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    <p>Open your main activity and type the following code. Whenever you want to show an image from url just call the following code:</p> <pre><code> ImageLoader imgLoader = new ImageLoader(getApplicationContext()); imgLoader.DisplayImage(image_url, loader, image); </code></pre> <p>// image_url - is image url path</p> <p>// loader - loader image, will be shown before loading image</p> <p>// image - is ImageView</p> <p><strong>ImageLoader.java</strong></p> <pre><code>import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.InputStream; import java.io.OutputStream; import java.net.HttpURLConnection; import java.net.URL; import java.util.Collections; import java.util.Map; import java.util.WeakHashMap; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import android.app.Activity; import android.content.Context; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.widget.ImageView; public class ImageLoader { MemoryCache memoryCache=new MemoryCache(); FileCache fileCache; private Map&lt;ImageView, String&gt; imageViews=Collections.synchronizedMap(new WeakHashMap&lt;ImageView, String&gt;()); ExecutorService executorService; public ImageLoader(Context context){ fileCache=new FileCache(context); executorService=Executors.newFixedThreadPool(5); } int stub_id = R.drawable.ic_launcher; public void DisplayImage(String url, int loader, ImageView imageView) { stub_id = loader; imageViews.put(imageView, url); Bitmap bitmap=memoryCache.get(url); if(bitmap!=null) imageView.setImageBitmap(bitmap); else { queuePhoto(url, imageView); imageView.setImageResource(loader); } } 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&lt;REQUIRED_SIZE || height_tmp/2&lt;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(); } } </code></pre> <p><strong>FileCache.java</strong></p> <pre><code>import java.io.File; import android.content.Context; 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(),"TempImages"); else cacheDir=context.getCacheDir(); if(!cacheDir.exists()) cacheDir.mkdirs(); } public File getFile(String url){ String filename=String.valueOf(url.hashCode()); 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(); } } </code></pre> <p><strong>MemoryCache.java</strong></p> <pre><code>import java.lang.ref.SoftReference; import java.util.Collections; import java.util.HashMap; import java.util.Map; import android.graphics.Bitmap; public class MemoryCache { private Map&lt;String, SoftReference&lt;Bitmap&gt;&gt; cache=Collections.synchronizedMap(new HashMap&lt;String, SoftReference&lt;Bitmap&gt;&gt;()); public Bitmap get(String id){ if(!cache.containsKey(id)) return null; SoftReference&lt;Bitmap&gt; ref=cache.get(id); return ref.get(); } public void put(String id, Bitmap bitmap){ cache.put(id, new SoftReference&lt;Bitmap&gt;(bitmap)); } public void clear() { cache.clear(); } } </code></pre> <p><strong>Utils.java</strong></p> <pre><code>import java.io.InputStream; import java.io.OutputStream; 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){} } } </code></pre>
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    1. POhow to display an image from JSON Object
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    1. COYour code works fine....we use only a single URL image in ur code.... but my question was we want to show the images from JSON Objects...
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    2. CO@NaveenR As far as I remember, I used this same ImageLoader class to load multiple images from a json and view in listview in a project. Modifying it a little bit will do the job. If I can get the exact code, I will post it.
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    3. COk fida...Thank u !!
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