Develop Reference

loading full image from url into image view with any image loading library

I'm downloading an image from a URL and displaying it in an ImageView. I need to download the image at its full original size. I've tried Glide, Picasso and Universal Image Loader with no success. Is there any library or mehod out there to achieve this? I even tried making my own AsyncTask to do it, something like this:
public class ImageLoader extends AsyncTask<Void, Void, Bitmap> {
#Override
protected Bitmap doInBackground(Void... params) {
try {
URL url = new URL(bundle.getString("selectedImage"));
HttpURLConnection conn =
(HttpURLConnection)url.openConnection();
conn.setReadTimeout(6000);
conn.setConnectTimeout(6000);
conn.setRequestMethod("GET");
conn.setDoInput(true);
conn.connect();
int respose = conn.getResponseCode();
InputStream is = conn.getInputStream();
BufferedInputStream bufferedInputStream = new
BufferedInputStream(is);
bitmap = BitmapFactory.decodeStream(bufferedInputStream);
return bitmap;
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
but no success. Anyone have anything to help me?

1) Try to use Volley library.
https://developer.android.com/training/volley/request.html#request-image
2) Use WebView instead ImageView

I'm not really sure what you mean by "its full original size". I haven't experienced any automagic scaling of images simply by downloading them.
Maybe you could double-check that you have an appropriate android:scaleType on the target ImageView. You can read more on the different values of the scale type property here: http://developer.android.com/reference/android/widget/ImageView.ScaleType.html
If you want to pan the image, like an "unscaled" web page in the browser (typically when the image is bigger than the screen), you might need to add further logic to manage this. Maybe it could be as easy as having a ScrollView wrap your ImageView (which then would wrap its content, of course).

The error was down to photo bucket giving me a scaled down URL instead I used flikr and on my device I get an image almost identical to my original (Picasso limit is 2048x2048) but on other devices I still seem to get a 1080 x 910 image, will investigate further but it seems the answer is not to use photo bucket

Set ImageView using URL

I have an Image on my server. The URL for the image is something like:
http://www.mydomain.com/123456uploaded_image.jpg
I am trying to set this image to my ImageView. Here is the code that I tried:
try{
String url1 = myeventimagearray[position];
URL ulrn = new URL(url1);
HttpURLConnection con = (HttpURLConnection)ulrn.openConnection();
InputStream is = (InputStream) con.getInputStream();
Bitmap bmp = BitmapFactory.decodeStream(is);
if (null != bmp)
iveventimg.setImageBitmap(bmp);
else
Log.i("Image","Not set");
} catch(Exception e) {
e.printStackTrace();
}
When I try this, my imageview is empty, i.e., it doesn't set the image view and i get this System err in my logcat:
java.lang.ClassCastException: libcore.net.http.FixedLengthInputStream cannot be cast to com.example.eventnotifier.Base64$InputStream
Base46.java is a file I found from the internet that Encodes and decodes to and from Base64 notation.
Any idea why I'm getting this System.error?
Thank you

Use URlImageViewHelper, it will take care of loading url into imageview.
Refer this
It will take care of caching, loading in background etc. by itself.

This is not an easy answer but you should use a caching system.
See https://github.com/chrisbanes/Android-BitmapCache for an excellent one!
Simply swap the ImageView for NetworkCacheableImageView and then use loadImage( "http://....", true );

You are likely getting an exception because you are trying to do network io on the main thread. Consider using a loader or an AsyncTask to load your image.
Check your logs, I bet you are printing a stack trace in the auto generated catch block.
new Thread(new Runnable() {
public void run() {
final Bitmap b = bitmap = BitmapFactory.decodeStream((InputStream)new URL(myeventimagearray[position]).getContent());
iveventimg.post(new Runnable() {
public void run() {
iveventimg.setImageBitmap(b);
}
});
}
}).start();

Use Picasso to fetch image from url. Implement 'com.squareup.picasso:picasso:2.71828' in build.gradle and in java
Picasso.get()
.load(url) // http://www.example.com/123456uploaded_image.jpg
.resize(50, 50)
.centerCrop()
.into(imageView)

