Develop Reference

Downloading images from server and applying them as background for dynamically created buttons

Scenario : I have to download the images from server and set them as background for dynamically created buttons. Number of images keep changing, so I have to create that many number of buttons dynamically.
What I have completed so far : I successfully managed to download the images using AsyncTask and set them as background for dynamically created buttons. If there is no internet connection or if images are not downloaded for some reason then setting the background of each buttons to some default image.
Problem : Everything works so fine on phone, i.e downloading images and creating buttons dynamically depending upon the number of images and setting images as background for them. Now when I run the same program on Tablet it is not working. Buttons are not getting generated dynamically. But if I turn of the internet connection and then run, wonder happens.! Everything works fine i.e buttons are dynamically generated with the default image as their background. I'm not able to understand why is it so.! Is there any problem with AsyncTask? Any help will be appreciated..
Here is the AsyncTask
public class GetsImages extends AsyncTask<String, Void, Bitmap> {
FileCache fileCache;
ProgressDialog pd;
String url;
GetImages task = null;
Context context;
private Bitmap image;
HomeDynamic activity;
AsyncImage responseImage = null;
public GetImages(String url, HomeDynamic activity) {
this.url = url;
// this.context = context;
this.responseImage = activity;
attach(activity);
fileCache = new FileCache(activity);
//pd = new ProgressDialog(activity);
}
public GetImages(Context context) {
this.context = context;
}
protected void onPreExecute() {
super.onPreExecute();
/*pd.setTitle("Processing");
pd.setMessage("Please wait...");
pd.setCancelable(false);
pd.setIndeterminate(true);
pd.show();*/
}
#Override
protected void onPostExecute(Bitmap result) {
/*if (pd.isShowing())
pd.dismiss();*/
// studentPic.setImageBitmap(result);
responseImage.processImage(result);
}
public void detach() {
activity = null;
}
public void attach(HomeDynamic activity) {
this.activity = activity;
}
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) {
}
}
#Override
protected Bitmap doInBackground(String... arg0) {
// TODO Auto-generated method stub
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(15000);
conn.setReadTimeout(15000);
conn.setInstanceFollowRedirects(true);
InputStream is = conn.getInputStream();
OutputStream os = new FileOutputStream(f);
CopyStream(is, os);
os.close();
bitmap = decodeFile(f);
return bitmap;
} catch (Exception ex) {
ex.printStackTrace();
return null;
}
}
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 = 64;
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;
}
}

Without showing any code that you did, it is very difficult to figure out where the problem is. If your activity involves so many photos, I suggest using Picasso library which will do excellent job for handling images.

bitmap.copy() throws out of memory error

I am using universal-image-loader library to load images, but when I call copy() on a loaded bitmap file in some cases I get OutOfMemoryError.
Here is my code:
ImageLoader.getInstance().loadImage(path, new ImageLoadingListener() {
#Override
public void onLoadingStarted(String arg0, View arg1) {
// TODO Auto-generated method stub
}
#Override
public void onLoadingFailed(String arg0, View arg1, FailReason arg2) {
// TODO Auto-generated method stub
}
#Override
public void onLoadingComplete(String arg0, View arg1, Bitmap arg2) {
bm = arg2;
}
#Override
public void onLoadingCancelled(String arg0, View arg1) {
// TODO Auto-generated method stub
}
});
Bitmap bm2= bm.copy(Bitmap.Config.ARGB_8888, true); //where the crash happens
I need the second Bitmap not to be mutable so I can draw on it.

