loading images from SD card directory in GridView

loading images from SD card directory in GridView - android

I've created an app that allows the user to create a photo album(Folder) on External Storage. Now I am trying to retrieve the images from said directory and display them inside a GridView. I'm using an AsyncTask to iterate through the directory of files using listFiles() and then creating a bitmap once I grab each image, recycle it, and then use it again. My problem is that nothing is showing up in my GridView. I've set up a few Log breaks and LogCat shows me that the iteration does happen and the images are retrieved. This leads me to think that I made a mistake somewhere in my Adapter class that binds the bitmaps to the Grid, possibly in getView? Or maybe I'm wrong. Any help on what I'm doing wrong? I tried to comment the code as much as possible and I've left out the unecessary pieces. Thanks
public class AlbumGridView extends Activity implements OnItemClickListener {
private GridView sdcardImages;
private ImageAdapter imageAdapter;
private Display display;
private Bitmap bitmap;
private Bitmap b;
File[] imageList;
private static final String TAG = "AlbumGridView";
String path;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
setContentView(R.layout.album_view);
//display =
//((Object) getSystemService(Context.WINDOW_SERVICE))).getDefaultDisplay();
path = getIntent().getStringExtra("key");
Toast.makeText(this, path, Toast.LENGTH_SHORT).show();
setupViews();
setProgressBarIndeterminateVisibility(true);
loadImages();
}
protected void onDestroy() {
super.onDestroy();
final GridView grid = sdcardImages;
final int count = grid.getCount();
ImageView v = null;
for (int i = 0; i < count; i++) {
v = (ImageView) grid.getChildAt(i);
((BitmapDrawable) v.getDrawable()).setCallback(null);
}
}
// Set up the GridView
private void setupViews() {
sdcardImages = (GridView) findViewById(R.id.gvAlbumView);
// sdcardImages.setNumColumns(display.getWidth()/95);
sdcardImages.setClipToPadding(false);
sdcardImages.setOnItemClickListener(AlbumGridView.this);
imageAdapter = new ImageAdapter(getApplicationContext());
// imageAdapter.setImageList(path);
sdcardImages.setAdapter(imageAdapter);
}
private void addImage(LoadedImage... value) {
for (LoadedImage image : value) {
imageAdapter.addPhoto(image);
imageAdapter.notifyDataSetChanged();
}
}
// Save Bitmap images to a list and return that list
#Override
public Object onRetainNonConfigurationInstance() {
final GridView grid = sdcardImages;
final int count = grid.getChildCount();
final LoadedImage[] list = new LoadedImage[count];
for (int i = 0; i < count; i++) {
final ImageView v = (ImageView) grid.getChildAt(i);
list[i] = new LoadedImage(
((BitmapDrawable) v.getDrawable()).getBitmap());
}
return list;
}
private void loadImages() {
// TODO Auto-generated method stub
final Object data = getLastNonConfigurationInstance();
if (data == null) {
new LoadImagesFromSDCard().execute();
} else {
final LoadedImage[] photos = (LoadedImage[]) data;
if (photos.length == 0) {
new LoadImagesFromSDCard().execute();
}
for (LoadedImage photo : photos) {
addImage(photo);
}
}
}
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
// TODO Auto-generated method stub
}
/-------------------------------------------------------------------------------------/
//Adapter for the GridView
public class ImageAdapter extends BaseAdapter {
private Context mContext;
private ArrayList<LoadedImage> photos = new ArrayList<LoadedImage>();
private String path;
private Bitmap bitmap;
public ImageAdapter(Context context) {
mContext = context;
}
public void addPhoto(LoadedImage photo) {
photos.add(photo);
}
public int getCount() {
return photos.size();
}
public Object getItem(int position) {
return photos.get(position);
}
public long getItemId(int position) {
return position;
}
/*
* public File[] setImageList(String path) {
*
* //this.path = path; //this.imageList = imageList; //File imagesDir =
* new File(path); //imageList = imagesDir.listFiles();
*
* File imagesDir = new File(path); imageList = imagesDir.listFiles();
* for (File image : imageList) try { bitmap =
* BitmapFactory.decodeStream(image.toURL().openStream()); //use bitmap
* and recycle afterwards LoadedImage lm = new LoadedImage(bitmap);
* this.addPhoto(lm); bitmap.recycle();
*
* } catch (IOException e) { e.printStackTrace(); } return imageList;
*
* }
*/
public View getView(int position, View convertView, ViewGroup parent) {
final ImageView imageView;
if (convertView == null) {
imageView = new ImageView(mContext);
} else {
imageView = (ImageView) convertView;
}
imageView.setScaleType(ImageView.ScaleType.FIT_CENTER);
imageView.setPadding(2, 2, 2, 2);
// imageView.setImageBitmap(photos.get(position).getBitmap());
try {
imageView
.setImageBitmap(BitmapFactory
.decodeStream(imageList[position].toURL()
.openStream()));
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return imageView;
}
}
/*-------------------------------------------------------------------------*/
//AsyncTask to get the images
class LoadImagesFromSDCard extends AsyncTask<Object, LoadedImage, Object> {
#Override
protected Object doInBackground(Object... arg0) {
// Load images from SD card in Background
// Display each image on the screen
File imagesDir = new File(path);
imageList = imagesDir.listFiles();
for (File image : imageList)
try {
if (bitmap != null) {
bitmap.recycle();
bitmap = null;
}
bitmap = BitmapFactory.decodeStream(image.toURL()
.openStream());
Log.e(TAG, "Grabbed Image " + image.getName());
// use bitmap then recycle after
LoadedImage lm = new LoadedImage(bitmap);
// addImage(lm);
// imageAdapter.addPhoto(lm);
// imageAdapter.setImageList(path);
// imageAdapter.addPhoto(lm);
// imageAdapter.setImageList(path);
// bitmap.recycle();
// addImage(lm);
// imageAdapter.addPhoto(lm);
Log.e(TAG, "Added Image " + lm.toString());
// imageAdapter.setImageList(path);
addImage(lm);
// bitmap.recycle();
// bitmap.recycle();
} catch (Exception e) {
e.printStackTrace();
}
return null;
}

