Android Studio 计算器代码

以下是一个基本的 Android Studio 计算器代码，可以进行加减乘除运算：

MainActivity.java 文件：

import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    EditText etNumber1, etNumber2;
    Button btnAdd, btnSubtract, btnMultiply, btnDivide;
    TextView tvResult;

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

        etNumber1 = findViewById(R.id.etNumber1);
        etNumber2 = findViewById(R.id.etNumber2);
        btnAdd = findViewById(R.id.btnAdd);
        btnSubtract = findViewById(R.id.btnSubtract);
        btnMultiply = findViewById(R.id.btnMultiply);
        btnDivide = findViewById(R.id.btnDivide);
        tvResult = findViewById(R.id.tvResult);

        btnAdd.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                double result = Double.parseDouble(etNumber1.getText().toString()) + Double.parseDouble(etNumber2.getText().toString());
                tvResult.setText(Double.toString(result));
            }
        });

        btnSubtract.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                double result = Double.parseDouble(etNumber1.getText().toString()) - Double.parseDouble(etNumber2.getText().toString());
                tvResult.setText(Double.toString(result));
            }
        });

        btnMultiply.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                double result = Double.parseDouble(etNumber1.getText().toString()) * Double.parseDouble(etNumber2.getText().toString());
                tvResult.setText(Double.toString(result));
            }
        });

        btnDivide.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                double result = Double.parseDouble(etNumber1.getText().toString()) / Double.parseDouble(etNumber2.getText().toString());
                tvResult.setText(Double.toString(result));
            }
        });
    }
}

activity_main.xml 布局文件：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <EditText
        android:id="@+id/etNumber1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Enter number 1" />

    <EditText
        android:id="@+id/etNumber2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Enter number 2" />

    <Button
        android:id="@+id/btnAdd"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Add" />

    <Button
        android:id="@+id/btnSubtract"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Subtract" />

    <Button
        android:id="@+id/btnMultiply"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Multiply" />

    <Button
        android:id="@+id/btnDivide"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Divide" />

    <TextView
        android:id="@+id/tvResult"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Result" />

</LinearLayout>

该代码使用了四个按钮（加、减、乘、除）来计算两个输入数的结果，并在 TextView 中显示结果。注意需要在 AndroidManifest.xml 文件中添加适当的权限和配置。