Dialog with a single choice String List

This post describes how to display a String list in a dialog box and select one item from it.

In activity_main.xml add a Button and a TextView.

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.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=".MainActivity">

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        android:textSize="25dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="PICK FRUIT"
        android:textSize="25dp"
        app:layout_constraintBottom_toTopOf="@+id/textView1"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>

In MainActivity.java use following code.

package com.example.dialog;

import android.content.DialogInterface;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {

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

        Button button1 = findViewById(R.id.button1);
        TextView textView = findViewById(R.id.textView1);

        button1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
                builder.setTitle("Pick a fruit");

                String[] fruits_list = {"Apple", "Mango", "Banana", "Pineapple", "Cherry", "Guava", "Papaya"};

                builder.setItems(fruits_list, new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        textView.setText(fruits_list[which]);
                    }
                });

                AlertDialog dialog = builder.create();
                dialog.show();
            }
        });

    }

}

Now run the app. It will show the dialog box with list of fruits when button is clicked. And when any fruit is selected, it will display the fruit in the TextView.

Dialog with list