Free AND-801 Practice Test Questions and Answers (2026)

The presence of LocationManager and LocationListener variables indicates that the application is designed to interact with the device's location services. LocationManager is the primary Android system service class used to request and obtain the device's geographical location. The LocationListener interface is implemented to receive callbacks from the LocationManager when the location changes. Therefore, this code is fundamental for an application that needs to capture a user's real-time coordinates (latitude and longitude) and use that data within its operational workflow, such as showing the user's current position on a Google Map.

A. This app is just to show locations on Google map. This is incorrect because the code implies the app actively retrieves the user's current location, which is more than just displaying a static map or predefined locations.
B. LocationListener is used to give the app user to change the Google map database. This is incorrect. LocationListener is a callback interface for receiving location updates from the system; it has no capability to modify any external map databases.
D. These classes are not related to Google map. This is incorrect. While LocationManager and LocationListener are part of the core Android framework, they are fundamentally related to and commonly used with map functionalities to create location-aware applications.

1. Official Android Developer Documentation. The documentation for LocationManager states, "This class provides access to the system location services. These services allow applications to obtain periodic updates of the device's geographical location." The LocationListener is described as, "Used for receiving notifications from the LocationManager when the location has changed." This confirms their role in capturing user location.

Source: Android Developers, LocationManager Class Reference, android.location package.

Source: Android Developers, LocationListener Interface Reference, android.location package.

2. University of Washington, CSE 481I - Sound, Sensors, and Location. Course materials explain that to get a user's location, an app must get an instance of the LocationManager and register a LocationListener to receive updates. This process is explicitly for capturing coordinates to be used by the application.

Source: University of Washington, Paul G. Allen School of Computer Science & Engineering, CSE 481I, Lecture 10: Location & Maps, "Getting Location" section.

3. Vanderbilt University, CS 282: Mobile Application Development. Lecture slides on "Location-Aware Apps" detail the use of LocationManager and LocationListener as the mechanism to "find the location of the device" by requesting updates, which provides the application with Location objects containing latitude and longitude.

Source: Vanderbilt University, Department of Electrical Engineering and Computer Science, CS 282, "Location-Aware Apps" lecture notes, Slides 10-15.

The statement is factually correct. The Android platform is an open-source software stack, with its source code released under the Android Open Source Project (AOSP). This stack is built upon a modified version of the Linux kernel. The kernel serves as the hardware abstraction layer, managing core system services such as process management, memory management, security, and networking. The open-source nature allows manufacturers to freely adapt the OS for their hardware, while its Linux foundation provides a stable and proven core for the operating system.

B. False: This is incorrect because the two central claims in the statement—that Android is open source and Linux-based—are defining characteristics of the platform, as confirmed by official Android documentation and academic sources.

1. Official Vendor Documentation: Google. (n.d.). What is Android? Android Open Source Project. Retrieved from source.android.com. In the "Introduction" section, the first sentence states, "Android is an open source, Linux-based software stack created for a wide array of devices and form factors." The "Android Platform Architecture" section further details the Linux Kernel as the foundation of the stack.

2. University Courseware: Parlante, N. (2015). Stanford CS 193A, Android App Development, Winter 2015. Stanford University. In Lecture 1, "Intro, Java Review," Slide 10 ("Android Stack") explicitly shows the Linux Kernel at the base of the Android architecture and describes the overall system as open source.

3. Peer-reviewed Academic Publication: Wei, L., & Jie, X. (2011). Research on the Android System Architecture and Its Application. Proceedings of the 2011 International Conference on Computer Science and Service System (CSSS). Page 1, Section II.A, states, "Android is a free, open source mobile operating system based on Linux 2.6 kernel." DOI: https://doi.org/10.1109/CSSS.2011.5972039

In Android XML layouts, attributes defined by the core Android framework are prefixed with the android: namespace. The textColor attribute is the standard property used to set the color of the text for UI elements like TextView. When a color is defined in the /res/values/colors.xml file, it can be referenced as the value for this attribute using the syntax @color/colorname. This practice promotes reusability and simplifies theme management across the application's layouts. The other options use incorrect namespaces or attribute names that are not recognized by the Android UI toolkit.

A. Java:textcolor Java: is not a valid XML namespace for Android layout attributes; it refers to the programming language, not a UI schema.
B. color:textformat color: is not a standard Android namespace, and textformat is not the correct attribute name for setting the text's color.
D. kotlin:textcolor kotlin: is not a valid XML namespace for Android layout attributes; it refers to the programming language, not a UI schema. ---

1. Official Android Developer Documentation, "TextView": The official documentation for the TextView class lists android:textColor as the XML attribute for setting the text color.