Here's the solution btw, sorry It took so long to I wasn't aware that others were waiting for the answer. Sorry. The relevant code is below.
This is AsyncTask that will query the device's MediaStore and retrieve all the photos. Note that this is retrieving the thumbnails and not the full size images, and more specifically it's the MICRO_KIND. There is also a Thumbnail.MINI_KIND as well.
/*----------------------------ASYNC TASK TO LOAD THE PHOTOS--------------------------------------------------------*/
public class LoadPhotos extends AsyncTask<Object, Object, Object> {
#Override
protected Object doInBackground(Object... params) {
try {
final String[] columns = { MediaStore.Images.Media._ID };
final String orderBy = MediaStore.Images.Media._ID;
Cursor imagecursor = managedQuery(
MediaStore.Images.Media.EXTERNAL_CONTENT_URI, columns,
null, null, orderBy);
int image_column_index = imagecursor
.getColumnIndex(MediaStore.Images.Media._ID);
AllPhotosActivity.count = imagecursor.getCount();
AllPhotosActivity.windows = new Bitmap[AllPhotosActivity.count];
for (int i = 0; i < AllPhotosActivity.count; i++) {
imagecursor.moveToPosition(i);
// i = index;
int id = imagecursor.getInt(image_column_index);
windows[i] = MediaStore.Images.Thumbnails.getThumbnail(
getApplicationContext().getContentResolver(), id,
MediaStore.Images.Thumbnails.MICRO_KIND, null);
}
imagecursor.close();
} catch (Exception e) {
e.printStackTrace();
Log.d("AllPhotosActivity",
"Error occured while fetching all photos on device.");
}
return null;
}
#Override
protected void onPostExecute(Object result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
Handler mHandler = new Handler();
mHandler.post(new Runnable() {
public void run() {
pd.dismiss();
// imageAdapter.notifyDataSetChanged();
// sdcardImages.setAdapter(imageAdapter);
}
});
// pd.dismiss();
imagegrid.setAdapter(imageAdapter);
// pd.dismiss();
}
#Override
protected void onProgressUpdate(Object... values) {
// TODO Auto-generated method stub
super.onProgressUpdate(values);
}
}
Here's the adapter for the GridView that's going to bind your thumbnails to the gridview. My issue was simply in the getView method of my ImageAdapter, notice I'm setting my ImageView resources from different indexes of an array of Bitmaps I called windows.
public class ImageAdapter extends BaseAdapter {
private Context mContext;
public ImageAdapter(Context c) {
mContext = c;
}
public Object getItem(int position) {
// TODO Auto-generated method stub
return position;
}
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
ImageView i = (ImageView) convertView;
if (i != null) {
i.setImageBitmap(windows[position]);
} else {
i = new ImageView(mContext.getApplicationContext());
// i.setPadding(3, 3, 3, 3);
// i.setScaleType(ImageView.ScaleType.FIT_CENTER);
i.setAdjustViewBounds(true);
// i.setMaxHeight(200);
// i.setMaxWidth(200);
i.setPadding(3, 3, 3, 3);
i.setLayoutParams(new GridView.LayoutParams(92, 92));
i.setImageBitmap(windows[position]);
}
return i;
}
public int getCount() {
// TODO Auto-generated method stub
return count;
}
}