First of all try to find a little time to read good official documentation about bitmaps: Displaying Bitmaps Efficiently
It will give you understanding why and when java.lang.OutofMemoryError happens. And how to avoid it.
What about your question: see this article: Android: convert Immutable Bitmap into Mutable
But from API Level 11 only options.inMutable available to load the
file into a mutable bitmap.
So, if we are building application with API level less than 11, then
we have to find some other alternatives.
One alternative is creating another bitmap by copying the source
bitmap. mBitmap = mBitmap.copy(ARGB_8888 ,true);
But the will throw OutOfMemoryException if the source file is big.
Actually incase if we want to edit an original file, then we will face
this issue. We should be able to load at-least image into memory, but
most we can not allocate another copy into memory.
So, we have to save the decoded bytes into some where and clear
existing bitmap, then create a new mutable bitmap and load back the
saved bytes into bitmap again. Even to copy bytes we cannot create
another ByteBuffer inside the memory. In that case need to use
MappedByteBuffer that will allocate bytes inside a disk file.
Following code would explain clearly:
//this is the file going to use temporally to save the bytes.
File file = new File("/mnt/sdcard/sample/temp.txt");
file.getParentFile().mkdirs();
//Open an RandomAccessFile
/*Make sure you have added uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"
into AndroidManifest.xml file*/
RandomAccessFile randomAccessFile = new RandomAccessFile(file, "rw");
// get the width and height of the source bitmap.
int width = bitmap.getWidth();
int height = bitmap.getHeight();
//Copy the byte to the file
//Assume source bitmap loaded using options.inPreferredConfig = Config.ARGB_8888;
FileChannel channel = randomAccessFile.getChannel();
MappedByteBuffer map = channel.map(MapMode.READ_WRITE, 0, width*height*4);
bitmap.copyPixelsToBuffer(map);
//recycle the source bitmap, this will be no longer used.
bitmap.recycle();
//Create a new bitmap to load the bitmap again.
bitmap = Bitmap.createBitmap(width, height, Config.ARGB_8888);
map.position(0);
//load it back from temporary
bitmap.copyPixelsFromBuffer(map);
//close the temporary file and channel , then delete that also
channel.close();
randomAccessFile.close();
And here is sample code.

Be thankful that it happens on your device, and not only on your user's devices.
1) That's something you have to cope with, and react to appropriately. Display error message, or load lower resolution of the bitmap. Your app will run on many kinds of devices, each has different amount of memory.
2) Use important function Bitmap.recycle after each operation which makes your old bitmap redundant. This will immediately free memory for next work without waiting for GC to run, and possible out of memory errors.

You cant do much about the bitmap outofmemory error except ensuring that the bitmap you are copying or displaying is not much large. Fortunately universal imageloader has a feature to compress bitmap by changing the config. So give Bitmap.Config.RGG_565 a try. Its supposed to half the memory footprint of the bitmap. You can also request for large heap size. Another thing you can do is copy the scaled version of the bitmap.

As Illegel Argument said, you need to make sure that the Bitmap is not TOO large. Also, make sure that you are only loading one Bitmap at a time into memory.
You can dynamically scale the bitmap using BitmapFactory
Bitmap b = BitmapFactory.decodeByteArray(imageAsBytes, 0, imageAsBytes.length)
image.setImageBitmap(Bitmap.createScaledBitmap(b, 300, 300, false));

Download this code from the site
http://www.androidhive.info/2012/02/android-custom-listview-with-image-and-text/
extract its ImageLoader , file cache , memory cache classes use them in your bitmap to do things wont create out of memory exception at all and will cache images and increase performance

Use this Code to fullfill your purpose
Make the following classes in your code and in last use imageloader to load url pass it url , imageview and drawable to show incase url is not returning any image
FileCache.java
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(),"LazyList");
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();
}
}
MemoryCache.java
public class MemoryCache {
private Map<String, SoftReference<Bitmap>> cache=Collections.synchronizedMap(new HashMap<String, SoftReference<Bitmap>>());
public Bitmap get(String id){
if(!cache.containsKey(id))
return null;
SoftReference<Bitmap> ref=cache.get(id);
return ref.get();
}
public void put(String id, Bitmap bitmap){
cache.put(id, new SoftReference<Bitmap>(bitmap));
}
public void clear() {
cache.clear();
}
}
Utils.java
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){}
}
}
ImageLoader.java
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.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 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=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();
}
}
call this code where you want to cache or download or manage images
imageLoader.DisplayImage(song.get(CustomizedListView.KEY_THUMB_URL), thumb_image);

how to parse and display a url contents inside a json array?