Source: Google, Android Developers.

Reference: TextView class reference, XML Attributes table, row for android:textColor. Available at: https://developer.android.com/reference/android/widget/TextView#attrandroid:textColor

2. Official Android Developer Documentation, "Color resources": This guide explains how to define colors in colors.xml and explicitly shows an example of applying a color resource to the android:textColor attribute in an XML layout.

Source: Google, Android Developers.

Reference: "Accessing color resources" section, XML example. Available at: https://developer.android.com/guide/topics/resources/color-list-resource#accessing

3. Stanford University, CS 193A Courseware, "Views, Layouts, and UI": Lecture slides demonstrate the use of XML attributes for UI widgets, showing android:textColor as the correct attribute for a TextView.

Source: Stanford University, CS 193A - Android App Development, Winter 2017.

Reference: Lecture 03 Slides, "Views, Layouts, and UI", Slide 21, TextView XML example. Available at: https://web.stanford.edu/class/cs193a/lectures/03-Views-Layouts-UI.pdf

The CheckBox is a standard UI widget provided by the Android framework. Android Studio's Layout Editor features a "Palette" panel which contains a list of UI components that can be used to build a layout visually. The CheckBox widget is available in this Palette, typically located under the "Buttons" category. Developers can simply drag the CheckBox from the Palette and drop it onto the design canvas. This core functionality was present in Android Studio 3.0 and has been maintained in all subsequent versions.

A. False: This is incorrect because the CheckBox is a fundamental UI component and is a standard, draggable item within the Layout Editor's Palette in Android Studio 3.0 and all later versions.

1. Android Developers Official Documentation. "Build a UI with Layout Editor". In the section titled "Introduction to the Layout Editor," the documentation describes the "Palette" as a panel that "provides a list of widgets and layouts that you can drag into your layout in the editor." Screenshots and descriptions on this page consistently show common widgets like CheckBox available in the Palette.

2. Android Developers Official Documentation. "Checkboxes | Material Design 3". This guide details the usage and importance of checkboxes in Android UI, establishing it as a core, officially sanctioned component intended for widespread use by developers through tools like Android Studio.

3. Vanderbilt University, Department of Computer Science. "CS 251: Intermediate Software Design, Lecture 20 - Android GUI Components I". Course materials frequently illustrate the Android Studio Layout Editor, showing the Palette panel populated with standard widgets, including CheckBox, which can be dragged onto the layout. (See slides on basic UI widgets).

The provided Kotlin code correctly sets up an event listener for a button click. The buttonsum.setOnClickListener block contains the logic that will execute when the user clicks the button. Inside this block, the code retrieves the text from the N1 and N2 EditText widgets, converts these text values to integers using .toInt(), calculates their sum, and then displays the result by setting the text property of the resultview TextView. This entire process is triggered by the button click event.

A. The code updates the UI directly using resultview.text = sum.toString(). A "print out method" like Log.d is for debugging, not for displaying results to the user.
C. This statement is false. The code explicitly converts the text from N1 and N2 to integers on the lines val num1 = N1.text.toString().toInt() and val num2 = N2.text.toString().toInt().
D. The EditText widgets (N1 and N2) are the standard Android components for user input. The Android OS automatically provides the input method (keyboard) when an EditText is focused. ---

1. Official Android Developer Documentation, "Buttons": The official documentation explains how to handle user interactions with buttons. It specifies that a click listener can be declared programmatically using setOnClickListener { } to define the action performed upon a click. This validates the event-handling mechanism used in the code.

Source: Google, Android Developers. "Buttons | Android Developers".

Section: "Respond to click events," Programmatic declaration example.

2. Official Android Developer Documentation, "Input controls": This guide details how to use EditText for user input. It confirms that the text property (or getText() method) is used to retrieve the content entered by the user, which must then be converted to the appropriate data type for processing.

Source: Google, Android Developers. "Input controls | Android Developers".

Section: "Text fields," Retrieving the value.

3. Kotlin Language Official Documentation, "Basic Types": The official Kotlin documentation specifies that a String can be converted to an Int using the toInt() function. This confirms the validity of the data type conversion used in the code snippet before the summation.

Source: JetBrains, kotlinlang.org. "Basic Types".

Section: "Explicit conversions," Example: val y: Int = x.toInt().

4. Stanford University, CS193A - Android App Development, Lecture 2: University courseware on Android development covers these fundamental concepts. This lecture explains the roles of View objects like Button, EditText, and TextView, and demonstrates using setOnClickListener to connect UI events to application logic, such as reading from an EditText and writing to a TextView.

Source: Stanford University, CS193A Course Materials.

