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)
私のAndroidコードには、さまざまなフラグメントに表示する必要がある多くの画像があります。これらのいくつかは、アセットフォルダーに格納され、他はhttpリクエストから取得されます。 Java.lang.OutOfMemoryErrorに逆らわないように画像キャッシュを実装しますが、それでもこのエラーは続くようです。
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();
}
}
FileCache
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();
}
}
メモリーキャッシュ
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();
}
}
Utils
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){}
}
}
これを試してみると、このタグをマニフェストファイルに追加するのに役立ちます。
<application Android:largeHeap="true">
</application>
アプリに大きなヒープを割り当てます
大きなビットマップを効率的にロードする: http://developer.Android.com/training/displaying-bitmaps/load-bitmap.html =
キャッシュビットマップ:http://developer.Android.com/training/displaying-bitmaps/cache-bitmap.html
使用後にも画像のサイズを変更し、ビットマップをリサイクルしてください。
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)
}
}
これは、メモリが少ないため、画像ファイルのサイズが大きいため、この問題を解決するには、このメソッドをクラスに追加します。
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;
}
次に、これを使用する場所でこのメソッドを呼び出します。
Bitmap b = decodeFile(f);
このinstedを使用してください:
Bitmap b = decodeImageFile(f, 1280, 720);
OutOfMemoryErrorは、特にビットマップの処理中にAndroidで発生した最も一般的な問題です。このエラーは、Java Virtual Machine( JVM)メモリスペース不足のためにオブジェクトを割り当てることができず、ガベージコレクターが一部のスペースを解放できない場合。
Alekseyが述べたように、マニフェストファイルAndroid:hardwareAccelerated = "false"、Android:largeHeap = "true"に以下のエンティティを追加できます。これは一部の環境で機能します。
<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">
<application
Android:allowBackup="true"
Android:icon="@mipmap/ic_launcher"
Android:label="@string/app_name"
Android:largeHeap="true"/>