title: 翻译|React-navigation导航系统(5)-Router
date: 2017-03-30 09:57:00
categories: 翻译
tags: React-Native
Routers
Router定义一个组件的navigation state,允许开发者定义路径和可以操作的actions.
内建的Routers
- StackRouter
- TabRouter
使用Routers
为了手动定制一个navigator,在组件里可以放一个静态的router.(使用内建的组件快速的定制一个navigator,使用Navigator Factory更容易实现).
class MyNavigator extends React.Component {
static router = StackRouter(routes, config);
...
}
现在你可以把这个组件作为另一个navigator的screen对待,MyNavigator的导航逻辑在StackRouter中定义.
定制化Router
看看[定制Router API 部分](https://reactnavigation.org/docs/routers/api)学习StackRouter和TabRouter的API.
只要你愿意也可以重写router的函数.
定制Navigation的Actions
为了重写navigation的行为,你可以在getStateForAction中重写navigation state的逻辑,从而手动处理routes和index.
const MyApp = StackNavigator({
Home: { screen: HomeScreen },
Profile: { screen: ProfileScreen },
}, {
initialRouteName: 'Home',
})
MyApp.router = {
...MyApp.router,
getStateForAction(action, state) {
if (state && action.type === 'PushTwoProfiles') {
const routes = [
...state.routes,
{key: 'A', routeName: 'Profile', params: { name: action.name1 }},
{key: 'B', routeName: 'Profile', params: { name: action.name2 }},
];
return {
...state,
routes,
index: routes.length - 1,
};
}
return MyApp.router.getStateForAction(action, state);
},
};
阻止某些Navigation的Actions
有时候根据你的route,需要阻止某些navigation的活动
const MyStackRouter = StackRouter({
Home: { screen: HomeScreen },
Profile: { screen: ProfileScreen },
}, {
initialRouteName: 'Home',
})
const MyAppRouter = {
...MyStackRouter,
getStateForAction(action, state) {
if (
state &&
action.type === NavigationActions.BACK &&
state.routes[state.index].params.isEditing
) {
// Returning null from getStateForAction means that the action
// has been handled/blocked, but there is not a new state
return null;
}
return MyStackRouter.getStateForAction(action, state);
},
};
操作定制URIs
或许你的app有一个独特的URI,内建的routers处理不了.你可以通过getActionForPathAndParams来扩展router.
import { NavigationActions } from 'react-navigation'
const MyApp = StackNavigator({
Home: { screen: HomeScreen },
Profile: { screen: ProfileScreen },
}, {
initialRouteName: 'Home',
})
const previousGetActionForPathAndParams = MyApp.router.getActionForPathAndParams
Object.assign(MyApp.router, {
getActionForPathAndParams(path, params) {
if (
path === 'my/custom/path' &&
params.magic === 'yes'
) {
// returns a profile navigate action for /my/custom/path?magic=yes
return NavigationActions.navigate({
routeName: 'Profile',
action: NavigationActions.navigate({
// This child action will get passed to the child router
// ProfileScreen.router.getStateForAction to get the child
// navigation state.
routeName: 'Friends',
}),
});
}
return previousGetActionForPathAndParams(path, params);
},
};
定制Router API
你可以童工下面的函数来构建自己的router对象,
const MyRouter = {
getStateForAction: (action, state) => ({}),
getActionForPathAndParams: (path, params) => null,
getPathAndParamsForState: (state) => null,
getComponentForState: (state) => MyScreen,
getComponentForRouteName: (routeName) => MyScreen,
};
// Now, you can make a navigator by putting the router on it:
class MyNavigator extends React.Component {
static router = MyRouter;
render() {
...
}
}
getStateForAction(action,state)
根据给定的action来定义返回的navigation sate.当一个action通过props.navigation.dispatch()传递,或者任何其他的助手函数被调用,例如navigation.navitate()的时候,这个函数将会运行.
通常这个函数将会以下面的形式返回navitaion state.
{
index: 1, // identifies which route in the routes array is active
routes: [
{
// Each route needs a name to identify the type.
routeName: 'MyRouteName',
// A unique identifier for this route in the routes array:
key: 'myroute-123',
// (used to specify the re-ordering of routes)
// Routes can have any data, as long as key and routeName are correct
...randomRouteData,
},
...moreRoutes,
]
}
如果router已经在外部处理了acion,或者想不改变任何的navigation state就消化它,这个函数就返回null.
getComponentForRouterName(routeName)
为给定的route name返回子组件或者navigator.
像这样声明一个routergetStateForAction输出的state.
