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安卓 java.lang.OutOfMemoryError？

androidperformancememory-leaksout-of-memoryimage-caching
17
04-25 08:19:10.111    2431-2603/com.example.francesco.guidedautorewithtabs E/art﹕ Throwing OutOfMemoryError "Failed to allocate a 4194316 byte allocation with 1983651 free bytes and 1937KB until OOM"
04-25 08:19:10.114    2431-2603/com.example.francesco.guidedautorewithtabs E/AndroidRuntime﹕ FATAL EXCEPTION: GLThread 285
Process: com.example.francesco.guidedautorewithtabs, PID: 2431
java.lang.OutOfMemoryError: Failed to allocate a 4194316 byte allocation with 1983651 free bytes and 1937KB until OOM
        at dalvik.system.VMRuntime.newNonMovableArray(Native Method)
        at android.graphics.Bitmap.nativeCreate(Native Method)
        at android.graphics.Bitmap.createBitmap(Bitmap.java:817)
        at android.graphics.Bitmap.createBitmap(Bitmap.java:794)
        at android.graphics.Bitmap.createBitmap(Bitmap.java:761)
        at com.google.maps.api.android.lib6.gmm6.o.c.l.a(Unknown Source)
        at com.google.maps.api.android.lib6.gmm6.o.c.o.a(Unknown Source)
        at com.google.maps.api.android.lib6.gmm6.o.c.o.a(Unknown Source)
        at com.google.maps.api.android.lib6.gmm6.o.c.o.b(Unknown Source)
        at com.google.maps.api.android.lib6.gmm6.o.c.b.ak.a(Unknown Source)
        at com.google.maps.api.android.lib6.gmm6.o.c.b.as.a(Unknown Source)
        at com.google.maps.api.android.lib6.gmm6.o.x.a(Unknown Source)
        at com.google.maps.api.android.lib6.gmm6.o.l.a(Unknown Source)
        at com.google.maps.api.android.lib6.gmm6.o.l.b(Unknown Source)
        at com.google.maps.api.android.lib6.gmm6.o.cj.g(Unknown Source)
        at com.google.maps.api.android.lib6.gmm6.o.cj.run(Unknown Source)

在我的Android代码中，我有很多需要显示在不同片段中的图像。其中一些存储在资产文件夹中，其他则从HTTP请求中获取。因此，我实现了图像缓存以避免出现java.lang.OutOfMemoryError错误，但是这个错误似乎仍然存在。我该如何解决这个问题？以下是我的图像缓存实现。

ImageLoader

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

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

final int stub_id= R.drawable.no_image;
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 getBitmapFromAsset(String strName)
{
    AssetManager assetManager = context.getAssets();
    InputStream istr = null;
    try {
        istr = assetManager.open(strName);
    } catch (IOException e) {
        e.printStackTrace();
    }
    Bitmap bitmap = BitmapFactory.decodeStream(istr);
    return bitmap;
}

private Bitmap getBitmap(String url)
{
    File f=fileCache.getFile(url);

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

    //from assets
    Bitmap bm = getBitmapFromAsset(url);

    if(bm!=null)
        return bm;

    //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 (Throwable ex){
        ex.printStackTrace();
        if(ex instanceof OutOfMemoryError)
            memoryCache.clear();
        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;
    }

    @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();
}
}

文件缓存

public class FileCache {

private File cacheDir;

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(android.os.Environment.getExternalStorageDirectory(),"TTImages_cache");
    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)
    //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();
}

}

内存缓存

public class MemoryCache {

private static final String TAG = "MemoryCache";
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 MemoryCache(){
    //use 25% of available heap size
    setLimit(Runtime.getRuntime().maxMemory()/4);
}

public void setLimit(long new_limit){
    limit=new_limit;
    Log.i(TAG, "MemoryCache will use up to "+limit/1024./1024.+"MB");
}

public Bitmap get(String id){
    try{
        if(!cache.containsKey(id))
            return null;
        //NullPointerException sometimes happen here http://code.google.com/p/osmdroid/issues/detail?id=78
        return cache.get(id);
    }catch(NullPointerException ex){
        ex.printStackTrace();
        return null;
    }
}

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() {
    Log.i(TAG, "cache size="+size+" length="+cache.size());
    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;
        }
        Log.i(TAG, "Clean cache. New size "+cache.size());
    }
}

public void clear() {
    try{
        //NullPointerException sometimes happen here http://code.google.com/p/osmdroid/issues/detail?id=78
        cache.clear();
        size=0;
    }catch(NullPointerException ex){
        ex.printStackTrace();
    }
}

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

工具类

public class Utils {
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){}
}
}
你知道这是来自你自己的图片吗？堆栈跟踪看起来像是源自Google Maps代码。 - Gus
@Gus 是的，但看看前4行...我想很快就会结束，无法分配内存映射。 - Francesco Lombardo
8个回答
36

尝试这个可能会有帮助 在您的清单文件中添加此标记。

<application android:largeHeap="true">
</application>

它将为您的应用程序分配大堆空间

目前似乎有效，添加了这个...谢谢 - Francesco Lombardo
7
明确一点：largeHeap 应该放在 application 标签中。此外，它不应被用作内存泄漏的修复方法，而只有在您的应用程序真正需要更多内存时才应使用。请参见 https://developer.android.com/training/articles/memory.html。 - espinchi
6
这个解决方案是错误的。你的应用程序存在内存泄漏。这个解决方案只会延迟问题，但不会修复泄漏。 - Nelson Osacky
这非常有用。 - bhavesh kaila
它能帮助处理“无法分配24字节内存，没有0个空闲字节和3GB可用内存直到OOM”这种类型的错误。 - Vivek Pratap Singh
显示剩余3条评论
9

