android – Imageloader类在库中创建lazylist文件夹.如何避免它

我正在使用imageLoader类从url载入图像.但是这些图像都是通过名为LazyList的文件夹名存储在图库中.它需要高达40-100 mb的内存.但是我不想加载该图像,因为用户可能会感到不适.对不起,英文不好

一切工作正常,但它在画廊中创建一个文件夹,并显示我的应用程序正在使用的所有图像.所以我觉得用户会感到不舒服的我的应用程序.

这是我的图像加载器的代码,并且它连接几个其他类甚至

public class ImageLoader {
MemoryCache memoryCache = new MemoryCache();
FileCache fileCache;
private Map<ImageView,String> imageViews = Collections
        .synchronizedMap(new WeakHashMap<ImageView,String>());
ExecutorService executorService;

public ImageLoader(Context context) {
    fileCache = new FileCache(context);
    executorService = Executors.newFixedThreadPool(5);
}

final int stub_id = R.drawable.abs__ab_bottom_transparent_light_holo;

public void displayImage(String url,ImageView imageView) {
    imageViews.put(imageView,url);
    Bitmap bitmap = memoryCache.get(url);
    if (bitmap != null)
        imageView.setimageBitmap(bitmap);
    else {
        queuePhoto(url,imageView);
        imageView.setimageResource(stub_id);
    }
}

private void queuePhoto(String url,ImageView imageView) {
    PhotoToLoad p = new PhotoToLoad(url,imageView);
    executorService.submit(new Photosloader(p));
}

private Bitmap getBitmap(String url) {
    File f = fileCache.getFile(url);
    // from SD cache
    Bitmap b = decodeFile(f);
    if (b != null)
        return b;
    // from web
    try {
        Bitmap bitmap = null;
        URL imageUrl = new URL(url);
        HttpURLConnection conn = (HttpURLConnection) imageUrl
                .openConnection();
        conn.setConnectTimeout(30000);
        conn.setReadTimeout(30000);
        conn.setInstanceFollowRedirects(true);
        InputStream is = conn.getInputStream();
        OutputStream os = new FileOutputStream(f);
        Utils.copyStream(is,os);
        os.close();
        bitmap = decodeFile(f);
        return bitmap;
    } catch (Exception ex) {
        ex.printstacktrace();
        return null;
    }
}

// decodes image and scales it to reduce memory consumption
private Bitmap decodeFile(File f) {
    try {
        // decode image size
        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inJustDecodeBounds = true;
        BitmapFactory.decodeStream(new FileInputStream(f),null,o);
        // Find the correct scale value. It should be the power of 2.
        final int required_SIZE = 100;
        int width_tmp = o.outWidth,height_tmp = o.outHeight;
        int scale = 1;
        while (true) {
            if (width_tmp / 2 < required_SIZE
                    || height_tmp / 2 < required_SIZE)
                break;
            width_tmp /= 2;
            height_tmp /= 2;
            scale *= 2;
        }
        // decode with inSampleSize
        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize = scale;
        return BitmapFactory.decodeStream(new FileInputStream(f),o2);
    } catch (FileNotFoundException e) {
    }
    return null;
}

// Task for the queue
private class PhotoToLoad {
    public String url;
    public ImageView imageView;

    public PhotoToLoad(String u,ImageView i) {
        url = u;
        imageView = i;
    }
}

class Photosloader implements Runnable {
    PhotoToLoad photoToLoad;

    Photosloader(PhotoToLoad photoToLoad) {
        this.photoToLoad = photoToLoad;
    }

    @Override
    public void run() {
        if (imageViewReused(photoToLoad))
            return;
        Bitmap bmp = getBitmap(photoToLoad.url);
        memoryCache.put(photoToLoad.url,bmp);
        if (imageViewReused(photoToLoad))
            return;
        Bitmapdisplayer bd = new Bitmapdisplayer(bmp,photoToLoad);
        Activity a = (Activity) photoToLoad.imageView.getContext();
        a.runOnUiThread(bd);
    }
}

boolean imageViewReused(PhotoToLoad photoToLoad) {
    String tag = imageViews.get(photoToLoad.imageView);
    if (tag == null || !tag.equals(photoToLoad.url))
        return true;
    return false;
}

// Used to display bitmap in the UI thread
class Bitmapdisplayer implements Runnable {
    Bitmap bitmap;
    PhotoToLoad photoToLoad;

    public Bitmapdisplayer(Bitmap b,PhotoToLoad p) {
        bitmap = b;
        photoToLoad = p;
    }

    public void run() {
        if (imageViewReused(photoToLoad))
            return;
        if (bitmap != null)
            photoToLoad.imageView.setimageBitmap(bitmap);
        else
            photoToLoad.imageView.setimageResource(stub_id);
    }
}

public void clearCache() {
    memoryCache.clear();
    fileCache.clear();
}
}

解决方法

我通过更改我的FileCache类及其目标文件夹得到我的解决方案

public class FileCache {
    private File cacheDir;
    private File nomediaFile;
    String NOMEDIA = " .nomedia";
public FileCache(Context context) {
    // Find the dir to save cached images
    if (android.os.Environment.getExternalStorageState().equals(
            android.os.Environment.MEDIA_MOUNTED)) {
        cacheDir = new File(Environment.getExternalStorageDirectory()
                + "/mydir");
        if (cacheDir.mkdir()) {
            nomediaFile = new File(
                    Environment.getExternalStorageDirectory() + "/mydir/"
                            + NOMEDIA);
            if (!nomediaFile.exists()) {
                try {
                    nomediaFile.createNewFile();
                } catch (IOException e) {
                    // Todo Auto-generated catch block
                    e.printstacktrace();
                }
            }
        }
    } else {
        cacheDir = context.getCacheDir();
    }
    if (!cacheDir.exists())
        cacheDir.mkdirs();
}

public File getFile(String url) {
    // I identify images by hashcode. Not a perfect solution,good for the
    // demo.
    // String filename=String.valueOf(url.hashCode());
    // Another possible solution (thanks to grantland)
    @SuppressWarnings("deprecation")
    String filename = URLEncoder.encode(url);
    File f = new File(cacheDir,filename);
    return f;

}

public void clear() {
    File[] files = cacheDir.listFiles();
    if (files == null)
        return;
    for (File f : files)
        f.delete();
}
}