Androidstudio计算器

如果你想开发一个简单的Android Studio计算器，可以按照以下步骤：

1. 创建一个新的Android Studio项目。

2. 在项目的`res/layout`目录下创建一个新的布局文件，例如`activity_calculator.xml`，用于展示计算器的UI界面。

3. 在布局文件中添加一个`TextView`，用于展示计算结果，以及添加多个`Button`，用于输入数字和运算符。

4. 在项目的`MainActivity`中实现计算器的逻辑。可以使用`setOnClickListener`方法为每个按钮添加点击事件，并在事件处理程序中实现计算器的逻辑。

5. 运行应用程序，测试计算器功能是否正常。

以下是一个简单的Android Studio计算器示例代码：

activity_calculator.xml：

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

    <TextView
        android:id="@+id/tv_result"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="16dp"
        android:gravity="right"
        android:textSize="32sp" />

    <GridLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_below="@id/tv_result"
        android:rowCount="5"
        android:columnCount="4">

        <Button
            android:id="@+id/btn_1"
            android:layout_column="0"
            android:layout_row="3"
            android:text="1" />

        <Button
            android:id="@+id/btn_2"
            android:layout_column="1"
            android:layout_row="3"
            android:text="2" />

        <Button
            android:id="@+id/btn_3"
            android:layout_column="2"
            android:layout_row="3"
            android:text="3" />

        <Button
            android:id="@+id/btn_add"
            android:layout_column="3"
            android:layout_row="3"
            android:text="+" />

        <Button
            android:id="@+id/btn_4"
            android:layout_column="0"
            android:layout_row="2"
            android:text="4" />

        <Button
            android:id="@+id/btn_5"
            android:layout_column="1"
            android:layout_row="2"
            android:text="5" />

        <Button
            android:id="@+id/btn_6"
            android:layout_column="2"
            android:layout_row="2"
            android:text="6" />

        <Button
            android:id="@+id/btn_subtract"
            android:layout_column="3"
            android:layout_row="2"
            android:text="-" />

        <Button
            android:id="@+id/btn_7"
            android:layout_column="0"
            android:layout_row="1"
            android:text="7" />

        <Button
            android:id="@+id/btn_8"
            android:layout_column="1"
            android:layout_row="1"
            android:text="8" />

        <Button
            android:id="@+id/btn_9"
            android:layout_column="2"
            android:layout_row="1"
            android:text="9" />

        <Button
            android:id="@+id/btn_multiply"
            android:layout_column="3"
            android:layout_row="1"
            android:text="*" />

        <Button
            android:id="@+id/btn_clear"
            android:layout_column="0"
            android:layout_row="0"
            android:layout_columnSpan="2"
            android:text="C" />

        <Button
            android:id="@+id/btn_0"
            android:layout_column="2"
            android:layout_row="4"
            android:text="0" />

        <Button
            android:id="@+id/btn_equal"
            android:layout_column="3"
            android:layout_row="4"
            android:text="=" />

        <Button
            android:id="@+id/btn_divide"
            android:layout_column="3"
            android:layout_row="0"
            android:text="/" />

    </GridLayout>

</RelativeLayout>

MainActivity.java：

public class MainActivity extends AppCompatActivity {

    private TextView tvResult;
    private Button btn1, btn2, btn3, btn4, btn5, btn6, btn7, btn8, btn9, btn0;
    private Button btnAdd, btnSubtract, btnMultiply, btnDivide, btnClear, btnEqual;

    private String currentNumber = "";
    private String lastNumber = "";
    private String currentOperator = "";

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

        tvResult = findViewById(R.id.tv_result);

        btn1 = findViewById(R.id.btn_1);
        btn2 = findViewById(R.id.btn_2);
        btn3 = findViewById(R.id.btn_3);
        btn4 = findViewById(R.id.btn_4);
        btn5 = findViewById(R.id.btn_5);
        btn6 = findViewById(R.id.btn_6);
        btn7 = findViewById(R.id.btn_7);
        btn8 = findViewById(R.id.btn_8);
        btn9 = findViewById(R.id.btn_9);
        btn0 = findViewById(R.id.btn_0);

        btnAdd = findViewById(R.id.btn_add);
        btnSubtract = findViewById(R.id.btn_subtract);
        btnMultiply = findViewById(R.id.btn_multiply);
        btnDivide = findViewById(R.id.btn_divide);
        btnClear = findViewById(R.id.btn_clear);
        btnEqual = findViewById(R.id.btn_equal);

        btn1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                currentNumber += "1";
                tvResult.setText(currentNumber);
            }
        });

        btn2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                currentNumber += "2";
                tvResult.setText(currentNumber);
            }
        });

        btn3.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                currentNumber += "3";
                tvResult.setText(currentNumber);
            }
        });

        btn4.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                currentNumber += "4";
                tvResult.setText(currentNumber);
            }
        });

        btn5.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                currentNumber += "5";
                tvResult.setText(currentNumber);
            }
        });

        btn6.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                currentNumber += "6";
                tvResult.setText(currentNumber);
            }
        });

        btn7.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                currentNumber += "7";
                tvResult.setText(currentNumber);
            }
        });

        btn8.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                currentNumber += "8";
                tvResult.setText(currentNumber);
            }
        });

        btn9.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                currentNumber += "9";
                tvResult.setText(currentNumber);
            }
        });

        btn0.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                currentNumber += "0";
                tvResult.setText(currentNumber);
            }
        });

        btnAdd.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                performCalculation();
                currentOperator = "+";
            }
        });

        btnSubtract.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                performCalculation();
                currentOperator = "-";
            }
        });

        btnMultiply.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                performCalculation();
                currentOperator = "*";
            }
        });

        btnDivide.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                performCalculation();
                currentOperator = "/";
            }
        });

        btnClear.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                currentNumber = "";
                lastNumber = "";
                currentOperator = "";
                tvResult.setText("");
            }
        });

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

    private void performCalculation() {
        if (!currentNumber.equals("") && !lastNumber.equals("") && !currentOperator.equals("")) {
            double result = 0;
            double num1 = Double.parseDouble(lastNumber);
            double num2 = Double.parseDouble(currentNumber);

            switch (currentOperator) {
                case "+":
                    result = num1 + num2;
                    break;
                case "-":
                    result = num1 - num2;
                    break;
                case "*":
                    result = num1 * num2;
                    break;
                case "/":
                    result = num1 / num2;
                    break;
            }

            lastNumber = String.valueOf(result);
            currentNumber = "";
            currentOperator = "";
            tvResult.setText(lastNumber);
        } else if (!currentNumber.equals("")) {
            lastNumber = currentNumber;
            currentNumber = "";
        }
    }
}

这只是一个简单的示例代码，你可以根据自己的需求和想法进行更改和扩展。