i have a images inside a jsonarray but like "flag": [
"http://www.simplydecoded.com/wp-content/uploads/2013/02/Telangana2.jpg"
]
but not displaying..
i am using this tutorial for parsing the data
and i sucessfully parsed all data but except images are not coming
i am using this to call images which are in side a json array actually its a url..
JSONArray json_query_flag = c.getJSONArray("flag");
and i followd remaning all fro this question..
it just extention of that not duplicate..
and i am using below for the part for the part of downloading image to bitmap
public class ImageLoader {
MemoryCache memoryCache = new MemoryCache();
FileCache fileCache;
private Map<ImageView, String> imageViews = Collections
.synchronizedMap(new WeakHashMap<ImageView, String>());
ExecutorService executorService;
// Handler to display images in UI thread
Handler handler = new Handler();
public ImageLoader(Context context) {
fileCache = new FileCache(context);
executorService = Executors.newFixedThreadPool(5);
}
final int stub_id = R.drawable.temp;
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);
Bitmap b = decodeFile(f);
if (b != null)
return b;
// Download Images from the Internet
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();
conn.disconnect();
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.
// Recommended Size 512
final int REQUIRED_SIZE = 70;
int width_tmp = o.outWidth, height_tmp = o.outHeight;
int scale = 2;
while (true) {
if (width_tmp / 2 < REQUIRED_SIZE
|| height_tmp / 2 < REQUIRED_SIZE)
break;
width_tmp /= 4;
height_tmp /= 4;
scale *= 4;
}
// 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();
}
}

Try this..
JSONArray json_query_flag = c.getJSONArray("flag");
for(int i=0;i<json_query_flag.length();i++)
{
Log.v("URL"+json_query_flag.getString(i));
}
EDIT
ImageLoader imageLoader=new ImageLoader(activity.this);
and set image as
imageLoader.DisplayImage(URL, imageview);
here imageview is name of that imageview and URl is that string Url
OR
Bitmap bitmap = null;
try {
imageURL = new URL(utl2);
}
catch (MalformedURLException e) {
e.printStackTrace();
}
try {
HttpURLConnection connection = (HttpURLConnection) imageURL
.openConnection();
connection.setDoInput(true);
connection.connect();
InputStream inputStream = connection.getInputStream();
bitmap = BitmapFactory.decodeStream(inputStream);
image_view.setImageBitmap(bitmap);
} catch (IOException e) {
e.printStackTrace();
}

app is slow with images in android

I am doing a app on images to show them in GridView, i am fetching 20 images from server. Resolution of the each image is 720*540.I used JSON parsing to fetch url and used below code to convert into Bitmap in order to set images.
public static Bitmap loadImageFromUrl(String url) {
InputStream inputStream;Bitmap b;
try {
inputStream = (InputStream) new URL(url).getContent();
BitmapFactory.Options bpo= new BitmapFactory.Options();
if(bpo.outWidth>500) {
bpo.inSampleSize=8;
b=BitmapFactory.decodeStream(inputStream, null,bpo );
} else {
bpo.inSampleSize=2;
b=BitmapFactory.decodeStream(inputStream, null,bpo );
}
return b;
} catch (IOException e) {
throw new RuntimeException(e);
}
}
my app is working fine but it is taking too much time to load the images. So that my app became slow. Should i decrease the resolution of images?
how to come out of the issue?

