I tried to make a custom Adapter and I made it functionall maybe not the best way and may be not the intelligentes Way so I ask here what I can do to make this a little more efficient
public class MovieDataAdapter extends BaseAdapter implements FetchImage.AsyncResponse {
private Context mContext;
public MovieDataAdapter(Context context) {
mContext = context;
}
#Override
public int getCount() { // get coutn Method
SQLiteDatabase db = new MvDBHelper(mContext).getReadableDatabase();
Cursor cur = db.query(MovieContract.MovieEntry.TABLE_NAME, null, null, null, null, null, null);
return cur.getCount();
}
#Override
public Object getItem(int position) {
return null;
}//Not needed at the moment
#Override
public long getItemId(int position) {
return 0;
}// Not needed at the moment
#Override
public View getView(int position, View convertView, ViewGroup parent) {
final ImageView imageview;
if (convertView != null) {
imageview = (ImageView) convertView; //if used view just use ist again
} else {//if new view set the fitting parameters
imageview = new ImageView(mContext);
imageview.setLayoutParams(new GridView.LayoutParams(getw('w'), getw('h')));
imageview.setScaleType(ImageView.ScaleType.FIT_XY);
}
SQLiteDatabase picturedb = new MvDBHelper(mContext).getReadableDatabase();
Cursor cur = picturedb.query(MovieContract.MovieEntry.TABLE_NAME,
null, null, null, null, null, null
);//get the entries from the db
if (cur != null && cur.moveToFirst()) {
cur.moveToPosition(position); // move to the appropriate position
//defining nessesary Variables
int index_PosterPath = cur.getColumnIndex(MovieContract.MovieEntry.COL_POSTERPATH);
int index_FilePath = cur.getColumnIndex(MovieContract.MovieEntry.COL_FILE);
int index_ortTitel = cur.getColumnIndex(MovieContract.MovieEntry.COL_ORTITEL);
final String Filename = cur.getString(index_ortTitel) + ".jpg";
final String selection = MovieContract.MovieEntry.COL_ORTITEL + " = ?";
final String[] where = {cur.getString(index_ortTitel)};
picturedb.close();// db not needed so is closed
if (cur.isNull(index_FilePath)) {//if file not already saved in the storage save it there
FetchImage getImage = new FetchImage(mContext, new FetchImage.AsyncResponse() {
#Override
public void processfinished(Bitmap output) { // get the image as an Bitmap in asynchronus task throug interface callback
FileOutputStream fos = null;
try {
fos = mContext.openFileOutput(Filename, Context.MODE_PRIVATE);
if (fos != null)
output.compress(Bitmap.CompressFormat.PNG, 100, fos); //put bitmap in file
} catch (IOException e) {
e.printStackTrace();
} finally {
if (fos != null) {
try {
fos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
ContentValues values = new ContentValues();
values.put(MovieContract.MovieEntry.COL_FILE, Filename);
SQLiteDatabase picwr = new MvDBHelper(mContext).getWritableDatabase();
int updated = picwr.update(MovieContract.MovieEntry.TABLE_NAME, values, selection, where);
//put the filname in the db for later use
picwr.close();
}
BitmapDrawable draw = new BitmapDrawable(mContext.getResources(), output);
Drawable gridimag = draw;
imageview.setImageDrawable(gridimag); // set the drawable as an image
}
});
String[] ptg = {cur.getString(index_PosterPath)};
getImage.execute(ptg);
} else { // if pic already saved in the internal storage get it from there
FileInputStream fis = null;
try {
fis = mContext.openFileInput(Filename);
Bitmap pic = BitmapFactory.decodeStream(fis);
BitmapDrawable draw = new BitmapDrawable(mContext.getResources(), pic);
Drawable gridimag = draw;
imageview.setImageDrawable(gridimag);
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
fis.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
cur.close();
}
return imageview;
}
public int getw(char c) {
int DisplayWidth = mContext.getResources().getDisplayMetrics().widthPixels;
if (c == 'w') {
return (int) (DisplayWidth / 2);
} else {
return DisplayWidth;
}
}
public static float convertDpToPixel(float dp, Context context) {
Resources resources = context.getResources();
DisplayMetrics metrics = resources.getDisplayMetrics();
float px = dp * ((float) metrics.densityDpi / DisplayMetrics.DENSITY_DEFAULT);
return px;
}
#Override
public void processfinished(Bitmap output) {
}
}
Would be happy about every help I can get even if it's a complet new Way because at the moment the grid view does not work fluently
You should avoid close cursor each time you draw a cell. You can close it only when you done with your activity.
Also you need to avoid using cur.moveToFirst(). Because you are already moving your cursor to given position, why should i moving it first before?
Another trick to use a image loader library (Picasso is one of the best) to load it async and faster. It also handles to stop threads if view is not shown. More optimized.