Related

Lazy Loading of image in listview by its position

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

Android Listview Scroll position

I have a ListView and a list view adapter. The adapter populates the ListView from a List. The list view has a onScrollListener. The problem I have is when on scroll new data are loaded to the view but the scroll bar jumps to the top of the view.
What I want is to keep the scroll position where it was!
Any help?
Thanks
List View class:
private class GetItems extends AsyncTask<Void, Void, Void>
{
#Override
protected void onPreExecute() {
super.onPreExecute();
// Create a progressdialog
mProgressDialog = new ProgressDialog(AppList.this);
// Set progressdialog title
mProgressDialog.setTitle("Loading more");
mProgressDialog.setMessage("loading);
mProgressDialog.setIndeterminate(false);
// Show progressdialog
mProgressDialog.show();
}
#Override
protected Void doInBackground(Void... params)
{
applicationList = new ArrayList();
try
{
GetDataAppList getDataAppList = new GetDataAppList();
JSONArray jsonData = getDataAppList.getJSONData(webfileName, limit, offset);
for (int i = 0; i <= jsonData.length() - 2; i++)
{
JSONObject c = jsonData.getJSONObject(i);
id = c.getString("id");
name = c.getString("name");
logo = c.getString("logo");
developer = c.getString("developer");
rate = c.getInt("rates");
category = c.getInt("category");
fileName = c.getString("filename");
path = c.getString("path");
appSize = c.getDouble("size");
if(category == 1001)
{
String gCat = c.getString("game_category");
applicationList.add(new ApplicationPojo(id,name,logo,developer,appSize,category,fileName,path,gCat));
}
else
{
applicationList.add(new ApplicationPojo(id,name,logo,developer,appSize,category,fileName,path));
}
}
JSONObject sizeObj = jsonData.getJSONObject(jsonData.length() - 1);
size = sizeObj.getInt("size");
}
catch (Exception ex)
{
Log.d("Thread:", ex.toString());
}
return null;
}
#Override
protected void onPostExecute(Void result)
{
// Locate the ListView in listview.xml
listview = (ListView) findViewById(R.id.listView);
// Pass the results into ListViewAdapter.java
adapter = new ListViewAdapter(AppList.this, applicationList,listview);
// Binds the Adapter to the ListView
listview.setAdapter(adapter);
// Close the progressdialog
mProgressDialog.dismiss();
// Create an OnScrollListener
listview.setOnScrollListener(new OnScrollListener() {
#Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
int threshold = 1;
int count = listview.getCount();
if (scrollState == SCROLL_STATE_IDLE) {
if (listview.getLastVisiblePosition() >= count - threshold) {
if (size >= offset)
{
new LoadMoreDataTask().execute();
offset = offset + 15;
}
else
{
Toast.makeText(getApplicationContext(), "ختم لست!", Toast.LENGTH_LONG).show();
}
}
}
}
#Override
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
// TODO Auto-generated method stub
}
});
RatingBar bar = (RatingBar) findViewById(R.id.ratingBarShow);
}
}
private class LoadMoreDataTask extends AsyncTask<Void, Void, Void> {
#Override
protected void onPreExecute() {
super.onPreExecute();
mProgressDialog = new ProgressDialog(AppList.this);
mProgressDialog.setTitle("Loading more");
mProgressDialog.setMessage("loading);
mProgressDialog.setIndeterminate(false);
mProgressDialog.show();
}
#Override
protected Void doInBackground(Void... params)
{
try
{
GetDataAppList getDataAppList = new GetDataAppList();
JSONArray jsonData = getDataAppList.getJSONData(webfileName, limit, offset);
for (int i = 0; i <= jsonData.length(); i++) {
JSONObject c = jsonData.getJSONObject(i);
id = c.getString("id");
name = c.getString("name");
logo = c.getString("logo");
developer = c.getString("developer");
rate = c.getInt("rates");
category = c.getInt("category");
fileName = c.getString("filename");
path = c.getString("path");
appSize = c.getDouble("size");
if(category == 1001)
{
String gCat = c.getString("game_category");
applicationList.add(new ApplicationPojo(id,name,logo,developer,appSize,category,fileName,path,gCat));
}
else
{
applicationList.add(new ApplicationPojo(id,name,logo,developer,appSize,category,fileName,path));
}
}
}
catch (Exception ex)
{
}
return null;
}
#Override
protected void onPostExecute(Void result)
{
int position = listview.getLastVisiblePosition();
adapter = new ListViewAdapter(AppList.this, applicationList,listview);
listview.setAdapter(adapter);
listview.setSelectionFromTop(position, 0);
mProgressDialog.dismiss();
}
}
The Adpater class:
public ListViewAdapter(Activity activity, ArrayList<ApplicationPojo> applicationList, ListView listView)
{
this.activity = activity;
this.applicationList = applicationList;
this.inflater = LayoutInflater.from(activity);
downloader = new ApkFileDownloader(activity);
this.listView = listView;
}
#Override
public int getCount() {
return applicationList.size();
}
#Override
public ApplicationPojo getItem(int position) {
return applicationList.get(position);
}
#Override
public long getItemId(int position) {
return position;
}
public View getView(final int position, View view, ViewGroup parent)
{
if (view == null)
{
holder = new ViewHolder();
view = inflater.inflate(R.layout.singleapp, null);
holder.openInstalledAppBtn = (ImageView) view.findViewById(R.id.openInstalledApp);
holder.downloadBtn = (ImageView) view.findViewById(R.id.updateApp);
holder.progressBar = (ProgressBar)view.findViewById(R.id.updateProgress);
holder.cancelBtn = (ImageView) view.findViewById(R.id.cancel);
holder.appName = (TextView) view.findViewById(R.id.appName);
holder.developer = (TextView) view.findViewById(R.id.developer);
holder.size = (TextView) view.findViewById(R.id.size);
holder.appCat = (TextView) view.findViewById((R.id.appCat));
holder.installBtn = (ImageView) view.findViewById(R.id.install);
holder.catlogo = (ImageView) view.findViewById(R.id.catlogo);
view.setTag(holder);
}
else
{
holder = (ViewHolder) view.getTag();
}
try
{
final View finalView = view;
holder.logo = (ImageView) finalView.findViewById(R.id.appLogo);
logoName = applicationList.get(position).getLogo();
Picasso.with(activity)
.load(IPClass.SERVERIP + logoName)
.into(holder.logo);
// holder.logo.setOnClickListener(new View.OnClickListener() {
// #Override
// public void onClick(View arg0) {
//
// }
// });
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
String appid = applicationList.get(position).getId();
int category = applicationList.get(position).getCategory();