If you are doing a grid view to load 20 images of such resolution, I would suggest the following:
Definitely reduce the size of the images. Unless you are targeting a tablet, you will be fine as most smartphones cannot achieve that resolution with 20 images.
Cache images if you can.
Download the images on a different thread. Store a HashMap would make it easy for you, just put all the imageviews with the image file names or other form of IDs as keys. send message to your Handler when images are downloaded and update the view after it's decoded. You can retrieve your views directly. Just remember to check if they are still in the window. This way the images will show up one after another quickly. I don't think multithreading the images will help, just make sure to use another thread to "push the images" and the main UI thread updates. User experience will be greatly improved then.
Hope this helps.
---some implementations, I don't have the complete code with me right now---
Have a data structure to match the views with data that comes in. very handy here.
private HashMap<String,ImageView> pictures;
When you get the list of image urls, iterate through them:
pictures.put(id,view);
try{
FileInputStream in = openFileInput(id);
Bitmap bitmap = null;
bitmap = BitmapFactory.decodeStream(in, null, null);
view.setImageBitmap(bitmap);
}catch(Exception e){
new Thread(new PictureGetter(this,mHandler,id)).start();
}
(Here the picture getter will simply fetch the image if it is not cached already and cache it)
Code to update the image view:
if(id!=null){
ImageView iv = pictures.get(id);
if(iv!=null){
try{
FileInputStream in = openFileInput(id);
Bitmap bitmap = null;
bitmap = BitmapFactory.decodeStream(in, null, null);
iv.setImageBitmap(bitmap);
}catch(Exception e){
}
}

Picasso library
Solution is instead of using bitmap to load image directly use a awesome Library called Picasso its just super fast i know you really love this you can do this like this
Add picasso jar file to your project (Download picasso jar file here) Use picasso to load the Image like this
Picasso.with(context).load(new File(title)).centerCrop()
.resize(150, 150).error(R.drawable.ic_launcher).into(image);
where title is the image path which you want to load. Crop,resize, error are optional.

I'm guessing that most of the loading time is because of the large amount of images combined with the size of the images.
There are 2 possible solutions:
Resize the images, or lower the quality of the images so that the filesize is below 75kb or so.
Use multi-threading to retrieve multiple images at once. This might not help if the user's connection is really slow, but if you combine this with a small enough filesize it might just help out enough. You might want to determine what the current bandwidth of the device is and base the number of threads you run on that.
For instance: 20 images of 75KB each and an available connection of 200 KB/s = 3 or 4 concurrent threads.
Hope this helps.

I have same problem in my android app. When you decode a bitmap from a big sized image and set as imageBitmap to an image view probably your application will slow and after a few try you'll get an "out of memory exception"
Two of the possible ways you can try to handle this problem:
1- Reduce bitmap size when you decode from file
2- Use an image library.
I prefered second way and used Universal Image Loader. https://github.com/nostra13/Android-Universal-Image-Loader
String url = "file://" + your_file_path
com.nostra13.universalimageloader.core.ImageLoader.getInstance().displayImage(url, ivPicture, options);