Reference: Lecture 2, "Android Basics, Views, Layouts," Slides covering Event Listeners and UI Widgets.

The provided XML code defines a UI element. The key attribute android:name="com.google.android.gms.maps.SupportMapFragment" explicitly specifies the class for this fragment. SupportMapFragment is a component from the Google Play Services library designed to embed an interactive Google Map within an Android application's layout. The android:id="@+id/map" attribute assigns a unique identifier to this fragment, allowing the hosting Activity or Fragment to obtain a handle to it and interact with the map programmatically.

A. A RecyclerView is a distinct UI component for displaying large sets of data efficiently and would be defined with a tag.
B. Application permissions are declared within the AndroidManifest.xml file, not in a UI layout file like activitymain.xml.
D. This layout code defines a visual component. It is unrelated to granting permissions or managing connections to a SQLite database.

1. Google. (n.d.). Add a map to an Android app. Maps SDK for Android | Google for Developers. In the "Add a map" section, the official documentation provides the exact XML code structure for adding a map, stating: "Add a element to your activity's layout file... In the element, set the android:name attribute to com.google.android.gms.maps.SupportMapFragment."

2. Google. (n.d.). SupportMapFragment. Google Play services | Google for Developers. The official class documentation describes SupportMapFragment as "A Map component in an app. This fragment is the simplest way to place a map in an application."

3. Purdue University. (n.d.). ECE 49595: Mobile Computing - Lecture 11: Location and Maps. College of Engineering. Course materials on integrating Google Maps into Android applications demonstrate adding a SupportMapFragment to the layout XML as the primary method for displaying a map. The lecture notes specify using the tag with android:name="com.google.android.gms.maps.SupportMapFragment".

The android:icon and android:roundIcon attributes within the tag of the AndroidManifest.xml file are used to define the application's launcher icons. The android:icon attribute specifies the primary, default icon that represents the app on a device's home screen, in the app drawer, and in the Google Play Store. The android:roundIcon attribute, introduced in API level 25, provides a circular icon variant for launchers and devices that support this format, ensuring a consistent and adaptive visual presentation across the diverse Android ecosystem.

B. These attributes define the icon for the installed application on a device, not for the Android Studio development environment's user interface.
C. The icon is displayed on all Android devices, including physical hardware and emulators, not exclusively on the emulator.
D. The AndroidManifest.xml file is specific to the Android operating system and has no effect on applications installed on iOS (iPhone) devices. ---

1. Official Android Developer Documentation, element: The documentation explicitly defines the purpose of these attributes.

For android:icon: "An icon for the application as a whole... This icon is used to represent the application in contexts like the home screen, the launcher, and the list of recent apps."

For android:roundIcon: "A round icon for the application... used in contexts that require a circular icon, such as the launcher on devices running Android 7.1 (API level 25) or higher."

Source: Google LLC. (n.d.). App manifest overview | element. Android Developers. Retrieved from https://developer.android.com/guide/topics/manifest/application-element#icon

2. Official Android Developer Documentation, App Icons: This guide details the usage and importance of providing different icon assets, including their role in the Google Play Store.

"Your app's launcher icon is the first thing people see on the Google Play store and on their devices after installation."

Source: Google LLC. (n.d.). App icons. Android Developers. Retrieved from https://developer.android.com/distribute/google-play/resources/icon-design-specifications

3. University of Washington, CSE 340 Courseware: University course materials on Android development corroborate the function of the manifest file.

Section: The Android Manifest: "The manifest file describes essential information about your app to the Android build tools, the Android operating system, and Google Play... It must declare... The app icon (android:icon)."

Source: University of Washington. (2023). The Android Manifest. Paul G. Allen School of Computer Science & Engineering. Retrieved from https://courses.cs.washington.edu/courses/cse340/23wi/lectures/03-android-basics/ (Content under "The Android Manifest" section).

Android applications operate within a security sandbox and require explicit permissions to access resources outside of their own data. To load a web page from the internet, a WebView must be able to make network requests. This capability is granted by declaring the INTERNET permission in the application's manifest file (AndroidManifest.xml). Without this declaration, the Android operating system will block all network attempts made by the app, causing the WebView to fail when trying to load the external URL. This is a fundamental security measure in Android development.

A. The activitymain.xml file is used for defining the user interface layout, not for managing network permissions or system connectivity settings.
B. Android's security model mandates that apps explicitly request permissions for sensitive operations; internet access is not granted by default.
C. A WebView is an embedded component that renders web content within the app itself; it does not use or configure external browsers like Firefox.

1. Official Android Developer Documentation, "Build web apps in WebView": Under the section "Add permissions to your manifest," the documentation explicitly states: "To enable your WebView to access the internet and load web pages, add the INTERNET permission to your manifest file. ".

