Android image caching

And now the punchline: use the system cache.

URL url = new URL(strUrl);URLConnection connection = url.openConnection();connection.setUseCaches(true);Object response = connection.getContent();if (response instanceof Bitmap) {  Bitmap bitmap = (Bitmap)response;} 

Provides both memory and flash-rom cache, shared with the browser.

grr. I wish somebody had told ME that before i wrote my own cache manager.

Regarding the elegant connection.setUseCaches solution above: sadly, it won't work without some additional effort. You will need to install a ResponseCache using ResponseCache.setDefault. Otherwise, HttpURLConnection will silently ignore the setUseCaches(true) bit.

See the comments at the top of FileResponseCache.java for details:

http://libs-for-android.googlecode.com/svn/reference/com/google/android/filecache/FileResponseCache.html

(I'd post this in a comment, but I apparently don't have enough SO karma.)

Convert them into Bitmaps and then either store them in a Collection(HashMap,List etc.) or you can write them on the SDcard.

When storing them in application space using the first approach, you might want to wrap them around a java.lang.ref.SoftReference specifically if their numbers is large (so that they are garbage collected during crisis). This could ensue a Reload though.

HashMap<String,SoftReference<Bitmap>> imageCache =        new HashMap<String,SoftReference<Bitmap>>();

writing them on SDcard will not require a Reload; just a user-permission.