Intent rec1Intent = new Intent(activity, AppView.class);
activity.startActivity(rec1Intent);
AppView appView = new AppView();
appView.setParameters(appid, category);
AppList.adapter.notifyDataSetChanged();
}
});
final String id = applicationList.get(position).getId();
final String path = applicationList.get(position).getPath();
final String fileName = applicationList.get(position).getFileName();
final String name = applicationList.get(position).getName();
final String developer = applicationList.get(position).getDeveloper();
final double size = applicationList.get(position).getSize();
final String logo = applicationList.get(position).getLogo();
final int category = applicationList.get(position).getCategory();
final String appName = applicationList.get(position).getFileName();
String checkAppInstalled = appName.substring(0,appName.length() - 4);
//------------CHECK IF APPLICATION IS INSTALLED ----------------------------------------
if(appInstalled(checkAppInstalled))
{
holder.downloadBtn.setVisibility(View.GONE);
holder.cancelBtn.setVisibility(View.GONE);
holder.progressBar.setVisibility(View.GONE);
holder.installBtn.setVisibility(View.GONE);
holder.openInstalledAppBtn.setVisibility(View.VISIBLE);
holder.openInstalledAppBtn.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View v) {
String fileName = (applicationList.get(position).getFileName());
String appToOpen = fileName.substring(0,fileName.length() - 4);
Context ctx = activity.getApplicationContext();
Intent mIntent = ctx.getPackageManager().getLaunchIntentForPackage(appToOpen);
String mainActivity = mIntent.getComponent().getClassName();
Intent intent = new Intent("android.intent.category.LAUNCHER");
intent.setClassName(appToOpen, mainActivity);
activity.startActivity(intent);
}
});
}
//------------- IF APPLICATION IS NOT ALREADY INSTALLED --------------------------------
else
{
//------------------------ CHECK IF APK EXISTS -------------------------------------
String filePath = Environment.getExternalStorageDirectory().toString();
File file = new File(filePath + "/appsaraai/" + fileName);
if(file.exists())
{
holder.downloadBtn.setVisibility(View.GONE);
holder.cancelBtn.setVisibility(View.GONE);
holder.openInstalledAppBtn.setVisibility(View.GONE);
holder.progressBar.setVisibility(View.GONE);
holder.installBtn.setVisibility(View.VISIBLE);
holder.installBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(new File(Environment.getExternalStorageDirectory() + "/appsaraai/" + fileName)), "application/vnd.android.package-archive");
activity.startActivity(intent);
for (int i = 0; i < DownloadLists.list.size(); i++) {
if (DownloadLists.list.get(i).getName().equals(name)) {
DownloadLists.list.remove(i);
}
}
}
});
AppList.adapter.notifyDataSetChanged();
}
//------------------ IF APK DOES NOT EXIST -----------------------------------------
else
{
//-----CHECK IF DOWNLOAD IS IN PROGRESS ----------------------------------------
if (ApkFileDownloader.applicationList.containsKey(name))
{
holder.downloadBtn.setVisibility(View.GONE);
holder.installBtn.setVisibility(View.GONE);
holder.openInstalledAppBtn.setVisibility(View.GONE);
new ApkFileDownloader(activity).getDownloadStatus(holder.progressBar, name, holder.installBtn, holder.cancelBtn);
holder.progressBar.setVisibility(View.VISIBLE);
holder.cancelBtn.setVisibility(View.VISIBLE);
holder.cancelBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
downloader.cancelDownload(name);
holder.cancelBtn.setVisibility(View.GONE);
holder.downloadBtn.setVisibility(View.VISIBLE);
DownloadLists dlist = new DownloadLists(activity);
dlist.deleteData(name);
try {
AppList.adapter.notifyDataSetChanged();
} catch (Exception ex) {
System.out.println(ex);
}
try
{
SearchResult.adapter.notifyDataSetChanged();
}
catch (Exception ex)
{
System.out.println(ex);
}
}
});
}
//-------------- IF DOWNLOAD IS NOT IN PROGRESS START NEW DOWNLOAD -------------
else
{
holder.progressBar.setVisibility(View.GONE);
holder.cancelBtn.setVisibility(View.GONE);
holder.installBtn.setVisibility(View.GONE);
holder.openInstalledAppBtn.setVisibility(View.GONE);
holder.downloadBtn.setVisibility(view.VISIBLE);
holder.downloadBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
holder.downloadBtn.setVisibility(View.GONE);
holder.cancelBtn.setVisibility(View.VISIBLE);
holder.cancelBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
downloader.cancelDownload(name);
holder.cancelBtn.setVisibility(View.GONE);
holder.downloadBtn.setVisibility(View.VISIBLE);
try {
AppList.adapter.notifyDataSetChanged();
} catch (Exception ex) {
System.out.println(ex);
}
try {
SearchResult.adapter.notifyDataSetChanged();
} catch (Exception ex) {
System.out.println(ex);
}
}
});
new Thread(new Runnable() {
#Override
public void run() {
try {
Bitmap logoImg = Picasso.with(activity).load(IPClass.SERVERIP + logo).get();
DownloadLists.list.add(new ApplicationPojo(id, name, developer, size, logoImg, holder.progressBar));
DownloadLists dlist = new DownloadLists(activity);
dlist.insertData(id, name, developer, size, fileName, logoImg);
UpdateServerDownload d = new UpdateServerDownload();
d.updateDownloadNo(id, category);
} catch (IOException e) {
e.printStackTrace();
}
}
}).start();
new ApkFileDownloader(activity).setParameters(path, fileName, name);
try {
AppList.adapter.notifyDataSetChanged();
} catch (Exception ex) {
System.out.println(ex);
}
try {
SearchResult.adapter.notifyDataSetChanged();
} catch (Exception ex) {
System.out.println(ex);
}
}
});
}
}
}
holder.appName.setText(applicationList.get(position).getName());
holder.developer.setText(applicationList.get(position).getDeveloper());
String sizeText = " میگابایت ";
String appSize =String.valueOf(applicationList.get(position).getSize()) + sizeText;
holder.size.setText(appSize);
if(category == 1001)
{
String cat = applicationList.get(position).getgCat();
holder.appCat.setText(" " + returnGameCat(cat));
holder.catlogo.setImageResource(R.drawable.gamecatlogo);
}
}
catch (Exception ex)
{
Log.d("Adapter Exception", ex.toString());
}
return view;
}
//--------------- A METHOD TO CHECK IF APPLICATION IS ALREADY INSTALLED ------------------------
public boolean appInstalled(String checkApp)
{
pm = activity.getPackageManager();
try
{
pm.getPackageInfo(checkApp, PackageManager.GET_ACTIVITIES);
isAppInstalled = true;
}
catch (PackageManager.NameNotFoundException e)
{
isAppInstalled = false;
}
return isAppInstalled;
}

