从Android中的URL加载图像

Question

I'm trying to load an image from the following url: https://fangkarte.de:8080/fangfisch/file/files/592036af55dfffca0155e01fe10002f7

In Chrome/IE the image will be displayed without problems. When I try to load the image on Android I am not able to store the image as an PNG file. Everytime the image will be saved as a textfile which contains the image as base64 String.

Also I tried the following code but the decodedByte is null:

byte[] decodedString = Base64.decode(encodedImage, Base64.DEFAULT);
Bitmap decodedByte = BitmapFactory.decodeByteArray(decodedString, 0, decodedString.length);

Does anyone have an idea how I can show my image from the url as an bitmap or which I prefer to store the image on the device as an png?

Answer 1

Use Universal Image Loder to upload image from Url Download universal image loder and add to your lib folder and

Implement the below code where you want to load image

ImageLoader imageLoader = ImageLoader.getInstance();

imageLoader.init(ImageLoaderConfiguration.createDefault(context));

DisplayImageOptions options = new DisplayImageOptions.Builder().cacheInMemory(true)
        .cacheOnDisc(true).resetViewBeforeLoading(true)
        .showImageForEmptyUri(R.drawable.noimage)
        .showImageOnFail(R.drawable.icon3)
        .showImageOnLoading(R.drawable.loading).build();

imageLoader.displayImage(url, imageview, options);

Answer 2

For handling images, Use Picasso , Glide , Universal image loader, Volley or Fresco

Eg, in picasso, you will be able to load images, store them in memory cache and handle cancellations in listviews/recyclerviews etc...

Picasso.with(context).load(" https://fangkarte.de:8080/fangfisch/file/files/592036af55dfffca0155e01fe10002f7 ").placeholder("someimagetillyourimagedownloads).into(R.id.yourimageview);

Picasso: https://github.com/square/picasso

Glide: https://github.com/bumptech/glide

Fresco: https://github.com/facebook/fresco ( I use this after extensively testing all 3 except volley )

UIL: https://github.com/nostra13/Android-Universal-Image-Loader

Similar things can be done using all the above libraries.

I highly recommend not trying to handle images on your own. It can turn into quite a mess if you are a novice android dev.

Answer 3

The image you download is much to big ((860.000 bytes)) to make a Bitmap out of it. So BitmapFactory will return null.

Scale image down before use.