알림 대화상자

activity_main.xml

<?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/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        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="Button"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.498"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.642" />

</androidx.constraintlayout.widget.ConstraintLayout>

 

 

 

MainActivity

package com.example.a15_sampledialog;

import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;

import android.content.DialogInterface;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    TextView textView;

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

        textView = findViewById(R.id.textView);

        Button button1 = findViewById(R.id.button1);

        button1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                showMsg();
            }
        });
    }

    private void showMsg() {
//        대화 상자를 만들기 위한 빌더 객체 생성
        AlertDialog.Builder builder = new AlertDialog.Builder(this);

        builder.setTitle("안내");
        builder.setMessage("종료하시겠습니까?");
        builder.setIcon(android.R.drawable.ic_dialog_alert);

//        예 버튼 추가
        builder.setPositiveButton("예", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                String msg = "예 버튼이 눌렸습니다";
                textView.setText(msg);
            }
        });

//        취소 버튼 추가
        builder.setNeutralButton("취소", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                String msg = "취소 버튼이 눌렸습니다";
                textView.setText(msg);
            }
        });

        builder.setNegativeButton("아니오", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                String msg = "아니오 버튼이 눌렸습니다";
                textView.setText(msg);
            }
        });

//        대화상자 객체 생성 후 보여주기
        AlertDialog dialog = builder.create();
        dialog.show();
    }
}