Best Android Interview Questions And Answers

Android is an open-source Linux-based operating system commonly used on mobile devices such as smartphones and tablets. It is a kernel-based system that gives developers the ability to develop and deploy simple and/or advanced applications.

The current Android version is 11.0, released in 2020.

SQLite, a standalone open-source serverless database, is built into Android by default.

The android architecture consists of:

• Android Framework
• Android Apps
• Linux kernel
• Libraries

While you CAN change that, the real question must be, "SHOULD you"? Changing the name of an application may impair some of its functionality.

Development tools:

• JDK
• SDK tools
• Eclipse Plugin + ADT

The four main benefits of Android are:

• Open source, so it's free.
• It is platform-independent. Therefore it supports Linux, Windows, and Mac.
• It supports a number of various technologies such as Bluetooth, speech, cameras, Wi-Fi, etc.
• It uses DVM (Dalvik Virtual Machine), a highly optimized virtual machine.

It is a set of tools that Android developers use to develop or write applications. It has a graphical user interface that mimics a portable Android environment, making it easier for devs to create, test, and debug their code.

Tools include:

• Dalvik Debug Monitor Services
• Android emulator
• Android Asset Wrapping Tool
• Android Debug Bridge

Because emulators function like real handheld devices, developers have a nice dedicated sandbox to create safely, edit, test, and debug new applications to see how they work on a real device without risking the real device.

Android mainly uses Java and Kotlin but also supports C / C ++, which will run faster when used with the Android SDK.

It is a set of APIs that allows developers to build applications and consists of:

• Intention
• Activities
• Content providers
• Others

Be that as it may, it is the intent to perform an action, a message that is passed between components. Intents request actions from another component, such as sending an email, opening a web page, or launching a given action. There are two types:

• Implicit intent
  
  Here, the intent does not define the target component, requiring the Android system to evaluate the components.

• Explicit intent
  
  Explicit intent, on the other hand, directly identifies the target component.

This is a broadcast using the send sticky broadcast () method. The intent remains after the broadcast, allowing others to collect data from it.

These are the parts of the mobile application that the user sees and interacts with. It is a graphical user interface (GUI) representing a single Android screen.

Four states:

• Active: The action is at the top of the stack, running in the foreground.
• Suspended: The activity is still displayed but cannot receive user input events. it's in the background
• Stopped: The action is invisible and therefore paused and hidden or hidden by another action.
• Destroyed: The action process has been terminated, completed, or terminated.

Content providers exchange information between different Android applications. They allow users to access data in the application. Examples include contact information, images, video, and audio.

In this case, a toast is a pop-up window (hence the word) giving feedback on a user-initiated operation, informing the user about the current status of said operation. For example, when a smartphone user sends a message to a friend, a toast is displayed with the words “send a message.”

Mobile testing is performed on the mobile device itself, in particular in device functions such as Contacts, SMS, browsers, and the calling function. Mobile application testing samples the capabilities and functionality of applications downloaded to a mobile device.

Packages are used to transfer the required data to subfolders.

Use the findViewById keyword.

The weaknesses of Android stem from one of its strengths, namely that it is available everywhere and can run on a wide variety of devices.

• First of all, developers can find it difficult to create apps that easily adjust the display to fit the different screen sizes of all these different devices.
• Second, the large number of devices has led to the emergence of a large number of individual versions of Android that suit them, so there is no single set of policies governing updates or settings to work on many operating systems. There is anarchy!

No, it can’t.

It is an abbreviation for Android Asset Packaging Tool. This tool gives developers the ability to work with zip-compatible archives, including viewing, creating, and extracting content.

This acronym stands for Android Debug Bridge (a tool included with the SDK). It is a command-line tool used to exchange data between emulator instances.

It is short for Android Packaging Kit. Each file in the Android packaging key is compressed into one file - the APK.

It is an acronym for Application Not Responding, a pop-up or notification that is triggered when an application experiences a delay for the user due to too many functions running concurrently.

They are placed as XML files in the layout folder.

Exceptions include:

Inflate the exception

• Surface.OutOfResourceException
• SurfaceHolder.BadSurfaceTypeException
• WindowManager.BadTokenException

Six main elements:

• AndroidManifest.xml
• build.xml
• bin /
• src /
• res /
• resources/

Four dialog boxes:

• Alert Dialog: Contains selectable items such as radio buttons and/or checkboxes.
• Progress Dialogue: Shows progress, either through a progress wheel or on a lane.
• Date picker dialog: allows the user to select a date
• Timing Dialogue: it allows the user to select a time

When an application crashes frequently, these are the best ways to fix it:

• This could be a memory issue. Make sure there is enough space in memory.
• Clear app data by clearing cache memory using "settings" in the app manager.
• Not all applications work the same on different machines, so you might have to tinker with memory management.
• This could be a compatibility issue; A problem that can be solved by pre-testing the application on as many devices as possible.