Android to create alert dialog and passing event to activity

Here is the full source code to create an AlertDialog and add Buttons using the setPositiveButton and setNegativeButton methods and how to send a click on those Buttons back to the Activity by implementing an interface and making our MainActivity a Listener

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.application.exampleapplication.MainActivity">

    <TextView
        android:id="@+id/counter_text"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="0"
        android:textSize="60sp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="8dp"
        android:layout_marginTop="0dp"
        android:layout_marginRight="8dp"
        android:text="open dialog"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toBottomOf="@id/counter_text" />

</android.support.constraint.ConstraintLayout>

ExampleDialog.java

package com.example.application.exampleapplication;

import android.app.Dialog;
import android.content.Context;
import android.content.DialogInterface;
import android.os.Bundle;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatDialogFragment;


public class ExampleDialog extends AppCompatDialogFragment {
    private ExampleDialogListener listener;

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
        builder.setTitle("Attention!")
                .setMessage("Do you want to increase the counter by 1?")
                .setNegativeButton("cancel", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialogInterface, int i) {

                    }
                })
                .setPositiveButton("yes", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialogInterface, int i) {
                        listener.onYesClicked();
                    }
                });
        return builder.create();
    }

    public interface ExampleDialogListener {
        void onYesClicked();
    }

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);

        try {
            listener = (ExampleDialogListener) context;
        } catch (ClassCastException e) {
            throw new ClassCastException(context.toString()
                    + "must implement ExampleDialogListener");
        }
    }
}

MainActivity.java

package com.example.application.exampleapplication;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity implements ExampleDialog.ExampleDialogListener {
    private TextView counterText;
    private Button button;
    private int counter;

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

        counterText = (TextView) findViewById(R.id.counter_text);
        button = (Button) findViewById(R.id.button);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                openDialog();
            }
        });
    }

    public void openDialog() {
        ExampleDialog dialog = new ExampleDialog();
        dialog.show(getSupportFragmentManager(), "example dialog");
    }

    @Override
    public void onYesClicked() {
        counter++;
        counterText.setText("" + counter);
    }
}

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