20+ Kantar Operations Interview Questions and Answers

An Android photo viewing app with a list of images from disk, one taking half the screen.

• Use RecyclerView to display the list of images

• Use a custom adapter to bind the images to the RecyclerView

• Use a GridLayoutManager with span count of 2 to achieve the half-screen effect

• Load images from disk using a library like Glide or Picasso

• Implement click listeners to handle item selection and display the selected image

Design a screen to show 10 nearest restaurants in a list with uninterrupted scrolling.

• Use a RecyclerView to display the list of restaurants

• Implement a custom adapter to populate the data in the list

• Use a location service to get the user's current location

• Sort the restaurants based on their distance from the user's location

• Load more restaurants as the user scrolls to the end of the list

To search for contacts with duplicate names or numbers, iterate through the list and compare each contact's name and number with the search term.

• Iterate through the list of contacts

• Compare the search term with each contact's name and number

• Return the contacts that match the search term

To transfer the Ball object from one thread to another, we can use Handler or AsyncTask.

• Use Handler to post a Runnable to the main thread's message queue

• Use AsyncTask to perform background operations and update the UI on the main thread

• Pass the Ball object as a parameter or use a shared variable between threads

To create my own HashMap, I would use an array of linked lists to handle collisions and implement key-value pairs using a hash function.

• Create an array of linked lists to store the key-value pairs

• Implement a hash function to generate an index for each key

• Handle collisions by adding elements to the linked list at the corresponding index

• Support operations like put(key, value), get(key), and remove(key)

Given an array of natural numbers in random order, find the first missing natural number.

• Sort the array in ascending order

• Iterate through the sorted array and compare each element with its index

• If the element is not equal to its index + 1, return the missing number

• If all elements are in order, return the next natural number after the last element

Looper/handlers allow passing objects between threads in Android.

• Looper is a message loop that runs in a thread and processes messages from a message queue.

• Handlers are used to send messages to the message queue of a looper.

• When an object is passed from one thread to another using a handler, it is encapsulated in a message and added to the receiving thread's message queue.

• The receiving thread's looper then processes the message and delivers it to the handler's callback method...read more

A weather app that displays images for different weather conditions, taking care of half downloaded images and minimizing data consumption.

• Implement image caching to store downloaded images locally

• Check if the image is already downloaded before making a network request

• Use a progress bar to indicate the download status of the image

• Handle cases where the download is interrupted or incomplete

• Implement a mechanism to resume the download from where it left off

• Optimize image loadin...read more

Android components like Recycler View, View Model, ANR are essential for building robust Android applications.

• Recycler View: Efficient way to display large data sets by recycling views as they scroll off the screen.

• View Model: Manages UI-related data in a lifecycle-conscious way, surviving configuration changes.

• ANR (Application Not Responding): Dialog shown to the user when the main thread of an app is blocked for too long.

• Understanding how these components work internally is...read more

ImageDownloader efficiently handles parallel API calls.

• Use a thread pool to manage parallel API calls.

• Implement caching to avoid redundant API calls.

• Use a priority queue to prioritize image downloads.

• Optimize network requests by using HTTP/2 or multiplexing.

• Consider using a library like Picasso or Glide for image loading and caching.

Deep linking in Android allows users to navigate directly to specific content within an app.

• Deep linking is achieved by defining intent filters in the app's manifest file.

• The intent filter specifies the URL scheme and host that the app can handle.

• When a deep link is clicked, Android checks if any app can handle the URL and prompts the user to choose.

• The chosen app receives the deep link data in the intent's data field.

• Deep linking can be used to open specific screens, perform...read more

Launch mode determines how an activity is launched and how it behaves in the task stack.

• Standard: Creates a new instance of the activity on each launch.

• SingleTop: Reuses the existing instance if it's already at the top of the stack.

• SingleTask: Creates a new task and places the activity at the root of the task.

• SingleInstance: Creates a new task and places the activity as the only one in the task.

IPC (Inter-Process Communication) methods in Android allow communication between different processes.

• Binder: Android's native IPC mechanism, used for communication between processes.

• Intents: Used for communication between components within the same application or between different applications.

• Content Providers: Allow sharing data between applications using a common interface.

• Broadcasts: Used for asynchronous communication between components within an application or between d...read more