public class clothImageLoader {
// the simplest in-memory cache implementation. This should be replaced with
// something like SoftReference or BitmapOptions.inPurgeable(since 1.6)
// public static HashMap<String, Bitmap> cache = new HashMap<String,
// Bitmap>();
private static File cacheDir;
public clothImageLoader(Context context) {
// Make the background thead low priority. This way it will not affect
// the UI performance
photoLoaderThread.setPriority(Thread.NORM_PRIORITY - 1);
// 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(),"LazyList");
cacheDir = new File(ConstValue.MY_ClothBitmap_DIR);
else
cacheDir = context.getCacheDir();
if (!cacheDir.exists())
cacheDir.mkdirs();
}
final int stub_id = R.drawable.icon;
public void DisplayImage(String url, Activity activity, ImageView imageView) {
if (ConstValue.ClothRoomcache.containsKey(url))
imageView.setImageBitmap(ConstValue.ClothRoomcache.get(url));
else {
queuePhoto(url, activity, imageView);
imageView.setImageResource(stub_id);
}
}
private void queuePhoto(String url, Activity activity, ImageView imageView) {
// This ImageView may be used for other images before. So there may be
// some old tasks in the queue. We need to discard them.
photosQueue.Clean(imageView);
PhotoToLoad p = new PhotoToLoad(url, imageView);
synchronized (photosQueue.photosToLoad) {
photosQueue.photosToLoad.push(p);
photosQueue.photosToLoad.notifyAll();
}
// start thread if it's not started yet
if (photoLoaderThread.getState() == Thread.State.NEW)
photoLoaderThread.start();
}
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();
*/
URL url1 = new URL(url);
bitmap = decodeFile(f);
/* Open a connection to that URL. */
URLConnection ucon = url1.openConnection();
/*
* Define InputStreams to read from the URLConnection.
*/
InputStream is = ucon.getInputStream();
// FlushedInputStream a = new FlushedInputStream(is);
BufferedInputStream bis = new BufferedInputStream(is);
/*
* Read bytes to the Buffer until there is nothing more to read(-1).
*/
ByteArrayBuffer baf = new ByteArrayBuffer(5000);
int current = 0;
while ((current = bis.read()) != -1) {
baf.append((byte) current);
}
/* Convert the Bytes read to a String. */
FileOutputStream fos = new FileOutputStream(f);
fos.write(baf.toByteArray());
fos.flush();
fos.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 = ConstValue.bmpSize;
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++;
}
// 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;
}
}
PhotosQueue photosQueue = new PhotosQueue();
public void stopThread() {
photoLoaderThread.interrupt();
}
// stores list of photos to download
class PhotosQueue {
private Stack<PhotoToLoad> photosToLoad = new Stack<PhotoToLoad>();
// removes all instances of this ImageView
public void Clean(ImageView image) {
for (int j = 0; j < photosToLoad.size();) {
if (photosToLoad.get(j).imageView == image)
photosToLoad.remove(j);
else
++j;
}
}
}
class PhotosLoader extends Thread {
public void run() {
try {
while (true) {
// thread waits until there are any images to load in the
// queue
if (photosQueue.photosToLoad.size() == 0)
synchronized (photosQueue.photosToLoad) {
photosQueue.photosToLoad.wait();
}
if (photosQueue.photosToLoad.size() != 0) {
PhotoToLoad photoToLoad;
synchronized (photosQueue.photosToLoad) {
photoToLoad = photosQueue.photosToLoad.pop();
// photoToLoad=photosQueue.photosToLoad.get(0);
// photosQueue.photosToLoad.remove(photoToLoad);
}
Bitmap bmp = getBitmap(photoToLoad.url);
ConstValue.ClothRoomcache.put(photoToLoad.url, bmp);
if (((String) photoToLoad.imageView.getTag()).equals(photoToLoad.url)) {
BitmapDisplayer bd = new BitmapDisplayer(bmp, photoToLoad.imageView);
Activity a = (Activity) photoToLoad.imageView.getContext();
a.runOnUiThread(bd);
}
}
if (Thread.interrupted())
break;
}
} catch (InterruptedException e) {
// allow thread to exit
}
}
}
PhotosLoader photoLoaderThread = new PhotosLoader();
// Used to display bitmap in the UI thread
class BitmapDisplayer implements Runnable {
Bitmap bitmap;
ImageView imageView;
public BitmapDisplayer(Bitmap b, ImageView i) {
bitmap = b;
imageView = i;
}
public void run() {
if (bitmap != null)
imageView.setImageBitmap(bitmap);
else
imageView.setImageResource(stub_id);
}
}
public static void clearCache() {
// clear memory cache
ConstValue.ClothRoomcache.clear();
// clear SD cache
File[] files = cacheDir.listFiles();
for (File f : files)
f.delete();
}
public class FlushedInputStream extends FilterInputStream {
public FlushedInputStream(InputStream inputStream) {
super(inputStream);
}
#Override
public long skip(long n) throws IOException {
long totalBytesSkipped = 0L;
while (totalBytesSkipped < n) {
long bytesSkipped = in.skip(n - totalBytesSkipped);
if (bytesSkipped == 0L) {
int a = read();
if (a < 0) {
break; // we reached EOF
} else {
bytesSkipped = 1; // we read one byte
}
}
totalBytesSkipped += bytesSkipped;
}
return totalBytesSkipped;
}
}
}
when you call the method ,in the gridView getView method:
holder.image.setTag(ChoseInfo.get(position).getLink());
imageLoader.DisplayImage(ChoseInfo.get(position).getLink(), activity, holder.image);
ChoseInfo.get(position).getLink())
Here getLink() is internet link.