You are doing wrong in your GetItems and LoadMoreDataTask AsyncTask. you are setting new adapter each time when you scroll down so when new data are loaded to the view the scroll bar jumps to the top of the view.
You need to call
adapter = new ListViewAdapter(AppList.this, applicationList,listview);
listview.setAdapter(adapter);
only first time then you have to only call
adapter.notifyDataSetChanged()
to update your ListView no need to set adapter each time when making new request and also you have to set OnScrollListener to ListView only one time currently new OnScrollListener is set each time when making new request.

You need to setAdapter first time when adapter is null or you are fetching data first time after it just call notifyDataSetChanged()

Save state of listview before updating and then restore:
// save index and top position
int index = mListView.getFirstVisiblePosition();
View v = mListView.getChildAt(0);
int top = (v == null) ? 0 : v.getTop();
// notify dataset changed or re-assign adapter here
// restore the position of listview
mListView.setSelectionFromTop(index, top);

The most Optimal Solution will be
// Save the ListView state (= includes scroll position) as a Parceble
Parcelable state = listView.onSaveInstanceState();
// e.g. set new items
listView.setAdapter(adapter);
// Restore previous state (including selected item index and scroll position)
listView.onRestoreInstanceState(state);
Reference : Retain Scroll Position Android ListView

why BitmapFactory.decodeStream(input) returns null in my code and my photo doesn't show?