{
index: 1,
routes: [
{ key: 'A', routeName: 'Foo' },
{ key: 'B', routeName: 'Bar' },
],
}
基于state中的额routeName,router将会调用router.getComponentForRouteName('Foo')或router.getComponentForRouteName('Bar')来返回对应的有效组件.
getComponentForState(state)
从深度嵌套navigation state返回激活的组件
getActionForPathAndParams
返回一个可选配置的navigation action,在用户导航到这个路径并且有可选的查询参数的时候使用这个action.
getPathAndParamsForState
用户在app中返回同一个URL链接的点时,这个函数返回路径和参数.
从这个函数返回的路径和参数应该是从一个action获得的,这个action是重传进入router的getActionForPathAndParams的.这个action一旦通过getStateForAction传递,会给你返回形似的state.
getScreenConfig
这个函数从一个route获取navigation的可选项.必须要提供screen的当前navigation prop和被返回的选项的名字.
-
navigation-这是screen将会使用的navigation prop,对应在screen的route和state.Dispatch将会根据screen的上下文来触发actions. -
optionName-被获取的选项的名字,例如’title’
在实例的视图内,或许你需要远程获取配置的标题
// First, prepare a navigation prop for your child, or re-use one if already available.
const childNavigation = addNavigationHelpers({
// In this case we use navigation.state.index because we want the title for the active route.
state: navigation.state.routes[navigation.state.index],
dispatch: navigation.dispatch,
})
const screenTitle = this.props.router.getScreenConfig(childNavigation, 'title');
StackRouter
管理navigation堆栈的逻辑,包括入栈,出栈,操作路径解析创建深层次的堆栈.
让我们看看简单的stack router
const MyApp = StackRouter({
Home: { screen: HomeScreen },
Profile: { screen: ProfileScreen },
}, {
initialRouteName: 'Home',
})
RouteConfig
最简单的stack router期待的参数是一个config对象,这里是示例配置
const MyApp = StackRouter({ // This is the RouteConfig:
Home: {
screen: HomeScreen,
path: '',
},
Profile: {
screen: ProfileScreen,
path: 'profile/:name',
},
Settings {
// This can be handy to lazily require a screen:
getScreen: () => require('Settings').default,
// Note: Child navigators cannot be configured using getScreen because
// the router will not be accessible. Navigators must be configured
// using `screen: MyNavigator`
path: 'settings',
},
});
每一个在config中的条目有如下内容
-
path-设定条目的路径和参数可以在stack中被解析 -
screen-设定screen组件或者子navigator -
getScreen-为screen组件设定惰性加载的设定
StackConfig
配置的选项也被传递进入stack router.
-
initalRouteName-stack首次加载的默认路由的routeName -
initialRouteParams-初始化route的默认参数 -
paths-提供routeName到path配置的映射,将会重写routeConfigs里的path设置
Supported Actions
stack router可以对下面的导航actions作为响应.如果有可能,router将会代理到子代router的action操作.
- Navigate-如果routeName和router的routerConfigs其中之一匹配,将会push一个新的route到堆栈.
- Back-返回(props)
- Reset-清除堆栈,提供一个新的actions创建新的navigation state
- SetParams-screen dispatch一个action去改变当前route的参数
TabRouter
管理应用中的一套tabs,处理tabs之间的跳转,处理back键的操作返回到初始化的tab.
看看简单的tabs router
const MyApp = TabRouter({
Home: { screen: HomeScreen },
Settings: { screen: SettingsScreen },
}, {
initialRouteName: 'Home',
})
RouteConfig
tabs router有为每一个tab的routeConfig
const MyApp = TabRouter({ // This is the RouteConfig:
Home: {
screen: HomeScreen,
path: 'main',
},
Settings: {
// This can be handy to lazily require a tab:
getScreen: () => require('./SettingsScreen').default,
// Note: Child navigators cannot be configured using getScreen because
// the router will not be accessible. Navigators must be configured
// using `screen: MyNavigator`
path: 'settings',
},
});
config中的每一个config可能有
-
config-每一个tab的path -
screen-定制screen组件或者子代navigator -
getScreen-为一个screen组件设定惰性加载的设置(navigator没有这样的配置)
Tab Router Config
被传递到router的可配置选项
-
initialRouteName-首次加载的tab的routeName -
order-tabs的顺序 -
path-提供routeName到path config的映射,映射重写routeConfig中的path设定 -
backBehavior-点击back按钮应该返回到初始化的tab吗？如果是的话,设置initialRoute,否则就是none,默认到initialRoute的行为.
Support Actions
tabs router会对下面的navigation actions做出响应.如果有可能,router将代理到子代router的action.
- Navigate-如果和tab的routeName匹配,就会跳转到对应的tab
- Back-如果不是第一个默认的tab,就跳转到第一个tab
- SetParams-screen dispatch一个Action来改变当前route的state
