编写一个安卓的员工管理系统代码

这是一个简单的员工管理系统，包括添加、删除、修改和查询员工信息的功能。以下是代码：

MainActivity.java

import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import androidx.appcompat.app.AppCompatActivity;
import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {
    private EditText editName, editAge, editPosition, editSalary;
    private Button btnAdd, btnDelete, btnUpdate, btnSearch;
    private List<Employee> employeeList = new ArrayList<>();
    private int currentIndex = -1;

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

        editName = findViewById(R.id.edit_name);
        editAge = findViewById(R.id.edit_age);
        editPosition = findViewById(R.id.edit_position);
        editSalary = findViewById(R.id.edit_salary);

        btnAdd = findViewById(R.id.btn_add);
        btnDelete = findViewById(R.id.btn_delete);
        btnUpdate = findViewById(R.id.btn_update);
        btnSearch = findViewById(R.id.btn_search);

        btnAdd.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                addEmployee();
            }
        });

        btnDelete.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                deleteEmployee();
            }
        });

        btnUpdate.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                updateEmployee();
            }
        });

        btnSearch.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                searchEmployee();
            }
        });
    }

    private void addEmployee() {
        String name = editName.getText().toString();
        int age = Integer.parseInt(editAge.getText().toString());
        String position = editPosition.getText().toString();
        double salary = Double.parseDouble(editSalary.getText().toString());

        Employee employee = new Employee(name, age, position, salary);
        employeeList.add(employee);
        currentIndex = employeeList.size() - 1;

        Toast.makeText(this, "员工添加成功！", Toast.LENGTH_SHORT).show();
    }

    private void deleteEmployee() {
        if (currentIndex >= 0 && currentIndex < employeeList.size()) {
            employeeList.remove(currentIndex);
            currentIndex = -1;

            Toast.makeText(this, "员工删除成功！", Toast.LENGTH_SHORT).show();
        } else {
            Toast.makeText(this, "没有可删除的员工！", Toast.LENGTH_SHORT).show();
        }
    }

    private void updateEmployee() {
        if (currentIndex >= 0 && currentIndex < employeeList.size()) {
            String name = editName.getText().toString();
            int age = Integer.parseInt(editAge.getText().toString());
            String position = editPosition.getText().toString();
            double salary = Double.parseDouble(editSalary.getText().toString());

            Employee employee = new Employee(name, age, position, salary);
            employeeList.set(currentIndex, employee);

            Toast.makeText(this, "员工信息更新成功！", Toast.LENGTH_SHORT).show();
        } else {
            Toast.makeText(this, "没有可更新的员工！", Toast.LENGTH_SHORT).show();
        }
    }

    private void searchEmployee() {
        String name = editName.getText().toString();
        for (int i = 0; i < employeeList.size(); i++) {
            Employee employee = employeeList.get(i);
            if (employee.getName().equals(name)) {
                currentIndex = i;
                editAge.setText(String.valueOf(employee.getAge()));
                editPosition.setText(employee.getPosition());
                editSalary.setText(String.valueOf(employee.getSalary()));

                Toast.makeText(this, "员工信息查询成功！", Toast.LENGTH_SHORT).show();
                return;
            }
        }

        Toast.makeText(this, "没有查询到该员工的信息！", Toast.LENGTH_SHORT).show();
    }
}

Employee.java

public class Employee {
    private String name;
    private int age;
    private String position;
    private double salary;

    public Employee(String name, int age, String position, double salary) {
        this.name = name;
        this.age = age;
        this.position = position;
        this.salary = salary;
    }

    public String getName() {
        return name;
    }

    public int getAge() {
        return age;
    }

    public String getPosition() {
        return position;
    }

    public double getSalary() {
        return salary;
    }
}

activity_main.xml

<?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"
    android:padding="16dp">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="员工信息管理系统"
        android:textSize="24sp"
        android:textStyle="bold" />

    <EditText
        android:id="@+id/edit_name"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:hint="姓名" />

    <EditText
        android:id="@+id/edit_age"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:inputType="number"
        android:hint="年龄" />

    <EditText
        android:id="@+id/edit_position"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:hint="职位" />

    <EditText
        android:id="@+id/edit_salary"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:inputType="numberDecimal"
        android:hint="薪水" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:orientation="horizontal">

        <Button
            android:id="@+id/btn_add"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="添加" />

        <Button
            android:id="@+id/btn_delete"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginStart="16dp"
            android:text="删除" />

        <Button
            android:id="@+id/btn_update"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginStart="16dp"
            android:text="更新" />

        <Button
            android:id="@+id/btn_search"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginStart="16dp"
            android:text="查询" />
    </LinearLayout>
</LinearLayout>

此代码仅供参考，可能需要根据实际情况进行修改和调整。