Android pull to refresh recyclerview

Add Pull To Refresh to your Android app using Kotlin

UPDATE [November 16th, 2020]: From now on, you need to add the SwipeRefreshLayout library

Pull to Refresh is used in many popular apps, apps where content updates are frequent, like news, social media e.t.c.

In Android development this gesture it’s called ‘Swipe to Refresh‘.

Add Pull To Refresh to our app

Go to your app-level build.gradle file and add the following library:

Next, in our XML layout, we have to change the parent layout to LinearLayout and add the orientation to vertical (or use ConstraintLayout).

Then, we have to add the SwipeRefreshLayout, this adds the pull to refresh gesture, and inside that, we’ll add the RecyclerView, like this:

After our layout is ready, let’s go to our file with the RecyclerView. In this example, it’s the MainActivity.kt, and set the Color Scheme for our Pull To Refresh icon.

Also, we’re going to set the setOnRefreshListener. This listener called every time we pull down to refresh.

Inside in the setOnRefreshListener listener what we do is:

• Clean our array from the previous data (line 24)
• Call backend to download the data again. In our example, it just creates a list of numbers (line 25)
• Pass the adapter to RecyclerView’s adapter (lines 26 – 27)
• Stop Pull-To-Refresh animation (line 28)

If you have any questions, please feel free to leave a comment below

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Implementing Pull to Refresh Guide

In Android, the common «pull to refresh» UX concept is not built in to a ListView/RecyclerView. However, many Android applications would like to make use of this concept for their feeds. This is useful for all sorts of feeds such as a Twitter timeline. This effect can be achieved using the SwipeRefreshLayout class

SwipeRefreshLayout is a ViewGroup that can hold only one scrollable view as a child. This can be either a ScrollView or an AdapterView such as a ListView or a RecyclerView .

Edit your app/build.gradle file to include a library:

Make sure your libraries is up to date by adding to your root gradle.file :

Just like the previous section, wrap the scrollable view, in this case a RecyclerView with a SwipeRefreshLayout in the XML layout:

Make sure to have helper methods in your RecyclerView adapter to clear items from the underlying dataset or add items to it.

Next, we need to configure the SwipeRefreshLayout during view initialization in the activity. The activity that instantiates SwipeRefreshLayout should add an OnRefreshListener to be notified whenever the swipe to refresh gesture is completed.

The SwipeRefreshLayout will notify the listener each and every time the gesture is completed again; the listener is responsible for correctly determining when to actually initiate a refresh of its content.

Next, we need to configure the SwipeRefreshLayout during view initialization in the activity:

Note that upon successful reload, we must also signal that the refresh has completed by calling setRefreshing(false) . Also note that you should clear out old items before appending the new ones during a refresh.

If you are using SwipeRefreshLayout with Android’s new Paging Library, the data sources used to provide data to the RecyclerView need to be invalidated. Review this guide for more information.

Note: ListView is an old UI component that is no longer used in modern Android applications. Only refer this guide if you intend to update some old code that still relies on ListView.

Set SwipeRefreshLayout at the Layout you want the SwipeRefresh functionality

activity_main.xml

activity_main.xml

You could use a ScrollView instead a ListView

In the activity who points to activity_main.xml, which is main_activity(in this example), this code should be enough

main_activity.java

Now just run your application!

You could check this example on GitHub.

If you aren’t able to get the swipe to refresh working, check the following tips:

Did you accidentally call setContentView twice? Ensure that inside your activity, you’ve only called setContentView once as the 2nd line of your onCreate method.

Did you invoke setRefreshing(false) after data finished loading? With the swipe to refresh control, you are responsible for notifying the system once the new data has been loaded into the list. You must make sure to invoke setRefreshing only after the data has come back and not before. This means if you are loading data from the network, calling this within the onSuccess method.

Did you clear out the old items before updating the list? Make sure that in order for the new items to be displayed that you clear the list of any old items if needed. In other words, if you are replacing items in the list with new versions, be sure to remove the old versions from the adapter first with adapter.clear();

Are you using CoordinatorLayout? If you are using a CoordinatorLayout to manage scrolling, be sure to move the app:layout_behavior=»@string/appbar_scrolling_view_behavior» property to the SwipeRefreshLayout rather than the child RecyclerView or ListView .

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Swipe To Refresh RecyclerView Android Example | Pull To Refresh

Welcome to Swipe To Refresh RecyclerView Android Example.

This Pull/swipe To Refresh RecyclerView Android Example will answer your question like “how to refresh recyclerview in android”

Swipe or pull to refresh recyclerview feature provides easy way to handle data which are updating frequently.

In this example, we will use three different lists to implement refresh facility.

One list is of cars, second is of player names and third one is of country names. I have created video for more reference.

First of all, go through the below video to show the final outcome.

Step 1. Adding Gradle File Lines

Create a new project in the android studio.

For using RecyclerView and CardView, you need to add two lines into your build.gradle(Module:app) file.

Below are those two lines,

First one is for RecyclerView and second one is for CardView.

These lines will add some classes to our projects which we can use directly in our Java files.

Step 2. Single Drawable File

Now go to app->res->drawable directory and create a new file called cardview.xml

You need to add the below code lines in this cardview.xml file.

Above lines will create the background for cardview.

It will use the gradient effect of blue colors to make attractive background for cardview.

We will use this file inside the XML layout file which we will create in the next step.

