flutter setInitialRoute: 不生效

概述

需要实现native跳转到flutter 指定的路由页面。

iOS 工程中发现 FlutterViewController  setInitialRouter 无效，在我的需求里面是： 在iOS现有工程集成flutter项目，然后可以跳转到任意的 业务页面。

在iOS 之中实例化页面有两种方式，如下：

1. 通过全局统一的方式进行实例子化：（无效）

swift 代码：

    @objc func handleButtonAction() {
        let flutterEngine = (UIApplication.shared.delegate as? AppDelegate)?.flutterEngine
        let flutterViewController = FlutterViewController(engine: flutterEngine, nibName: nil, bundle: nil)!
        flutterViewController.setInitialRoute("test1")

        self.navigationController?.pushViewController(flutterViewController, animated: true)
    }

这种方式显示效果最好，app 已启动，就会直接加载数据，是我所需要的一种，渲染效果几乎和native 一致，毫无违和感，交互非常流畅。

但是如果我想之前跳转到指定页面如：“test1” 路由页面，却发现不起作用；

2、通过全局统一pushrouter方式：（有效，效果差）

swift pushRouter：

  @objc func handleButtonAction() {
        let flutterEngine = (UIApplication.shared.delegate as? AppDelegate)?.flutterEngine
        let flutterViewController = FlutterViewController(engine: flutterEngine, nibName: nil, bundle: nil)! 
       flutterViewController.pushRoute("test1")
        self.navigationController?.pushViewController(flutterViewController, animated: true)
    }

上面代码虽然有效，但是效果不是很好，而且有明显的push 状态。所以不是我们想要的

3、通过new FlutterViewController 方式设置（有效）

    @objc func handleButtonAction2(){
        let flutterViewController = FlutterViewController()
        flutterViewController.setInitialRoute("test1")
        
        self.navigationController?.pushViewController(flutterViewController, animated: true)
    }

有效，但是每次渲染都有一闪的效果，在交互上比native差一点。

4、flutter 路由代码 

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter rokid',
      debugShowCheckedModeBanner: false,// 显示和隐藏
      theme: ThemeData(
        // This is the theme of your application.
        //
        // Try running your application with "flutter run". You'll see the
        // application has a blue toolbar. Then, without quitting the app, try
        // changing the primarySwatch below to Colors.green and then invoke
        // "hot reload" (press "r" in the console where you ran "flutter run",
        // or press Run > Flutter Hot Reload in a Flutter IDE). Notice that the
        // counter didn't reset back to zero; the application is not restarted.
        primarySwatch: Colors.blue,
      ),
      home: PlaygroundPage(title: '若琪实验室'),
      routes: <String ,WidgetBuilder>{
        "test": (_) => new PlaygroundPage(title: "我是内部路由测试test00",),
        "test1": (_) => new PlaygroundPage(title: "我是内部路由测试test01",)
    },
    );
  }
}

参考资料：

https://www.gitmemory.com/issue/flutter/flutter/29554/492593645