高效加载大型位图： http://developer.android.com/training/displaying-bitmaps/load-bitmap.html

缓存位图： http://developer.android.com/training/displaying-bitmaps/cache-bitmap.html

尝试调整图像大小，并在使用后回收位图。

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;

 public class ImageResizer {

 public static Bitmap decodeSampledBitmapFromFile(String filename,
    int reqWidth, int reqHeight) {
// First decode with inJustDecodeBounds=true to check dimensions
final BitmapFactory.Options
        options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(filename, options);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
return BitmapFactory.decodeFile(filename, options);
 }

   public static int calculateInSampleSize(BitmapFactory.Options options,
    int reqWidth, int reqHeight) {
// BEGIN_INCLUDE (calculate_sample_size)
// Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;

if (height > reqHeight || width > reqWidth) {

    final int halfHeight = height / 2;
    final int halfWidth = width / 2;

    // Calculate the largest inSampleSize value that is a power of 2 and keeps both
    // height and width larger than the requested height and width.
    while ((halfHeight / inSampleSize) > reqHeight
            && (halfWidth / inSampleSize) > reqWidth) {
        inSampleSize *= 2;
    }

    // This offers some additional logic in case the image has a strange
    // aspect ratio. For example, a panorama may have a much larger
    // width than height. In these cases the total pixels might still
    // end up being too large to fit comfortably in memory, so we should
    // be more aggressive with sample down the image (=larger inSampleSize).

    long totalPixels = width * height / inSampleSize;

    // Anything more than 2x the requested pixels we'll sample down further
    final long totalReqPixelsCap = reqWidth * reqHeight * 2;

    while (totalPixels > totalReqPixelsCap) {
        inSampleSize *= 2;
        totalPixels /= 2;
    }
}
return inSampleSize;
// END_INCLUDE (calculate_sample_size)
 }
 }
你能看一下这个吗？http://stackoverflow.com/questions/29990186/android-skimagedecoderfactory-only-when-i-read-image-with-extension-png - Francesco Lombardo
4

这是由于内存不足导致的，您的图像文件大小较大，为解决此问题，请在您的类中添加以下方法：

public static Bitmap decodeImageFile(File f,int WIDTH,int HIGHT){
             try {
                 //Decode image size
                 BitmapFactory.Options o = new BitmapFactory.Options();
                 o.inJustDecodeBounds = true;
                 BitmapFactory.decodeStream(new FileInputStream(f),null,o);

                 //The new size we want to scale to
                 final int REQUIRED_WIDTH=WIDTH;
                 final int REQUIRED_HIGHT=HIGHT;
                 //Find the correct scale value. It should be the power of 2.
                 int scale=1;
                 while(o.outWidth/scale/2>=REQUIRED_WIDTH && o.outHeight/scale/2>=REQUIRED_HIGHT)
                     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;
            }

然后在使用此方法的地方调用它：
Bitmap b = decodeFile(f);

请使用这个替代：

Bitmap b = decodeImageFile(f, 1280, 720);
如果我的图像大于1280 x 720呢？此外，我主要从资产文件夹和HTTP请求中获取图像... 针对这些情况需要做哪些更改？ - Francesco Lombardo
@FrancescoLombardo，这解决了大图像的问题，唯一的限制是它会将大图像缩小至1280x720。 - Rahul Sharma
我使用这个解决方案解决了我的错误，如果您的设备支持大于1280x720，则可以尝试使用您自定义的分辨率来调用此方法。 - Rahul Sharma
我需要做哪些更改才能从资产文件夹解码位图？ - Francesco Lombardo
我已经实现了你的解决方案，谢谢！但是我遇到了另一个烦人的问题，你能看一下吗？http://stackoverflow.com/questions/29990186/android-skimagedecoderfactory-only-when-i-read-image-with-extension-png - Francesco Lombardo
0

OutOfMemoryError 是在处理位图时在Android上最常见的问题。当由于内存空间不足而无法分配对象，同时垃圾回收器无法释放一些空间时，Java虚拟机（JVM）会抛出此错误。

如Aleksey所述，您可以在Android清单文件中添加以下实体：android:hardwareAccelerated="false"，android:largeHeap="true"，这将适用于某些环境。

<application
    android:allowBackup="true"
    android:hardwareAccelerated="false"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:largeHeap="true"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
0

在你的清单文件中添加这个标签。

<application android:largeHeap="true"> </application>

0
    <application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:largeHeap="true"/>
-1
尝试在将图像加载到内存之前手动调用System.gc()，并且当您不需要使用此图像对象时也可以这样做。
即使您手动调用System.gc()，也不应该调用它。即使它被调用，它也会冻结应用程序一秒钟。因此，这是一个非常糟糕的建议。 - Oguz Ozcan
-2

你可以尝试这段代码...

BitmapFactory.Options options = new BitmapFactory.Options();
options.inSampleSize = 8;    

Bitmap bm = BitmapFactory.decodeFile(img,options);
imageView.setImageBitmap(bm);
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