ImageLoader クラスを使用して URL から画像を読み込み、リスト ビューに表示しています。しかし、この ImageLoader はエミュレーターにイメージをロードしています。実際のデバイスでアプリを実行すると、イメージはロードされません (デフォルトのイメージを表示するだけです)。
ImageLoader クラスを実際のデバイスで動作させるにはどうすればよいか教えてください。
ImageLoader クラス:
public class ImageLoader {
MemoryCache memoryCache = new MemoryCache();
FileCache fileCache;
private Map<ImageView, String> imageViews = Collections
.synchronizedMap(new WeakHashMap<ImageView, String>());
ExecutorService executorService;
// Handler to display images in UI thread
Handler handler = new Handler();
public ImageLoader(Context context) {
fileCache = new FileCache(context);
executorService = Executors.newFixedThreadPool(5);
}
final int stub_id = R.drawable.products;
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);
Bitmap b = decodeFile(f);
if (b != null)
return b;
// Download Images from the Internet
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();
conn.disconnect();
bitmap = decodeFile(f);
return bitmap;
} catch (Throwable ex) {
ex.printStackTrace();
if (ex instanceof OutOfMemoryError)
memoryCache.clear();
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;
FileInputStream stream1 = new FileInputStream(f);
BitmapFactory.decodeStream(stream1, null, o);
stream1.close();
// Find the correct scale value. It should be the power of 2.
// Recommended Size 512
final int REQUIRED_SIZE = 70;
int width_tmp = o.outWidth, height_tmp = o.outHeight;
int scale = 1;
while (true) {
if (width_tmp / 2 < REQUIRED_SIZE
|| height_tmp / 2 < REQUIRED_SIZE)
break;
width_tmp /= 2;
height_tmp /= 2;
scale *= 2;
}
// Decode with inSampleSize
BitmapFactory.Options o2 = new BitmapFactory.Options();
o2.inSampleSize = scale;
FileInputStream stream2 = new FileInputStream(f);
Bitmap bitmap = BitmapFactory.decodeStream(stream2, null, o2);
stream2.close();
return bitmap;
} catch (FileNotFoundException e) {
} catch (IOException e) {
e.printStackTrace();
}
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() {
try {
if (imageViewReused(photoToLoad))
return;
Bitmap bmp = getBitmap(photoToLoad.url);
memoryCache.put(photoToLoad.url, bmp);
if (imageViewReused(photoToLoad))
return;
BitmapDisplayer bd = new BitmapDisplayer(bmp, photoToLoad);
handler.post(bd);
} catch (Throwable th) {
th.printStackTrace();
}
}
}
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();
}
}
私の GalleryTab クラス:--
public class GalleryTab extends Fragment {
GridView gridview;
ProgressDialog mProgressDialog;
GridViewAdapter adapter;
public List<GalleryList> phonearraylist = null;
View view;
private WeakReference<RemoteDataTask> asyncTaskWeakRef;
public static Fragment newInstance(Context context) {
GalleryTab f = new GalleryTab();
return f;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
view = inflater.inflate(R.layout.activity_gallery_tab, null);
gridview = (GridView) view.findViewById(R.id.gridview);
setRetainInstance(true);
startNewAsyncTask();
// new RemoteDataTask(this).execute();
return view;
}
// RemoteDataTask AsyncTask
private class RemoteDataTask extends AsyncTask<Void, Void, Void> {
private WeakReference<GalleryTab> fragmentWeakRef;
private RemoteDataTask(GalleryTab gallerytab) {
this.fragmentWeakRef = new WeakReference<GalleryTab>(gallerytab);
}
@Override
protected void onPreExecute() {
super.onPreExecute();
mProgressDialog = new ProgressDialog(getActivity());
mProgressDialog.setTitle("Gallery");
mProgressDialog.setMessage("Loading...");
mProgressDialog.setIndeterminate(false);
mProgressDialog.show();
}
@Override
protected Void doInBackground(Void... params) {
// Create the array
phonearraylist = new ArrayList<GalleryList>();
try {
for (int i = 0; i <= 6; i++) {
GalleryList map = new GalleryList();
map.setGallery("http://oi39.tinypic.com/21oydxs.jpg");
// System.out.println("PRINT!!!!-- "+ i);
phonearraylist.add(map);
}
} catch (ParseException e) {
Log.e("Error", e.getMessage());
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
// if (this.fragmentWeakRef.get() != null) {
adapter = new GridViewAdapter(getActivity(), phonearraylist);
// System.out.println("PRINT SIZE -- "+ phonearraylist.size());
gridview.setAdapter(adapter);
mProgressDialog.dismiss();
// }
}
}
private void startNewAsyncTask() {
RemoteDataTask asyncTask = new RemoteDataTask(this);
this.asyncTaskWeakRef = new WeakReference<RemoteDataTask>(asyncTask);
asyncTask.execute();
}
}
私の GridViewAdapter クラス:-
public class GridViewAdapter extends BaseAdapter {
// Declare Variables
Context context;
LayoutInflater inflater;
ImageLoader imageLoader;
private List<GalleryList> galleryArraylist = null;
private ArrayList<GalleryList> arraylist;
public GridViewAdapter(Context context, List<GalleryList> phonearraylist) {
this.context = context;
this.galleryArraylist = phonearraylist;
inflater = LayoutInflater.from(context);
this.arraylist = new ArrayList<GalleryList>();
this.arraylist.addAll(phonearraylist);
imageLoader = new ImageLoader(context);
}
public class ViewHolder {
ImageView phone;
}
@Override
public int getCount() {
return galleryArraylist.size();
}
@Override
public Object getItem(int position) {
return galleryArraylist.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
public View getView(final int position, View view, ViewGroup parent) {
final ViewHolder holder;
if (view == null) {
holder = new ViewHolder();
view = inflater.inflate(R.layout.gridview_item, null);
// Locate the ImageView in gridview_item.xml
holder.phone = (ImageView) view.findViewById(R.id.phone);
view.setTag(holder);
} else {
holder = (ViewHolder) view.getTag();
}
// Set the results into ImageView
imageLoader.DisplayImage(galleryArraylist.get(position).getGallery(),
holder.phone);
// Listen for GridView Item Click
view.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
// Send single item click data to SingleItemView Class
Intent intent = new Intent(context, SingleItemView.class);
// Pass all data phone
intent.putExtra("gallery",
(galleryArraylist.get(position).getGallery()));
// Start SingleItemView Class
context.startActivity(intent);
}
});
return view;
}
}