로그인 화면과 메뉴 화면 전환

activity_main

<?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">

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="로그인"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

 

 

 

activity_menu

<?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=".MenuActivity">

    <Button
        android:id="@+id/btnCustomerManagement"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="144dp"
        android:text="고객 관리"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.498"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/btnSalesManagement"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="매출 관리"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.499" />

    <Button
        android:id="@+id/btnProductManagement"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="140dp"
        android:text="상품 관리"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.498"
        app:layout_constraintStart_toStartOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

 

 

 

MenuActivity

package com.example.a22;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MenuActivity extends AppCompatActivity {

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

        Button btnCustomerManagement = findViewById(R.id.btnCustomerManagement);
        Button btnProductManagement = findViewById(R.id.btnProductManagement);
        Button btnSalesManagement = findViewById(R.id.btnSalesManagement);

        btnCustomerManagement.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent();
                intent.putExtra("menu", btnCustomerManagement.getText());

                setResult(RESULT_OK, intent);

                finish();
            }
        });

        btnProductManagement.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent();
                intent.putExtra("menu", btnProductManagement.getText());

                setResult(RESULT_OK, intent);

                finish();
            }
        });

        btnSalesManagement.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent();
                intent.putExtra("menu", btnSalesManagement.getText());

                setResult(RESULT_OK, intent);

                finish();
            }
        });

    }
}

 

 

 

 

MainActivity

package com.example.a22;

import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;

import android.content.ComponentName;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

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

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

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(getApplicationContext(), MenuActivity.class);
                startActivityForResult(intent, 1);
            }
        });

//        CmponentName을 사용한 방법
//        button.setOnClickListener(new View.OnClickListener() {
//            @Override
//            public void onClick(View v) {
//                Intent intent = new Intent();
//                ComponentName name = new ComponentName("com.example.a22", "com.example.a22.MenuActivity");
//                intent.setComponent(name);
//                startActivityForResult(intent, 1);
//            }
//        });


    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        String intentData = data.getStringExtra("menu");
        Toast.makeText(getApplicationContext(), intentData, Toast.LENGTH_LONG).show();
    }
}