It's actually capable of downloading any kind of files, not just images. You may let your download happen silently and invisible to the user, or you can enable the user to see the download in the notification area. You can also register a BroadcastReceiver to get notified after you download is complete. The setup is pretty much straightforward, refer to the linked project for sample code. Using the DownloadManager is generally not a good idea if you also want to display the image, since you'd need to read and decode the saved file instead of just setting the downloaded Bitmap into an ImageView.
Now the introduction of the great stuff - the libraries. I will start with Volley , a powerful library created by Google and covered by the official documentation.
While being a general-purpose networking library not specializing on images, Volley features quite a powerful API for managing images. You will need to implement a Singleton class for managing Volley requests and you are good to go.
You might want to replace your ImageView with Volley's NetworkImageView , so the download basically becomes a one-liner:. If you need more control, this is what it looks like to create an ImageRequest with Volley:. It is worth mentioning that Volley features an excellent error handling mechanism by providing the VolleyError class that helps you to determine the exact cause of an error.
If your app does a lot of networking and managing images isn't its main purpose, then Volley it a perfect fit for you. Square's Picasso is a well-known library which will do all of the image loading stuff for you. Just displaying an image using Picasso is as simple as:. For more control you can implement the Target interface and use it to load your image into - this will provide callbacks similar to the Volley example. Check the demo project for examples. Picasso also lets you apply transformations to the downloaded image and there are even other libraries around that extend those API.
Universal Image Loader is an another very popular library serving the purpose of image management. It uses its own ImageLoader that once initialized has a global instance which can be used to download images in a single line of code:.
The opts argument in this example is a DisplayImageOptions object. Refer to the demo project to learn more. Note : the author has mentioned that he is no longer maintaining the project as of Nov 27th, But since there are many contributors, we can hope that the Universal Image Loader will live on. Facebook's Fresco is the newest and IMO the most advanced library that takes image management to a new level: from keeping Bitmaps off the java heap prior to Lollipop to supporting animated formats and progressive JPEG streaming.
To learn more about ideas and techniques behind Fresco, refer to this post. The basic usage is quite simple. Note that you'll need to call Fresco. Initializing Fresco more than once may lead to unpredictable behavior and OOM errors. Fresco uses Drawee s to display images, you can think of them as of ImageView s:. As you can see, a lot of stuff including transformation options gets already defined in XML, so all you need to do to display an image is a one-liner:.
Fresco provides an extended customization API, which, under circumstances, can be quite complex and requires the user to read the docs carefully yes, sometimes you need to RTFM. Note that the following text reflects my personal opinion and should not be taken as a postulate.
In case you missed that, the Github link for the demo project. I have just came from solving this problem on and I would like to share the complete code that can download, save to the sdcard and hide the filename and retrieve the images and finally it checks if the image is already there.
I cannot see them in Windows Explorer either. Am I supposed to identify them as images somewhere in my code so that the file system knows it's an image? Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Downloaded image showing in android studio but not gallery Ask Question. Asked 3 years, 1 month ago. All the images and videos would be showing under Gallery.
If there is such file then delete it. Switch off and switch on the device. That's it. Improve this answer. Community Bot 1. Vishal Vishal 91 1 1 silver badge 2 2 bronze badges. The solution to your problem requires two steps: You have to delete. All your photos and videos will now be listed in the Gallery and respective apps. Parag Parag 11 1 1 bronze badge. Himanshu Lohia Himanshu Lohia 1. Eclair Apr 23, Goyal39 , Apr 23, : you could see them in collection and then downloads.
R , Apr 23, :. Goyal39 , Apr 23, : may I pls see the screenshot. KitKat Apr 23, If it is, delete it. Cupcake May 3, R , May 3, :.
In the Settings section, you need to find out the option Apps or Application Management and tap on it to display all the installed Apps on your device.
Step 3. Now you need to find the Gallery option from the listed applications and click on it to enter its App info page. On this page, you can see several options.
Just tap on Clear cache and Clear data to remove the useless data from your device. It is possible that you have saved the photos in a. So now, if you want to see them in the Gallery as usual, you need to delete them from the Nomedia folder or rename the folder to make them visible in Gallery.
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