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Re: [android-developers] Lazy Loading of images in the list view
I was able to resolve the issue, just made simple tweaks like removing the
drawableMap we just need the imageCache.
On Sat, Apr 10, 2010 at 10:51 AM, Prajakta Shitole <prajakta28@gmail.com>wrote:
> Forgot to paste my code:-
>
> class IconicAdapter extends ArrayAdapter {
> Activity context;
> Context context2;
> HashMap<String,String> ret = new HashMap<String,String>();
> AsyncLoader async;// = new AsyncLoader();
> private ListView listView;
> HashMap<String,Bitmap> bit = new HashMap<String,Bitmap>();
>
>
> IconicAdapter(Activity context) {
> super(context, R.layout.exclusive, items);
> this.context=context;
> async = new AsyncLoader();
> }
>
> public View getView(final int position, View convertView,
> ViewGroup parent) {
> View row_inflated = View.inflate(context, R.layout.exclusive,null);
> wrapper = new ViewWrapper(row_inflated);
> row_inflated.setTag(wrapper);
>
> wrapper.getSongName().setText(items[position]);
> wrapper.getSingerName().setText(singer_name[position]);
> final ImageView imgview = wrapper.getIcon();
> imgview.setTag(myRemoteImages[position]);
> Bitmap cachedImage = async.loadDrawable(myRemoteImages[position], new
> ImageCallback() {
> public void imageLoaded(Bitmap imageBitmap, String imageUrl) {
> imgview.setImageBitmap(imageBitmap);
> notifyDataSetChanged();
> }
> });
> if(cachedImage!=null)
> imgview.setImageBitmap(cachedImage);
> return(row_inflated);
> }
> }
>
>
> ======================================================================
> AsynLoader is as below:-
>
> public class AsyncLoader{
> HashMap<String,Bitmap> bit = new HashMap<String,Bitmap>();
> private HashMap<String, SoftReference<Bitmap>> imageCache;
> private HashMap<String, SoftReference<Bitmap>> drawableMap;
> public AsyncLoader() {
> drawableMap = new HashMap<String, SoftReference<Bitmap>>();
> imageCache = new HashMap<String, SoftReference<Bitmap>>();
> }
> public Bitmap loadDrawable(final String imageUrl, final ImageCallback
> imageCallback) {
> if (drawableMap.containsKey(imageUrl)) {
> SoftReference<Bitmap> softReference = imageCache.get(imageUrl);
> Bitmap drawable = softReference.get();
> if (drawable != null) {
> return drawable;
> }
> }
> final Handler handler = new Handler() {
> @Override
> public void handleMessage(Message message) {
> imageCallback.imageLoaded((Bitmap) message.obj, imageUrl);
> }
> };
> new Thread() {
> @Override
> public void run() {
> Bitmap bitMap = loadImageFromUrl(imageUrl);
> imageCache.put(imageUrl, new
> SoftReference<Bitmap>(bitMap));
> Message message = handler.obtainMessage(0, bitMap);
> handler.sendMessage(message);
> }
> }.start();
> return null;
> }
>
> public static Bitmap loadImageFromUrl(String url){
>
>
> URL aURL;
> Bitmap bitmap=null;//=this.bm;
> try {
> aURL = new URL(url);
> URLConnection conn;
> conn = aURL.openConnection();
> conn.connect();
> InputStream is= conn.getInputStream();
> BufferedInputStream bis = new BufferedInputStream(is);
> bitmap = BitmapFactory.decodeStream(bis);
> // bitMap.put(p,bm);
> bis.close();
> is.close();
>
>
> } catch (MalformedURLException e) {
> e.printStackTrace();
> } catch (IOException e) {
> e.printStackTrace();
> }
> return bitmap;
> }
>
> public interface ImageCallback {
> public void imageLoaded(Bitmap imageBitmap, String imageUrl);
> }
> }
>
>
> Thanks,
> Prajakta
>
>
>
> On Sat, Apr 10, 2010 at 10:21 AM, praj <prajakta28@gmail.com> wrote:
>
>> Hi,
>>
>> I was trying to implement the lazy loading of images in the list view.
>> For implementing this i was referring to post by Tom van Zummeren.
>> (http://blog.jteam.nl/2009/09/17/exploring-the-world-of-android-
>> part-2/<http://blog.jteam.nl/2009/09/17/exploring-the-world-of-android-part-2/>),
>> but my images keep on changing in the list. Please can
>> anyone let me know if they were able to get this working properly
>> without having the images drawn again and again or let me know if I
>> have missed on anything or doing something wrong.
>>
>> Thanks,
>> Prajakta
>>
>> –
>> You received this message because you are subscribed to the Google
>> Groups "Android Developers" group.