Source: https://developer.android.com/develop/ui/views/layout/webapps/webview#permissions

2. Official Android Developer Documentation, "Permissions on Android": This guide details the Android permission system, explaining that for an app to use certain system features, it must declare a element in the app manifest. It lists android.permission.INTERNET as a permission for network access.

Source: https://developer.android.com/guide/topics/permissions/overview#declare

3. Vogella GmbH, "Android WebView and HTML," Tutorial by Lars Vogel (a resource often referenced in academic contexts for Android development): In Section 2, "Adding the Internet permission," the tutorial states, "To use a WebView which connects to the Internet, you need to add the android.permission.INTERNET permission to your Android manifest file."

Source: https://www.vogella.com/tutorials/AndroidWebView/article.html, Section 2.

The issue lies in the mismatch of keys used for sending and receiving data via the Intent. In MainActivity.kt, the data is placed into the intent using the key "pass" with the intent.putExtra("pass", pass) method. However, in SecondActivity.kt, the code attempts to retrieve the data using a different key, "name", with intent.getStringExtra("name"). For the Intent mechanism to work correctly, the key used to put the extra data must be identical to the key used to get the extra data. The correct solution is to modify SecondActivity.kt to use the same key, "pass", for data retrieval.

A. startActivity(intent) is used to launch a new activity. Calling it within SecondActivity would not fix the data retrieval and would cause incorrect application flow.
B. putExtra is a method for adding data to an Intent, not for retrieving it. The correct method to retrieve a string is getStringExtra.
C. An if statement can be used to check if data exists, but it does not solve the fundamental problem of the mismatched keys causing the data to be null.

1. Official Android Developer Documentation. The guide on starting another activity explicitly demonstrates that the key used in putExtra() must match the key used in getStringExtra() to successfully pass data.

Source: Android Developers, "Start another activity".

Reference: In the section "Add extra data to the intent," the example code uses a constant EXTRAMESSAGE for both the sending activity's putExtra(EXTRAMESSAGE, message) and the receiving activity's intent.getStringExtra(EXTRAMESSAGE). This illustrates the requirement for matching keys. (developer.android.com/training/basics/firstapp/starting-activity)

2. Stanford University, CS 193A - Android App Development, Winter 2017. The course materials on Activities and Intents show the standard practice for passing data.

Source: Lecture 03 Slides - "Activities and Intents".

Reference: Slide 23, titled "Passing data with an Intent," provides a clear example: intent.putExtra("name", value); to send data and intent.getStringExtra("name"); to retrieve it, reinforcing that the key (in this case, "name") must be consistent. (web.stanford.edu/class/cs193a/lectures/03-Activities-Intents.pdf)

The Android operating system is built on a layered architecture where core system components, including the Application Framework and native libraries, are designed as shared resources. This architecture allows multiple applications to access and utilize the same underlying library code for common functionalities such as UI management, connectivity, and data storage. This shared model is fundamental to the platform's efficiency, as it conserves system memory and storage space by preventing redundant code duplication across applications. Each application runs in its own process but links to these common system libraries at runtime.

B. False: This is incorrect. A core design principle of the Android platform is the use of shared libraries. If this were false, each application would need to bundle its own copy of the entire Android framework, which would be extremely inefficient and unmanageable.

1. Official Android Documentation: The "Platform Architecture" guide explicitly details the layered stack. The "Java API Framework" and "Native C/C++ Libraries" layers are presented as foundational components available to all applications. It states, "The Android platform provides a set of Java APIs that are used to develop apps... These APIs rely on the system services and the Android runtime to do the work." This confirms the shared nature of the underlying libraries.

Source: Android Developers, "Platform Architecture," System Libraries section. Retrieved from https://developer.android.com/guide/platform#system-libraries.

2. Academic Publication: In the book Android System Programming, the architecture is described in detail. The author explains, "The Android framework is a set of Java classes, interfaces, and other precompiled code that gives an application access to the host device hardware and system services... The framework is shared by all applications."

Source: Ye, R. (2017). Android System Programming: Porting, customizing, and debugging Android HAL. Packt Publishing. Chapter 1, "Android Architecture," p. 14.

3. University Courseware: Reputable computer science courses on mobile development consistently teach this architectural principle. Lecture materials on the Android stack show the Application Framework and Libraries as a common layer upon which individual applications are built, emphasizing that these are not part of the individual application packages but are provided by the system.

Source: CS 193A, "Android App Development, Lecture 1: Introduction to Android." Stanford University. The lecture slides typically include a diagram of the Android OS stack, illustrating the shared library layers.