I want to read some book's data and show them in a listview and show book's picture using bitmap. I can show other information but I cant show picture and I cant finde why because I did what ever bitmapping needs and befor I use this AsyncTask method my pictures were showing!
and wonderful thing is when I click on an Item, download layout showing book's pic properly and when I Open AllBooksActivity from first place again, it is showing pics properly toO!!!
here is my AllBooksActivity code:
public class AllBooksActivity extends Activity {
public ListItem adapter;
public ListView allbooklist;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_all_books);
new loadingbooks().execute();
}
private class loadingbooks extends AsyncTask<String, String, String> {
private ProgressDialog pDialog;
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(AllBooksActivity.this);
pDialog.setMessage("کتابها در حال بارگذاری، لطفا منتظر بمانید...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
#Override
protected String doInBackground(String... args) {
String res = JSONCommands.readData(MainActivity.params);
return res;
}
#Override
protected void onPostExecute(String res) {
if(res != null){
pDialog.dismiss();
AllBooksActivity.this.getActionBar().setTitle(MainActivity.how);
allbooklist = (ListView) findViewById(R.id.list_all);
allbooklist.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent in = new Intent(getApplicationContext(), DownloadActivity.class);
in.putExtra("MyClass", MainActivity.books_array.get(position));
startActivity(in);
}
});
adapter = new ListItem(AllBooksActivity.this, MainActivity.books_array);
allbooklist.setAdapter(adapter);
}
else {
pDialog.dismiss();
AlertDialog.Builder builder = new AlertDialog.Builder(AllBooksActivity.this)
.setTitle("خطا در برقراری ارتباط با سرور")
.setMessage("نمایش کتاب ناموفق :( اتصالات را بررسی کنید.");
builder.create().show();
}
}
}
here is my list adapter code:
public class ListItem extends BaseAdapter {
private int count;
private Context context;
private ArrayList<ShowBook> bookArray;
public ListItem(Context context, ArrayList<ShowBook> bookArray) {
this.count = bookArray.size();
this.context = context;
this.bookArray = bookArray;
}
#Override
public int getCount() {
// TODO Auto-generated method stub
return count;
}
#Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return null;
}
#Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return 0;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService( Context.LAYOUT_INFLATER_SERVICE );
View row = inflater.inflate(R.layout.list_item, parent, false);
TextView namketabltxt, nevisandeltxt, mozooltxt, qeymatltxt;
ImageView tasvirlimg;
namketabltxt = (TextView) row.findViewById(R.id.ltxt_namketab);
nevisandeltxt = (TextView) row.findViewById(R.id.ltxt_nevisande);
mozooltxt = (TextView) row.findViewById(R.id.ltxt_mozoo);
qeymatltxt = (TextView) row.findViewById(R.id.ltxt_qeymat);
tasvirlimg = (ImageView)row.findViewById(R.id.limg_tasvir);
namketabltxt.setText(MainActivity.books_array.get(position).namketab);
nevisandeltxt.setText(MainActivity.books_array.get(position).nevisande);
mozooltxt.setText(MainActivity.books_array.get(position).mozoo);
qeymatltxt.setText(MainActivity.books_array.get(position).qeymat);
JSONCommands.getpic(MainActivity.books_array.get(position).tasvir, tasvirlimg);
return row;
}
}
here is my DownloadActivity code:
#SuppressLint("ShowToast") public class DownloadActivity extends Activity {
TextView namketabdtxt, nevisandedtxt, mozoodtxt, qeymatdtxt, uplodkonandedtxt;
ImageView tasvirdimg;
Button dlbtn;
RatingBar rb;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_download);
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
namketabdtxt = (TextView) findViewById(R.id.dtxt_namketab);
nevisandedtxt = (TextView) findViewById(R.id.dtxt_nevisande);
mozoodtxt = (TextView) findViewById(R.id.dtxt_mozoo);
uplodkonandedtxt = (TextView) findViewById(R.id.dtxt_uplodkonande);
qeymatdtxt = (TextView) findViewById(R.id.dtxt_qeymat);
tasvirdimg = (ImageView) findViewById(R.id.dimg_tasvir);
dlbtn = (Button)findViewById(R.id.btn_dl);
rb = (RatingBar) findViewById(R.id.ratingBar1);
final ShowBook book = (ShowBook) getIntent().getSerializableExtra("MyClass");
this.getActionBar().setTitle(book.namketab);
namketabdtxt.setText(book.namketab);
nevisandedtxt.setText(book.nevisande);
mozoodtxt.setText(book.mozoo);
uplodkonandedtxt.setText(book.uplodkonande);
qeymatdtxt.setText(book.qeymat);
JSONCommands.getpic(book.tasvir, tasvirdimg);
dlbtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
DownloadFileFromURL downloader = new DownloadFileFromURL();
//downloader.setDownloadedFileName()
String name = book.fileketab.substring(book.fileketab.lastIndexOf("/") + 1);
downloader.setDownloadedFileName(name);
downloader.execute(JSONCommands.firstURL + book.fileketab);
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.download, menu);
return true;
}
private class DownloadFileFromURL extends AsyncTask<String, String, String> {
private String downloadedfileName;
#Override
protected void onPostExecute(String result) {
// TODO Auto-generated method stub
Toast.makeText(getApplicationContext(), "بارگذاری کتاب باموفقیت انجام شد", Toast.LENGTH_LONG).show();
Toast.makeText(getApplicationContext(), "برای دیدن آن به کتاب‌خانه مراجعه نمایید", Toast.LENGTH_LONG).show();
}
public void setDownloadedFileName(String downloadedfileName){
this.downloadedfileName = downloadedfileName;
}
/**
* Downloading file in background thread
* */
#Override
protected String doInBackground(String... surl) {
int count;
try {
URL url = new URL(surl[0]);
URLConnection conection = url.openConnection();
conection.connect();
// this will be useful so that you can show a typical 0-100%
// progress bar
int lenghtOfFile = conection.getContentLength();
// download the file
InputStream input = new BufferedInputStream(url.openStream(),
8192);
// Output stream
//OutputStream output = new FileOutputStream(Environment
// .getExternalStorageDirectory().toString()
// + "/data/" + downloadedfileName);
OutputStream output = new FileOutputStream(getFilesDir()+File.separator +downloadedfileName);
byte data[] = new byte[1024];
long total = 0;
while ((count = input.read(data)) != -1) {
total += count;
// publishing the progress....
// After this onProgressUpdate will be called
// publishProgress("" + (int) ((total * 100) / lenghtOfFile));
// writing data to file
output.write(data, 0, count);
}
// flushing output
output.flush();
// closing streams
output.close();
input.close();
} catch (Exception e) {
Log.e("Error: ", e.getMessage());
}
return null;
}
}
/**
* After completing background task called
* **/
}
and here is my getpic code using Bitmap(this function is in my JSONCommands class and that is why I called them as "JSONCommands.getpic"):
public static void getpic(String str, ImageView tasvir){
Bitmap bitmap;
if(str != null){
bitmap = getBitmapFromURL(firstURL+ str);
if(bitmap!=null){
tasvir.setImageBitmap(bitmap);
}
else{
tasvir.setImageResource(R.drawable.p3_books);
}
}
else{
tasvir.setImageResource(R.drawable.p3_books);
}
}
public static 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);
connection.disconnect();
return myBitmap;
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
I cant find the solution and it drives me crazy:) please help, tank you.

