How to create our own Listener interface in android?

This example demonstrate about How to create our own Listener interface in android

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"
   android:orientation = "vertical"
   android:layout_width = "match_parent"
   android:gravity = "center"
   android:layout_height = "match_parent">
   <TextView
      android:id = "@+id/text"
      android:layout_width = "match_parent"
      android:layout_height = "wrap_content"
      android:text = "click"
      android:textSize = "30sp" />
</LinearLayout>

In the above code, we have taken text view to show listener data.

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

package com.example.myapplication;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.view.View;
import android.widget.TextView;
public class MainActivity extends FragmentActivity implements sampleInterFace {
   sampleInterFace interFace;
   TextView textView;
   @Override
   public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      textView = findViewById(R.id.text);
      this.interFace = (sampleInterFace) this;
      interFace.sample("sairamkrishna Mammahe");
   }
   @Override
   public void sample(String text) {
      textView.setText(text);
   }
}
interface sampleInterFace {
   public void sample(String text);
}

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 android studio, open one of your project's activity files and click Run  icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen –