Nested navigation graphs in Android Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a NavHostFragment in the activity layout.

Android Kotlin

val navHostFragment = supportFragmentManager.findFragmentById(R.id.[1]) as NavHostFragment

Drag options to blanks, or click blank then click option'

Anav_host_fragment

Bmain_nav_host

Cnav_graph_host

Dfragment_container

Attempts:

3 left

💡 Hint

Common Mistakes

Using an incorrect fragment ID that does not exist in the layout.

Confusing the NavHostFragment ID with other container IDs.

The NavHostFragment is usually referenced by its ID in the layout, commonly named 'nav_host_fragment'.

2fill in blank

medium

Complete the code to navigate to a nested graph destination using NavController.

Android Kotlin

navController.navigate(R.id.[1])

Drag options to blanks, or click blank then click option'

AprofileFragment

BhomeFragment

Cnested_graph

DsettingsFragment

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to navigate directly to a fragment inside the nested graph without specifying the nested graph ID.

Using a fragment ID instead of the nested graph ID.

To navigate to a nested navigation graph, you use the ID of the nested graph itself, not a fragment destination.

3fill in blank

hard

Fix the error in the nested graph XML by completing the missing attribute.

Android Kotlin

<navigation xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/[1]"
    app:startDestination="homeFragment">

Drag options to blanks, or click blank then click option'

Amain_graph

Bapp_nav_graph

Croot_graph

Dnested_graph

Attempts:

3 left

💡 Hint

Common Mistakes

Using the same ID as the main graph causing conflicts.

Omitting the android:id attribute entirely.

The nested graph must have a unique ID, commonly named 'nested_graph' to distinguish it from the main graph.

4fill in blank

hard

Fill both blanks to define a nested navigation graph with a start destination.

Android Kotlin

<navigation android:id="@+id/[1]" app:startDestination="[2]">

Drag options to blanks, or click blank then click option'

Anested_graph

BhomeFragment

CprofileFragment

Dmain_graph

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up the graph ID with fragment IDs.

Setting a start destination that does not exist in the nested graph.

The nested graph ID is 'nested_graph' and its start destination is 'homeFragment'.

5fill in blank

hard

Fill all three blanks to correctly retrieve the NavController from a nested NavHostFragment.

Android Kotlin

val navHostFragment = supportFragmentManager.findFragmentById(R.id.[1]) as [2]
val navController = navHostFragment.[3]

Drag options to blanks, or click blank then click option'

Anested_nav_host

BNavHostFragment

CnavController

Dmain_nav_host

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong fragment ID.

Casting to the wrong fragment type.

Trying to access navController without casting.

You find the nested NavHostFragment by its ID 'nested_nav_host', cast it to NavHostFragment, then get its navController property.