You dont need to find indexs of coloumn each time you want a new cell. Find them once, use them everytime :)
Also you can use CursorAdapter class to implement it way better :)
Related
When I display album art directly in my music app, it hangs. In stackoverflow, someone suggested me to implemented AsyncTask. So, I implemented AsyncTask to make my app faster. Right now, my app is not hanging but it is not displaying correct album art. And album arts are random means changing frequently when I scroll my listview.
Please help me.
Here is AsyncTask class :
class BitmapWorkerTask extends AsyncTask<Integer, Void, Bitmap> {
private final WeakReference<ImageView> imageViewReference;
private int data = 0;
private long l;
public BitmapWorkerTask(ImageView imageView) {
// Use a WeakReference to ensure the ImageView can be garbage collected
imageViewReference = new WeakReference<ImageView>(imageView);
}
public BitmapWorkerTask(ImageView imageView, long l) {
// Use a WeakReference to ensure the ImageView can be garbage collected
imageViewReference = new WeakReference<ImageView>(imageView);
this.l = l;
}
// Decode image in background.
#Override
protected Bitmap doInBackground(Integer... params) {
//Bitmap art = getAlbumart(songlist.this, l);
Context context = songlist.this;
Bitmap bm = null;
BitmapFactory.Options options = new BitmapFactory.Options();
try {
final Uri sArtworkUri = Uri.parse("content://media/external/audio/albumart");
Uri uri = ContentUris.withAppendedId(sArtworkUri, l);
ParcelFileDescriptor pfd = context.getContentResolver().openFileDescriptor(uri, "r");
if (pfd != null) {
FileDescriptor fd = pfd.getFileDescriptor();
bm = BitmapFactory.decodeFileDescriptor(fd, null, options);
pfd = null;
fd = null;
}
} catch (Error ee) {
} catch (Exception e) {
}
return bm;
}
// Once complete, see if ImageView is still around and set bitmap.
#Override
protected void onPostExecute(Bitmap bitmap) {
if (imageViewReference != null && bitmap != null) {
final ImageView imageView = imageViewReference.get();
if (bitmap != null) {
iv_art.setImageBitmap(bitmap);
} else {
iv_art.setImageResource(R.mipmap.app_splash_screen_icon);
}
}
}
}
My class which displays song in the listview :
public class MediaCursorAdapter extends SimpleCursorAdapter {
String backgroundColor = "white";
String someOtherBackgroundColor = "#FAFAFA";
public MediaCursorAdapter(Context context, int layout, Cursor c) {
super(context, layout, c,
new String[]{MediaStore.MediaColumns.DISPLAY_NAME, MediaStore.MediaColumns.TITLE, MediaStore.Audio.AudioColumns.DURATION, MediaStore.Audio.Media.ALBUM_ID},
new int[]{R.id.displayname, R.id.title, R.id.duration, R.id.iv_art});
}
#Override
public void bindView(View view, Context context, Cursor cursor) {
if (cursor.getPosition() % 2 == 0) {
view.setBackgroundColor(
Color.parseColor(backgroundColor));
} else {
view.setBackgroundColor(
Color.parseColor(someOtherBackgroundColor));
}
TextView title = (TextView) view.findViewById(R.id.title);
TextView name = (TextView) view.findViewById(R.id.displayname);
TextView duration = (TextView) view.findViewById(R.id.duration);
iv_art = (ImageView) view.findViewById(R.id.iv_art);
String a = cursor.getString(cursor.getColumnIndex(MediaStore.Audio.Media.ALBUM_ID));
l = Long.parseLong(a);
bwc = new BitmapWorkerTask(iv_art,l);
bwc.execute();
long durationInMs = Long.parseLong(cursor.getString(
cursor.getColumnIndex(MediaStore.Audio.AudioColumns.DURATION)));
name.setText(cursor.getString(
cursor.getColumnIndex(MediaStore.MediaColumns.DISPLAY_NAME)));
title.setText(cursor.getString(
cursor.getColumnIndex(MediaStore.MediaColumns.TITLE)));
Utility d = new Utility();
String durationInMin = d.convertDuration(durationInMs);
duration.setText("" + durationInMin);
view.setTag(cursor.getString(cursor.getColumnIndex(MediaStore.MediaColumns.DATA)));
}
#Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
LayoutInflater inflater = LayoutInflater.from(context);
View v = inflater.inflate(R.layout.songlist_listitem, parent, false);
bindView(v, context, cursor);
return v;
}
}
Its because of row reordering. The image view you want to load it into when you start a fetch is not necessarily where you want to load it at the end. The weak reference isn't helping because the view isn't being destroyed, its just not the right one anymore.
Instead of loading the data directly into the view, store it in a cache, then call notifyDataSetChanged. When you bind the row, check and see if the image is int he cache. If so, use it. If not, send the request. That will fix the majority of the issues you see, and prevent OOM errors (you can put a max memory usage on the cache).
Or use a library that does all this for you, like Volley.
I'm writing a gallery app.
It works from the androidstudio template for list fragment, with an AbsList.
I override getView to use a task and an lrucache to cache some bitmaps.
Each view from the listview is a RelativeLayout with an ImageView above a TextView.
If there is no Bitmap in the cache, then an AsyncTask loads it and puts it into the cache and getView draws a resource on the ImageView.
After it is loaded, onPostExecute puts the bitmap into the ImageView.
If there is a corresponding Bitmap on the cache, the it is set into the ImageView
I set an object holding the TextView and the ImageView along with an id into the getView's convertView parameter tag to keep track of the correct Bitmap to draw.
I have these two problems, though:
When I scroll down the first time, the new Image views appear with a previous bitmap for an instant before the task finishes setting up the correct bitmap (even though I draw a resource Bitmap on the adapter's getView) I don't understand why.
When I scroll back, most times the app crashes because the Bitmap on the cache turns out to be recycled, though I have no idea who recycled it.
Can anyone help me understand what happens here?
public View getView(int position, View convertView, ViewGroup parent) {
Log.i(TAG, "getView: Asking for view " + position);
GalleryItemViewHolder lViewHolder;
if (convertView == null) {
convertView = getActivity().getLayoutInflater().inflate(R.layout
.gallery_item, null);
lViewHolder = new GalleryItemViewHolder();
convertView.setTag(lViewHolder);
} else {
lViewHolder = (GalleryItemViewHolder) convertView.getTag();
}
lViewHolder.setId(position);
lViewHolder.setTextView((TextView) convertView.findViewById(R.id.gallery_infoTextView));
lViewHolder.setImageView((ImageView) convertView.findViewById(R.id.gallery_imageView));
lViewHolder.getTextView().setText(getItem(position).getName() + ": (" + getItem
(position).getCount() + ")");
if (!getItem(position).paintCover(lViewHolder.getImageView())) {
Log.i(TAG,"getView: task");
new GalleryItemTask(position, lViewHolder)
.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, null);
}
Log.i(TAG,"getView: return");
return convertView;
}
The Cover class has this paintCover method, where the mId is the uri/stream to the image
public boolean paintCover(ImageView imageView) {
Bitmap lBitmap;
if (mId == null || (lBitmap = BitmapCacheManager.getInstance().get(mId)) == null) {
i(TAG, "paintCover: Sin Cache ");
imageView.getHeight();
imageView.getWidth();
imageView.setImageResource(android.R.drawable.alert_dark_frame);
return false;
} else
{
i(TAG, "paintCover: En Cache "+lBitmap.isRecycled());
imageView.setImageBitmap(lBitmap);
return true;
}
}
More detail.
At the Fragment's onCreate, I run this method:
private void prepareGalleryLoaders() {
LoaderManager lm = getLoaderManager();
Log.i(TAG, "prepareGalleryLoaders: Iniciando loader");
lm.initLoader(IdConstants.GALLERY_LOADER, null, new GalleryLoaderCallbacks());
}
/**
* Callbacks para cargar los datos de las galerías
* Al terminar de cargarlas, se crea el nuevo arreglo
*/
private class GalleryLoaderCallbacks implements LoaderManager.LoaderCallbacks<List<Gallery>> {
#Override
public Loader<List<Gallery>> onCreateLoader(int id, Bundle args) {
return new GalleriesLoader(getActivity());
}private class GalleryItemTask extends AsyncTask<Void, Void, Gallery> {
private static final String TAG = "GalleryItemTask";
private int mId;
private String mCoverId;
private GalleryItemViewHolder mViewHolder;
private Bitmap mBitmap;
GalleryItemTask(int id, GalleryItemViewHolder galleryItemViewHolder) {
mViewHolder = galleryItemViewHolder;
mId = id;
}
#Override
protected void onPostExecute(Gallery galleries) {
if (mId != mViewHolder.getId()) {
Log.i(TAG, "onPostExecute: IDs difieren!!! "+mId+" - "+mViewHolder.getId());
mBitmap.recycle();
mBitmap=null;
return;
}
// Validar y actualizar bitmap
mViewHolder.getImageView().setImageBitmap(mBitmap);
//mGalleries.get(mId).setBitmap(mBitmap);
super.onPostExecute(galleries);
}
#Override
protected Gallery doInBackground(Void... params) {
// generar bitmap (y posiblemente agregarlo a algún cache)
String[] queryProjection = {
MediaStore.Images.ImageColumns.DATA, MediaStore.Images.ImageColumns.TITLE};
String[] selectionArgs = new String[]{String.valueOf(mGalleries.get(mId).getId())};
