可能重复:
Out Of memory error using Universal Image Loader and images getting refreshed
我一直在关注延迟加载列表视图中的图像的教程,而不是我实现LazyList。代码根据我的要求正常工作,但它在某些阶段给出Out Of Memory错误。我使用相同的ImageLoader,内存缓存,LazyAdapter,FileChache和Utils代码。 这是LazyAdapter类
public class LazyAdapter extends BaseAdapter {
private Activity activity;
private ArrayList<String> movieThumbnail;
private ArrayList<String> movieText;
private static LayoutInflater inflater=null;
public ImageLoader imageLoader;
public LazyAdapter(Activity a, ArrayList<String> movieThumbnail, ArrayList<String> movieText) {
activity = a;
/*data=d;*/
this.movieThumbnail = movieThumbnail;
this.movieText = movieText;
inflater = (LayoutInflater)activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
imageLoader=new ImageLoader(activity.getApplicationContext());
}
public int getCount() {
return movieText.size();
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
View vi=convertView;
if(convertView==null)
vi = inflater.inflate(R.layout.listrow, null);
TextView text=(TextView)vi.findViewById(R.id.rowListTextView);
ImageView image=(ImageView)vi.findViewById(R.id.movieImage);
text.setText(movieText.get(position));
imageLoader.DisplayImage(movieThumbnail.get(position), image);
return vi;
}
}
的MemoryCache
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()/6);
}
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();
}
}
ImageLoade类
public class ImageLoader {
MemoryCache memoryCache=new MemoryCache();
FileCache fileCache;
private Map<ImageView, String> imageViews=Collections.synchronizedMap(new WeakHashMap<ImageView, String>());
ExecutorService executorService;
Handler handler=new Handler();//handler to display images in UI thread
public ImageLoader(Context context){
fileCache=new FileCache(context);
executorService=Executors.newFixedThreadPool(5);
}
final int stub_id=R.drawable.ic_launcher;
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 (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;
FileInputStream stream1=new FileInputStream(f);
BitmapFactory.decodeStream(stream1,null,o);
stream1.close();
//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;
FileInputStream stream2=new FileInputStream(f);
Bitmap bitmap=BitmapFactory.decodeStream(stream2, null, o2);
stream2.close();
return bitmap;
} catch (FileNotFoundException e) {
}
catch (IOException e) {
e.printStackTrace();
}
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() {
try{
if(imageViewReused(photoToLoad))
return;
Bitmap bmp=getBitmap(photoToLoad.url);
memoryCache.put(photoToLoad.url, bmp);
if(imageViewReused(photoToLoad))
return;
BitmapDisplayer bd=new BitmapDisplayer(bmp, photoToLoad);
handler.post(bd);
}catch(Throwable th){
th.printStackTrace();
}
}
}
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();
}
}
答案 0 :(得分:4)
使用此方法进行图像加载当使用滚动而不是强制关闭时,这不会产生问题
MainClassActivity:
ArrayList<NewsItems> news = new ArrayList<NewsItems>();
SetListView sta;
sta = new SetListView(MainActivity.this, news);
lv.setAdapter(sta);
for (NewsItems s : news) {
s.loadImage(sta);
}
public class SetListView extends BaseAdapter{
private LayoutInflater inflater = null;
Activity activity;
ArrayList<NewsItems> one;
public SetListView(Activity a,ArrayList<NewsItems> one)
{
this.activity = a;
inflater = (LayoutInflater) a.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
this.one = one;
}
@Override
public int getCount() {
return one.size();
}
@Override
public Object getItem(int position) {
return position;
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View vi = convertView;
if (convertView == null)
vi = inflater.inflate(R.layout.main1, null);
TextView tv1 = (TextView) vi.findViewById(R.id.textView1);
TextView tv2 = (TextView) vi.findViewById(R.id.textView2);
tv1.setText(one.get(position).get_title());
tv2.setText(one.get(position).get_pudDate());
// Bitmap bm = loadBitmap(one.get(position).get_image());
if(one.get(position).get_bm() != null)
((ImageView)vi.findViewById(R.id.imageView1)).setImageBitmap(one.get(position).get_bm());
else
((ImageView)vi.findViewById(R.id.imageView1)).setImageResource(R.drawable.ic_launcher);
return vi;
}
}
package com.dudhat.classes;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;
import com.dudhat.rssfeeds.SetListView;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.util.Log;
public class NewsItems {
private SetListView sta;
String _title,_pudDate,_description,_image;
Bitmap _bm;
public Bitmap get_bm() {
return _bm;
}
public String get_image() {
return _image;
}
public String get_title() {
return _title;
}
public String get_pudDate() {
return _pudDate;
}
public String get_description() {
return _description;
}
public SetListView getAdapter() {
return sta;
}
public void setAdapter(SetListView sta) {
this.sta = sta;
}
public NewsItems(String _title,String _pubdate,String _description,String _image,Bitmap _bm)
{
this._description = _description;
this._pudDate = _pubdate;
this._title = _title;
this._image = _image;
this._bm = _bm;
}
public void loadImage(SetListView sta) {
this.sta = sta;
if (_image != null && !_image.equals("")) {
new ImageLoadTask().execute(_image);
}
}
private class ImageLoadTask extends AsyncTask<String, String, Bitmap> {
@Override
protected void onPreExecute() {
Log.i("ImageLoadTask", "Loading image...");
}
protected Bitmap doInBackground(String... param) {
Log.i("ImageLoadTask", "Attempting to load image URL: " + param[0]);
try {
Bitmap b = loadBitmap(param[0]);
return b;
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
protected void onPostExecute(Bitmap ret) {
if (ret != null) {
_bm = ret;
if (sta != null) {
sta.notifyDataSetChanged();
}
} else {
}
}
}
public Bitmap loadBitmap(String url)
{
Bitmap bm = null;
InputStream is = null;
BufferedInputStream bis = null;
try
{
URLConnection conn = new URL(url).openConnection();
conn.connect();
is = conn.getInputStream();
bis = new BufferedInputStream(is, 8192);
bm = BitmapFactory.decodeStream(bis);
}
catch (Exception e)
{
e.printStackTrace();
}
finally {
if (bis != null)
{
try
{
bis.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
if (is != null)
{
try
{
is.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
}
return bm;
}
}