how to make an alert message in android

 

Alert box code-activity.xml

 

 

 

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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"
    app:layoutDescription="@xml/activity_main_scene"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
         />

    <Button
        android:id="@+id/button2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="43dp"
        android:onClick="showAlert"

        android:text="Button" />


</RelativeLayout>

Java coding

package com.example.test;



import androidx.appcompat.app.AppCompatActivity;

import android.app.AlertDialog;

import android.content.DialogInterface;

import android.os.Bundle;

import android.view.View;

import android.widget.Button;



import android.os.Bundle;



public class MainActivity extends AppCompatActivity {



    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        Button alertButton = findViewById(R.id.button2);

        alertButton.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                showAlert();

            }

        });

    }





    public void showAlert() {

        AlertDialog.Builder builder = new AlertDialog.Builder(this);

        builder.setTitle("Alert");

        builder.setMessage("This is an alert message");

        builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {

            @Override

            public void onClick(DialogInterface dialog, int which) {

                dialog.dismiss();

            }

        });



        AlertDialog alertDialog = builder.create();

        alertDialog.show();

    }

}