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What is Broadcast Receivers?
Broadcast receivers listen for system-wide events or broadcasts. They allow your app to respond to system events such as incoming calls, low battery warnings, or network connectivity changes. Broadcast receivers are useful for triggering actions or starting services based on system events.
What is Content Providers?
Content providers manage a shared set of app data that can be accessed by other apps. They provide a standardized interface for accessing and manipulating data stored in a database or file system. Content providers are useful for sharing data between different parts of your app or allowing other apps to access your app’s data.
Purpose
Content Providers manage access to a shared set of app data, typically stored in a SQLite database or a file system. They provide a standardized interface for other apps to query, insert, update, and delete data.
Functionality
Content Providers allow apps to share and access data in a controlled and secure manner. They define a set of CRUD (Create, Read, Update, Delete) operations that other apps can use to interact with the data.
Use Cases
Content Providers are commonly used when you need to share structured data, such as contacts, calendar events, or media files, between different apps or components within the same app.
What is the difference between Activities and Fragments?
Activities
Purpose: Activities represent a single screen with a user interface (UI) that users can interact with.
Functionality: Activities are the building blocks of the user interface in an Android app. They handle user interactions, such as tapping buttons or entering text.
Lifecycle: Activities have their own lifecycle, including states like onCreate(), onStart(), onResume(), onPause(), onStop(), and onDestroy().
Independence: Each activity runs in its own window, allowing users to navigate between different screens by starting or finishing activities.
Fragments
Purpose: Fragments are reusable UI components that represent a portion of a user interface within an activity.
Functionality: Fragments are like “sub-activities” that can be combined and reconfigured to create dynamic UIs. They can be added, removed, or replaced within an activity dynamically at runtime.
Lifecycle: Fragments have their own lifecycle, similar to activities, including methods like onCreateView(), onStart(), onResume(), onPause(), onStop(), and onDestroyView().
Flexibility: Fragments offer greater flexibility in designing UIs, allowing for modularization and reuse of UI components across different activities.
What are the different ways to handle background tasks in Android?
AsyncTask
AsyncTask is a simple way to perform background tasks on a separate thread while still allowing updates on the UI thread. It’s suitable for short-lived tasks that don’t require complex management.
Thread and Handler
You can create and manage your own threads using the Thread class. To communicate with the UI thread, you can use a Handler to post updates or messages back to the main thread.
IntentService
IntentService is a subclass of Service that handles asynchronous requests (intents) on a worker thread. It’s ideal for long-running tasks that need to be performed in the background, such as downloading files or processing data.
ThreadPoolExecutor
ThreadPoolExecutor allows you to manage a pool of threads to execute multiple background tasks concurrently. It provides more control over thread management and can be customized based on your app’s requirements.
JobScheduler
JobScheduler is a system service introduced in Android 5.0 (API level 21) for scheduling background tasks. It allows you to define conditions and constraints for when a task should run, such as when the device is idle or connected to a Wi-Fi network.
WorkManager
WorkManager is a Jetpack library that provides a flexible and efficient way to schedule background tasks that need to run reliably, even if the app is killed or the device is rebooted. It handles various scenarios, such as network connectivity changes and battery optimization.