一个简单的购票app
要求：以石家庄地铁路线为准，要求界面显示内容包括起点站，终点站，购票数量；收费原则为地铁每三站收费一元，站数不足三站也收费一元，起点站不计。点击购票按钮，如果计算金额正确显示“购票成功”。
使用的工具是Android studio
MainActivity:package com.example.subwayticketapp;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Build;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Queue;
import java.util.Set;
public class MainActivity extends AppCompatActivity {
private Spinner startStationSpinner, endStationSpinner;
private EditText ticketCountEditText;
private Button buyTicketButton;
private TextView resultTextView;// 石家庄地铁线路信息
private static final List<String> LINE_1 = List.of("西王", "时光街", "长城桥", "和平医院", "烈士陵园", "新百广场", "解放广场", "平安大街", "北国商城", "博物院", "体育场", "北宋", "谈固", "朝晖桥", "白佛", "留村", "火炬广场", "石家庄东站", "南村", "洨河大道", "西庄", "东庄", "会展中心", "商务中心", "园博园", "福泽");
private static final List<String> LINE_2 = List.of("嘉华", "南位", "塔坛", "塔谈南", "石家庄站", "元村", "欧韵公园", "槐中路", "裕华路", "北国商城", "长安公园", "建和桥", "义堂", "庄窠·铁道大学", "柳辛庄");
private static final List<String> LINE_3 = List.of("西三庄", "高柱", "柏林庄", "市庄", "市二中", "新百广场", "东里", "槐安桥", "西三教", "石家庄站", "汇通路", "孙村", "塔冢", "东王", "南王", "位同", "东二环南路", "西仰陵", "中仰陵", "南豆", "太行南大街", "东乡");private static final Map<String, List<String>> STATION_LINES = new HashMap<>();
private static final Map<String, List<String>> GRAPH = new HashMap<>();static {// 初始化站点和线路的映射for (String station : LINE_1) {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {STATION_LINES.computeIfAbsent(station, k -> new ArrayList<>()).add("1号线");}}for (String station : LINE_2) {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {STATION_LINES.computeIfAbsent(station, k -> new ArrayList<>()).add("2号线");}}for (String station : LINE_3) {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {STATION_LINES.computeIfAbsent(station, k -> new ArrayList<>()).add("3号线");}}// 构建图buildGraph(LINE_1);buildGraph(LINE_2);buildGraph(LINE_3);
}private static void buildGraph(List<String> line) {for (int i = 0; i < line.size(); i++) {String station = line.get(i);if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {GRAPH.computeIfAbsent(station, k -> new ArrayList<>());}if (i > 0) {GRAPH.get(station).add(line.get(i - 1));}if (i < line.size() - 1) {GRAPH.get(station).add(line.get(i + 1));}}
}@Override
protected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);startStationSpinner = findViewById(R.id.startStationSpinner);endStationSpinner = findViewById(R.id.endStationSpinner);ticketCountEditText = findViewById(R.id.ticketCountEditText);buyTicketButton = findViewById(R.id.buyTicketButton);resultTextView = findViewById(R.id.resultTextView);// 获取所有站点List<String> allStations = new ArrayList<>();allStations.addAll(LINE_1);allStations.addAll(LINE_2);allStations.addAll(LINE_3);// 去除重复站点Set<String> uniqueStations = new HashSet<>(allStations);List<String> stationList = new ArrayList<>(uniqueStations);// 创建适配器ArrayAdapter<String> adapter = new ArrayAdapter<>(this, android.R.layout.simple_spinner_item, stationList);adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);// 设置适配器startStationSpinner.setAdapter(adapter);endStationSpinner.setAdapter(adapter);buyTicketButton.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {String startStation = startStationSpinner.getSelectedItem().toString();String endStation = endStationSpinner.getSelectedItem().toString();String ticketCountStr = ticketCountEditText.getText().toString();if (ticketCountStr.isEmpty()) {Toast.makeText(MainActivity.this, "请输入购票数量", Toast.LENGTH_SHORT).show();return;}int ticketCount = Integer.parseInt(ticketCountStr);int stationCount = calculateStationCount(startStation, endStation);int price = calculatePrice(stationCount);int totalPrice = price * ticketCount;resultTextView.setText("购票成功，总金额：" + totalPrice + " 元");}});
}private int calculateStationCount(String startStation, String endStation) {// 使用广度优先搜索（BFS）计算最短路径Queue<String> queue = new LinkedList<>();Set<String> visited = new HashSet<>();Map<String, Integer> distance = new HashMap<>();queue.add(startStation);visited.add(startStation);distance.put(startStation, 0);while (!queue.isEmpty()) {String current = queue.poll();if (current.equals(endStation)) {return distance.get(current);}if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {for (String neighbor : GRAPH.getOrDefault(current, new ArrayList<>())) {if (!visited.contains(neighbor)) {queue.add(neighbor);visited.add(neighbor);distance.put(neighbor, distance.get(current) + 1);}}}}return 0;
}private int calculatePrice(int stationCount) {return (int) Math.ceil((double) stationCount / 3);
}
}
layout:
<TextViewandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:text="起点站:"android:textSize="18sp" /><Spinnerandroid:id="@+id/startStationSpinner"android:layout_width="match_parent"android:layout_height="wrap_content" /><TextViewandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:text="终点站:"android:textSize="18sp" /><Spinnerandroid:id="@+id/endStationSpinner"android:layout_width="match_parent"android:layout_height="wrap_content" /><TextViewandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:text="购票数量:"android:textSize="18sp" /><EditTextandroid:id="@+id/ticketCountEditText"android:layout_width="match_parent"android:layout_height="wrap_content"android:inputType="number" /><Buttonandroid:id="@+id/buyTicketButton"android:layout_width="match_parent"android:layout_height="wrap_content"android:text="购票" /><TextViewandroid:id="@+id/resultTextView"android:layout_width="wrap_content"android:layout_height="wrap_content"android:textSize="18sp" />
