Navigation入门

Navigation 组件由下面3个关键部分组成：

Navigation Graph XML resource 包含与navigation有关的所有信息，如destination path等。

NavHostFragment Layout XML 添加到layout的widget，显示了Navigation Graph的destination。

NavController Kotlin/Java 对象追踪在 Navigation Graph 中的位置，协调那些destination。

Destinations

destination 是在app中可以导航到的地方，一般是fragment或activity。

一般来说，fragment作为destination。

Navigation Graph

NavController 此类用于控制在NavHostFragment中fragment的切换

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Fragment.findNavController()
View.findNavController()
Activity.findNavController(viewId: Int)

val button = view.findViewById<Button>(R.id.navigate_destination_button)
button?.setOnClickListener(
        Navigation.createNavigateOnClickListener(R.id.flow_step_one_dest, null)
)

// Note the usage of curly braces since we are defining the click listener lambda
view.findViewById<Button>(R.id.navigate_action_button)?.setOnClickListener {
    val flowStepNumberArg = 1
    val action = HomeFragmentDirections.nextAction(flowStepNumberArg)
    findNavController().navigate(action)
}

drawer

bottom

DeepLink

val args = Bundle()
args.putString("myarg", "From Widget");
val pendingIntent = NavDeepLinkBuilder(context)
        .setGraph(R.navigation.mobile_navigation)
        .setDestination(R.id.deeplink_dest)
        .setArguments(args)
        .createPendingIntent()

remoteViews.setOnClickPendingIntent(R.id.deep_link_button, pendingIntent)

backstack

Web Link with Destination

<fragment
    android:id="@+id/deeplink_dest"
    android:name="com.example.android.codelabs.navigation.DeepLinkFragment"
    android:label="@string/deeplink"
    tools:layout="@layout/deeplink_fragment">

    <argument
        android:name="myarg"
        android:defaultValue="Android!"/>

    <deepLink app:uri="www.example.com/{myarg}" />
</fragment>

<activity android:name=".MainActivity">
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.DEFAULT" />
        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>

    <nav-graph android:value="@navigation/mobile_navigation" />
</activity>

待

2020-3-25 23:11:39

hi,aoyun