RecyclerView is a UI component which allows us to create scrolling list. If we are able to we should use this one instead of a ListView because it forces us to use more efficient way of implementing a list and separates responsibilities to other classes. To implement a RecyclerView we have to create the following:. Before we do that we have to add a dependency to the build. Remember to update the library version to the most recent one.
You can check it here. Now we are able to add a RecyclerView to the layout. On the created the RecyclerView instance we have to set a LayoutManager.
Following the documentation:. A LayoutManager is responsible for measuring and positioning item views within a RecyclerView as well as determining the policy for when to recycle item views that are no longer visible to the user. So basically, it means that the LayoutManager is layouting the list in a chosen way. In the same way as any other layout. The list row layout is pretty simple — some image and a text next to it.
To make that happen we used LinearLayout with horizontal orientation. Note warning on the LinearLayout. In this case we could use android:drawableStart attribute in TextView but then the image should have proper size. ImageView on the other hand gives me more possibilities and I was able to changed the image size easily — I wanted to keep it as simple as I can.
An android:padding attribute is used in the LinearLayout. Now we should create an adapter. We have to create a class which extends RecyclerView. Adapter which as a parameters takes a class which extends RecyclerView. Another thing is to override some needed methods. What are these methods doing? The whole code in one piece looks like this. We can build the project and see the results. I believe that this is the best way to know what is going on with this pattern and what are the potential problems without using it.
As you can see onCreateViewHolder method is called and ViewHolder objects are created for a couple of first views and then the created ones are reusing and the adapter is just binding the data with the onBindViewHolder method.
Thanks to that the list is very efficient and user can scroll the list smoothly, because the most costly calls like inflating and finding views are happening inside the onCreateViewHolder method. Sign in.
Android Working with Recycler View
Submit Archive About Events droidcon. How to implement a RecyclerView? Mateusz Budzar Follow.Providing an impressive amount of extensibility and flexibility without giving up on a hint of performance, RecyclerView has effectively made older solutions such as ListView obsolete.
In Android SDK v And so the two solutions bring about a super-similar experience:. But with this slick move Google seemed to have forgotten about one important thing: the ViewPager listener!
Ugh… Could we fill in the gap, then, by ourselves? Well, as I mentioned, RecyclerView is very flexible. But what will the registered listener end up hearing? It gives you this nice set of info values for each page —. This is all unquestionably similar to the ViewPager listener, except that:. You get info regarding all currently visible pages — not just the first one. That implicitly breaks the assumption of that each page takes up the whole screen made by ViewPager, such that no more than 2 pages can be shown at one time.
But once again — never ever ever hold references to it…. The backing logic is optimized by preallocating what it needs. You guessed it: same as OnPageChangeListener. Namely, it tells you whenever a page becomes selected, immediately as it becomes so i. See for yourself! Wanna dive into the details? First, here are the main building blocks I was describing earlier, given to you in Kotlin:. VisiblePageState is what gives you all the info in onPageScroll.
RVPagerStateListener is the actual listener…. Sign in. Submit Archive About Events droidcon. It gives you this nice set of info values for each page — index : Adapter global page index view : The view associated with the page. Never hold references to itor your RecyclerView would bite you in the ass.
This is all unquestionably similar to the ViewPager listener, except that: A. So, does this actually work? In my previous post I went on and on about closing the basic features gap between a ViewPager and a RecyclerView…. Enthusiastic Android developer Wix by day, guitar shredder by night. ProAndroidDev Follow. See responses 3. More From Medium.ViewPager in Android allows the user to flip left and right through pages of data. Android ViewPager widget is found in the support library and it allows the user to swipe left or right to see an entirely new screen.
The enum above lists all the pages of the ViewPagers. There are three pages with their respective layouts. This brings an end to ViewPager in android example tutorial. You can download the Android ViewPager Project from the below link. Its great information. It is possible i can also swipe same layout with my menu item which are showing at action bar on top.
