Uri; import android. AsyncTask; import android. Bundle; import android. Log; import android. View; import android. OnClickListener; import android. Dhruv Dhruv 1, 7 7 gold badges 27 27 silver badges 39 39 bronze badges. Add a comment. Active Oldest Votes. Im sure you can find code on how to implement a Gallery on this page or on Google ; After you have implemented a Gallery there are several ways of automatically flipping between your images, here is an example: Using the Android Gallery as an automated slideshow.
Community Bot 1 1 1 silver badge. DecodeGnome DecodeGnome 1, 1 1 gold badge 18 18 silver badges 36 36 bronze badges. I am stuck on how to do multiple file download and read them accordingly.
Currently i can download many files but i'm not sure as i don't know how to check sdcard content. Sign up or log in Sign up using Google. Sign up using Facebook. You can find them here. In this blog, we have seen how to use the Glide library to download and show an image in an ImageView. Images are loaded from the internet and we have given access for the App to connect the internet. All the complex work of loading and handling the images are done by the Glide library.
So, without putting much effort, we learned how to handle images in our Andoird project and I am pretty sure that you will explore some more methods of Glide library. Android Online Course for Professionals. Admin MindOrks 19th May Share this blog to spread the knowledge. Share on Facebook. Share on Twitter. When talking about Android Apps , the first thing that comes to mind is variety. There are so many varieties of Android apps providing the user with beautiful dynamic UI.
One such feature is to navigate in the Android Apps using the left and right swipes as opposed to clicking on Buttons. Not only does it look more simple and elegant but also provides ease of access to the user. There are many apps that use this swipe feature to swipe through different activities in the app. For example, the popular chatting app, Snapchat, uses it to swipe through lenses, chats , and stories. ViewPager is a class in Java that is used in conjunction with Fragments.
It is mostly used for designing the UI of the app. 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.
The url comes from the database so the filename can be uniquely easily using id. Why do you really need your own code to download it? How about just passing your URI to Download manager? I have a simple solution which is working perfectly. The code is not mine, I found it on this link. Here are the steps to follow:.
It needs a context, better to use the pass in the application context by getApplicationContext. This method can be dumped into your Activity class or other util classes.
This private class need to be placed in your Activity class as a subclass. After the image is downloaded, in the onPostExecute method, it calls the saveImage method defined above to save the image. The AsyncTask for downloading the image is defined, but we need to execute it in order to run that AsyncTask.
To do so, write this line in your onCreate method in your Activity class, or in an onClick method of a button or other places you see fit. IMO this solves the issue! If you want further steps such as load the image you can follow these extra steps:. After the image is downloaded, we need a way to load the image bitmap from the internal storage, so we can use it.
This method takes two paramethers, a context and an image file name, without the full path, the context.
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