Android SwipeRefreshLayout – Make Your App More User-Friendly

The Android SwipeRefreshLayout is an essential part of modern Android apps when it comes to giving users the ability to manually refresh content by pulling down on the screen. This feature is particularly common in social media or email apps like Gmail, Facebook, and Twitter. In this article, we explain how you can integrate this design pattern into your app.

How SwipeRefreshLayout Works

The SwipeRefreshLayout is a special view (ViewGroup) that can only hold one scrollable child, such as a ScrollView, ListView, or RecyclerView. Its main purpose is to allow users to manually refresh the screen by swiping down. A common example of this functionality can be seen in Facebook’s Newsfeed, where users can pull down on the screen to load new posts.

Before SwipeRefreshLayout was added to the support library, it was necessary to program custom gestures to recognize a swipe down and refresh, for instance, a ListView. With SwipeRefreshLayout, this process is significantly simplified.

At the core of this functionality is the OnRefreshListener, which is triggered as soon as a user pulls down on the screen. You can then execute the desired code in the onRefresh() method to reload or refresh the content.

Project Structure for an Android SwipeRefreshLayout

Let’s take a look at the structure of an example project that contains a ListView, which, when swiped down, shuffles the list elements:

activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    
    <android.support.v4.widget.SwipeRefreshLayout
        android:id="@+id/swipeToRefresh"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        
        <ListView
            android:id="@+id/listView"
            android:layout_width="match_parent"
            android:layout_height="match_parent" />
            
    </android.support.v4.widget.SwipeRefreshLayout>
</RelativeLayout>

Here, a ListView is defined within a SwipeRefreshLayout. This layout ensures that when the list is pulled down, a refresh event is triggered.

MainActivity.java

package com.example.swipetorefresh;

import android.os.Bundle;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.app.AppCompatActivity;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Random;

public class MainActivity extends AppCompatActivity {

    ArrayList<String> arrayList = new ArrayList<>();
    SwipeRefreshLayout swipeRefreshLayout;
    ListView listView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        swipeRefreshLayout = findViewById(R.id.swipeToRefresh);
        listView = findViewById(R.id.listView);

        swipeRefreshLayout.setColorSchemeResources(R.color.colorAccent);

        arrayList.add("First Element");
        arrayList.add("Second Element");
        arrayList.add("Third Element");
        arrayList.add("Fourth Element");
        arrayList.add("Fifth Element");

        ArrayAdapter<String> adapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, arrayList);
        listView.setAdapter(adapter);

        swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
            @Override
            public void onRefresh() {
                shuffleList();
                swipeRefreshLayout.setRefreshing(false);
            }
        });
    }

    private void shuffleList() {
        Collections.shuffle(arrayList, new Random(System.currentTimeMillis()));
        ArrayAdapter<String> adapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, arrayList);
        listView.setAdapter(adapter);
    }
}

In this code snippet, we have created an ArrayList containing five different strings. This list is passed to an ArrayAdapter and attached to the ListView. The method shuffleList() is called whenever a swipe refresh event is triggered, and it randomly shuffles the list elements.

Key elements of the code:

• setRefreshing(false): This method notifies the SwipeRefreshLayout that the refresh has been completed, and the loading animation should stop.
• setColorSchemeResources(): This method changes the color of the refresh animation to the app’s accent color.

Conclusion

The Android SwipeRefreshLayout is a useful tool to enhance the user experience of your app. It offers an easy way to integrate a manual refresh function into your Android app. By combining ListView, RecyclerView, or other scrollable views with the SwipeRefreshLayout, you can provide your users with an intuitive way to refresh content.