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Thumbnail for video from server not getting displayed in ImageView

Need to generate thumbnail from video stored in server, below is my code but "path" variable is giving problem, how to get it resolved. If i remove path parameter with url parameter then i am getting the thumbnails but not in proper order or sometimes same thumbnail is generated for 2 or 3 videos, below is my code -
Video video = mVideos.get(position);
//play video using android api, when video view is clicked.
url = video.getVideoUrl(); // your URL here
Uri videoUri = Uri.parse(url);
new DownloadImage(holder.videothumbView).execute(url);
public class DownloadImage extends AsyncTask<String, Void, Bitmap> {
ImageView bmImage;
public DownloadImage(ImageView bmImage) {
this.bmImage = (ImageView ) bmImage;
}
protected Bitmap doInBackground(String... urls) {
Bitmap myBitmap = null;
MediaMetadataRetriever mMRetriever = null;
try {
mMRetriever = new MediaMetadataRetriever();
if (Build.VERSION.SDK_INT >= 14)
mMRetriever.setDataSource(path, new HashMap<String, String>());
else
mMRetriever.setDataSource(path);
myBitmap = mMRetriever.getFrameAtTime();
} catch (Exception e) {
e.printStackTrace();
} finally {
if (mMRetriever != null) {
mMRetriever.release();
}
}
return myBitmap;
}
protected void onPostExecute(Bitmap result) {
bmImage.setImageBitmap(result);
}
}

All the network related task must be done in a separate thread. You can't do it in main thread. You can use Picasso image library. It is open source and you can show different image for different state like loading, error etc.
Picasso.with(context) // your activity of other context referance
.load(video.getVideoUrl())
.placeholder(R.drawable.user_placeholder) // this will show during image loading from network
.error(R.drawable.user_placeholder_error) // error image to display
.into(holder.videothumbView);

How to display an image with use of jar file in Android?

I am new for Android. I want to create an jar file if i call a method of that jar file in another android application it will show an image in imageview of the application. For example
a method in jar file as DisplayImg(URL); i will use this jar as library in another application and here i will create an imageview
ImageView imageView;
imageView = (ImageView) findViewById(R.id.img);
Then if i call imageView.DisplayImg(URL); then it will display specified url image on the imageview. I spend lot more time to get the solution but not work.plz help with the code thank

You don't need to create a library, in fact, there is a same library available for doing exactly what you want to!
It's called Picasso. You can find it here.
Also note that if you want imageView.DisplayImage(URL); you should create a new instance of ImageView class, because it doesn't contain this method. I recommend using DisplayImage(URL, imageView);.
But in case you REALLY WANT to do this, here you go:
1- For creating a library, create a New Android Application Project, and in the second window, check Mark this project as a library option. Also notice that we don't need Activity.
2- Create a new class, such as ImageUtils.java in the newly-created project. Here you need to put the DisplayImage() method:
public static void DisplayImage(String URL, ImageView imageView) {
new DownloadImageTask(imageView).execute(URL);
}
And this for the DownloadImageTask class :
public static class DownloadImageTask extends AsyncTask<String, Void, Bitmap> {
ImageView imageView;
public DownloadImageTask(ImageView bmImage) {
this.imageView = bmImage;
}
protected Bitmap doInBackground(String... urls) {
String urldisplay = urls[0];
Bitmap imageBitmap = null;
try {
InputStream in = new java.net.URL(urldisplay).openStream();
imageBitmap = BitmapFactory.decodeStream(in);
} catch (IOException e) {
// Probably there's no Internet connection. Warn the user about checking his/her connection.
Log.e("Error", e.getMessage());
e.printStackTrace();
}
return imageBitmap;
}
protected void onPostExecute(Bitmap result) {
if (imageView != null) imageView.setImageBitmap(result);
}
}
3- Execute your project as an android application.
4- There should be a jar file under the bin folder. It's your library. Import it to your other applications and use it. In that applications you can use it with this code:
ImageView imageView = (ImageView) findViewById(R.id.img);
ImageUtils.DisplayImage(URL, imageView);
5- Don't forget to add this permission to the apps that use this library:
<uses-permission android:name="android.permission.INTERNET" />
Hope it helps :)

Refresh ImageView from URL Android

I need some help. I want to refresh my ImageView loaded from a URL in my android app. I try use timers but doesn't work. Any thoughts?
I have this code in Main Activity:
public class Imagens extends Activity {
private ImageView imagem;
private Bitmap bit;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_imagens);
imagem=(ImageView) findViewById(R.id.imageView);
bit=getBitmapFromURL("http://www.onlinedegrees.org/wp-content/uploads/android1.jpg");
imagem.setImageBitmap(bit);
}
public 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 (Exception e){
e.printStackTrace();
return null;
}
}
}
And in the AndroidManifest uses:
uses-permission android:name="android.permission.INTERNET"
to allow internet connection.

I can recommend a different way that works like a charm: Android Query.
You can download that JAR file from here
AQuery androidAQuery = new AQuery(this);
As an example:
androidAQuery.id(YOUR IMAGEVIEW).image(YOUR IMAGE TO LOAD, true, true, getDeviceWidth(), ANY DEFAULT IMAGE YOU WANT TO SHOW);
It's very fast and accurate, and using this you can find many more features like animation when loading, getting a bitmap (if needed), etc.

Why doesn't android ImageAdapter load images lazily?