RED R. Thanks for the tutorial. For both. How to use OnItemClickListener with viewpager and get position of clicked item and displays the clicked item???
I tried a bunch of other tutorials but to no avail. I tried this one and it worked like a charm! Nice article. If i want to perform operations on each view like clickOnListener on Button where should i write the java code for it.
I am novice for Android development. Please help me out. Very helpful. But how i add more views more than three. Please help me. I am a novice in android development. Thank you! Really nice! Bundle; import android. Fragment; import android. FragmentActivity; import android. FragmentManager; import android. FragmentPagerAdapter; import android. Your email address will not be published. I would love to connect with you personally. Table of Contents 1 Android ViewPager 1.Let's say If I show you a UI like the following and ask you to design it, what would be the first thought process would come into your mind?
You might come up with a different set of ideas to do it. But the most common idea to do this would be using RecyclerView with multiple view types inside one recyclerView. But with the above given the solution, the major problem comes up is managing a lot of view types. In the above example, we have three types of views, one with a container to contain name and description of the user, second is a list of user and third is a banner.
But in a real-life example, there can be a lot of different views and not just three. So how can we design a view in an easy way without having to manage different view types? First, let us add the dependency required by the merge adapter. It is a part of recyclerView. In the app's build. For the above screen, we have three different types of Views.
RecyclerView in Android with Example
So, for that to structure the data we need to create three different data classes namely - User, MyDetail, Banner, inside the model package. Where User is used for structuring the data for a list of users. MyDetail is used for displaying the used for my user data and Banner is used for displaying the banner. User looks like. MyDetail data class looks like.
In this, we will create a data source for a list of users to display the list. For that, we will create an object of DataSource and in that. Where getUser will be used to get a list of User type, and getBanner is used for getting the banner image from the drawable folder. So, now in our use-case first we will define three different adapters. This adapter will be used for displaying MyUserDetails, basically the first section of the list.
Where, R. This adapter will be used to display the list of the user, where R. For that will create BannerAdapterwhich looks like. Now, we are done designing three different types of adapters, which are responsible for displaying the three types of views in a recyclerView. Now, to use the adapters we create in MergeAdapter, first, we will create an activity called MainActivity which will be our launcher activity as well. Now, in the R. It will look like.
How to implement a RecyclerView?
Now, in the function, we will initialize the variables and set them to adapter. This is how you can design a recyclerView with multiple view types in sequential order by using data from individual adapters. Let say, we don't want to pass the adapter in the constructor and want to add it later in the Merge Adapter. To add an adapter we use.
This will add the adapter at the last position in the list. Now, let's say that we want to add the adapter at a specific position then we will pass the position alongside it.GitHub is home to over 40 million developers working together to host and review code, manage projects, and build software together.
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Already on GitHub? Sign in to your account. My ViewPager will have its own lengthy sublist of about items for a minimum of 4 views inside the ViewPager as below.
I am stuck at implementing the ViewPager. Am I on the right track? Or there is any other way to utilise the EpoxyController1 to implement the ViewPager and its views?
Or some other better way? Is the viewpager for fragments or for views? Can you use a RecyclerView instead of a view pager? If you are just trying to implement a Carousel pattern a recyclerview works great. You can see how we do that in the sample app. That model passes on the data to the pager and the pager can initialize its subviews.
If you use a horizontal recyclerview as a carousel it can have another EpoxyController to manage its children. Again there is a carousel example in the sample app. It isn't set up as a viewpager type interaction, but that is easy to do with layoutmanager configuration. The ViewPager will be along with the TabLayout. The ViewPager is going to have fragments having a Recyclerview. Because these fragments will be reusable and would be used independently elsewhere. I haven't given a thought about using a RecyclerView because my use case has a TabLayout and a ViewPager like functionality to be implemented which I don't suppose can be effectively implemented by using a RecyclerView.
Its not a carousel kind of this.
Its supposed to be exactly like tabbed views. Can you tell me if this is the right way to solve this use case? I am afraid of memory leaks and memory usage? Will it hamper my app performance? How is the best way to accomplish this scenario? These are the samples for a better understanding.
