出的内存缓存错误在应用程序中访问时， [英] Out of memory cache error when accessing inside the app

问题描述

我搜索了很多，但我不明白的地方是我的错误。 首先，在我的应用程序，我从网络上获得的图像，如果没有网络，我从创建数据库中获取它们。 我要发表我ImageLoader的类那么内存类则utils的类，如果有什么不对的请我需要提前一些帮助感谢。

I've searched a lot but I did not understand where to is my error. First in my app I am getting images from the web if there is no net I am getting them from created database. I am going to post my ImageLoader class then the memory class then the utils class if there is something wrong please I need some help Thanks in advance.

public class ClassImageLoader {

ClassMemoryCache memoryCache=new ClassMemoryCache();
ClassFileCache fileCache;
private Map<ImageView, String> imageViews=Collections.synchronizedMap(new WeakHashMap<ImageView, String>());
ExecutorService executorService; 

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

final int stub_id=R.drawable.restlogobutton;
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);
        ClassUtils.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=70;
        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), null, 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;
    }

    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();
}

}

public class ClassMemoryCache {

private Map<String, Bitmap> cache=Collections.synchronizedMap(
        new LinkedHashMap<String, Bitmap>(10,1.5f,true));//Last argument true for LRU ordering
private long size=0;//current allocated size
private long limit=1000000;//max memory in bytes

public ClassMemoryCache(){
    //use 25% of available heap size
    setLimit(Runtime.getRuntime().maxMemory()/4);
}

public void setLimit(long new_limit){
    limit=new_limit;
}

public Bitmap get(String id){
    if(!cache.containsKey(id))
        return null;
    return cache.get(id);
}

public void put(String id, Bitmap bitmap){
    try{
        if(cache.containsKey(id))
            size-=getSizeInBytes(cache.get(id));
        cache.put(id, bitmap);
        size+=getSizeInBytes(bitmap);
        checkSize();
    }catch(Throwable th){
        th.printStackTrace();
    }
}

private void checkSize() {
    if(size>limit){
        Iterator<Entry<String, Bitmap>> iter=cache.entrySet().iterator();//least recently accessed item will be the first one iterated  
        while(iter.hasNext()){
            Entry<String, Bitmap> entry=iter.next();
            size-=getSizeInBytes(entry.getValue());
            iter.remove();
            if(size<=limit)
                break;
        }
    }
}

public void clear() {
    cache.clear();
}

long getSizeInBytes(Bitmap bitmap) {
    if(bitmap==null)
        return 0;
    return bitmap.getRowBytes() * bitmap.getHeight();
}

}

public class ClassUtils {
public static void CopyStream(InputStream is, OutputStream os)
{
    final int buffer_size=1024;
    try
    {
        byte[] bytes=new byte[buffer_size];
        for(;;)
        {
          int count=is.read(bytes, 0, buffer_size);
          if(count==-1)
              break;
          os.write(bytes, 0, count);
        }
    }
    catch(Exception ex){}
}

}

推荐答案

//替换此方法在code和尝试，我不知道它会解决你的错误，但是一旦你可以试试。

// replace this methods in your code and try I am not sure it will solve your error but once you can try.

private Bitmap getBitmap(String url) 
    {
        //I identify images by hashcode. Not a perfect solution, good for the demo.
        String filename=String.valueOf(url.hashCode());
        File f=new File(cacheDir, filename);

        //from SD cache
        Bitmap b = decodeFile(f);
        if(b!=null)
            return b;

        //from web
        try {
            Bitmap bitmap=null;
            InputStream is=new URL(url).openStream();
            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=70;
        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.inTempStorage = new byte[32*1024]; 
        o2.inSampleSize=scale;
        return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
    } catch (FileNotFoundException e) {}
    return null;
}

检查此链接为ImageLoaderClass： <一href="http://$c$c.google.com/p/vimeoid/source/browse/apk/src/com/fedorvlasov/lazylist/ImageLoader.java" rel="nofollow">http://$c$c.google.com/p/vimeoid/source/browse/apk/src/com/fedorvlasov/lazylist/ImageLoader.java

check this link for the ImageLoaderClass: http://code.google.com/p/vimeoid/source/browse/apk/src/com/fedorvlasov/lazylist/ImageLoader.java

OOM问题，检查此链接： <一href="http://stackoverflow.com/questions/477572/android-strange-out-of-memory-issue-while-loading-an-image-to-a-bitmap-object/823966#823966">Android:奇怪的内存不足的问题，同时加载图像为位图对象

OOM issue check this link: Android: Strange out of memory issue while loading an image to a Bitmap object

如果你仍然得到那么一个错误检查这一点，我很多搜索后，发现和解决了我的问题的一个环节： 的https://groups.google.com/forum/?fromgroups=#!topic/android-developers/vYWKY1Y6bUo

And if you still get an error then check this one link that I have found after many search and has solved my Problem: https://groups.google.com/forum/?fromgroups=#!topic/android-developers/vYWKY1Y6bUo

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