I have this ImageAdapter for android's listView:
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View view = null;
RelativeLayout relativeLayout = null;
Offer currentOffer = mOffersList.get(position);
if (convertView == null) { // create a new view if no recycling
// available
// Make up a new view
LayoutInflater inflater = (LayoutInflater) mContext
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = inflater.inflate(R.layout.offer_list_item, null);
relativeLayout = (RelativeLayout) view
.findViewById(R.id.offerImage);
} else {
view = (View) convertView;
relativeLayout = (RelativeLayout) view
.findViewById(R.id.offerImage);
setBackgroundDrawable(relativeLayout, null);
}
String imageUrl = "";
imageUrl = currentOffer.getImageUrl().toString();
Bitmap bitmap = imageCache.get(imageUrl);
if (bitmap != null) {
Drawable dr = new BitmapDrawable(mContext.getResources(), bitmap);
setBackgroundDrawable(relativeLayout, dr);
} else {
if (!downloadingImageUrls.contains(imageUrl)) {
downloadingImageUrls.add(imageUrl);
new DownloadImageAsyncTask().execute(imageUrl);
}
}
return view;
}
and this:
class DownloadImageAsyncTask extends AsyncTask<String, Void, Void> {
#Override
protected Void doInBackground(String... params) {
String imageUrl = params[0];
try {
Bitmap bitmap = BitmapFactory
.decodeStream((InputStream) new URL(imageUrl)
.getContent());
imageCache.put(imageUrl, bitmap);
} catch (IOException e) {
Log.e("DownloadImageAsyncTask", "Error reading bitmap" + e);
}
downloadingImageUrls.remove(imageUrl);
return null;
}
#Override
protected void onPostExecute(Void result) {
notifyDataSetChanged();
}
}
why do all of the list items loaded together? it's don' asynchronously but yet not one by one. All together.
how can i load it lazily?
and why is this code more efficient?
// better
public class DownloadImageAsyncTask2 extends
AsyncTask<String, Void, Bitmap> {
private final ImageView imageView;
public DownloadImageAsyncTask2(ImageView imageView) {
this.imageView = imageView;
}
#Override
protected void onPreExecute() {
Log.i("DownloadImageAsyncTask", "Starting image download task...");
}
#Override
protected Bitmap doInBackground(String... params) {
try {
return BitmapFactory.decodeStream((InputStream) new URL(
params[0]).getContent());
} catch (IOException e) {
Log.e("DownloadImageAsyncTask", "Error reading bitmap" + e);
}
return null;
}
#Override
protected void onPostExecute(Bitmap bitmap) {
if (bitmap != null) {
imageView.setImageBitmap(bitmap);
}
}
}

To answer your initial question, any adapter you write is exactly as it's called; it's an adapter. It lets you translate your data into Views displayed in an AdapterView. It would not make sense to force all views to be "loaded lazily" and, quite frankly, should not do that for a few reasons.
Maybe you have prefetched all your images and don't need lazy loading. Maybe they even just come from resources and don't need to be handled in a special way at all.
How would it know from where to lazily load your images (database, memory map, file, network resource, other android service, etc.)? That's your job when writing the adapter.
You might argue it would be nice for Adapter subclasses to have a loadLazily(Uri image, ImageView view) function. If so why not subclass AbsAdapter yourself and add it or submit a patch to the AOSP. I, however, doubt you will find agreement that even a function like that should be included as part of an Adapter. It's really your job to manage your data in an efficient manner, despite how normal it is to lean on the system for data management in Android.
To answer your other questions about the two methods of lazy loading you proposed, the difference is that the first method causes the AdapterView to reload all of its Views whereas in the second method you are simply invalidating the view into which you are loading the image.
I don't actually agree the second method is "better" on a whole because every time your configuration is changed or process dies and Views need to be reloaded you need to make new calls over the network or to the file system to load your images. If you cache them as you do in the first method then you can at least avoid needing to reload all the images through configuration changes. If you wrote a separate image loading service that ran in its own process (not something I'm recommending) you could also avoid the second case (of your :default process getting killed).
Point is, you're responsible for loading your images, not Android. If you want it done for you take a look at these great image loading or otherwise general resource acquisition libraries for android: Local image caching solution for Android: Square Picasso vs Universal Image Loader . I've personally used Universal-Image-Loader before and admit it works as advertised. However, it caches all your images on external storage which might not be an option for you.

The listview can call getView for all items in its onMeasure (cf. measureHeightOfChildren in listView.java).
So, with this getView, it loads all images.
To load lazily, you need to load images elsewhere: let the views ask the image when needed (onDraw) to a manager (which will load them asynchronously).
notifyDataSetChanged() with update all the listview (meaning recycling views, calling getView ...), imageView.setImageBitmap will update only the ImageView so it's a better idea.

use this imageloader it works IMAGELOADER

You can use this library https://github.com/thest1/LazyList. It's very easy to use.

viewpager imageview zoomin/zoomout landscape capture photo display not full width of imageview

I am using viewpager to view every single photo inside imageview using this :-
ZoomableImageView imageView = new ZoomableImageView(context);
Bitmap bimage= getBitmapFromURL(test);
imageView.setBitmap(bimage);
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);
return myBitmap;
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
the problem I am facing right now is that when i take photo in landscape mode and view the photo in landscape, the photo in imageview is not shown in full width of the devices. But when i capture it in portrait mode, it comes in full size and in landscape, it is not full size but centralized correctly. i wants to show full width for landscape photo just like the android native gallery.
Any idea?
Thanks in advance.