Cursor lCursor = getView().getContext().getContentResolver().query(
MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
queryProjection, MediaStore.Images.ImageColumns.BUCKET_ID + "= ?",
selectionArgs, MediaStore.Images.ImageColumns.TITLE);
lCursor.moveToFirst();
while (!lCursor.isAfterLast()) {
//Log.i(TAG,"doInBackground: "+mGalleries.get(mId).getName()+" - "+lCursor.getString
// (1)+" - "+ lCursor.getString(0));
lCursor.moveToNext();
}
lCursor.moveToFirst();
Log.i(TAG, "doInBackground: " + mId + " - " + mViewHolder.getId());
BitmapFactory.Options lOptions = new BitmapFactory.Options();
lOptions.inJustDecodeBounds = true;
mBitmap = BitmapFactory.decodeFile(lCursor.getString(0), lOptions);
lOptions.inSampleSize = ImageUtils.calculateInSampleSize(lOptions, 256, 256);
lOptions.inJustDecodeBounds = false;
mBitmap = BitmapFactory.decodeFile(lCursor.getString(0), lOptions);
BitmapCacheManager.getInstance().put(lCursor.getString(0), mBitmap);
//if(mGalleries.get(mId).getBitmap()!=null)
// mGalleries.get(mId).getBitmap().recycle();
//mGalleries.get(mId).setBitmap(mBitmap);
if(!mGalleries.get(mId).hasCover()) {
SimpleCover lSimpleCover=new SimpleCover(getActivity(),lCursor.getString(0));
mGalleries.get(mId).setCover(lSimpleCover);
}
lCursor.close();
return null;
}
}
#Override
public void onLoadFinished(Loader<List<Gallery>> loader, List<Gallery> data) {
if (mGalleries != null) {
mGalleries.clear();
} else
mGalleries = new ArrayList<Gallery>();
mGalleries.addAll(data);
for (Gallery lGallery : data) {
Log.i(TAG, "onLoadFinished: " + lGallery.getName());
}
mAdapter.notifyDataSetChanged();
}
At this point, there are no covers defined, the gallery list is just loaded with titles and total contents and id data. The images (covers) are loaded at getView from the list adapter.
The GalleryItemTask class:
private class GalleryItemTask extends AsyncTask<Void, Void, Gallery> {
private static final String TAG = "GalleryItemTask";
private int mId;
private String mCoverId;
private GalleryItemViewHolder mViewHolder;
private Bitmap mBitmap;
GalleryItemTask(int id, GalleryItemViewHolder galleryItemViewHolder) {
mViewHolder = galleryItemViewHolder;
mId = id;
}
#Override
protected void onPostExecute(Gallery galleries) {
if (mId != mViewHolder.getId()) {
Log.i(TAG, "onPostExecute: IDs difieren!!! "+mId+" - "+mViewHolder.getId());
mBitmap.recycle();
mBitmap=null;
return;
}
// Validar y actualizar bitmap
mViewHolder.getImageView().setImageBitmap(mBitmap);
//mGalleries.get(mId).setBitmap(mBitmap);
super.onPostExecute(galleries);
}
#Override
protected Gallery doInBackground(Void... params) {
// generar bitmap (y posiblemente agregarlo a algún cache)
String[] queryProjection = {
MediaStore.Images.ImageColumns.DATA, MediaStore.Images.ImageColumns.TITLE};
String[] selectionArgs = new String[]{String.valueOf(mGalleries.get(mId).getId())};
Cursor lCursor = getView().getContext().getContentResolver().query(
MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
queryProjection, MediaStore.Images.ImageColumns.BUCKET_ID + "= ?",
selectionArgs, MediaStore.Images.ImageColumns.TITLE);
lCursor.moveToFirst();
while (!lCursor.isAfterLast()) {
//Log.i(TAG,"doInBackground: "+mGalleries.get(mId).getName()+" - "+lCursor.getString
// (1)+" - "+ lCursor.getString(0));
lCursor.moveToNext();
}
lCursor.moveToFirst();
Log.i(TAG, "doInBackground: " + mId + " - " + mViewHolder.getId());
BitmapFactory.Options lOptions = new BitmapFactory.Options();
lOptions.inJustDecodeBounds = true;
mBitmap = BitmapFactory.decodeFile(lCursor.getString(0), lOptions);
lOptions.inSampleSize = ImageUtils.calculateInSampleSize(lOptions, 256, 256);
lOptions.inJustDecodeBounds = false;
mBitmap = BitmapFactory.decodeFile(lCursor.getString(0), lOptions);
BitmapCacheManager.getInstance().put(lCursor.getString(0), mBitmap);
//if(mGalleries.get(mId).getBitmap()!=null)
// mGalleries.get(mId).getBitmap().recycle();
//mGalleries.get(mId).setBitmap(mBitmap);
if(!mGalleries.get(mId).hasCover()) {
SimpleCover lSimpleCover=new SimpleCover(getActivity(),lCursor.getString(0));
mGalleries.get(mId).setCover(lSimpleCover);
}
lCursor.close();
return null;
}
}
When I scroll down the first time, the new Image views appear with a
previous bitmap for an instant before the task finishes setting up the
correct bitmap (even though I draw a resource Bitmap on the adapter's
getView) I don't understand why.
