Develop Reference

How to display images from URL efficently

I need to display a list of images in my application, and i get those images from an API call as an URL. Now I'm using Glide to show them, but i don't like the loading effect it makes (blank space while loading, and the the image). Is there any way to instant show those images, without any loading time and possibly without downloading them?

Since the images are stored on a remote server there is no way to bypass the downloading process, however Glide makes sure to only download the image from remote server when necessary, as the docs state
By default, Glide checks multiple layers of caches before starting a
new request for an image:
Active resources - Is this image displayed in another View right now?
Memory cache - Was this image recently loaded and still in memory?
Resource - Has this image been decoded, transformed, and written to
the disk cache before? Data - Was the data this image was obtained
from written to the disk cache before? The first two steps check to
see if the resource is in memory and if so, return the image
immediately. The second two steps check to see if the image is on disk
and return quickly, but asynchronously.
If all four steps fail to find the image, then Glide will go back to
the original source to retrieve the data (the original File, Uri, Url
etc).
To resolve this,
but i don't like the loading effect it makes (blank space while
loading, and the the image)
You can instead add a default placeholder on the ImageView until the real image is downloaded. This will display a default image while your actual image is downloading and then after download completion will replace it with the actual one.
Glide
.with(context)
.load(url)
.placeholder(R.drawable.ic_placeholder) //your default placeholder resource
.into(imageView)

you can display images from url by two ways:
Without any third party library:
URL url = new URL("URL of image here");
Bitmap bitmap = BitmapFactory.decodeStream(url.openConnection().getInputStream());
imageView.setImageBitmap(bitmap);
Second way is by using Picasso

Using high definition pictures in android

I'm having some trouble when uploading high definition pictures in my app.
I have a Grid View and when I add the photo the app crashes stating that its a memory problem.
One solution I did was to decrease the size of the image through a website (https://www.befunky.com/create/resize-image/) but the image gets blurie.
Also used a solution that is present on the official Android developers' website (https://developer.android.com/topic/performance/graphics/load-bitmap.html), unsuccessfully (the app gets too slow and I have the previous result).
I've seen many applications where this is not a issue and I want to learn the way they do it correctly.

Try Picasso, it can load an image into your imageView from your drawable (or url), and its fit() method allows you to reduce the image to the lowest possible resolution, without affecting quality.
Basically, it measures the dimensions of the target ImageView and uses resize() to reduce the image size to the dimensions of your ImageView:
High quality picture in drawable folder:
Picasso.with(context)
.load(R.drawable.image)
.fit()
.into(imageView);
High quality picture from a url:
Picasso.with(context)
.load("www.url.com/image.jpg")
.fit()
.into(imageView);
You can find more details on how to use fit, resizing and scaling with Picasso here.

Glide takes long time before displaying large images

I am trying to load images (around 5mb each) into ImageView's of size 45x45 dp in a RecyclerView. Even though original image is large, doesn't Glide load a smaller version of it because target ImageView is small? So, I expect Glide to load images in just a few seconds with an average internet speed. But, it takes like 20 seconds. What is the problem?
Images are stored in firebase storage.
Glide code :
Glide.with(context).load(firebaseStorageUrl).into(imageView);

Glide needs to load the full image from the internet before it can resize it. So the download takes a long time the first time. Afterwards it can use the small image from the cahe it created if you have caching activated.

In case you don't want to load smaller files, I recommend using a Gif-drawable library for loading large images from Glide into GifDrawable(works as an ImageView).
It can load files more than 100MB very fast. It works with plain JPG, PNG and BMP too. If these are GIFs, it plays without any delay or freeze.
If drawables declared by android:src and/or android:background are GIF files then they will be automatically recognized as GifDrawables and animated. If given drawable is not a GIF then mentioned Views work like plain ImageView and ImageButton.

Glide downloads the image first, and then you have methods to retrieve the image as bitmap to resize and compress the image. However, that won't solve your problem . Possibly there are two solutions for this:
Keep a low sized image in the server.
Use a File downloader library, which helps to download images serially and asynchronously as a queue, which would help to download the file quick. FileDownloader library is a good option for this.

Use Override in Glide for load image faster.

which is best? Creating bitmap from imageview or downloading the file

we are using an app for setting wallpaper in android device, for that we are doing below steps
1) we have set of images and URLs
2) We are fetching the URL on an Imageview
so now we have to set the wallpaper, for that we need the image file, which is the best way to do it?
1) Download the file directly from URL and store it in a local storage and use it as wallpaper.
or
2) Create a bitmap from the Imageview and use it as wallpaper.
Doing the second option will reduce any quality of the image we using?
First option how to we can do it?
We have fetch the images successfully inside the application.

Always prefer to cache your image downloads so that you don't have to repeat the task. Using libraries like Picasso or Glide reduces a lot of effort is handling your images while at the same time optimizing your code.
Additionally it's best to use the original image as wallpaper rather than consuming the image view because if you have set any scale type's on your image view then your image will be cropped.

Picasso allows for hassle-free image loading in your application—often in one line of code!
Picasso.with(context).load("http://i.imgur.com/DvpvklR.png").into(imageView);

Load a downscaled image with Android-Universal-Image-Loader

I am using Android-Universal-Image-Loader to load an image into an imageView. Is it possible to show a downscaled version of the image i am loading while the original image has not yet loaded?

As suggested here, the way to achieve your goal would be prepare and download two images, one with less size to show as preview while the big one is downloading