简介

安卓开发中，Activity的使用较为简单，而Fragment则令人头疼，使用非常复杂。为了改善此种情况，Google 在2018 I/O大会上推出了JetPack，而Navigation则是和页面切换相关的。

使用方法

build.gradle中添加依赖
implementation 'android.arch.navigation:navigation-fragment:1.0.0-rc02'
添加navigation文件.
1）鼠标右键点击“res”目录，选择“New”》“Android Resource Directory”

2）选择“navigation”

3）鼠标右键点击“navigation”目录，选择“New”》“Navigation resource file”

4）通过界面拖拽或者直接编辑导航文件

<?xml version="1.0" encoding="utf-8"?>
<navigation xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/navi_main"
    app:startDestination="@id/firstFragment">

    <fragment
        android:id="@+id/firstFragment"
        android:name="com.cxyzy.navigationdemo.FirstFragment"
        android:label="FirstFragment">
        <action
            android:id="@+id/action_firstFragment_to_secondFragment"
            app:destination="@id/secondFragment" />
    </fragment>
    <fragment
        android:id="@+id/secondFragment"
        android:name="com.cxyzy.navigationdemo.SecondFragment"
        android:label="SecondFragment" >
    </fragment>
</navigation>

跳转(含传参)

override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        gotoSecondFragmentBtn.setOnClickListener {
            Navigation.findNavController(it).navigate(R.id.action_firstFragment_to_secondFragment, Bundle().apply {
                putString("name", "jenny")
                putInt("age", 18)
            })

        }
    }

接收参数(下面的navigateUp是返回的意思)

override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        arguments?.let {
            infoTextView.text = "上页传入数据：name:" + it.getString("name") + ";age:" + it.getInt("age", 0)
        }
        gotoFirstFragmentBtn.setOnClickListener {
            Navigation.findNavController(it).navigateUp()
        }
    }