It should be because you put notifyDataSetChanged() on the wrong place. Please post the code where you put it.
When I scroll back, most times the app crashes because the Bitmap on
the cache turns out to be recycled, though I have no idea who recycled
it.
I think its because you don't specify what to do if the paintCover is true :
if (!getItem(position).paintCover(lViewHolder.getImageView())) {
Log.i(TAG,"getView: task");
new GalleryItemTask(position, lViewHolder)
.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, null);
}
else
{
//what should the adapter do if paintCover is true?
}
If the error still exist, please post your GalleryItemTask code.
I have been trying to figure this out for days, but can't seem to find the solution.
The problem is that even after getting the album art bitmap from MediaStore, and converting it to a drawable, it is assigned to an ImageView in a custom ListView layout via HashMap (String, Object), but finally after running on actual device and emulator, no album art is shown.
No LogCat error either. The ImageView of the custom listview layout does not show the album art.
public class AllSongs extends Fragment
{
Bitmap bitmap = null;
BitmapDrawable drawable = null;
private ArrayList<HashMap<String,Object>> list = new ArrayList<HashMap<String,Object>>();
private HashMap<String, Object> item;
private SimpleAdapter sa;
private ListView listview;
...
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState)
{
...
AsyncTaskRunner runner = new AsyncTaskRunner();
runner.execute("500");
}
private class AsyncTaskRunner extends AsyncTask<String, String, String>
{
#Override
protected String doInBackground(String... params) {
getAllMusicFiles();
return "Done!";
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
listview.setAdapter(sa); //Set all the file in the list.
}
}
private void getAllMusicFiles() {
// TODO Auto-generated method stub
//Some audio may be explicitly marked as not being music
String selection = MediaStore.Audio.Media.IS_MUSIC + " != 0";
String[] projection = {
MediaStore.Audio.Media.TITLE,
MediaStore.Audio.Media.ARTIST,
MediaStore.Audio.Media.ALBUM,
MediaStore.Audio.Media.ALBUM_ID
};
Cursor cursor = getActivity().getApplicationContext().getContentResolver().query(
MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
projection,
selection,
null,
null);
while(cursor.moveToNext()){
item = new HashMap<String,Object>();
String title = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.TITLE));
String artist = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ARTIST));
String album = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ALBUM));
long albumId = cursor.getLong(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ALBUM_ID));
final Uri ART_CONTENT_URI = Uri.parse("content://media/external/audio/albumart");
Uri albumArtUri = ContentUris.withAppendedId(ART_CONTENT_URI, albumId);
ContentResolver res = context.getContentResolver();
InputStream in;
try { // Yes, the album art has been found. I am sure of this.
if(bitmap != null)
{
bitmap.recycle();
bitmap = null;
if(drawable != null)
{
drawable = null;
}
}
in = res.openInputStream(albumArtUri);
bitmap = BitmapFactory.decodeStream(in);
drawable = new BitmapDrawable(getResources(), bitmap);
} catch (FileNotFoundException e) { // Album not found so set default album art
e.printStackTrace();
drawable = (BitmapDrawable) getActivity().getResources().getDrawable(R.drawable.default_albumart);
}
item.put("icon", drawable);
item.put("title", title);
item.put("artist", artist);
list.add(item);
if(cursor.isLast())
{
sa = new SimpleAdapter(getActivity(), list,
R.layout.custom_listview_layout,
new String[] {"icon", "title","artist" },
new int[] {R.id.icon,R.id.title, R.id.artist});
}
}
}
I have detected that the drawable may be the one causing the image to not be shown because if I replace -
item.put("icon", drawable);
with -
item.put("icon", R.drawable.default_albumart);
it shows the default album art.
Any idea what's causing this?
It's your adapter implementation is causing the problems, not the Drawable.
Look at these two lines of code:
item.put("icon", drawable) - this puts a Drawable object to your hashmap
item.put("icon", R.drawable.default_albumart) - this puts an int value to your map, but as map only works with objects, it is autoboxed before being put there
Thus, the problem is that your adapter works fine with integer identifiers of drawables, but not the drawables themselves. These are the constraints of SimpleAdapter
To solve this issue I would suggest you to implement your custom CursorAdapter. Its implementation is simply straightforward, and will save you from unnecessary steps, such as creating unnecessary lists, hashmaps etc, wasting app memory.
Feel free to ask anything else in comments, good luck!
