目录

1. 基本思路
<https://blog.csdn.net/weixin_42534940/article/details/81416977#1.%20%E5%9F%BA%E6%9C%AC%E6%80%9D%E8%B7%AF>

2. 代码结构如下:
<https://blog.csdn.net/weixin_42534940/article/details/81416977#2.%20%E4%BB%A3%E7%A0%81%E7%BB%93%E6%9E%84%E5%A6%82%E4%B8%8B%EF%BC%9A>

3. index目录
<https://blog.csdn.net/weixin_42534940/article/details/81416977#3.%20index%E7%9B%AE%E5%BD%95>

4. control目录 
<https://blog.csdn.net/weixin_42534940/article/details/81416977#4.%20control%E7%9B%AE%E5%BD%95%C2%A0>

5. 工程全局控制
<https://blog.csdn.net/weixin_42534940/article/details/81416977#5.%20%E5%B7%A5%E7%A8%8B%E5%85%A8%E5%B1%80%E6%8E%A7%E5%88%B6>


本文是基于上一篇“网页版树莓派小车控制程序”改造而成。主要也练习了一下微信小程序的开发。这里简单记录一下主要代码片段。也是趟过了许多的坑,例如:微信小程序不支持完全全屏,微信小程序不能横屏展示。所以开发过程中也用了一些非常手段。可以说这只是一个很基本的demo,所以里面很多东西,比如摄像头监控ip、页面元素定位我都使用了写死的值。特别是界面,我只是在iPhone
6上面做的实验,所以换到其他手机上时,界面就会变型了。

1. 基本思路

* 进入小程序时展示index页,可以让用户输入服务端url(模拟上一篇中在浏览器获取get请求)
* 然后跳转到实际的小车控制界面,并可以通过点击按钮实现小车控制
* 控制小车的移动,主要是在control.js中定义了界面按钮事件的响应,在响应事件的过程中实现http请求的发送
index页面如下: 



进去之后的页面如下(其中中间空白处会展示摄像头监控,不过我并没有启动,所以看不见):



2. 代码结构如下:

其中,index下面是首页,control是控制页面,res目录下存放的是图片资源



3. index目录

* index.js //index.js //获取应用实例 const app = getApp() Page({ data: { logo:
"/res/rasp-logo.png", welcome: "欢迎使用树莓小车", enterBtn: "进入", PromoteMsg: "Please
enter the server address (eg: http://x.x.x.x:8080)", reqURL: "" }, //
从输入框中获取用户输入的服务器地址信息 getURL: function (e) { this.setData({ reqURL:
e.detail.value }) }, enterClicked: function (e) { /* * 当按下进入按钮,需要做以下事情: * 1.
首先判断用户是否已经在输入框中输入完整的服务器地址 * 2. 发起一个到服务器的GET请求,并分析服务器的响应结果 * 3. 跳转到小车控制界面 */
console.log(this.data.reqURL) if (this.data.reqURL == '') { wx.showModal({
title: '提示', content: '请先输入正确的服务器地址!', }) return } // 发起到服务器的GET请求 wx.request({
url: this.data.reqURL, success: function (res) { //
在这里获取POST请求地址,以及视频流地址,然后赋值给全局变量,供control页面调用 console.log(res.data.match(/url =
\"(\S*)\"/)[1]) console.log(res.data.match(/src=\"(\S*)\"/)[1])
app.globalData.postURL = res.data.match(/url = \"(\S*)\"/)[1]
app.globalData.cameraURL = res.data.match(/src=\"(\S*)\"/)[1] // 跳转到control页面
wx.navigateTo({ url: '/pages/control/control', }) }, fail: function(res) {
wx.showModal({ title: '提示', content: '请检查输入的服务器地址!', }) } }) } })
* index.json:无数据,只有一对打括号
* index.wxml <!--index.wxml--> <view> <view class="welcome"> <view
class="logo"> <image style="width: 250rpx; height: 250rpx"
src="{{logo}}"></image> </view> <view> <text class="words">{{welcome}}</text>
</view> </view> <input class="requestURL" type="text"
placeholder="{{PromoteMsg}}" focus='1' cursor='10' confirm-type="done"
bindinput='getURL'></input> <button class='enter'
bindtap='enterClicked'>{{enterBtn}}</button> </view>
* index.wxss /**index.wxss**/ .welcome{ display: flex; margin-top: 50rpx;
flex-direction: column; align-items: center; justify-content: space-between; }
.requestURL{ margin: 50rpx 10rpx 30rpx 10rpx; border: 1px solid gray;
font-style: italic; font-size: small } .enter{ margin-right: 10rpx; width:
150rpx; height: 60rpx; font-size: small }
4. control目录 