Android ListView wrong images

I'm developing an Android app but I'm a newbie and I got stuck...
My ListView single element has an ImageView and some TextViews, but sometimes (when I scroll the page and there are more than 7-8 elements) it doesn't display the right image in the right row.
I'm using a custom Image Loader to manage the downloaded images.
Here's my Adapter:
public class AddVideogameActivityAdapter extends BaseAdapter {
private ArrayList<Videogame> videogames;
private Typeface typefaceMedium;
private Typeface typefaceLight;
private ImageLoader loader;
private LayoutInflater mInflater;
public AddVideogameActivityAdapter(Context context, ArrayList<Videogame> results) {
videogames = results;
mInflater = LayoutInflater.from(context);
typefaceMedium = Typeface.createFromAsset(context.getAssets(), "Roboto-Medium.ttf");
typefaceLight = Typeface.createFromAsset(context.getAssets(), "Roboto-Light.ttf");
loader = new ImageLoader(context);
}
public int getCount() {
return videogames.size();
}
public Object getItem(int position) {
return videogames.get(position);
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = mInflater.inflate(R.layout.list_element,null);
holder = new ViewHolder();
holder.imgView = (ImageView) convertView.findViewById(R.id.thumbView);
holder.txtName = (TextView) convertView.findViewById(R.id.elementView);
holder.txtPlatform = (TextView) convertView.findViewById(R.id.elementView2);
convertView.setTag(holder);
}
else {
holder = (ViewHolder) convertView.getTag();
}
try {
Videogame vgame = (Videogame) videogames.get(position);
holder.txtName.setText(vgame.getTitle());
holder.txtName.setTypeface(typefaceMedium);
holder.txtPlatform.setText(videogames.get(position).getPlatform());
holder.txtPlatform.setTypeface(typefaceLight);
holder.imgUrl = videogames.get(position).getImage();
loader.display(holder.imgUrl, holder.imgView, R.drawable.youtube_icon);
}
catch (Exception e) {
e.printStackTrace();
Log.e(com.example.ludos2_0.MainActivity.TAG,
"Exception: " + e.getLocalizedMessage());
}
return convertView;
}
static class ViewHolder {
TextView txtName;
TextView txtPlatform;
public String imgUrl;
ImageView imgView;
}
}
Sorry for my english and thank you for your help!
EDIT:
Here's also the Loader:
public class ImageLoader implements ComponentCallbacks2 {
private TCLruCache cache;
public ImageLoader(Context context) {
ActivityManager am = (ActivityManager) context.getSystemService(
Context.ACTIVITY_SERVICE);
int memoryClass = am.getMemoryClass() * 1024 * 1024;
cache = new TCLruCache(memoryClass);
}
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);
}
}
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 = 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;
}
}
}
}
RE-EDIT
Activity code:
public class AddVideogameActivity extends ListActivity {
private TextView searchField = null;
private final Handler handler = new Handler();
private ArrayList<Videogame> videogamesList = null;
private static AddVideogameActivity mContext = null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_add_book);
mContext = this;
searchField = (TextView) findViewById(R.id.searchField);
searchField.setMaxLines(1);
searchField.setOnFocusChangeListener(new OnFocusChangeListener() {
#Override
public void onFocusChange(View v, boolean hasFocus) {
searchField.setHint("");
}
});
// Setup the list view and its listener
getListView().setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Log.d(MainActivity.TAG,
"AddBookActivity ---> AddButton:onClick()");
// Sets typefaces for TextView
String videogameId = videogamesList.get(position).getId();
String videogameName = videogamesList.get(position).getTitle();
String thumbnail = videogamesList.get(position).getThumbnail();
String description = videogamesList.get(position)
.getDescription();
String image = videogamesList.get(position).getImage();
String platform = videogamesList.get(position).getPlatform();
if (videogameName != null && videogameName.length() > 0
&& thumbnail != null && thumbnail.length() > 0
&& description != null && description.length() > 0
&& image != null && image.length() > 0
&& platform != null && platform.length() > 0) {
if (ListsManager.getInstance().addVideogame(
new Videogame(videogameId, videogameName,
thumbnail, image, description, platform)) == 0) {
Log.d(MainActivity.TAG,
"AddBookActivity --> Videogame:[" + videogameId
+ "#" + videogameName + "]");
Toast toast = Toast.makeText(mContext, "["
+ videogameName + "] Saved !",
Toast.LENGTH_LONG);
toast.show();
} else {
Log.e(MainActivity.TAG,
"AddBookActivity --> Error ! Videogame already in the list ! ");
Toast toast = Toast.makeText(mContext,
"Error! Videogame already in the list!",
Toast.LENGTH_LONG);
toast.show();
}
} else {
Log.e(MainActivity.TAG,
"AddBookActivity --> Error ! Invalid Videogame Name or Thumbnail or Id or Deck");
Toast toast = Toast
.makeText(
mContext,
"Error ! Invalid Videogame Name or Thumbnail or Id or Deck",
Toast.LENGTH_LONG);
toast.show();
}
Intent newIntent = new Intent(getApplicationContext(),
MainActivity.class);
startActivity(newIntent);
}
});
// Setup the search button and its listener
Button searchButton = (Button) findViewById(R.id.searchButton);
searchButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Log.d(com.example.ludos2_0.MainActivity.TAG, "Search Game ...");
String searchInputString = searchField.getText().toString();
if (searchInputString != null && searchInputString.length() > 0) {
try {
String requestURL = ("http://www.giantbomb.com/api/search/?api_key=fcf60d6d67b98b0d17b3905d1a90b3fd31ed1e8e&format=json&query="
+ Uri.encode(searchInputString) + "&resources=game");
// String requestURL =
// String.format("https://gdata.youtube.com/feeds/api/videos?v=2&alt=jsonc&category=Music&orderby=relevance&q=%s",Uri.encode(searchInputString));
Log.d(com.example.ludos2_0.MainActivity.TAG, requestURL);
DownloadGiantBombJSONData giantbombAsyncTask = new DownloadGiantBombJSONData();
giantbombAsyncTask.execute(new String[] { requestURL });
} catch (Exception e) {
e.printStackTrace();
}
}
}
});
if (videogamesList == null)
videogamesList = new ArrayList<Videogame>();
else
updateVideogamesListView(videogamesList);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.add_book, menu);
return true;
}
#Override
protected void onResume() {
super.onResume();
}
#Override
protected void onPause() {
super.onPause();
}
public void updateVideogamesListView(ArrayList<Videogame> values) {
AddVideogameActivityAdapter adapter = new AddVideogameActivityAdapter(this, values);
setListAdapter(adapter);
}
#Override
protected void onDestroy() {
super.onDestroy();
}
}
The other classes involved in building the ListView are the REST classes and the AsyncTask class that downloads and parses the JSon files.

What does your ListView look like, does it look like this:
<ListView android:id="#id/android:list"
android:layout_weight="1"
android:layout_width="match_parent"
android:layout_height="0dip" ></ListView>
Especially the id of the ListView. Check your layout file, probably the bug exists there.

Drawables won't load using AsyncTask

I have the queryAppIcon() method that queries and stores images in the array appIconDrawable. However, I'm only getting blank where images should pop up. Please let me know if I should post any other relevant code
This is the relevant code inside the ViewActivity:
// global vars
final Drawable[] appIconDrawable = null;
int i;
public Drawable[] queryAppIcon() throws ParseException, IOException {
ParseQuery<ParseObject> query = ParseQuery.getQuery("AndroidStoreContent");
query.whereExists("appIcon");
List<ParseObject> ParseResult = query.find();
// Drawable array
appIconDrawable = new Drawable[ParseResult.size()];
for (i = 0; i < ParseResult.size(); i++) {
ParseFile pf = (ParseFile) ParseResult.get(i).get("appIcon");
startDownload(pf);
}
return appIconDrawable;
}
public void startDownload(ParseFile pf) {
new DownloadImageTask(this).execute(pf);
}
public class DownloadImageTask extends AsyncTask<ParseFile, Void, Drawable> {
private AsyncResponse ar;
DownloadImageTask(AsyncResponse ar) {
this.ar = ar;
}
#Override
protected Drawable doInBackground(ParseFile... pf) {
return fetchDrawable(pf[0]);
}
protected void onPostExecute(Drawable result) {
ar.processFinish(result);
}
public Drawable fetchDrawable(ParseFile pf) {
InputStream is;
try {
is = (InputStream) new URL(pf.getUrl()).getContent();
return Drawable.createFromStream(is,null);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
}
#Override
public void processFinish(Drawable d) {
appIconDrawable[i] = d; // i also tried testing appIconDrawable[1] = d and the app loaded with all blank images and then crashes
}
This is the interface, AsyncResponse:
public interface AsyncResponse {
void processFinish(Drawable d);
}

It seems like you need a bit of refactor...
You are expecting Drawable[] from queryAppIcon() but you will always get an empty set because you start the download which takes place in a separate thread to then update the return value.
You should be setting the Drawable to the ImageView from within processFinish.
Signs of things done wrong: Async methods such as downloading images should never have a return value.
UPDATE
Here is a very simple download AsyncTask but there are many checks, optimizations, etc. missing, like CACHE! Also, ImageView inside DownloadImageTask should be held by a WeakReference (Google it) otherwise it WILL leak your activity.
public class DownloadImageTask extends AsyncTask<String, Void, Drawable> {
private static final String TAG = DownloadImageTask.class.getSimpleName();
private ImageView mImageView;
DownloadImageTask(ImageView imageView) {
mImageView = imageView;
}
#Override
protected Drawable doInBackground(String... url) {
return fetchDrawable(url[0]);
}
#Override
protected void onPostExecute(Drawable result) {
if (result != null) {
mImageView.setImageDrawable(result);
} else {
Log.w(TAG, "Could download image!");
}
}
public static Drawable fetchDrawable(String url) {
Log.v(TAG, "Downloading: " + url);
InputStream is;
try {
is = (InputStream) new URL(url).getContent();
return Drawable.createFromStream(is, null);
} catch (MalformedURLException e) {
Log.e(TAG, e.getMessage(), e);
} catch (IOException e) {
Log.e(TAG, e.getMessage(), e);
}
return null;
}
}
Adapter:
public class ImageDownloadAdapter extends ArrayAdapter<String>{
public ImageDownloadAdapter(Context context, String[] objects) {
super(context, R.layout.item_image_download, R.id.txt_url, objects);
}
#SuppressLint("NewApi")
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View view = super.getView(position, convertView, parent);
String url = getItem(position);
ImageView imageView = (ImageView) view.findViewById(R.id.img_download);
DownloadImageTask downloadImageTask = new DownloadImageTask(imageView);
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
downloadImageTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, url);
} else {
downloadImageTask.execute(url);
}
return view;
}
}
Activity:
ListView listView = (ListView) findViewById(android.R.id.list);
listView.setAdapter(new ImageDownloadAdapter(this, new String[]{
"http://www.beautystat.com/site/wp-content/uploads/2011/02/happy-faces-small.jpg",
"http://www.ducthide.com/new_wallet_pics/happy_face.JPG"
}));

Develop Reference

The Android operating system is a mobile operating system that was developed by Google (GOOGL?) to be primarily used for touchscreen devices, cell phones, and tablets.

loading images from SD card directory in GridView - android

Related

Lazy Loading of image in listview by its position

Android Listview Scroll position

why BitmapFactory.decodeStream(input) returns null in my code and my photo doesn't show?

Android ListView wrong images

Drawables won't load using AsyncTask

Categories

Resources