9 Common Interview Questions About Android (With Example Answers)
Android developers are in high demand and make an average of $118,389 per year. If you want to become an Android application developer, knowing how to answer some of the most common interview questions can help you feel more confident at your interview. This article shows you how to answer some of the most common Android interview questions.
Questions and answers about Android for an interview
Here are some common questions and answers about Android:
- What does it mean by Android?
- What do they look like?
- When should a fragment be used instead of an action?
- How do you know that the user can use the back button to go back to the last Fragment when you replace one with another?
- What are some of the more advanced features of Android, and how can you use them?
- What are some mistakes you could make?
- What are views and how do you use them?
- Do you know how to create a bound service?
- What is the difference between an intention that is clear and one that isn’t?
1.What exactly is an Android?
One of the first questions the interviewer will probably ask you is how much you know about Android. You might need to know what Android is, how developers use it, and why you’d want to use it. Think about giving specific examples of when and how you’ve used the platform and why.
“Android is a free platform that is open source and runs on Linux. Any developer who wants to use this mobile OS can get a free Software Development Kit. This is good for developers and businesses because it makes licensing and development less expensive. I’ve used it to make apps with a variety of helpful tools for my own personal development projects.”
2.What do you mean by fragments?
If you make Android apps, you may use fragments a lot. If you know what the words mean and when to use them, you can give a better answer at your interview. You can show that you know them by talking about some of their features and how you’ve used them in your own work.
“A piece of the user interface is called a fragment. You can use more than one fragment in a single task. While an activity is running, you can add or remove fragments. A fragment has its own life cycle, but it is always a part of an activity. I sometimes use fragments to set up the User Interface of an app’s content and functions so they are easy to find and use.
3.When should a fragment be used instead of an action?
You need to know when to use an activity and when to use a fragment as a developer. A good answer would list different ways each one could be used.
“Making an activity’s code is more complicated than making a fragment’s code. Before you can start the new one, you have to pause, stop, or get rid of the old one. Use an activity only when you want to change the whole screen. Other than that, you should use fragments all the time. Developers often use fragments when a navigation method is being used or when the user would benefit from having two layouts next to each other.
4. When you replace one fragment with another, how do you know that the user can use the back button to go back to the previous fragment?
As a developer, you need to know how fragments work and how they change over time. Since this function might be used every day, you might have to explain that you know it and what a back stack is.
Example: “Save each fragment transaction on the back stack so that the user can use the back button to get to the last fragment. You can do this before you finish that transaction by calling “addToBackStack().”
5.What are some of the more advanced features of Android and how do they help?
Android is liked by developers because it has a lot of cool features. You can list a few of these things along with the things you like about Android. In your answer, you can talk about specific applications and explain why they are useful.
“Using Android has a lot of good points. ThreadPool is a place where many copies of the same task are run at the same time by a group of worker threads and a task queue. When this ability is used right, it makes an app work better. Using ThreadPool is also more efficient than having multiple tasks wait for a single thread to run. This also keeps you from having to build and then destroy a thread every time you need a worker thread, which can take a long time.
6. What are some mistakes you could make?
As a developer, you’ll run into errors often. Even the most experienced developers run into problems, but what makes a developer effective and productive is knowing how to deal with these problems. You can point out a specific mistake and explain how to fix it.
Example: “A common Android error is “Application Not Responding.” When I see this in my work, I know not to use the main thread for tasks that take a long time or are hard. When something blocks the main thread for more than five seconds and stops the UI from responding, this error happens. Taking most of the work off the main thread is the best way to fix this.”
7.How do you use views, and what are they?
Views are a big part of making Android apps. You can tell people what they are, how they are made, and the best way to use them.
“A view is a part of the Android User Interface that reacts to what the user does.” You should subclass the view that is closest to the custom component you want to make when making a view. Once you have extended the class, you can make a res/values/attrs.xml file with a list of the attributes you want to use with the custom view.
By putting the app on an Android device, you can check for too much overdraw and make better use of the view. The next step is to turn on “Debug GPU Overview.” You can also make the view hierarchy flat. You can do this by looking at the view hierarchy with the “Hierarchy Viewer” tool in Android Studio.
8. Do you know how to make a bound service?
Developers often use bound service in Android apps. You can talk about how you would build one and make a list of the steps you would take. You can also explain the process by showing how you’ve built a bound service in the past.
Example: “The first step in making a bound service with Android Interface Definition Language is to define the AIDL interface for a.aidl file. Then, you save the file in the src/ directory of the application that hosts the activity and any other applications needed to bind the service. Then, you can build the app and use the tools in the Android SDK to create the IBinder interface file, which goes in the gen directory.
9.What is the difference between a goal that is clear and one that isn’t?
In an Android app, you can use different intents depending on what kind of function you are making. You can explain the difference between implicit and explicit intent and when to use each.
Example: “An explicit intent tells the system which part of the system or activity to use to fulfill the intent. “Implicit intent” is what happens when you say what you want to do. The Android system then checks to see which registered parts can control that action. Most of the time, you will start application components with a clear goal in mind. When you want to talk to other parts of an application that is not your own, you would use implicit intents.
