地铁查询系统Android，MainActivity

package com.example.metro_info_front_end;

import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.AutoCompleteTextView;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;

import com.example.metro_info_front_end.DataModel.MetroStation;
import com.example.metro_info_front_end.api.ApiService;
import com.example.metro_info_front_end.api.RetrofitClient;

import java.util.List;

import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;

public class MainActivity extends AppCompatActivity {

    private LinearLayout llOptimalRoute; // 最优路线查询界面布局
    private LinearLayout llMetroLine; // 地铁线路查询界面布局

    private AutoCompleteTextView systemName1;
    private AutoCompleteTextView systemName2;
    private AutoCompleteTextView lineName;
    private AutoCompleteTextView departureStation;
    private AutoCompleteTextView destinationStation;

    private ApiService apiService;

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

        // 获取布局中的线性布局
        llOptimalRoute = findViewById(R.id.LL1);
        llMetroLine = findViewById(R.id.LL2);

        // 获取按钮
        Button btnOptimalRoute = findViewById(R.id.btn1);
        Button btnMetroLine = findViewById(R.id.btn2);

        // 设置按钮点击事件监听器
        btnOptimalRoute.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // 显示最优路线查询界面，隐藏地铁线路查询界面
                llOptimalRoute.setVisibility(View.VISIBLE);
                llMetroLine.setVisibility(View.GONE);
            }
        });

        btnMetroLine.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // 显示地铁线路查询界面，隐藏最优路线查询界面
                llOptimalRoute.setVisibility(View.GONE);
                llMetroLine.setVisibility(View.VISIBLE);
            }
        });

        // 获取 AutoCompleteTextView 控件
        systemName1 = findViewById(R.id.SystemName1);
        systemName2 = findViewById(R.id.SystemName2);
        lineName = findViewById(R.id.LineName);
        departureStation = findViewById(R.id.DepartureStation);
        destinationStation = findViewById(R.id.DestinationStation);

        // 设置自动完成功能适配器
        ArrayAdapter<String> cityAdapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, getCityData());
        ArrayAdapter<String> lineAdapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, getLineData());
        ArrayAdapter<String> stationAdapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, getStationData());

        systemName1.setAdapter(cityAdapter);
        systemName2.setAdapter(cityAdapter);
        lineName.setAdapter(lineAdapter);
        departureStation.setAdapter(stationAdapter);
        destinationStation.setAdapter(stationAdapter);

        // 创建 ApiService 实例
        apiService = RetrofitClient.getRetrofitInstance().create(ApiService.class);

        // 设置查询按钮点击事件监听器
        Button query1 = findViewById(R.id.query1);
        Button query2 = findViewById(R.id.query2);

        query1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // 获取用户输入的城市、出发站点和目标站点信息
                String city1 = systemName1.getText().toString();
                String departure = departureStation.getText().toString();
                String destination = destinationStation.getText().toString();

                // 在新线程中执行网络请求
                new Thread(new Runnable() {
                    @Override
                    public void run() {
                        // 创建 Retrofit 实例
                        ApiService apiService = RetrofitClient.getRetrofitInstance().create(ApiService.class);

                        // 发起网络请求获取最优路线查询结果
                        Call<List<MetroStation>> call = apiService.searchShortestPath(city1, departure, destination);
                        call.enqueue(new Callback<List<MetroStation>>() {
                            @Override
                            public void onResponse(Call<List<MetroStation>> call, Response<List<MetroStation>> response) {
                                if (response.isSuccessful() && response.body() != null) {
                                    List<MetroStation> stations = response.body();
                                    // 处理查询结果，更新界面或显示信息
                                    final StringBuilder resultBuilder = new StringBuilder();
                                    for (MetroStation station : stations) {
                                        resultBuilder.append(station.getStationName()).append("\n");
                                    }

                                    // 切换回主线程更新 UI
                                    runOnUiThread(new Runnable() {
                                        @Override
                                        public void run() {
                                            Toast.makeText(MainActivity.this, resultBuilder.toString(), Toast.LENGTH_LONG).show();
                                        }
                                    });
                                } else {
                                    // 切换回主线程提示查询失败
                                    runOnUiThread(new Runnable() {
                                        @Override
                                        public void run() {
                                            Toast.makeText(MainActivity.this, "查询失败", Toast.LENGTH_SHORT).show();
                                        }
                                    });
                                }
                            }

                            @Override
                            public void onFailure(Call<List<MetroStation>> call, Throwable t) {
                                // 切换回主线程提示网络请求失败
                                runOnUiThread(new Runnable() {
                                    @Override
                                    public void run() {
                                        Toast.makeText(MainActivity.this, "网络请求失败", Toast.LENGTH_SHORT).show();
                                    }
                                });
                            }
                        });
                    }
                }).start(); // 启动新线程
            }
        });query1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // 获取用户输入的城市、出发站点和目标站点信息
                String city1 = systemName1.getText().toString();
                String departure = departureStation.getText().toString();
                String destination = destinationStation.getText().toString();

