Flutter-新闻客户端-09-详情页展示分享远程真机调试

B 站视频

https://www.bilibili.com/vide…
https://www.bilibili.com/vide…

本节目标

• 详情页技术方案比较
• 载入 web 内容
• 自动计算高度
• 清除广告、推荐
• 拦截请求
• loading 状态显示
• 分享插件
• 远程 android 设备调试

详情展示

技术方案选择

分析工具 UI automator view

• 文件位置

/Users/ducafecat/Library/Android/sdk/tools/bin/uiautomatorviewer

淘宝方案

混合方式

头条

混合方式

什么值得买

单一 webView

技术点分析

• 1. webView 原生 混合方式
• 1. 计算 web 页面高度
• 1. 拦截请求，自定义指令
• 1. 内存占用（尽量少的 dom 元素）

安装插件

• webview_flutter

https://pub.flutter-io.cn/pac…

• pubspec.yaml

dependencies:
  webview_flutter: ^0.3.20+2

• ios/Runner/Info.plist

    <key>io.flutter.embedded_views_preview</key>
    <true/>

构建界面代码

  // 顶部导航
  Widget _buildAppBar() {return Container();
  }

  // 页标题
  Widget _buildPageTitle() {return Container();
  }

  // 页头部
  Widget _buildPageHeader() {return Container();
  }

  // web 内容
  Widget _buildWebView() {return Container();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(appBar: _buildAppBar(),
        body: SingleChildScrollView(
              child: Column(
                children: <Widget>[_buildPageTitle(),
                  Divider(height: 1),
                  _buildPageHeader(),
                  _buildWebView(),],
              ),
            ),
          );
  }

url 载入

  Widget _buildWebView() {
    return Container(
      height: _webViewHeight,
      child: WebView(
        initialUrl:
            '$SERVER_API_URL/news/content/${widget.item.id}', //widget.url,
        javascriptMode: JavascriptMode.unrestricted,
        onWebViewCreated: (WebViewController webViewController) async {_controller.complete(webViewController);
        },
        gestureNavigationEnabled: true,
      ),
    );
  }

计算高度

• PX DP

  • https://blog.akanelee.me/2018…

• 设备像素密度

  一个逻辑像素占用多少个实际像素

  • https://developer.mozilla.org…
  • https://api.flutter.dev/flutt…
• 注册 js

  double _webViewHeight = 200;

        javascriptChannels: <JavascriptChannel>[_invokeJavascriptChannel(context),
        ].toSet(),

  // 注册 js 回调
  JavascriptChannel _invokeJavascriptChannel(BuildContext context) {
    return JavascriptChannel(
        name: 'Invoke',
        onMessageReceived: (JavascriptMessage message) {print(message.message);
          var webHeight = double.parse(message.message);
          if (webHeight != null) {setState(() {_webViewHeight = webHeight;});
          }
        });
  }

• 回调

        onPageFinished: (String url) {_getWebViewHeight();
          setState(() {_isPageFinished = true;});
        },

  // 获取页面高度
  _getWebViewHeight() async {await (await _controller.future)?.evaluateJavascript('''
        try {// Invoke.postMessage([document.body.clientHeight,document.documentElement.clientHeight,document.documentElement.scrollHeight]);
          let scrollHeight = document.documentElement.scrollHeight;
          if (scrollHeight) {Invoke.postMessage(scrollHeight);
          }
        } catch {}
        ''');
  }

清除广告、推荐

• https://cn.engadget.com/cn-20…
• 删除广告

        onPageStarted: (String url) {Timer(Duration(seconds: 1), () {setState(() {_isPageFinished = true;});
           _removeAd();
           _getViewHeight();});
        },

  _removeWebViewAd() async {await (await _controller.future)?.evaluateJavascript('''
        try {function removeElement(elementName){let _element = document.getElementById(elementName);
            if(!_element) {_element = document.querySelector(elementName);
            }
            if(!_element) {return;}
            let _parentElement = _element.parentNode;
            if(_parentElement){_parentElement.removeChild(_element);
            }
          }

          removeElement('module-engadget-deeplink-top-ad');
          removeElement('module-engadget-deeplink-streams');
          removeElement('footer');
        } catch{}
        ''');
  }

拦截请求

• 页面中 href

<div class="tags">
  <a href="/tag/chrome-os" class="tag">chrome os</a>
  <a href="/tag/chromebook" class="tag">chromebook</a>
  <a href="/tag/computer" class="tag">computer</a>
  <a href="/tag/gear" class="tag">gear</a>
  <a href="/tag/google" class="tag">google</a>
  <a href="/tag/laptop" class="tag">laptop</a>
  <a href="/tag/personal computing" class="tag">personal computing</a>
  <a href="/tag/personalcomputing" class="tag">personalcomputing</a>
  <a href="/tag/pixelbook-go" class="tag">pixelbook go</a>
</div>

• navigation 拦截

        navigationDelegate: (NavigationRequest request) {if (request.url != '$SERVER_API_URL/news/content/${widget.item.id}') {toastInfo(msg: request.url);
            return NavigationDecision.prevent;
          }
          return NavigationDecision.navigate;
        },

loading 状态显示

  bool _isPageFinished = false;

  @override
  Widget build(BuildContext context) {
    return Scaffold(appBar: _buildAppBar(),
        body: Stack(
          children: <Widget>[
            SingleChildScrollView(
              child: Column(
                children: <Widget>[_buildPageTitle(),
                  Divider(height: 1),
                  _buildPageHeader(),
                  _buildWebView(),],
              ),
            ),
            _isPageFinished == true
                ? Container()
                : Align(
                    alignment: Alignment.center,
                    child: LoadingBouncingGrid.square(),),
          ],
        ));
  }

分享

安装插件

dependencies:
  share: ^0.6.4

代码

            onPressed: () {Share.share('${widget.item.title} ${widget.item.url}');
            },

真机调试

• scrcpy

https://github.com/Genymobile…

资源

视频

• b 站
• 油管镜像

蓝湖设计稿（加微信给授权 ducafecat）

https://lanhuapp.com/url/lYuz1
密码: gSKl

蓝湖现在收费了，所以查看标记还请自己上传 xd 设计稿
商业设计稿文件不好直接分享, 可以加微信联系 ducafecat

YAPI 接口管理

http://yapi.demo.qunar.com/

代码

https://github.com/ducafecat/…

参考

https://pub.flutter-io.cn/pac…
https://pub.flutter-io.cn/pac…
https://pub.flutter-io.cn/pac…
https://github.com/Genymobile…

VSCode 插件

• Flutter、Dart
• Flutter Widget Snippets
• Awesome Flutter Snippets
• Paste JSON as Code
• bloc
• Code Spell Checker