* control.js // pages/control/control.js const app = getApp() Page({ /** *
页面的初始数据 */ data: { // Car control images "forwardBtn": "/res/forward.png",
"leftBtn": "/res/left.png", "rightBtn": "/res/right.png", "backLeftBtn":
"/res/back-left.png", "backRightBtn": "/res/back-right.png", "backBtn":
"/res/backward.png", // Camera control images "upBtn": "/res/forward.png",
"camLeftBtn": "/res/camLeft.png", "camRightBtn": "/res/camRight.png",
"downBtn": "/res/backward.png", "resetBtn": "/res/reset.png" }, carMove:
function(event) { wx.request({ url: this.data.postURL, data:
event.currentTarget.dataset.direction, method: "POST", success: function(res){
}, fail: function(res){ } }) }, carStop: function(event) { wx.request({ url:
this.data.postURL, data: "S", method: "POST", success: function (res) { },
fail: function (res) { } }) }, camMove: function(event) { wx.request({ url:
this.data.postURL, data: event.currentTarget.dataset.direction, method: "POST",
success: function (res) { }, fail: function (res) { } }) }, /** *
生命周期函数--监听页面加载 */ onLoad: function (options) { //this.data.cameraURL =
app.globalData.cameraURL this.setData({ cameraURL: app.globalData.cameraURL,
postURL: app.globalData.postURL }) console.log(this.data.cameraURL)
console.log("post url in control page: " + app.globalData.postURL) }, /** *
生命周期函数--监听页面初次渲染完成 */ onReady: function () { }, /** * 生命周期函数--监听页面显示 */ onShow:
function () { //console.log(wx.getSystemInfoSync().windowWidth)
//console.log(wx.getSystemInfoSync().windowHeight) }, /** * 生命周期函数--监听页面隐藏 */
onHide: function () { }, /** * 生命周期函数--监听页面卸载 */ onUnload: function () { }, /**
* 页面相关事件处理函数--监听用户下拉动作 */ onPullDownRefresh: function () { }, /** *
页面上拉触底事件的处理函数 */ onReachBottom: function () { }, /** * 用户点击右上角分享 */
onShareAppMessage: function () { } })
* control.json { "navigationBarBackgroundColor": "#ffffff",
"navigationBarTextStyle": "black", "navigationBarTitleText": "树莓小车",
"backgroundColor": "#eeeeee", "backgroundTextStyle": "light",
"enablePullDownRefresh": false, "navigationStyle": "custom", "disableScroll":
true }
* control.wxml <!--pages/control/control.wxml--> <view class='control'> <!--
This image shows the camera view --> <image class='cameraView'
src='http://192.168.1.104:8080/?action=stream' style="z-index:1"></image> <!--
The following six images control the car move --> <image class='button'
id='forward' src='{{forwardBtn}}' style="position:absolute;z-index:2"
bindtouchstart='carMove' data-direction='F' bindtouchend='carStop'></image>
<image class='button' id='left' src='{{leftBtn}}'
style="position:absolute;z-index:2" bindtouchstart='carMove' data-direction='L'
bindtouchend='carStop'></image> <image class='button' id='right'
src='{{rightBtn}}' style="position:absolute;z-index:2" bindtouchstart='carMove'
data-direction='R' bindtouchend='carStop'></image> <image class='button'
id='backLeft' src='{{backLeftBtn}}' style="position:absolute;z-index:2"
bindtouchstart='carMove' data-direction='BL' bindtouchend='carStop'></image>
<image class='button' id='backRight' src='{{backRightBtn}}'
style="position:absolute;z-index:2" bindtouchstart='carMove'
data-direction='BR' bindtouchend='carStop'></image> <image class='button'
id='back' src='{{backBtn}}' style="position:absolute;z-index:2"
bindtouchstart='carMove' data-direction='B' bindtouchend='carStop'></image>
<!-- The following images control the camera move --> <image class='button'
id='up' src='{{upBtn}}' style="position:absolute;z-index:2"
bindtouchstart='camMove' data-direction='VU'></image> <image class='button'
id='camLeft' src='{{camLeftBtn}}' style="position:absolute;z-index:2"
bindtouchstart='camMove' data-direction='HL'></image> <image class='button'
id='camRight' src='{{camRightBtn}}' style="position:absolute;z-index:2"
bindtouchstart='camMove' data-direction='HR'></image> <image class='button'
id='down' src='{{downBtn}}' style="position:absolute;z-index:2"
bindtouchstart='camMove' data-direction='VD'></image> <image class='button'
id='reset' src='{{resetBtn}}' style="position:absolute;z-index:2"
bindtouchstart='camMove' data-direction='RESET'></image> </view>
* control.wxss /* pages/control/control.wxss */ .control { width: 100%;
height: 100%; transform: rotate(90deg); background-color: #eee;
justify-content: center; } .cameraView { margin-left: 0px; width: 603px;
height: 375px; background-color: #eee; justify-content: center; } .button {
height: 60px; width: 60px; opacity: 0.3; } #forward { left: 60px; top: 135px; }
#left { left: 0px; top: 195px; } #right { left: 120px; top: 195px; } #backLeft
{ left: 0px; top: 255px; } #backRight { left: 120px; top: 255px; } #back {
left: 60px; top: 315px; } #up { left: 480px; top: 195px; } #camLeft { left:
420px; top: 255px; } #camRight { left: 540px; top: 255px; } #down { left:
480px; top: 315px; } #reset{ left: 480px; top: 135px }
5. 工程全局控制