                // 在新线程中执行网络请求
                new Thread(new Runnable() {
                    @Override
                    public void run() {
                        // 创建 Retrofit 实例
                        ApiService apiService = RetrofitClient.getRetrofitInstance().create(ApiService.class);

                        // 发起网络请求获取最优路线查询结果
                        Call<List<MetroStation>> call = apiService.searchShortestPath(city1, departure, destination);
                        call.enqueue(new Callback<List<MetroStation>>() {
                            @Override
                            public void onResponse(Call<List<MetroStation>> call, Response<List<MetroStation>> response) {
                                if (response.isSuccessful() && response.body() != null) {
                                    List<MetroStation> stations = response.body();
                                    // 处理查询结果，更新界面或显示信息
                                    final StringBuilder resultBuilder = new StringBuilder();
                                    for (MetroStation station : stations) {
                                        resultBuilder.append(station.getStationName()).append("\n");
                                    }

                                    // 切换回主线程更新 UI
                                    runOnUiThread(new Runnable() {
                                        @Override
                                        public void run() {
                                            // 获取显示结果的 TextView 控件
                                            TextView resultTextView = findViewById(R.id.resultTextView);
                                            // 将查询结果设置到 TextView 中
                                            resultTextView.setText(resultBuilder.toString());
                                        }
                                    });
                                } else {
                                    // 切换回主线程提示查询失败
                                    runOnUiThread(new Runnable() {
                                        @Override
                                        public void run() {
                                            Toast.makeText(MainActivity.this, "查询失败", Toast.LENGTH_SHORT).show();
                                        }
                                    });
                                }
                            }

                            @Override
                            public void onFailure(Call<List<MetroStation>> call, Throwable t) {
                                // 切换回主线程提示网络请求失败
                                runOnUiThread(new Runnable() {
                                    @Override
                                    public void run() {
                                        Toast.makeText(MainActivity.this, "网络请求失败", Toast.LENGTH_SHORT).show();
                                    }
                                });
                            }
                        });
                    }
                }).start(); // 启动新线程
            }
        });



        query2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // 获取用户输入的城市和线路名称信息
                String city2 = systemName2.getText().toString();
                String lineName1 = lineName.getText().toString();

                // 在新线程中执行网络请求
                new Thread(new Runnable() {
                    @Override
                    public void run() {
                        // 创建 Retrofit 实例
                        ApiService apiService = RetrofitClient.getRetrofitInstance().create(ApiService.class);

                        // 发起网络请求获取查询结果
                        Call<List<MetroStation>> call = apiService.getStationsBySystemAndLine(city2, lineName1);
                        call.enqueue(new Callback<List<MetroStation>>() {
                            @Override
                            public void onResponse(Call<List<MetroStation>> call, Response<List<MetroStation>> response) {
                                if (response.isSuccessful() && response.body() != null) {
                                    List<MetroStation> stations = response.body();
                                    // 处理查询结果，更新界面或显示信息
                                    final StringBuilder resultBuilder = new StringBuilder();
                                    for (MetroStation station : stations) {
                                        resultBuilder.append(station.getStationName()).append("\n");
                                    }

                                    // 切换回主线程更新 UI
                                    runOnUiThread(new Runnable() {
                                        @Override
                                        public void run() {
                                            // 获取显示结果的 TextView 控件
                                            TextView resultTextView = findViewById(R.id.resultTextView);
                                            // 将查询结果设置到 TextView 中
                                            resultTextView.setText(resultBuilder.toString());
                                        }
                                    });
                                } else {
                                    // 切换回主线程提示查询失败
                                    runOnUiThread(new Runnable() {
                                        @Override
                                        public void run() {
                                            Toast.makeText(MainActivity.this, "查询失败", Toast.LENGTH_SHORT).show();
                                        }
                                    });
                                }
                            }

                            @Override
                            public void onFailure(Call<List<MetroStation>> call, Throwable t) {
                                // 切换回主线程提示网络请求失败
                                runOnUiThread(new Runnable() {
                                    @Override
                                    public void run() {
                                        Toast.makeText(MainActivity.this, "网络请求失败", Toast.LENGTH_SHORT).show();
                                    }
                                });
                            }
                        });
                    }
                }).start(); // 启动新线程
            }
        });

    }

    // 模拟城市数据
    private String[] getCityData() {
        return new String[]{"石家庄"};
    }

    private String[] getLineData() {
        return new String[]{"一号线"};
    }

    private String[] getStationData() {
        return new String[]{"新百广场", "北国商城"};
    }
}