How to detect scroll up and scroll down in android listView?

Android Apps/Applications Mobile Development

This example demonstrates how do I detect scroll up and down in android listView.

Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.

Step 2 − Add the following code to res/layout/activity_main.xml.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:tools="http://schemas.android.com/tools"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:orientation="vertical"
   android:gravity="center"
   android:padding="8dp"
   tools:context=".MainActivity">
<ListView
   android:id="@+id/listView"
   android:layout_width="match_parent"
   android:layout_height="match_parent"/>
</LinearLayout>

Step 3 − Add the following code to src/MainActivity.java

import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.AbsListView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.ScrollView;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
   ScrollView scrollView;
   ListView listView;
   String[] numbers = {"1","2","3","4", "5","6","7","8", "9", "X", "11", "12", "13", "14", "15", "16", "17", "18", "19", "20" , "21", "22", "23", "24", "25"};
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      scrollView = findViewById(R.id.scrollView);
      ArrayAdapter adapter = new ArrayAdapter<>(this,
      R.layout.support_simple_spinner_dropdown_item, numbers);
      listView = findViewById(R.id.listView);
      listView.setAdapter(adapter);
      listView.setOnScrollListener(new AbsListView.OnScrollListener(){
         private int lastFirstVisibleItem;
         @Override
         public void onScrollStateChanged(AbsListView view, int scrollState) {
         }
         @Override
         public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
            if(lastFirstVisibleItem<firstVisibleItem){
               Toast.makeText(getApplicationContext(), "Scrolling down the listView",
               Toast.LENGTH_SHORT).show();
            }
            if(lastFirstVisibleItem>firstVisibleItem){
               Toast.makeText(getApplicationContext(), "Scrolling up the listView",
               Toast.LENGTH_SHORT).show();
            }
            lastFirstVisibleItem=firstVisibleItem;
         }
      });
   }
}

Step 4 − Add the following code to androidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="app.com.sample">
   <application
      android:allowBackup="true"
      android:icon="@mipmap/ic_launcher"
      android:label="@string/app_name"
      android:roundIcon="@mipmap/ic_launcher_round"
      android:supportsRtl="true"
      android:theme="@style/AppTheme">
      <activity android:name=".MainActivity">
         <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
         </intent-filter>
      </activity>
   </application>
</manifest>

Let's try to run your application. I assume you have connected your actual Android Mobile device with your computer. To run the app from the android studio, open one of your project's activity files and click the Run icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen −

Azhar

Published on 30-Oct-2019 09:43:43

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