The answer was given correctly by Drew but here is how it was finally implemented. Here are the changes -
private void getAllMusicFiles() {
// TODO Auto-generated method stub
//Some audio may be explicitly marked as not being music
String selection = MediaStore.Audio.Media.IS_MUSIC + " != 0";
String[] projection = {
MediaStore.Audio.Media._ID, // this is required acc to documentation
MediaStore.Audio.Media.TITLE,
MediaStore.Audio.Media.ARTIST,
MediaStore.Audio.Media.ALBUM,
MediaStore.Audio.Media.ALBUM_ID
};
cursor = getActivity().getApplicationContext().getContentResolver().query(
MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
projection,
selection,
null,
null);
getActivity().startManagingCursor(cursor);
listview.setAdapter(new CustomCursorAdapter(context, cursor));
}
#Override
public void onDestroy() {
// TODO Auto-generated method stub
if(cursor != null)
{
getActivity().stopManagingCursor(cursor);
cursor.close();
}
super.onDestroy();
}
removed the AsyncTask as it wasn't here required anymore.
#Override
public void onViewCreated(View view, Bundle savedInstanceState)
{
...
AsyncTaskRunner runner = new AsyncTaskRunner();
runner.execute("500");
}
CustomCursorAdapter.java -
public class CustomCursorAdapter extends CursorAdapter {
#SuppressWarnings("deprecation")
public CustomCursorAdapter(Context context, Cursor c) {
super(context, c);
// TODO Auto-generated constructor stub
}
private Bitmap bitmap = null;
private BitmapDrawable drawable = null;
#Override
public void bindView(View view, Context context, Cursor cursor) {
// TODO Auto-generated method stub
TextView title1 = (TextView) view.findViewById(R.id.title);
TextView artist1 = (TextView) view.findViewById(R.id.artist);
ImageView album1 = (ImageView) view.findViewById(R.id.icon);
String title = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.TITLE));
String artist = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ARTIST));
String album = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ALBUM));
long albumId = cursor.getLong(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ALBUM_ID));
StringBuilder titleBuild = new StringBuilder();
titleBuild.append(title);
if(titleBuild.length() > 35)
{
titleBuild.setLength(32);
title = titleBuild.toString()+"...";
}
else
{
title = titleBuild.toString();
}
StringBuilder artistBuild = new StringBuilder();
artistBuild.append(artist);
if(artistBuild.length() > 35)
{
artistBuild.setLength(32);
artist = artistBuild.toString()+"...";
}
else
{
artist = artistBuild.toString();
}
final Uri ART_CONTENT_URI = Uri.parse("content://media/external/audio/albumart");
Uri albumArtUri = ContentUris.withAppendedId(ART_CONTENT_URI, albumId);
ContentResolver res = context.getContentResolver();
InputStream in;
try {
if(bitmap != null)
{
bitmap = null;
if(drawable != null)
{
drawable = null;
}
}
in = res.openInputStream(albumArtUri);
bitmap = BitmapFactory.decodeStream(in);
// bitmap = MediaStore.Images.Media.getBitmap(context.getContentResolver(), albumArtUri);
drawable = new BitmapDrawable(context.getResources(), bitmap);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
drawable = (BitmapDrawable) context.getResources().getDrawable(R.drawable.default_albumart);
}
album1.setImageDrawable(drawable);
title1.setText(title);
artist1.setText(artist);
}
#Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
// TODO Auto-generated method stub
LayoutInflater inflater = (LayoutInflater)context.getSystemService
(Context.LAYOUT_INFLATER_SERVICE);
return inflater.inflate(R.layout.custom_listview_layout, parent, false);
}
}
I am struggling to update a list view with data from a database, this works nicely by using a SimpleCursorAdapter. But the image view on the rows is not updated on the activity start, I have to scroll through the list a few times and only then the images are loaded in the image view.
This is the binder i am using for the SimpleCursorAdapter:
private class PromotionViewBinder implements SimpleCursorAdapter.ViewBinder {
private int done;
public boolean setViewValue(View view, Cursor cursor, int index) {
Log.e(""+cursor.getCount(),"");
View tmpview = view;
if (index == cursor.getColumnIndex(PromotionsTable.SEEN_COL)) {
boolean read = cursor.getInt(index) > 0 ? true : false;
TextView title = (TextView) tmpview;
if (!read) {
title.setTypeface(Typeface.DEFAULT_BOLD, 0);
} else {
title.setTypeface(Typeface.DEFAULT);
}
return true;
} else if (tmpview.getId() == R.id.promotions_list_row_image){
String imageURL = cursor.getString(index);
Log.e("",imageURL);
imageRetriever.displayImage(imageURL, (ImageView)tmpview);
return true;
} else {
return false;
}
}
}
The image retriever class is the LazyList example from here. As you will see this is using a runnable to retrieve the images and once the task is done is automatically updating the given imageView...Do you think that the reference to the imageView is lost somewhere on the way?
