Merge pull request #993 from android/update-navigation-to-2.4.0alpha01

updates navigation to 2.4.0-alpha01

Author: Murat Yener

NavigationAdvancedSample/app/src/androidTest/java/com/example/android/navigationadvancedsample/BottomNavigationTest.kt

@@ -112,24 +112,6 @@ class BottomNavigationTest {
         assertDeeperThirdScreen()
     }
 
-    @Test
-    fun bottomNavView_itemReselected_goesBackToStart() {
-        openThirdScreen()
-
-        assertThirdScreen()
-
-        onView(withContentDescription(R.string.sign_up))
-            .perform(click())
-
-        assertDeeperThirdScreen()
-
-        // Reselect the current item
-        openThirdScreen()
-
-        // Verify that it popped the back stack until the start destination.
-        assertThirdScreen()
-    }
-
     private fun assertSecondScreen() {
         onView(allOf(withText(R.string.title_list), isDescendantOfA(withId(R.id.action_bar))))
                 .check(matches(isDisplayed()))

NavigationAdvancedSample/app/src/main/java/com/example/android/navigationadvancedsample/MainActivity.kt

@@ -18,59 +18,43 @@ package com.example.android.navigationadvancedsample
 
 import android.os.Bundle
 import androidx.appcompat.app.AppCompatActivity
-import androidx.lifecycle.LiveData
-import androidx.lifecycle.Observer
 import androidx.navigation.NavController
+import androidx.navigation.fragment.NavHostFragment
+import androidx.navigation.ui.AppBarConfiguration
+import androidx.navigation.ui.navigateUp
 import androidx.navigation.ui.setupActionBarWithNavController
+import androidx.navigation.ui.setupWithNavController
 import com.google.android.material.bottomnavigation.BottomNavigationView
 
 /**
  * An activity that inflates a layout that has a [BottomNavigationView].
  */
 class MainActivity : AppCompatActivity() {
 
-    private var currentNavController: LiveData<NavController>? = null
+    private lateinit var navController: NavController
+    private lateinit var appBarConfiguration: AppBarConfiguration
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_main)
-        if (savedInstanceState == null) {
-            setupBottomNavigationBar()
-        } // Else, need to wait for onRestoreInstanceState
-    }
 
-    override fun onRestoreInstanceState(savedInstanceState: Bundle?) {
-        super.onRestoreInstanceState(savedInstanceState)
-        // Now that BottomNavigationBar has restored its instance state
-        // and its selectedItemId, we can proceed with setting up the
-        // BottomNavigationBar with Navigation
-        setupBottomNavigationBar()
-    }
+        val navHostFragment = supportFragmentManager.findFragmentById(
+            R.id.nav_host_container
+        ) as NavHostFragment
+        navController = navHostFragment.navController
 
-    /**
-     * Called on first creation and when restoring state.
-     */
-    private fun setupBottomNavigationBar() {
+        // Setup the bottom navigation view with navController
         val bottomNavigationView = findViewById<BottomNavigationView>(R.id.bottom_nav)
+        bottomNavigationView.setupWithNavController(navController)
 
-        val navGraphIds = listOf(R.navigation.home, R.navigation.list, R.navigation.form)
-
-        // Setup the bottom navigation view with a list of navigation graphs
-        val controller = bottomNavigationView.setupWithNavController(
-            navGraphIds = navGraphIds,
-            fragmentManager = supportFragmentManager,
-            containerId = R.id.nav_host_container,
-            intent = intent
+        // Setup the ActionBar with navController and 3 top level destinations
+        appBarConfiguration = AppBarConfiguration(
+            setOf(R.id.titleScreen, R.id.leaderboard,  R.id.register)
         )
-
-        // Whenever the selected controller changes, setup the action bar.
-        controller.observe(this, Observer { navController ->
-            setupActionBarWithNavController(navController)
-        })
-        currentNavController = controller
+        setupActionBarWithNavController(navController, appBarConfiguration)
     }
 
     override fun onSupportNavigateUp(): Boolean {
-        return currentNavController?.value?.navigateUp() ?: false
+        return navController.navigateUp(appBarConfiguration)
     }
 }

NavigationAdvancedSample/app/src/main/java/com/example/android/navigationadvancedsample/NavigationExtensions.kt

@@ -24,9 +24,12 @@
 
     <androidx.fragment.app.FragmentContainerView
         android:id="@+id/nav_host_container"
+        android:name="androidx.navigation.fragment.NavHostFragment"
         android:layout_width="match_parent"
         android:layout_height="0dp"
-        android:layout_weight="1" />
+        android:layout_weight="1"
+        app:defaultNavHost="true"
+        app:navGraph="@navigation/nav_graph" />
 
     <com.google.android.material.bottomnavigation.BottomNavigationView
         android:id="@+id/bottom_nav"

NavigationAdvancedSample/app/src/main/res/layout/activity_main.xml

@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright 2019, The Android Open Source Project
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~      http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+<navigation
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:id="@+id/nav_graph"
+    app:startDestination="@+id/home">
+
+    <include app:graph="@navigation/home"/>
+    <include app:graph="@navigation/list"/>
+    <include app:graph="@navigation/form"/>
+
+</navigation>