Custom image viewing slows down

The problem
Hi there,
I'm developing an application where the user specifies some pictures and how long they are going to be on the screen.So sometimes he wants to create something like a small animation or viewing the images for a small amount of time.The problem is that after some time the images are not previewed when they should and we have a few ms of error.In the application that i'm developing time matters so I would like some help on what the problem might be.
The code
So let me explain how it works.I take the pictures from my web app and then I save them in a HashMap
Bitmap image = ImageOperations(url,String.valueOf(frameNum) + ".jpg");
ImageMap.put(String.valueOf(frameNum), image);
where the mathod ImageOperations is like that:
private Bitmap ImageOperations(String url, String saveFilename) {
try {
Display display = getWindowManager().getDefaultDisplay();
InputStream is = (InputStream) this.fetch(url);
Bitmap theImage = BitmapFactory.decodeStream(is);
if (theImage.getHeight() >= 700 || theImage.getWidth() >= 700) {
theImage = Bitmap.createScaledBitmap(theImage,
display.getWidth(), display.getHeight() - 140, true);
}
return theImage;
} catch (MalformedURLException e) {
e.printStackTrace();
return null;
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
So later I run a thread that updates the UI when the user specified.The method that updates it is this one.
public void setPictures(int NumOfFrame) {
if (frameArray.get(NumOfFrame - 1).frame_pic.contains("n/a") != true) {
ImagePlace.setImageBitmap(ImageMap.get(String.valueOf(NumOfFrame)));
} else {
ImagePlace.setImageDrawable(null);
}
}
After we update the image we put the thread for sleep and when runs again it updates the thread.Is there something that creates the problem?Does it have to do with Garbage collection?
Thank you in advance

Probably the issue is in increasing heap size when it loads additional images. I would suggest You to do some profiling so things will be much clearer and You'll get full picture of timings for the app.

First you are missing a null check at here:
ImageMap.get(String.valueOf(NumOfFrame))
And you do not recycle the old bitmap at here:
theImage.recycle(); // missing line
theImage = Bitmap.createScaledBitmap(theImage,
display.getWidth(), display.getHeight() - 140, true);
It may lead to outofmemory exceptions, with is most likely from your description of the problem.
Also I am not sure if BitmapFactory.decodeStream throw exception when he fails. You need to add a null point check there too.

Size image to fit WebView dimensions

An API I hit returns a URL to an image. I want to use a WebView, feed it this URL and have it display the image. However, I want the WebView to be a static 90dip x 90dip (images are square). The images are bigger than 90px. Is there a way I can tell the WebView to size the image to its own dimensions?

Have you tried it yet? Does it not work, if not what does it do instead?
I think you could use an ImageView to display the image with no problems. You can use a method like this to return to you a Drawable object from a url, which you can then set to the ImageView with setImageDrawable(img);
/***********************************************************
* This method will return the image from a URL.
* Note: This should be called from the UI thread.
***********************************************************/
public Drawable getRemoteImage(final URL aURL) {
try {
final URLConnection conn = aURL.openConnection();
conn.connect();
final BufferedInputStream bis = new BufferedInputStream(conn.getInputStream());
final Drawable d = Drawable.createFromStream(bis, "src");
bis.close();
return d;
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
ImageView's I know for a fact you can set to a static size (90dip x 90dip) and it will handle scaling the image down if need be to make it fit in that size, WebView might try to make it scrollable or something, I am not sure.

Android: How to optimize ListView with ImageView + 3 TextViews?

I've been looking everywhere to see if there is a standard way of achieving this but I find a different solution every-time.
Basically, I am trying to build a Custom ListView with an image and two-three lines of text besides it.
In order to optimize it, I understand that the following have to be used:
convertView: Basically if the view was already inflated, use it
Lazy-Loading: Do not load the content of the rows until they are called for
Background Downloading & Caching: Download images in their own threads and then update the row (and possible cache them?)
I could manage 1 and 2 but the third one is really confusing me.
Is there a best practice for this?
Thanks

Thanks to Mark for his help. This is one way of doing what he suggested (just in case some else is curious):
private class DownloadImageTask extends AsyncTask<Object, Integer, Bitmap> {
private ImageView iv;
protected Bitmap doInBackground(Object... params) {
try {
iv = (ImageView) params[0];
URL aURL = new URL("http://URLTOIMAGE/img" + params[1] + ".png" );
URLConnection conn = aURL.openConnection();
conn.connect();
InputStream is = conn.getInputStream();
BufferedInputStream bis = new BufferedInputStream(is);
Bitmap bm = BitmapFactory.decodeStream(bis);
bis.close();
is.close();
return bm;
} catch (IOException e) {
return null;
}
}
protected void onPostExecute(Bitmap result) {
iv.setImageBitmap((Bitmap) result);
}
}
And it would be used as follows:
new DownloadImageTask().execute(new Object[] {ImageViewHandle, position});
Note that this is not a working code. This was taken from a larger code base so you will have to make appropriate changes to make this work.

It may be a bit early to describe something as "best practice". AsyncTask or a thread monitoring a LinkedBlockingQueue are fine ways to offload something like image fetching.
You may be interested in my ThumbnailAdapter, which handles the background downloading and caching for you.