Thanx in advance,
Nick
package com.tipgain.promotions;
The image retriever class:
/**
* This class is used for retrieving images from a given web link. it uses local
* storage and memory to store the images. Once a image is downloaded
* successfully the UI gets updated automatically.
*
*
*/
public class ImageRetriever {
private final String TAG = ImageRetriever.class.getName();
private MemoryImageCache memoryImgCache = new MemoryImageCache();
private LocalStorageImageCache localFileCache;
private Map<ImageView, String> imageViewHolders = Collections
.synchronizedMap(new WeakHashMap<ImageView, String>());
private ExecutorService execService;
final int defaultImageID = R.drawable.photo_not_available;
public ImageRetriever(Context context) {
localFileCache = new LocalStorageImageCache(context);
execService = Executors.newFixedThreadPool(5);
}
public void displayImage(String url, ImageView imageView) {
imageViewHolders.put(imageView, url);
Bitmap bmp = memoryImgCache.retrieve(url);
if (bmp != null) {
Log.e("case 1", " " + (bmp != null));
imageView.setImageBitmap(bmp);
} else {
Log.e("case 2", " " + (bmp == null));
addImageToQueue(url, imageView);
imageView.setImageResource(defaultImageID);
}
}
private void addImageToQueue(String url, ImageView imageView) {
NextImageToLoad img = new NextImageToLoad(url, imageView);
execService.submit(new ImagesRetriever(img));
}
/**
* This method is used for retrieving the Bitmap Image.
*
* #param url
* String representing the url pointing to the image.
* #return Bitmap representing the image
*/
private Bitmap getBitmap(String url) {
File imageFile = localFileCache.getFile(url);
// trying to get the bitmap from the local storage first
Bitmap bmp = decodeImageFile(imageFile);
if (bmp != null)
return bmp;
// if the file was not found locally we retrieve it from the web
try {
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(imageFile);
Utils.CopyStream(is, os);
os.close();
bmp = decodeImageFile(imageFile);
return bmp;
} catch (MalformedURLException e) {
Log.e(TAG, e.getMessage());
} catch (FileNotFoundException e) {
Log.e(TAG, e.getMessage());
} catch (IOException e) {
Log.e(TAG, e.getMessage());
}
return null;
}
/**
* This method is used for decoding a given image file. Also, to reduce
* memory, the image is also scaled.
*
* #param imageFile
* #return
*/
private Bitmap decodeImageFile(File imageFile) {
try {
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeStream(new FileInputStream(imageFile), null,
options);
// Find the correct scale value. It should be the power of 2.
// Deciding the perfect scaling value. (^2).
final int REQUIRED_SIZE = 100;
int tmpWidth = options.outWidth, tmpHeight = options.outHeight;
int scale = 1;
while (true) {
if (tmpWidth / 2 < REQUIRED_SIZE
|| tmpHeight / 2 < REQUIRED_SIZE)
break;
tmpWidth /= 2;
tmpHeight /= 2;
scale *= 2;
}
// decoding using inSampleSize
BitmapFactory.Options option2 = new BitmapFactory.Options();
option2.inSampleSize = scale;
return BitmapFactory.decodeStream(new FileInputStream(imageFile),
null, option2);
} catch (FileNotFoundException e) {
Log.e(TAG, e.getLocalizedMessage());
}
return null;
}
private boolean reusedImage(NextImageToLoad image) {
Context c = image.imageView.getContext();
c.getContentResolver().notifyChange(PromotionsProvider.CONTENT_URI, null);
String tag = imageViewHolders.get(image.imageView);
if ((tag == null) || (!tag.equals(image.url)))
return true;
return false;
}
/**
* Clears the Memory and Local cache
*/
public void clearCache() {
memoryImgCache.clear();
localFileCache.clear();
}
/**
* This class implements a runnable that is used for updating the promotions
* images on the UI
*
*
*/
class UIupdater implements Runnable {
Bitmap bmp;
NextImageToLoad image;
public UIupdater(Bitmap bmp, NextImageToLoad image) {
this.bmp = bmp;
this.image = image;
Log.e("", "ui updater");
}
public void run() {
Log.e("ui updater", "ui updater");
if (reusedImage(image))
return;
Log.e("nick", "" + (bmp == null) + " chberugv");
if (bmp != null){
image.imageView.setImageBitmap(bmp);
Context c = image.imageView.getContext();
c.getContentResolver().notifyChange(PromotionsProvider.CONTENT_URI, null);
}else
image.imageView.setImageResource(defaultImageID);
}
}
private class ImagesRetriever implements Runnable {
NextImageToLoad image;
ImagesRetriever(NextImageToLoad image) {
this.image = image;
}
public void run() {
Log.e("images retirever", " images retriever");
if (reusedImage(image))
return;
Bitmap bmp = getBitmap(image.url);
memoryImgCache.insert(image.url, bmp);
if (reusedImage(image))
return;
UIupdater uiUpdater = new UIupdater(bmp, image);
Activity activity = (Activity) image.imageView.getContext();
activity.runOnUiThread(uiUpdater);
//Context c = image.imageView.getContext();
//c.getContentResolver().notifyChange(PromotionsProvider.CONTENT_URI, null);
}
}
/**
* This class encapsulates the image being downloaded.
