0 概述

• 本节主要介绍了如何实现对局列表和排行榜，对局列表包含对局录像的回放的实现，最重要的是掌握怎么写分页功能。

1 对局列表功能

1.1 分页配置

由于对局数量很多，不可能放在同一页上展示，因此要实现分页功能。后端的 Mybatis 分页配置:

MybatisConfig:

@Configuration
public class MybatisConfig {@Beanpublic MybatisPlusInterceptor mybatisPlusInterceptor() {MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));return interceptor;}
}

1.2 后端按页获取对局列表接口

service.impl

需要传入参数 page，表示当前要获取的是哪一页的列表。

通过 MyBatis 提供的 API 来实现分页查询的功能，查询的页面按最新对局顺序排列。

@Override
public JSONObject getRecordList(Integer page) {IPage<Record> recordIPage = new Page<>(page, 8); // 每页展示8条QueryWrapper<Record> queryWrapper = new QueryWrapper<>();queryWrapper.orderByDesc("id");List<Record> records = recordMapper.selectPage(recordIPage, queryWrapper).getRecords();List<JSONObject> items = new ArrayList<>();for (Record record : records) {JSONObject item = new JSONObject();User userA = userMapper.selectById(record.getAId());User userB = userMapper.selectById(record.getBId());item.put("a_photo", userA.getPhoto());item.put("a_username", userA.getUsername());item.put("b_photo", userB.getPhoto());item.put("b_username", userB.getUsername());item.put("record", record);String result = "Draw";if ("A".equals(record.getLoser())) result = "B Win";else if ("B".equals(record.getLoser())) result = "A Win";item.put("result", result);items.add(item);}JSONObject resp = new JSONObject();resp.put("records", items);resp.put("records_count", recordMapper.selectCount(null));return resp;
}

1.3 前端展示传回来的对局列表

写一个表格来展示每个对局的信息，先获取一页的信息进行调试:

<template><ContentField><table class="table table-striped table-hover" style="text-align: center;"><thead><tr><th>A</th><th>B</th><th>对战结果</th><th>对战时间</th><th>操作</th></tr></thead><tbody><tr v-for="record in records" :key="record.record.id"><td>s<img :src="record.a_photo" alt="" class="record-user-photo">&nbsp;<span class="record-user-username">{{ record.a_username }}</span></td><td><img :src="record.b_photo" alt="" class="record-user-photo">&nbsp;<span class="record-user-username">{{ record.b_username }}</span></td><td>{{ record.result }}</td><td>{{ record.record.createtime }}</td><td><button type="button" class="btn btn-secondary">查看录像</button></td></tr></tbody></table></ContentField>
</template><script>
import ContentField from '../../components/ContentField.vue'
import { useStore } from 'vuex';
import { ref } from 'vue';
import $ from 'jquery';export default {components: {ContentField},setup() {const store = useStore();let records = ref([]);let current_page = 1;let total_records = 0;console.log(total_records);const pull_page = page => {current_page = page;$.ajax({url: "http://127.0.0.1:3000/record/getlist/",data: {page,},type: "get",headers: {Authorization: "Bearer " + store.state.user.token,},success(resp) {records.value = resp.records;total_records = resp.records_count;},error(resp) {console.log(resp);}})}pull_page(current_page);return {records,}}
}
</script><style scoped>
img.record-user-photo {width: 4vh;border-radius: 50%;
}
</style>

1.4 录像回放功能

1.4.1 录像回放的流程

首先要明确录像回放需要哪些参数，将这些参数从后端获取后保存在前端。之后要明确前端在哪展示录像，以及如何展示录像。

• 后端传来的参数已在 1.2 节中说明，并且前端保存在 records 数组中，records 中的每个 record.record 包含了录像的具体信息，包括地图、双方玩家的操作信息、败者等。
• 前端需要开一个全局变量 record.js 进行保存，并且决定在 PlayGround 中进行录像回放，因此需要一个变量记录当前是在 pk 还是在播放 record。另外，它们共用的 GameMap.js 也需要根据是 record 还是 pk 进行相应的判断，如果是 pk 那就是前几节实现的，如果是 record 则要播放录像。