>> To post to this group, send email to android-developers@googlegroups.com
>> To unsubscribe from this group, send email to
>> android-developers+unsubscribe@googlegroups.com<android-developers%2Bunsubscribe@googlegroups.com>
>> For more options, visit this group at
>> http://groups.google.com/group/android-developers?hl=en
>>
>> To unsubscribe, reply using "remove me" as the subject.
>>
>
>
–
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To post to this group, send email to android-developers@googlegroups.com
To unsubscribe from this group, send email to
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For more options, visit this group at
http://groups.google.com/group/android-developers?hl=enI was able to resolve the issue, just made simple tweaks like removing the drawableMap we just need the imageCache.
On Sat, Apr 10, 2010 at 10:51 AM, Prajakta Shitole <prajakta28@gmail.com> wrote:
Forgot to paste my code:-
class IconicAdapter extends ArrayAdapter {Activity context;Context context2;HashMap<String,String> ret = new HashMap<String,String>();AsyncLoader async;// = new AsyncLoader();private ListView listView;HashMap<String,Bitmap> bit = new HashMap<String,Bitmap>();IconicAdapter(Activity context) {super(context, R.layout.exclusive, items);this.context=context;async = new AsyncLoader();}public View getView(final int position, View convertView,ViewGroup parent) {View row_inflated = View.inflate(context, R.layout.exclusive,null);wrapper = new ViewWrapper(row_inflated);row_inflated.setTag(wrapper);wrapper.getSongName().setText(items[position]);wrapper.getSingerName().setText(singer_name[position]);final ImageView imgview = wrapper.getIcon();imgview.setTag(myRemoteImages[position]);Bitmap cachedImage = async.loadDrawable(myRemoteImages[position], new ImageCallback() {public void imageLoaded(Bitmap imageBitmap, String imageUrl) {imgview.setImageBitmap(imageBitmap);notifyDataSetChanged();}});if(cachedImage!=null)imgview.setImageBitmap(cachedImage);return(row_inflated);}}======================================================================AsynLoader is as below:-public class AsyncLoader{HashMap<String,Bitmap> bit = new HashMap<String,Bitmap>();private HashMap<String, SoftReference<Bitmap>> imageCache;private HashMap<String, SoftReference<Bitmap>> drawableMap;public AsyncLoader() {drawableMap = new HashMap<String, SoftReference<Bitmap>>();imageCache = new HashMap<String, SoftReference<Bitmap>>();}public Bitmap loadDrawable(final String imageUrl, final ImageCallback imageCallback) {if (drawableMap.containsKey(imageUrl)) {SoftReference<Bitmap> softReference = imageCache.get(imageUrl);Bitmap drawable = softReference.get();if (drawable != null) {return drawable;}}final Handler handler = new Handler() {@Overridepublic void handleMessage(Message message) {imageCallback.imageLoaded((Bitmap) message.obj, imageUrl);}};new Thread() {@Overridepublic void run() {Bitmap bitMap = loadImageFromUrl(imageUrl);imageCache.put(imageUrl, new SoftReference<Bitmap>(bitMap));Message message = handler.obtainMessage(0, bitMap);handler.sendMessage(message);}}.start();return null;}public static Bitmap loadImageFromUrl(String url){URL aURL;Bitmap bitmap=null;//=this.bm;try {aURL = new URL(url);URLConnection conn;conn = aURL.openConnection();conn.connect();InputStream is= conn.getInputStream();BufferedInputStream bis = new BufferedInputStream(is);bitmap = BitmapFactory.decodeStream(bis);// bitMap.put(p,bm);bis.close();is.close();} catch (MalformedURLException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}return bitmap;}public interface ImageCallback {public void imageLoaded(Bitmap imageBitmap, String imageUrl);}}Thanks,PrajaktaOn Sat, Apr 10, 2010 at 10:21 AM, praj <prajakta28@gmail.com> wrote:
Hi,
I was trying to implement the lazy loading of images in the list view.
For implementing this i was referring to post by Tom van Zummeren.
(http://blog.jteam.nl/2009/09/17/exploring-the-world-of-android-
part-2/), but my images keep on changing in the list. Please can
anyone let me know if they were able to get this working properly
without having the images drawn again and again or let me know if I
have missed on anything or doing something wrong.Thanks,
Prajakta–
You received this message because you are subscribed to the Google
Groups "Android Developers" group.
To post to this group, send email to android-developers@googlegroups.com
To unsubscribe from this group, send email to
android-developers+unsubscribe@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/android-developers?hl=enTo unsubscribe, reply using "remove me" as the subject.
–
You received this message because you are subscribed to the Google
Groups "Android Developers" group.
To post to this group, send email to android-developers@googlegroups.com
To unsubscribe from this group, send email to
android-developers+unsubscribe@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/android-developers?hl=en
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