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    <p>// File cache class</p> <pre><code>package com.imageloader; 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(),"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(); } } </code></pre> <p>// ImageLoader class</p> <pre><code>package com.imageloader; 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); } 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 (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; } 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>// MemoryCache Class</p> <pre><code>package com.imageloader; 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>// Utils class</p> <pre><code>package com.imageloader; 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> <p>// Getting images from url in BaseAdapter for listview and GridView</p> <pre><code>package com.inflater; import java.util.ArrayList; import android.content.Context; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.ImageView; import android.widget.TextView; import com.globaldata.Utilities; import com.imageloader.ImageLoader; public class MyAdapter extends BaseAdapter { private Context mContext; private ImageLoader mImageLoader; private ArrayList&lt;Model&gt; mArrayList = new ArrayList&lt;Model&gt;(); private LayoutInflater mLayoutInflater; public VideoArrangeAdapter(Context ctx, ArrayList&lt;Model&gt; mData) { this.mContext = ctx; this.mArrayList = mData; this.mImageLoader = new ImageLoader(this.mContext); this.mLayoutInflater = (LayoutInflater) this.mContext .getSystemService(Context.LAYOUT_INFLATER_SERVICE); } @Override public int getCount() { return mArrayList.size(); } @Override public Object getItem(int position) { return mArrayList.get(position); } @Override public long getItemId(int arg0) { return arg0; } private class ViewHolder { private ImageView iv_image; private TextView textview_title; } @Override public View getView(int position, View convertView, ViewGroup parent) { ViewHolder holder = null; if (convertView == null) { holder = new ViewHolder(); convertView = mLayoutInflater.inflate(R.layout.item_of_listview, null); holder.iv_image = (ImageView) convertView .findViewById(R.id.iv_image); holder.textview_title = (TextView) convertView .findViewById(R.id.textview_title); convertView.setTag(holder); } else { holder = (ViewHolder) convertView.getTag(); } holder.textview_title.setText(mArrayList.get(position).get_title()); mImageLoader.DisplayImage(mArrayList.get(position).get_thumb(), holder.iv_image); notifyDataSetChanged(); return convertView; } } </code></pre>
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    1. POLazy Loading (Image + Text) for Linear Layouts
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    1. This table or related slice is empty.
    1. USHiren Patel
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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