1.4.2 录像回放的实现

• 首先在前端 record.js 记录全局变量，在点击"播放录像"按钮之后，应该将对应录像的信息保存到 Game, Record，并且跳转到新的页面播放对应录像，因此需要添加对应的路由(路由中带上对应录像的 id):

  path: '/record/:recordId/',
  name: 'record_content',
  component: RecordContentView,
  meta: {requestAuth: true,
  }
  

  const open_record_content = recordId => {for (const record of records.value) {if (record.record.id === recordId) {store.commit("updateIsRecord", true);store.commit("updateGame", {map: stringTo2D(record.record.map),a_id: record.record.aid,a_sx: record.record.asx,a_sy: record.record.asy,b_id: record.record.bid,b_sx: record.record.bsx,b_sy: record.record.bsy,});store.commit("updateSteps", {a_steps: record.record.asteps,b_steps: record.record.bsteps,});store.commit("updateRecordLoser", record.record.loser);router.push({name: "record_content",params: {recordId}})break;}}
  }
  

• 在 GameMap.js 中实现录像回放:

  add_listening_events() {if (this.store.state.record.is_record) {let k = 0;const a_steps = this.store.state.record.a_steps;const b_steps = this.store.state.record.b_steps;const loser = this.store.state.record.record_loser;const [snake0, snake1] = this.snakes;const interval_id = setInterval(() => {if (k >= a_steps.length - 1) {if (loser === "all" || loser === "A") {snake0.status = "die";}if (loser === "all" || loser === "B") {snake1.status = "die";}clearInterval(interval_id);} else {snake0.set_direction(parseInt(a_steps[k]));snake1.set_direction(parseInt(b_steps[k]));}k ++ ;}, 300);} else {/* pk页面的操作 */}
  }
  

1.5 前端分页展示

分页要满足以下几点:

(1) 当前页高亮，并且返回当前页的对局列表。

(2) 展示前面2页和后面2页的信息，如果页数不存在就不展示。

(3) 点击对应编号之后会跳转到对应的页面。

<template><ContentField><nav aria-label="..."><ul class="pagination" style="float: right;"><li class="page-item" @click="click_page(-2)"><a class="page-link" href="#">前一页</a></li><li :class="'page-item ' + page.is_active" v-for="page in pages" :key="page.number" @click="click_page(page.number)"><a class="page-link" href="#">{{ page.number }}</a></li><li class="page-item" @click="click_page(-1)"><a class="page-link" href="#">后一页</a></li></ul></nav></ContentField>
</template><script>
export default {setup() {let current_page = 1;let total_records = 0;let pages = ref([]); // pages 记录当前要展示的所有页面const click_page = page => {if (page === -2) page = current_page - 1;else if (page === -1) page = current_page + 1;let max_pages = parseInt(Math.ceil(total_records / 8));if (page >= 1 && page <= max_pages) {pull_page(page);}}const udpate_pages = () => {let max_pages = parseInt(Math.ceil(total_records / 8)); // 除的是每页展示多少个录像let new_pages = [];for (let i = current_page - 2; i <= current_page + 2; i ++ ) {if (i >= 1 && i <= max_pages) {new_pages.push({number: i,is_active: i === current_page ? "active" : "",});}}pages.value = new_pages;}/* 每次 pull_page 之后都要记得 update_pages */return {pages,click_page}}
}
</script>

2 排行榜功能

2.1 排行榜的实现

排行榜相对就简单多得多了，和对局列表功能相同，就是查出来用户列表，再在前端展示即可(前端和上面的差不多，不赘述了)。

@Override
public JSONObject getRanklist(Integer page) {IPage<User> userIPage = new Page<>(page, 8);QueryWrapper<User> queryWrapper = new QueryWrapper<>();queryWrapper.orderByDesc("rating");List<User> users = userMapper.selectPage(userIPage, queryWrapper).getRecords();JSONObject resp = new JSONObject();for (User user : users) user.setPassword(""); // 记得传回去之前要把密码清空resp.put("users", users);resp.put("users_count", userMapper.selectCount(null));return resp;
}