RecyclerView is the improvised version of a ListView in Android. It was first introduced in Marshmallow. Recycler view in Android is the class that extends ViewGroup and implements Scrolling Interface. It can be used either in the form of ListView or in the form of Grid View.
How to use RecyclerView as GridView?
While implementing Recycler view in Android we generally have to set layout manager to display our Recycler View. There are two types of layout managers for Recycler View to implement.
- Linear Layout Manager
- Grid Layout Manager
Linear Layout Manager
In linear layout manager, we can align our recycler view in a horizontal or vertical scrolling manner by specifying its orientation as vertical or horizontal.
Grid Layout Manager
In Grid Layout manager we can align our recycler in the form of a grid. Here we have to mention the number of columns that are to be displayed in the Grid of Recycler View.
Difference Between RecyclerView and GridView
1) View Holder Implementation.
In GridView it was not mandatory to use View holder implementation but in RecyclerView it is mandatory to use View Holder implementation for Recycler View. It makes the code complex but many difficulties that are faced in GridView are solved in RecyclerView.
2) Performance of Recycler View.
RecyclerView is an improvised version of ListView. The performance of Recycler View has improvised. In Recycler View the items which are ahead and behind the visible entries.
Example of GridLayoutManager in RecyclerView
A sample image is given below to get an idea about what we are going to do in this article. Note that we are going to implement this project using the Java language.
Step by Step Implementation
Step 1: Create a New Project in Android Studio
To create a new project in Android Project just refer to this article on How to Create new Project in Android Studio and make sure that the language is Java. To implement Recycler View three sub-parts are needed which are helpful to control RecyclerView. These three subparts include:
- Card Layout: The card layout is an XML file that will represent each individual grid item inside your Recycler view.
- View Holder: View Holder Class is the java class that stores the reference to the UI Elements in the Card Layout and they can be modified dynamically during the execution of the program by the list of data.
- Data Class: Data Class is an object class that holds information to be displayed in each recycler view item that is to be displayed in Recycler View.
Step 2: Create a Card Layout for Recycler View Card Items
Go to the app > res > layout> right-click > New >Layout Resource File and name the file as card_layout. In this file, all XML code related to card items in the RecyclerView is written. Below is the code for the card_layout.xml file.
Step 3: Create a Java class for Modal Data
Go to the app > java > Right-Click on your app’s package name > New > Java Class and name the file as RecyclerData. This class will handles data for each Recycler item that is to be displayed. Below is the code for the RecyclerData.java file.
Step 4: Create a new java class for the Adapter
Similarly, create a new Java Class and name the file as RecyclerViewAdapter. The adapter is the main class that is responsible for RecyclerView. It holds all methods which are useful in RecyclerView.
Note: View Holder Class is also implemented in Adapter Class itself.
These methods to handle Recycler View includes:
- onCreateViewHolder: This method inflates card layout items for Recycler View.
- onBindViewHolder: This method sets the data to specific views of card items. It also handles methods related to clicks on items of Recycler view.
- getItemCount: This method returns the length of the RecyclerView.
Below is the code for the RecyclerViewAdapter.java file. Comments are added inside the code to understand the code in more detail.
Step 5: Working with the activity_main.xml file
This is the main screen that displays all data in the form of a grid. Here we have to implement Recycler View. Below is the code snippet of the XML layout in activity_main.xml file.
Step 6: Working with the MainActivity.java file
This is the main java file where we will set LayoutManager, adapter, and set data to RecyclerView which is to be displayed in RecyclerView. Below is the code for the MainActivity.java file. Comments are added inside the code to understand the code in more detail.
You can check out the GitHub repo mentioned below where you can get all code to implement Recycler View with Grid Layout Manager. If you want to implement On Click Listener for Recycler Items in Grid Layout then check out this post for implementation of RecyclerView.
Link for the GitHub Repo: https://github.com/ChaitanyaMunje/GFG-GridLayout-Manager