*
* #author Nicolae Anca
*
*/
private class NextImageToLoad {
public String url;
public ImageView imageView;
public NextImageToLoad(String u, ImageView i) {
url = u;
imageView = i;
}
}
}
Modified Runnable:
class UIupdater implements Runnable {
Bitmap bmp;
NextImageToLoad image;
public UIupdater(Bitmap bmp, NextImageToLoad image) {
this.bmp = bmp;
this.image = image;
}
public void run() {
if (reusedImage(image))
return;
if (bmp != null){
image.imageView.setImageBitmap(bmp);
Context c = image.imageView.getContext();
c.getContentResolver().notifyChange(PromotionsProvider.CONTENT_URI, null);
}else
image.imageView.setImageResource(defaultImageID);
}
}
Thats an interesting way to do what you are doing. Have you tried extending the Simple Cursor Adapter?
What you do is implement a ViewHolder and put your imageview in it.
Then in your ImageRetriever, write a Listener which will be called once the image is ready and retrieved.
Implement this listener in the Viewholder.
You create the view in getView() and request for the image in BindView().
Once the image gets loaded, the list will be refreshed automatically.
one way to do it is by calling notifyDataSetChenged on listview, and another was is to have adapter as member variable and when something changes on listview you call a function that assigns new listadapter to member adapter. That way your list will be redraw on change.
I guess, you have to use some handler, calling after image load, which will call notifyDataSetChanged for list adapter
I have to create a gridview that is loaded with images from a specific folder that resides on an SDCard. The path to the folder is "/sdcard/images/". i tried with this code,the app
is taking too much time to load and it is displaying only one image.
public class ImAdapterh extends BaseAdapter{
File dir=new File(Environment.getExternalStorageDirectory(),"/myImages/");
int count=dir.list().length;
String[] fileNames = dir.list();
private Context mContext;
public ImAdapterh(Context c) {
mContext = c;
}
public int getCount() {
return count;
}
public Object getItem(int position) {
return null;
}
public long getItemId(int position) {
return 0;
}
// create a new ImageView for each item referenced by the Adapter
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView = null;
for(String bitmapFileName : fileNames)
{
if (convertView == null)
{ // if it's not recycled, initialize some attributes
imageView = new ImageView(mContext);
imageView.setLayoutParams(new GridView.LayoutParams(85, 85));
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
imageView.setPadding(8, 8, 8, 8);
Bitmap bmp = BitmapFactory.decodeFile(dir.getPath() + "/" + bitmapFileName);
System.out.println(dir);
imageView.setImageBitmap(bmp);
}else
{
imageView = (ImageView) convertView;
}
}
return imageView;
}
the app is taking too much time and it is displaying only one image
this is my activity class
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
GridView gridview = (GridView) findViewById(R.id.gridview);
gridview.setAdapter(new ImAdapterh(this));}
The path to the folder is "/sdcard/images/".
No, it is not, at least not for most devices. Never hard-code paths in Android. Always use Environment.getExternalStorageDirectory() to get the root of external storage.
i tried with this code,the app is taking too much time to load and it is displaying only one image.
Of course. There is very little correct in what you have done here.
The biggest problem is that your getView() loads every image into the same ImageView, for each and every row returned by your Adapter. Presumably, you should be only loading one image into the ImageView for a given row.
Your next-biggest problem is that you are doing disk I/O on the main application thread.
To get images from any specific directory. Use the following code
public void searchImageFromSpecificDirectory() {
String path = null;
String uri = MediaStore.Images.Media.DATA;
// if GetImageFromThisDirectory is the name of the directory from which image will be retrieved
String condition = uri + " like '%/GetImageFromThisDirectory/%'";
String[] projection = { uri, MediaStore.Images.Media.DATE_ADDED,
MediaStore.Images.Media.SIZE };
Vector additionalFiles = null;
try {
if (additionalFiles == null) {
additionalFiles = new Vector<String>();
}
Cursor cursor = managedQuery(
MediaStore.Images.Media.EXTERNAL_CONTENT_URI, projection,
condition, null, null);
if (cursor != null) {
boolean isDataPresent = cursor.moveToFirst();
if (isDataPresent) {
do {
path = cursor.getString(cursor.getColumnIndex(uri));
System.out.println("...path..."+path);
additionalFiles.add(path);
}while(cursor.moveToNext());
}
if (cursor != null) {
cursor.close();
}
}
} catch (Exception e) {
e.printStackTrace();
}
}