사칙연산 화면 만들기

 

java>MainActivity.java

package com.example.ex03;

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

import android.graphics.Color;
import android.os.Bundle;
import android.view.ContextMenu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class Main2Activity extends AppCompatActivity {
    TextView txtResult;
    EditText num1;
    EditText num2;
    int intnum1,intnum2;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        num1=findViewById(R.id.num1);
        num2=findViewById(R.id.num2);
        txtResult=findViewById(R.id.txtResult);
        //등록
        registerForContextMenu(num1);
        registerForContextMenu(txtResult);
    }
    public void mClick(View v){
        int intnum1=Integer.parseInt(num1.getText().toString());
        int intnum2=Integer.parseInt(num2.getText().toString());
        switch (v.getId()){
            case R.id.btn1:
                int intResult=intnum1+intnum2;
                txtResult.setText("더한결과:" +intResult);
                break;
            case R.id.btn2:
                 intResult=intnum1-intnum2;
                txtResult.setText("뺀결과:" +intResult);
                break;
            case R.id.btn3:
                intResult=intnum1*intnum2;
                txtResult.setText("곱한결과:" +intResult);
                break;
            case R.id.btn4:
                double doubleResult=(double)intnum1/intnum2;
                txtResult.setText("나눈결과:" +doubleResult);
                break;
        }
    }

    @Override
    public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {
        if(v == num1){
            menu.setHeaderTitle("에디트 메뉴");
            menu.add(0,1,0,"빨강");
            menu.add(0,2,0,"파랑");
        }
        if(v == txtResult){
            menu.setHeaderTitle("텍스트 메뉴");
            menu.add(0,3,0,"빨강");
            menu.add(0,4,0,"파랑");

        }
        super.onCreateContextMenu(menu, v, menuInfo);
    }

    @Override
    public boolean onContextItemSelected(@NonNull MenuItem item) {
        switch (item.getItemId()){
            case 1:
                num2.setBackgroundColor(Color.RED);
                break;
            case 2:
                num2.setBackgroundColor(Color.BLUE);
                break;
            case 3:
                txtResult.setBackgroundColor(Color.RED);
                break;
            case 4:
                txtResult.setBackgroundColor(Color.BLUE);
                break;
        }
        return super.onContextItemSelected(item);
    }
}

 

res>layout>activity_main2.xml