Step 3. Specific XML layout file

Now navigate to app->res->layout directory and make a new XML file.

Give this file a name like rv_child.xml and add the below code in it

We are using tag in the above file.

All the elements which are inside the tag will have the background like the cards.

In this, we have inserted one text view.

In the background of this text view, we are using an XML file which we have created in drawable folder. (cardview.xml)

All the child rows of the recyclerview will have the view created by this rv_child.xml file.

Step 4. Model For DataSet

Now make a new JAVA class and give it a name like Model.java

Write down the below code lines in Model.java file.

There is one string variable called “name” in the above class.

For this string variable, I have created two methods.

One is getter ( getName() ) and another is setter ( setName(String name) ) .

These methods will help us to maintain the data among all the child rows of the recycler view.

We will use this class and it’s objects in the Adapter class.

Step 5. Making Adapter

Time to create adapter class. Create a new JAVA class with the name Adapter.java

Adapter.java should contain the following coding lines.

Inside the constructor of the adapter class, compiler will get the arraylist with the objects of the Model.java class.

Name of this arraylist is imageModelArrayList

Now focus on the method onCreateViewHolder().

Inside this onCreateViewHolder() method, compiler will first inflate the rv_child.xml file.

Now read the method onBindViewHolder() . Inside this onBindViewHolder() method, compiler will set the text inside the text view.

To set the text inside text view, compiler will use imageModelArrayList and the methods of Model.java class.

Step 6. Final Writings of Example

Now there should be two main files when you created a new project.

Those two main files are : activity_main.xml and MainActivity.java

Inside activity_main.xml file, you have to write the below source lines

Above main XML layout file is very simple.

We need to add only RecyclerView inside this main layout file.

But we need to implement SwipeToRefresh element as the parent of the RecyclerView.

Now go to your MainActivity.java file and write the following words in it

More Details on Main File

First of all, see the below

First line is the object of RecyclerView class. Second is the arraylist with the object of the Model.java class.

Third line is the object of the Adapter class. Fourth one is integer variable.

Fifth is the object of the SwipeRefreshLayout class.

Now read the below lines

You can see that there are three string arrays are there.

All three includes the names of vehicles,players and countries respectively.

We will use all these three lists to set in the recycler view.

You can see the below lines in the onCreate() method.

Above line is populating the data inside the imageModelArrayList using populateList() method.

Below are the code lines for populateList() method.

This method will get one integer value inside it’s parameter (int number). This integer value is defining which names recyclerview should display.

If it’s value is 0 then compiler will display vehicle names, for the value 1, it will display player names and for value 2 it will display country names in the recyclerview.

Now read the following source code snippet

When the user pull or swipe down the recyclerview, compiler will run the above lines.

Here, compiler will check the value of the integer variable currentList.

If it’s value is 2 then it will set the value of currentList as -1

Then it will increment the value of currentList by 1.

After this, compiler will run the populateList() method to put data inside imageModelArrayList.

Then it will simply attach the adapter to the recycler view.

So it is all about our swipe to refresh recyclerview android example tutorial.

Swipe Down to Refresh ListView

If you want to create listview with swipe or pull down to refresh feature then read below

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Implementing Pull To Refresh In Android

Do you want to refresh the layout or screen easily? Then, use this Swipe to Refresh Layout to refresh the layout by pulling the screen from the top.

Android SwipeRefreshLayout should be used whenever the user can refresh the contents of a view via a vertical swipe gesture. The activity that instantiates this view should add an OnRefreshListener to be notified whenever the swipe to refresh gesture is completed.

The SwipeRefreshLayout will notify the listener each and every time the gesture is completed again. the listener is responsible for correctly determining when to actually initiate a refresh of its content.

If the listener determines there should not be a refresh, it must call setRefreshing(false) to cancel any visual indication of a refresh. If an activity wishes to show just the progress animation, it should call setRefreshing(true).

To disable the gesture and progress animation, call setEnabled(false) on the view.

In this tutorial, I am going to explain how to implement pull to refresh the recyclerview with examples.

Let’s getting started to coding part.

Table of Contents

Add SwipeRefreshLayout Dependency

Also, we are going to refresh the recyclerview, So we need to add recyclerview and cardview dependencies.

Already, I have created tutorials on recyclerview and cardview, check the below links to learn in detail.

Since we are using to fetch data from the API and loading image from URL using. So, add those dependencies also.

Create Layout For Pull To Refresh

To work with pull to refresh your layout, you need to wrap your views with SwipeRefreshLayout.

Setup Recyclerview With Data

As we are using recyclerview in this example, But I am not going deeper into recyclerview in this tutorial. check the below link to setup recyclerview.

Also, Check about glide, Retrofit check the below tutorials.

now, we are done for the basic recyclerview with data from API.

Setup SwipeRefreshLayout

create OnRefreshListener

We need to create OnRefreshListener to listen the pull event in activity.

inside the listener block, we need to added a method to recall the API or do whatever what to refresh the layout.

Set Listener to SwipeRefreshLayout

Once, created the listener then set it into to refresh layout.

Use setRefreshing(true) to show the Refreshing view at the Top of the screen.

After done with your operations, Use setRefreshing(false) to show the Refreshing view at the top of the screen.

That’s it. we have implemented the pull to refresh in android.

Also, check out my other post on kotlin,

Thanks for reading.

You can download this example in GITHUB.

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