}
异步下载图片的方法。使用SoftReference是软引用，是为了系统更好的回收变量；从缓存中获取图片路径后，建立新一个新的线程下载图片。
*** Created by D&LL on /6/2.*/public class AsyncImageLoader {//SoftReference是软引用，是为了更好的为了系统回收变量private HashMap<String, SoftReference<Drawable>> imageCache;public AsyncImageLoader() {imageCache = new HashMap<String, SoftReference<Drawable>>();}public Drawable loadDrawable(final String imageUrl, final ImageView imageView, final ImageCallback imageCallback) {if (imageCache.containsKey(imageUrl)) {//从缓存中获取SoftReference<Drawable> softReference = imageCache.get(imageUrl);Drawable drawable = softReference.get();if (drawable != null) {return drawable;}}final Handler handler = new Handler() {public void handleMessage(Message message) {imageCallback.imageLoaded((Drawable) message.obj, imageView, imageUrl);}};//建立新一个新的线程下载图片new Thread() {@Overridepublic void run() {Drawable drawable = loadImageFromUrl(imageUrl);imageCache.put(imageUrl, new SoftReference<Drawable>(drawable));Message message = handler.obtainMessage(0, drawable);handler.sendMessage(message);}}.start();return null;}public static Drawable loadImageFromUrl(String url) {URL m;InputStream i = null;try {m = new URL(url);i = (InputStream) m.getContent();} catch (MalformedURLException e1) {e1.printStackTrace();} catch (IOException e) {e.printStackTrace();}Drawable d = Drawable.createFromStream(i, "src");return d;}//回调接口public interface ImageCallback {public void imageLoaded(Drawable imageDrawable, ImageView imageView, String imageUrl);}}