Thanks for the examples, that makes it a lot easier to understand. There are several ways you could build this. I've actually built something similar to this with a tab bar with Epoxy.Android RecyclerView is more advanced version of ListView with improved performance and other benefits.
Using RecyclerView and CardView together, both lists and grids can be created very easily. Here is the complete information about RecyclerView and other examples.
In this tutorial we are going to learn how to render a simple RecyclerView with a custom layout. The recycler view we are going to design contains list of movies displaying the title, genre and year of release.
Before you start, make sure that you updated your Android Studio to latest version. Currently my Android Studio is updated to Android Studio 3. When it prompts to select a default activity, select Blank Activity and proceed. Open build. With the latest version of build tools, Android Studio is creating two layout files for each activity. Open colors. Open dimens. The RecyclerView adapter is same as ListView but the override methods are different. Create a class named Movie. This layout file renders a single row in recycler view by displaying movie name, genre and year of release.
Now create a class named MoviesAdapter. In onBindViewHolder method the appropriate movie data title, genre and year set to each row. Now open MainActivity. Here prepareMovieData method adds sample data to list view. You can add the divider line between rows by using DividerItemDecoration provided by support library. Add item decoration on RecyclerView as shown below. The default divide occupies the full width of item row.
In some scenarios you might wanna add margin to divider line. For that you need to create a custom divider class by providing necessary margins and divider color. Create a class named MyDividerItemDecoration. Open MainActivity.
Below margin of 16dp is added on left and right side of divider line. If you want to display the RecyclerView in Horizontal manner, you can do that just by changing a single line of code. All you have to do is provide direction to layout manager i.
You need to write your own class extending RecyclerView. Create a class named RecyclerTouchListener. You can notice that ClickListener interface also added here. Run the app and verify the item click. You should able to see a toast message upon clicking on a row.
You can also notice that a background ripple effect when testing on lollipop device. I hope this article gave you very good knowledge on basics of RecyclerView. Android working with Card View and Recycler View.It is a container for displaying large datasets which can be scrolled efficiently by maintaining limited number of views.
You can use RecyclerView widget when you have data collections whose elements change at runtime depend on network event or user action. In this tutorial, you will learn: What is RecyclerView? These classes are abstract and are extended to different implementations to suite a use-case. TextView, for example, has a simple purpose of displaying text content on the screen. EditText extends from the same View class and adds more functionality to enable the user to input data.
It's possible to create our own custom views to be able to achieve more flexibility when developing user interfaces. The View class provides methods we can override to draw on the screen and a means to pass in parameters such as width, height, and our own custom attributes we would want to add to our View to make it behave as we would wish.Android Development Tutorial - Recycler View in Recycler View like Google Play
ViewGroups The ViewGroup class is a kind of View but, unlike the simple View class whose responsibility is simply displaying, the ViewGroup gives us the ability put multiple views into one view, which we can reference as a whole. In this case, the View that's created at the top level that we add other simple views we can also add viewGroups to is called the "parent," and the views that are added inside are "children". We can have different rules for interaction inside the View.
For example, TextViews following each other should be have 12dp distance while ImageViews followed by TextView should have a distance of 5dp. This would be the case if we were developing our own ViewGroup from scratch. To make these configurations easier, Android provides a class called LayoutParams, which we can use to input these configurations. Android documentation provides some default parameters we would implement when configuring our own ViewGroup.
Some common parameters are ones that pertain width, height and margin. Android comes with default Views and ViewGroups we can use to do a lot of the common tasks we need. One example we've mentioned is a TextView. That's a simple view that comes with configurable aspects such as height, width, textSize, and the like.
Android also has custom ViewGroups that we can add our Views to and get the expected behavior. LinearLayout LinearLayout allows us to add View items in it. LinearLayout is an orientation attribute that dictates how it will be laid out on the screen. It also has LinearLayout.