i am trying lazy loading with LruCache as shown here : Example using Androids lrucache.
public class TCImageLoader implements ComponentCallbacks2 {
private TCLruCache cache;
Context cv;
public TCImageLoader(Context context) {
ActivityManager am = (ActivityManager) context.getSystemService(
Context.ACTIVITY_SERVICE);
int maxKb = am.getMemoryClass() * 1024;
int limitKb = maxKb / 8; // 1/8th of total ram
cache = new TCLruCache(limitKb);
cv = context;
}
public void display(String url, ImageView imageview, int defaultresource) {
imageview.setImageResource(defaultresource);
Bitmap image = cache.get(url);
if (image != null) {
imageview.setImageBitmap(image);
}
else {
new SetImageTask(imageview).execute(url);
}
}
private class TCLruCache extends LruCache<String, Bitmap> {
public TCLruCache(int maxSize) {
super(maxSize);
}
@Override
protected int sizeOf(String key, Bitmap value) {
int kbOfBitmap = value.getByteCount() / 1024;
return kbOfBitmap;
}
}
private class SetImageTask extends AsyncTask<String, Void, Integer> {
private ImageView imageview;
private Bitmap bmp;
public SetImageTask(ImageView imageview) {
this.imageview = imageview;
}
@Override
protected Integer doInBackground(String... params) {
String url = params[0];
try {
//bmp = BitmapFactory.decodeResource(cv.getResources(), url);
bmp = getBitmapFromURL(url);
if (bmp != null) {
cache.put(url, bmp);
}
else {
return 0;
}
} catch (Exception e) {
e.printStackTrace();
return 0;
}
return 1;
}
@Override
protected void onPostExecute(Integer result) {
if (result == 1) {
imageview.setImageBitmap(bmp);
}
//super.onPostExecute(result);
}
private Bitmap getBitmapFromURL(String src) {
try {
URL url = new URL(src);
HttpURLConnection connection
= (HttpURLConnection) url.openConnection();
connection.setDoInput(true);
connection.connect();
InputStream input = connection.getInputStream();
Bitmap myBitmap = BitmapFactory.decodeStream(input);
return myBitmap;
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
}
@Override
public void onConfigurationChanged(Configuration newConfig) {
}
@Override
public void onLowMemory() {
}
@Override
public void onTrimMemory(int level) {
/* if (level >= TRIM_MEMORY_MODERATE) {
cache.evictAll();
}
else if (level >= TRIM_MEMORY_BACKGROUND) {
cache.trimToSize(cache.size() / 2);
}*/
}
}
the TCimageloader is as shown in above code. my getview is as shown below :
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView;
if (convertView == null) {
// if it's not recycled, initialize some attributes
imageView = new ImageView(mContext);
imageView.setLayoutParams(new GridView.LayoutParams(200, 200));
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
// imageView.setPadding(10,10,10,10);
} else {
imageView = (ImageView) convertView;
}
imagloader = new TCImageLoader(mContext);
imagloader.display(mThumbIds[position], imageView, R.drawable.ic_launcher);
//Picasso.with(mContext).load(mThumbIds[position]).placeholder(R.drawable.ic_launcher).into(imageView);
imageView.setImageResource(R.drawable.ic_launcher);
return imageView;
}
but the problem i am facing is that when I scroll fast the getView
has already been called and display method is already called. so the image views keep changing until the last called is implemented.
i am trying to make a custom gallery and this will also help me in downloading images from urls. I will have to use same method . will just have to change the file address to url address