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Ich habe GridView mit Bildansichten, die Bild Miniaturbilder der Galerie geladen werden. Wenn ich diese Thumbnails aus einer Klasse lade, in der ich eine Methode mit image id und imageview aufruft, setzt die Methode die Bitmap auf passed imageview. Bis jetzt funktioniert es perfekt, aber der Thread wird angehalten, wenn wir die Rasteransicht verschieben.Android Gridview Bilder Caching, auf Bildlauf Bilder werden wiederholt, bevor ersetzt
Mein Problem hier ist es pausiert beim Scrollen, aber die Bilder werden in der Gridview beim Scrollen von oben nach unten wiederholt. Ich bin nicht in der Lage, das genaue Problem herauszufinden. helfen Sie mir. Vielen Dank!
Hier ist, wie ich die Einstellung der Pause:
imagegrid.setOnScrollListener(new AbsListView.OnScrollListener() {
@Override
public void onScrollStateChanged(AbsListView absListView, int scrollState) {
// Pause fetcher to ensure smoother scrolling when flinging
if (scrollState == AbsListView.OnScrollListener.SCROLL_STATE_FLING) {
bitmapFromId.setPauseWork(true);
} else {
bitmapFromId.setPauseWork(false);
}
}
@Override
public void onScroll(AbsListView absListView, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
}
});
Hier ist in grdiview Adapter meine get Ansicht:
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
holder = new ViewHolder();
convertView = mInflater.inflate(R.layout.galleryitem, null);
holder.imageview = (ImageView) convertView.findViewById(R.id.thumbImage);
holder.checkbox = (CheckBox) convertView.findViewById(R.id.itemCheckBox);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
ImageItem item = images.get(position);
holder.checkbox.setId(position);
holder.imageview.setId(position);
holder.checkbox.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
CheckBox cb = (CheckBox) v;
int id = cb.getId();
if (images.get(id).selection) {
cb.setChecked(false);
images.get(id).selection = false;
} else {
cb.setChecked(true);
images.get(id).selection = true;
}
}
});
holder.imageview.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
int id = v.getId();
ImageItem item = images.get(id);
Intent intent = new Intent();
intent.setAction(Intent.ACTION_VIEW);
final String[] columns = { MediaStore.Images.Media.DATA };
Cursor imagecursor = getContentResolver().query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
columns, MediaStore.Images.Media._ID + " = " + item.id, null, MediaStore.Images.Media._ID);
if (imagecursor != null && imagecursor.getCount() > 0) {
imagecursor.moveToPosition(0);
String path = imagecursor.getString(imagecursor
.getColumnIndexOrThrow(MediaStore.Images.Media.DATA));
File file = new File(path);
imagecursor.close();
intent.setDataAndType(Uri.fromFile(file), "image/*");
startActivityForResult(intent, VIEW_IMAGE);
}
}
});
holder.imageview.setLayoutParams(mImageViewLayoutParams);
// Check the height matches our calculated column width
if (holder.imageview.getLayoutParams().height != mItemHeight) {
holder.imageview.setLayoutParams(mImageViewLayoutParams);
}
bitmapFromId.DisplayImage(item.id, holder.imageview);
// holder.imageview.setImageBitmap(item.img);
holder.checkbox.setChecked(item.selection);
return convertView;
}
Meine Bitmap-Loader-Klasse:
public class BitmapFromId {
MemoryCache memoryCache = new MemoryCache();
FileCache fileCache;
private Map<ImageView, String> imageViews = Collections.synchronizedMap(new WeakHashMap<ImageView, String>());
ExecutorService executorService;
Context context;
Handler handler = new Handler();// handler to display images in UI thread
Resources mResources;
private static final int FADE_IN_TIME = 400;
private final Object mPauseLock = new Object();
private boolean mPaused = false;
public BitmapFromId(Context context) {
fileCache = new FileCache(context);
executorService = Executors.newFixedThreadPool(5);
this.context = context;
mResources = context.getResources();
}
public void DisplayImage(long id, ImageView imageView) {
Bitmap bitmap = null;
String _id = String.valueOf(id);
imageViews.put(imageView, _id);
bitmap = memoryCache.get(_id);
if (bitmap != null)
imageView.setImageBitmap(bitmap);
else {
queuePhoto(_id, imageView);
imageView.setBackgroundResource(R.drawable.empty_photo);
}
}
private void queuePhoto(String id, ImageView imageView) {
PhotoToLoad p = new PhotoToLoad(id, imageView);
executorService.submit(new PhotosLoader(p));
}
// decodes image
private Bitmap getImageFromId(String id) {
Bitmap bitmap;
long _id = Long.parseLong(id);
final String[] columns = { MediaStore.Images.Media.DATA };
final String orderBy = MediaStore.Images.Media._ID;
Cursor imagecursor = context.getContentResolver().query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, columns,
MediaStore.Images.Media._ID + " = " + _id + "", null, orderBy);
int count = imagecursor.getCount();
for (int i = 0; i < count; i++) {
imagecursor.moveToPosition(i);
bitmap = MediaStore.Images.Thumbnails.getThumbnail(context.getContentResolver(), _id,
MediaStore.Images.Thumbnails.MICRO_KIND, null);
return bitmap;
}
imagecursor.close();
return null;
}
// Task for the queue
private class PhotoToLoad {
public String id;
public ImageView imageView;
public PhotoToLoad(String _i, ImageView i) {
id = _i;
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 = getImageFromId(photoToLoad.id);
memoryCache.put(photoToLoad.id, bmp);
if (imageViewReused(photoToLoad))
return;
BitmapDisplayer bd = new BitmapDisplayer(bmp, photoToLoad);
handler.post(bd);
synchronized (mPauseLock) {
while (mPaused) {
try {
mPauseLock.wait();
} catch (InterruptedException e) {
}
}
}
} catch (Throwable th) {
th.printStackTrace();
}
}
}
boolean imageViewReused(PhotoToLoad photoToLoad) {
String tag = imageViews.get(photoToLoad.imageView);
if (tag == null || !tag.equals(photoToLoad.id))
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) {
// Load the image fetched:
final TransitionDrawable td = new TransitionDrawable(new Drawable[] {
new ColorDrawable(android.R.color.transparent), new BitmapDrawable(mResources, bitmap) });
photoToLoad.imageView.setImageDrawable(td);
td.startTransition(FADE_IN_TIME);
} else
photoToLoad.imageView.setImageDrawable(null);
}
}
public void clearCache() {
memoryCache.clear();
fileCache.clear();
}
public void setPauseWork(boolean pauseWork) {
if (pauseWork) {
synchronized (mPauseLock) {
mPaused = true;
}
} else {
synchronized (mPauseLock) {
mPaused = false;
mPauseLock.notifyAll();
}
}
}
}
https://github.com/nostra13/Android-Universal-Image-Loader –