OutOfMemoryError: bitmap size exceeds VM budget

Sorry it seems like a repeated question, BUT I think I don't qualify to any of the recommendations already posted.
I've a Gallery of maximum 20 images on my application. After playing a while flinging back and forth I'm getting OutOfMemoryError.
The strange thing is that I don't hold any static references, and I've searched for possible memory leaks I can assure that I've not found one so far.
Anyway, 20 images (PNG of 100KB on average) doesn't be like that much. And I've implemented a view cache, SoftReference holders for the bitmaps, etc.
Is it 20 PNG images of 100KB on average enough to kill my app?? seriously? how can I get rid of this? I've followed this great post also
http://blog.jteam.nl/2009/09/17/exploring-the-world-of-android-part-2/
Any more ideas?
This is the ImageCache:
public class AsyncImageLoader {
private final String TAG = getClass().getSimpleName();
private Context mContext;
private HashMap<String, SoftReference<Bitmap>> mImageCache;
public AsyncImageLoader(Context context) {
mContext = context;
mImageCache = new HashMap<String, SoftReference<Bitmap>>();
}
public Bitmap loadImage(final String identifier, final String imagePath, final ImageCallback imageCallback) {
if (mImageCache.containsKey(imagePath)) {
SoftReference<Bitmap> softReference = mImageCache.get(imagePath);
Bitmap bitmap = softReference.get();
if (bitmap != null) {
Log.i(TAG, "Retrieving image from cache: " + imagePath);
return bitmap;
}
}
final Handler handler = new Handler() {
#Override
public void handleMessage(Message message) {
imageCallback.imageLoaded((Bitmap) message.obj, imagePath, identifier);
}
};
new Thread() {
#Override
public void run() {
Bitmap bitmap = loadImageFromPath(imagePath);
mImageCache.put(imagePath, new SoftReference<Bitmap>(bitmap));
Message message = handler.obtainMessage(0, bitmap);
handler.sendMessage(message);
}
}.start();
return null;
}
public Bitmap loadImageFromPath(String path) {
if(!GeneralUtilities.isEmpty(path)) {
Log.i(TAG, "Loading image: " + path);
InputStream imageInputStream = null;
try {
final AssetManager assetManager = mContext.getResources().getAssets();
imageInputStream = assetManager.open(path);
Bitmap bitmap = GeneralUtilities.decodeFile(imageInputStream);
imageInputStream.close();
return bitmap;
} catch (final IOException e) {
Log.e(TAG, e.getMessage());
}
}
return null;
}
public interface ImageCallback {
public void imageLoaded(Bitmap imageBitmap, String imagePath, String identifier);
}
}
and the method GeneralUtilities.decodeFile is:
public static Bitmap decodeFile(InputStream is){
//Decode image size
BitmapFactory.Options o = new BitmapFactory.Options();
o.inJustDecodeBounds = true;
BitmapFactory.decodeStream(is, null, o);
//The new size we want to scale to
final int REQUIRED_SIZE=140;
//Find the correct scale value. It should be the power of 2.
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(is, null, o2);
}
And in the getView of the ArrayAdapter I've something like this:
final ImageView itemImage = cache.getHistoryImage();
//final ImageView itemFrame = cache.getFrame();
String filename = item.getFilename().trim();
itemImage.setTag("front_" + filename);
Bitmap cachedImage = mAsyncImageLoader.loadImage("front_" + filename, filename, new ImageCallback() {
public void imageLoaded(Bitmap imageBitmap, String imagePath, String identifier) {
ImageView imageViewByTag = (ImageView) mGallery.findViewWithTag(identifier);
if (imageViewByTag != null) {
imageViewByTag.setImageBitmap(imageBitmap);
}
}
});
itemImage.setImageBitmap(cachedImage);

There seems to be a bug in the Android framework, although Google seems to deny it.
Did you read through issue 8488?
http://code.google.com/p/android/issues/detail?id=8488
I am not sure if this applies to your code - but you might try the recommendations before setting/updating the image on the ImageView.
Basically, it boils down to calling Bitmap.recycle(), nulling references (probably irrellevant in your case) and explicitly calling calling System.gc().
The garbage collector seems to run asynchronously and a new might fail even though memory could be freed.