/** * 异步线程加载图片工具类 * 使用说明： * BitmapManager bmpManager; * bmpManager = new BitmapManager(BitmapFactory.decodeResource(context.getResources(), R.drawable.loading)); * bmpManager.loadBitmap(imageURL, imageView); */public class BitmapManager {            private static HashMap
     
      > cache;      private static ExecutorService pool;      private static Map
      
        imageViews;      private Bitmap defaultBmp;          static {          cache = new HashMap
       
        >();          pool = Executors.newFixedThreadPool(5);  //固定线程池        imageViews = Collections.synchronizedMap(new WeakHashMap
        
         ());    }          public BitmapManager(){}        public BitmapManager(Bitmap def) {        this.defaultBmp = def;    }        /**     * 设置默认图片     * @param bmp     */    public void setDefaultBmp(Bitmap bmp) {          defaultBmp = bmp;      }         /**     * 加载图片     * @param url     * @param imageView     */    public void loadBitmap(String url, ImageView imageView) {          loadBitmap(url, imageView, this.defaultBmp, 0, 0);    }        /**     * 加载图片-可设置加载失败后显示的默认图片     * @param url     * @param imageView     * @param defaultBmp     */    public void loadBitmap(String url, ImageView imageView, Bitmap defaultBmp) {          loadBitmap(url, imageView, defaultBmp, 0, 0);    }        /**     * 加载图片-可指定显示图片的高宽     * @param url     * @param imageView     * @param width     * @param height     */    public void loadBitmap(String url, ImageView imageView, Bitmap defaultBmp, int width, int height) {          imageViews.put(imageView, url);          Bitmap bitmap = getBitmapFromCache(url);             if (bitmap != null) {              //显示缓存图片            imageView.setImageBitmap(bitmap);          } else {              //加载SD卡中的图片缓存            String filename = FileUtils.getFileName(url);            String filepath = imageView.getContext().getFilesDir() + File.separator + filename;            File file = new File(filepath);            if(file.exists()){                //显示SD卡中的图片缓存                Bitmap bmp = ImageUtils.getBitmap(imageView.getContext(), filename);                imageView.setImageBitmap(bmp);            }else{                //线程加载网络图片                imageView.setImageBitmap(defaultBmp);                queueJob(url, imageView, width, height);            }        }      }        /**     * 从缓存中获取图片     * @param url     */    public Bitmap getBitmapFromCache(String url) {          Bitmap bitmap = null;        if (cache.containsKey(url)) {              bitmap = cache.get(url).get();          }          return bitmap;      }          /**     * 从网络中加载图片     * @param url     * @param imageView     * @param width     * @param height     */    public void queueJob(final String url, final ImageView imageView, final int width, final int height) {          /* Create handler in UI thread. */          final Handler handler = new Handler() {              public void handleMessage(Message msg) {                  String tag = imageViews.get(imageView);                  if (tag != null && tag.equals(url)) {                      if (msg.obj != null) {                          imageView.setImageBitmap((Bitmap) msg.obj);                          try {                            //向SD卡中写入图片缓存                            ImageUtils.saveImage(imageView.getContext(), FileUtils.getFileName(url), (Bitmap) msg.obj);                        } catch (IOException e) {                            e.printStackTrace();                        }                    }                 }              }          };            pool.execute(new Runnable() {               public void run() {                  Message message = Message.obtain();                  message.obj = downloadBitmap(url, width, height);                  handler.sendMessage(message);              }          });      }       /**     * 下载图片-可指定显示图片的高宽     * @param url     * @param width     * @param height     */    private Bitmap downloadBitmap(String url, int width, int height) {           Bitmap bitmap = null;        try {            //http加载图片            bitmap = ApiClient.getNetBitmap(url);            if(width > 0 && height > 0) {                //指定显示图片的高宽                bitmap = Bitmap.createScaledBitmap(bitmap, width, height, true);            }             //放入缓存            cache.put(url, new SoftReference
         
          (bitmap));        } catch (AppException e) {            e.printStackTrace();        }        return bitmap;      }  }