I have been using Image loader class for lazy loading in list view. It

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Asked: May 25, 20262026-05-25T21:04:01+00:00 2026-05-25T21:04:01+00:00

I have been using Image loader class for lazy loading in list view. It

0

I have been using Image loader class for lazy loading in list view. It works fine but I have been dealing with lots of bitmap that will be downloaded from web service. so now I get bitmap size exceeds VM budget. Increased bitmapfactory size to be 32*1024 but if it reaches 32mb again it will throw a the error. It being breaking my head for the past one week. so some one please help me out of this problem. I here by post my image loader class as well please let me know where and how should I solve this problem.

public class ImageLoader {

private HashMap<String, Bitmap> cache=new HashMap<String, Bitmap>();
Bitmap bitmap = null;

private Activity activity;
PhotosLoader photoLoaderThread=new PhotosLoader();
public ImageLoader(Activity activity){
    this.activity = activity;
    photoLoaderThread.setPriority(Thread.NORM_PRIORITY-1);
    clearCache();
}
public void DisplayImage(String url, Activity activity, ImageView imageView, String[] imageUrl){
    this.activity = activity;
    if(cache.containsKey(url)){
        imageView.setImageBitmap(cache.get(url));

    }
else{
        imageView.setImageResource(R.drawable.icon);
        queuePhoto(url, activity, imageView);
    }    

}

private void queuePhoto(String url, Activity activity, ImageView imageView){
    this.activity = activity;
    photosQueue.Clean(imageView);
    PhotoToLoad p=new PhotoToLoad(url, imageView);
    synchronized(photosQueue.photosToLoad){
        photosQueue.photosToLoad.push(p);
        photosQueue.photosToLoad.notifyAll();
    }
    if(photoLoaderThread.getState()==Thread.State.NEW)
        photoLoaderThread.start();
}

public Bitmap getBitmap(String url, int sampleSize) throws Exception{
    Bitmap bm = null;
    try {
        URL request = new URL(url);
        InputStream is = (InputStream) request.getContent();
        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inDither = true;
        options.inPurgeable = true;
        options.inInputShareable = true;
        options.inSampleSize = sampleSize;
        options.inTempStorage = new byte[32 * 1024];

        bm = BitmapFactory.decodeStream(is, null, options);
        if (bm!=null)
        bm = Bitmap.createScaledBitmap(bm, 115,100, true);
        is.close();
        is = null;
    } catch (IOException e) {
        throw new Exception();
    } catch (OutOfMemoryError e) {
        bm.recycle();
        bm = null;
        System.gc();
        throw new Exception();
    }
    return bm;
}
private class PhotoToLoad{
    public String url;
    public ImageView imageView;
    public PhotoToLoad(String u, ImageView i){
        url=u; 
        imageView=i;
    }
}
PhotosQueue photosQueue=new PhotosQueue();
public void stopThread(){
    photoLoaderThread.interrupt();
}
static class  PhotosQueue{
    private Stack<PhotoToLoad> photosToLoad=new Stack<PhotoToLoad>();
    public void Clean(ImageView image){
        for(int j=0 ;j<photosToLoad.size();){
            try{
            if(photosToLoad.get(j).imageView==image)
                photosToLoad.remove(j);
            else
                ++j;
            }catch (Exception e) {
            }
        }
    }
}
class PhotosLoader extends Thread {
    public void run() {
        try {
            while(true){

                if(photosQueue.photosToLoad.size()==0)
                    synchronized(photosQueue.photosToLoad){
                        photosQueue.photosToLoad.wait();
                    }
                if(photosQueue.photosToLoad.size()!=0){
                    PhotoToLoad photoToLoad;
                    synchronized(photosQueue.photosToLoad){
                        photoToLoad=photosQueue.photosToLoad.pop();
                    }
                    Bitmap bmp = null;
                        bmp = getBitmap(photoToLoad.url, 1);
                    cache.put(photoToLoad.url, bmp);
                    if(((String)photoToLoad.imageView.getTag()).equals(photoToLoad.url)){
                        BitmapDisplayer bd=new BitmapDisplayer(bmp, photoToLoad.imageView);
                        Activity a=(Activity)photoToLoad.imageView.getContext();
                        a.runOnUiThread(bd);
                    }
                }
                if(Thread.interrupted())
                    break;
            }
        } catch (InterruptedException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}


class BitmapDisplayer implements Runnable{
    ImageView imageView;
    public  BitmapDisplayer(Bitmap b, ImageView i){
        bitmap = null;
        bitmap=b;
        imageView=i;
        }
    public void run(){
        if(bitmap!=null){
            imageView.setImageBitmap(bitmap);
            imageView.setScaleType(ScaleType.FIT_XY);
        }
        else{
            imageView.setImageResource(R.drawable.icon);
        }
    }
}

public void clearCache() {
    try{
    cache.clear();
    cache = new HashMap<String, Bitmap>();
    bitmap.recycle();   
    System.gc();
    }catch (Exception e) {
    }
}