官方介绍：Navigation 是一个框架，用于在 Android 应用中的“目标”之间导航，该框架提供一致的 API，无论目标是作为 Fragment、Activity 还是其他组件实现。
dependencies {
def nav_version = "2.3.1"
// Java language implementation
implementation "androidx.navigation:navigation-fragment:$nav_version"
implementation "androidx.navigation:navigation-ui:$nav_version"
// Kotlin
implementation "androidx.navigation:navigation-fragment-ktx:$nav_version"
implementation "androidx.navigation:navigation-ui-ktx:$nav_version"
// Feature module Support
implementation "androidx.navigation:navigation-dynamic-features-fragment:$nav_version"
// Testing Navigation
androidTestImplementation "androidx.navigation:navigation-testing:$nav_version"
}做一个登录--注册--找回密码--用户协议(Activity)界面的案例
在登录界面，用户可以点击找回密码、跳转到找回密码界面；点击注册，跳转到注册界面
- BaseFragment.kt
/**
* author : Iwen大大怪
* create : 2020/11/1 22:14
*/
abstract class BaseFragment : Fragment() {
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
val rootView = inflater.inflate(getLayoutResId(), container, false)
// 初始化View
initView(rootView)
return rootView
}
open fun initView(rootView: View) {
}
abstract fun getLayoutResId(): Int
}- LoginFragment.kt
/**
* 登录的Fragment
* author : Iwen大大怪
* create : 2020/11/1 22:04
*/
class LoginFragment: BaseFragment() {
override fun getLayoutResId(): Int {
return R.layout.fragment_login
}
}- ForgetFragment.kt
/**
* 找回密码的Fragment
* author : Iwen大大怪
* create : 2020/11/1 22:04
*/
class ForgetFragment: BaseFragment() {
override fun getLayoutResId(): Int {
return R.layout.fragment_forget
}
}- RegisterFragment.kt
/**
* 注册的Fragment
* author : Iwen大大怪
* create : 2020/11/1 22:04
*/
class RegisterFragment: BaseFragment() {
override fun getLayoutResId(): Int {
return R.layout.fragment_register
}
}- 主Activity代码
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
}
}- 布局代码-----通过 XML 添加 NavHostFragment
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<androidx.fragment.app.FragmentContainerView
android:id="@+id/fragment_container_view"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:defaultNavHost="true"
app:navGraph="@navigation/nav_config" />
</FrameLayout>请注意以下几点：
android:name 属性包含 NavHost 实现的类名称。
app:navGraph 属性将 NavHostFragment 与导航图相关联。导航图会在此 NavHostFragment 中指定用户可以导航到的所有目的地。
app:defaultNavHost="true" 属性确保您的 NavHostFragment 会拦截系统返回按钮。请注意，只能有一个默认 NavHost。如果同一布局（例如，双窗格布局）中有多个主机，请务必仅指定一个默认 NavHost。
- nav_config.xml
<?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"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/nav_config"
app:startDestination="@id/login_fragment"
tools:ignore="UnusedNavigation">
<fragment
android:id="@+id/login_fragment"
android:name="com.example.iwen.jetpacknavigation.fragment.LoginFragment">
</fragment>
<fragment
android:id="@+id/forget_fragment"
android:name="com.example.iwen.jetpacknavigation.fragment.ForgetFragment">
</fragment>
<fragment
android:id="@+id/register_fragment"
android:name="com.example.iwen.jetpacknavigation.fragment.RegisterFragment">
</fragment>
</navigation>- LoginFragment.kt
/**
* 登录的Fragment
* author : Iwen大大怪
* create : 2020/11/1 22:04
*/
class LoginFragment: BaseFragment() {
override fun getLayoutResId(): Int {
return R.layout.fragment_login
}
override fun initView(rootView: View) {
super.initView(rootView)
rootView.toRegisterPage.setOnClickListener {
// 跳转到注册界面
findNavController().navigate(R.id.to_register_fragment)
}
rootView.toForgetPage.setOnClickListener {
// 跳转到找回密码界面
findNavController().navigate(R.id.to_forget_fragment)
}
}
}- nav_config.xml
<fragment
android:id="@+id/login_fragment"
android:name="com.example.iwen.jetpacknavigation.fragment.LoginFragment">
<action
android:id="@+id/to_register_fragment"
app:destination="@id/register_fragment" />
<action
android:id="@+id/to_forget_fragment"
app:destination="@id/forget_fragment" />
</fragment>- nav_config.xml
<fragment
android:id="@+id/login_fragment"
android:name="com.example.iwen.jetpacknavigation.fragment.LoginFragment">
<action
android:id="@+id/to_register_fragment"
app:destination="@id/register_fragment" />
<action
android:id="@+id/to_forget_fragment"
app:destination="@id/forget_fragment" />
<action android:id="@+id/to_agreement_page"
app:destination="@id/agreement_activity"/>
</fragment>- nav_config.xml
<activity
android:id="@+id/agreement_activity"
android:name="com.example.iwen.jetpacknavigation.AgreementActivity" />- LoginFragment.kt
rootView.toAgreementPage.setOnClickListener {
// 跳转到找回密码界面
findNavController().navigate(R.id.to_agreement_page)
}- slide_from_right_to_left_in.xml
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
<translate
android:duration="400"
android:fromXDelta="100%p"
android:toXDelta="0" />
</set>- slide_from_right_to_left_out.xml
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
<translate
android:duration="400"
android:fromXDelta="0"
android:toXDelta="-100%p" />
</set>- 使用动画
<action
android:id="@+id/to_register_fragment"
app:destination="@id/register_fragment"
app:enterAnim="@anim/slide_from_right_to_left_in"
app:exitAnim="@anim/slide_from_right_to_left_out" />- slide_from_left_to_right_in.xml
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
<translate
android:duration="400"
android:fromXDelta="-100%p"
android:toXDelta="0" />
</set>- slide_from_left_to_right_out.xml
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
<translate
android:duration="400"
android:fromXDelta="0"
android:toXDelta="100%p" />
</set>- 使用动画
<action
android:id="@+id/to_register_fragment"
app:destination="@id/register_fragment"
app:popEnterAnim="@anim/slide_from_left_to_right_in"
app:popExitAnim="@anim/slide_from_left_to_right_out"/>- 修改主题
<resources>
<!-- Base application theme. -->
<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
<!-- Customize your theme here. -->
<item name="colorPrimary">@color/colorPrimary</item>
<item name="colorPrimaryDark">@color/colorPrimaryDark</item>
<item name="colorAccent">@color/colorAccent</item>
<item name="android:windowAnimationStyle">@style/activityAnimation</item>
</style>
<style name="activityAnimation" parent="@android:style/Animation">
<item name="android:activityOpenEnterAnimation">@anim/slide_from_right_to_left_in</item>
<item name="android:activityOpenExitAnimation">@anim/slide_from_right_to_left_out</item>
<item name="android:activityCloseEnterAnimation">@anim/slide_from_left_to_right_in</item>
<item name="android:activityCloseExitAnimation">@anim/slide_from_left_to_right_out</item>
</style>
</resources>想了解更多，可以参考我的另外一篇文章
- kotlin
Fragment.findNavController()
View.findNavController()
Activity.findNavController(viewId: Int)- java
NavHostFragment.findNavController(Fragment)
Navigation.findNavController(Activity, @IdRes int viewId)
Navigation.findNavController(View)-
NavController.navigateUp()
-
NavController.popBackStack()