android studio计算器的代码

以下是一个简单的 Android Studio 计算器应用的代码示例：

MainActivity.java

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

public class MainActivity extends AppCompatActivity {

    TextView resultTextView;
    int operand1;
    int operand2;
    String operator;

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

        resultTextView = findViewById(R.id.resultTextView);
    }

    public void numberClick(View view) {
        Button button = (Button) view;
        resultTextView.append(button.getText().toString());
    }

    public void operatorClick(View view) {
        Button button = (Button) view;
        operator = button.getText().toString();
        operand1 = Integer.parseInt(resultTextView.getText().toString());
        resultTextView.setText("");
    }

    public void equalsClick(View view) {
        operand2 = Integer.parseInt(resultTextView.getText().toString());
        int result = 0;
        switch (operator) {
            case "+":
                result = operand1 + operand2;
                break;
            case "-":
                result = operand1 - operand2;
                break;
            case "*":
                result = operand1 * operand2;
                break;
            case "/":
                result = operand1 / operand2;
                break;
        }
        resultTextView.setText(Integer.toString(result));
    }

    public void clearClick(View view) {
        resultTextView.setText("");
        operand1 = 0;
        operand2 = 0;
    }
}

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/resultTextView"
        android:textSize="30sp"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="16dp"/>

    <GridLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <Button
            android:text="1"
            android:layout_column="0"
            android:layout_row="0"
            android:onClick="numberClick"/>

        <Button
            android:text="2"
            android:layout_column="1"
            android:layout_row="0"
            android:onClick="numberClick"/>

        <Button
            android:text="3"
            android:layout_column="2"
            android:layout_row="0"
            android:onClick="numberClick"/>

        <Button
            android:text="+"
            android:layout_column="3"
            android:layout_row="0"
            android:onClick="operatorClick"/>

        <Button
            android:text="4"
            android:layout_column="0"
            android:layout_row="1"
            android:onClick="numberClick"/>

        <Button
            android:text="5"
            android:layout_column="1"
            android:layout_row="1"
            android:onClick="numberClick"/>

        <Button
            android:text="6"
            android:layout_column="2"
            android:layout_row="1"
            android:onClick="numberClick"/>

        <Button
            android:text="-"
            android:layout_column="3"
            android:layout_row="1"
            android:onClick="operatorClick"/>

        <Button
            android:text="7"
            android:layout_column="0"
            android:layout_row="2"
            android:onClick="numberClick"/>

        <Button
            android:text="8"
            android:layout_column="1"
            android:layout_row="2"
            android:onClick="numberClick"/>

        <Button
            android:text="9"
            android:layout_column="2"
            android:layout_row="2"
            android:onClick="numberClick"/>

        <Button
            android:text="*"
            android:layout_column="3"
            android:layout_row="2"
            android:onClick="operatorClick"/>

        <Button
            android:text="0"
            android:layout_column="1"
            android:layout_row="3"
            android:onClick="numberClick"/>

        <Button
            android:text="C"
            android:layout_column="0"
            android:layout_row="3"
            android:onClick="clearClick"/>

        <Button
            android:text="/"
            android:layout_column="3"
            android:layout_row="3"
            android:onClick="operatorClick"/>

        <Button
            android:text="="
            android:layout_column="2"
            android:layout_row="3"
            android:onClick="equalsClick"/>

    </GridLayout>

</LinearLayout>

这些代码将创建一个简单的四则运算计算器应用程序，具有数字按钮，运算符按钮和清除按钮。在用户输入操作数和运算符后，单击等号按钮将计算结果并将其显示在屏幕上。