安卓Java简易计算器实现代码

以下是一个简单的Android Java 计算器实现代码：

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

public class MainActivity extends AppCompatActivity {

    EditText editText;
    Button button0, button1, button2, button3, button4, button5, button6, button7, button8, button9;
    Button buttonAdd, buttonSub, buttonMul, buttonDiv, buttonC, buttonCE, buttonPoint, buttonEqual;
    double value1 = Double.NaN, value2 = Double.NaN;
    boolean addition , subtraction , multiplication , division ;

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

        editText = findViewById(R.id.editText);

        button0 = findViewById(R.id.button0);
        button1 = findViewById(R.id.button1);
        button2 = findViewById(R.id.button2);
        button3 = findViewById(R.id.button3);
        button4 = findViewById(R.id.button4);
        button5 = findViewById(R.id.button5);
        button6 = findViewById(R.id.button6);
        button7 = findViewById(R.id.button7);
        button8 = findViewById(R.id.button8);
        button9 = findViewById(R.id.button9);

        buttonAdd = findViewById(R.id.buttonAdd);
        buttonSub = findViewById(R.id.buttonSub);
        buttonMul = findViewById(R.id.buttonMul);
        buttonDiv = findViewById(R.id.buttonDiv);
        buttonC = findViewById(R.id.buttonC);
        buttonCE = findViewById(R.id.buttonCE);
        buttonPoint = findViewById(R.id.buttonPoint);
        buttonEqual = findViewById(R.id.buttonEqual);

        button0.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                editText.setText(editText.getText() + "0");
            }
        });

        button1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                editText.setText(editText.getText() + "1");
            }
        });

        button2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                editText.setText(editText.getText() + "2");
            }
        });

        button3.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                editText.setText(editText.getText() + "3");
            }
        });

        button4.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                editText.setText(editText.getText() + "4");
            }
        });

        button5.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                editText.setText(editText.getText() + "5");
            }
        });

        button6.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                editText.setText(editText.getText() + "6");
            }
        });

        button7.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                editText.setText(editText.getText() + "7");
            }
        });

        button8.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                editText.setText(editText.getText() + "8");
            }
        });

        button9.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                editText.setText(editText.getText() + "9");
            }
        });

        buttonPoint.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                editText.setText(editText.getText() + ".");
            }
        });

        buttonAdd.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                compute();
                addition = true;
                editText.setText(null);
            }
        });

        buttonSub.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                compute();
                subtraction = true;
                editText.setText(null);
            }
        });

        buttonMul.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                compute();
                multiplication = true;
                editText.setText(null);
            }
        });

        buttonDiv.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                compute();
                division = true;
                editText.setText(null);
            }
        });

        buttonEqual.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                compute();
                editText.setText(String.valueOf(value1));
                value1 = Double.NaN;
            }
        });

        buttonCE.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (editText.getText().length() > 0) {
                    CharSequence currentText = editText.getText();
                    editText.setText(currentText.subSequence(0, currentText.length() - 1));
                }
            }
        });

        buttonC.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                value1 = Double.NaN;
                value2 = Double.NaN;
                editText.setText(null);
            }
        });
    }

    private void compute() {
        if (!Double.isNaN(value1)) {
            value2 = Double.parseDouble(editText.getText().toString());

            if (addition) {
                value1 += value2;
            } else if (subtraction) {
                value1 -= value2;
            } else if (multiplication) {
                value1 *= value2;
            } else if (division) {
                value1 /= value2;
            }
        } else {
            value1 = Double.parseDouble(editText.getText().toString());
        }
    }
}

此代码将创建一个基本的界面和常规的按钮，使您能够执行简单的加法，减法，乘法和除法操作。