* app.js:实际似乎并没有用到,里面都是工程创建时的默认代码 //app.js App({ onLaunch: function () { //
展示本地存储能力 var logs = wx.getStorageSync('logs') || [] logs.unshift(Date.now())
wx.setStorageSync('logs', logs) // 登录 wx.login({ success: res => { // 发送
res.code 到后台换取 openId, sessionKey, unionId } }) // 获取用户信息 wx.getSetting({
success: res => { if (res.authSetting['scope.userInfo']) { // 已经授权,可以直接调用
getUserInfo 获取头像昵称,不会弹框 wx.getUserInfo({ success: res => { // 可以将 res 发送给后台解码出
unionId this.globalData.userInfo = res.userInfo // 由于 getUserInfo 是网络请求,可能会在
Page.onLoad 之后才返回 // 所以此处加入 callback 以防止这种情况 if (this.userInfoReadyCallback) {
this.userInfoReadyCallback(res) } } }) } } }) }, globalData: { userInfo: null,
postURL: null, cameraURL: null } })
* app.json: { "pages": [ "pages/index/index", "pages/control/control" ],
"window": { "backgroundTextStyle": "light", "navigationBarBackgroundColor":
"#fff", "navigationBarTitleText": "树莓小车", "navigationBarTextStyle": "black",
"showStatusBar": false } }
* app.wxss: /**app.wxss**/ .container { height: 100%; display: flex;
flex-direction: column; align-items: center; justify-content: space-between;
padding: 200rpx 0; box-sizing: border-box; }
* project.control.json: { "description": "项目配置文件。", "packOptions": {
"ignore": [] }, "setting": { "urlCheck": false, "es6": true, "postcss": true,
"minified": true, "newFeature": true }, "compileType": "miniprogram",
"libVersion": "2.0.4", "appid": "wx18414b9f85bfc895", "projectname":
"wechat-control", "isGameTourist": false, "condition": { "search": { "current":
-1, "list": [] }, "conversation": { "current": -1, "list": [] }, "game": {
"currentL": -1, "list": [] }, "miniprogram": { "current": -1, "list": [] } } }