Mobile App Fragments and Navigation

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Questions and Answers

Which statement accurately describes an Android Fragment?

A Fragment manages the entire screen and is not reusable.
A Fragment represents a reusable portion of an application's UI and must be hosted by an activity or another fragment. (correct)
Fragments can exist independently without being hosted by an activity or another fragment.
Fragments must be hosted by an activity but cannot be hosted by another fragment.

What is the primary benefit of using fragments to structure a UI?

It allows for easier modification of an activity's appearance at runtime. (correct)
It automatically optimizes the app's performance.
It reduces the complexity of managing activity lifecycles.
It simplifies the process of handling background tasks.

During which activity lifecycle state(s) can fragments be dynamically added, replaced, or removed?

While the activity is in the 'Started' lifecycle state or higher. (correct)
Only during the 'Resumed' lifecycle state.
Only before the activity is initially created.
Only during the 'Created' lifecycle state.

What is the correct sequence of steps to create a fragment?

Create a fragment layout, create a Java class extending Fragment, add the fragment to an activity. (C) Signup and view all the answers

In the context of Android app navigation, what is a 'Host'?

A UI element that contains the current navigation destination; it swaps destinations in and out as the user navigates. (B) Signup and view all the answers

Which component is responsible for managing navigation between destinations, handling deep links, and managing the back stack?

Controller (C) Signup and view all the answers

How does 'deep linking' enhance app navigation?

It takes the user directly to a specific destination from outside the app. (D) Signup and view all the answers

What is the role of a Navigation Graph in Android navigation?

It is a data structure that defines all the navigation destinations within the app and how they connect. (D) Signup and view all the answers

How can a NavController be obtained within a fragment or activity?

<code>Navigation.findNavController(this, R.id.nav_host_fragment)</code> (B) Signup and view all the answers

Consider the following code snippet from a navigation graph:

<action
 android:id="@+id/action_profile_to_friendslist"
 app:destination="@id/friendslist" />

What does this code achieve?

It creates a navigation action that allows navigating from the profile to the friends list fragment. (D) Signup and view all the answers

What is the purpose of `AppBarConfiguration` in Android navigation?

To manage the behavior of the Navigation button in the app bar. (D) Signup and view all the answers

When does the Navigation button in the upper-left corner of the app display a drawer icon instead of an Up button?

When the user is at a top-level destination and the destination uses a DrawerLayout. (A) Signup and view all the answers

Consider the following code:

Bundle args = new Bundle();
args.putString("key", "value");
NavHostFragment.findNavController(FirstFragment.this)
 .navigate(R.id.action_FirstFragment_to_SecondFragment, args);

What is the purpose of this code?

To navigate from <code>FirstFragment</code> to <code>SecondFragment</code> and pass data between them. (D) Signup and view all the answers

In the context of navigating between fragments with data, what method is used in the destination fragment to retrieve the passed data?

<code>getArguments()</code> (B) Signup and view all the answers

If you want to configure the Navigation button in the app bar using only the start destination as the top-level destination, which of the following code snippets is appropriate?

<code>AppBarConfiguration appBarConfiguration = new AppBarConfiguration.Builder(navController.getGraph()).build();</code> (C) Signup and view all the answers

Flashcards

Fragment

A reusable section of an app's UI, managing its own layout, lifecycle, and input events.

Fragment Modularity

Breaking down your activity's UI into smaller pieces, allowing for modifications at runtime.

App Navigation

Refers to the interactions that allow users to move through the different areas and content in your application.

Navigation Host

A UI element that hosts the current navigation destination, swapping destinations in and out during navigation.