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package br.com.nglauber.jetpackcomposeplayground.screens
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.*
import androidx.compose.foundation.lazy.LazyColumn
import androidx.compose.foundation.lazy.LazyRow
import androidx.compose.foundation.lazy.items
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.material.MaterialTheme
import androidx.compose.material.Text

Android Interview Questions

Q1: Explain activity lifecycle ☆☆

Answer: As a user navigates through, out of, and back to your app, the Activity instances in your app transition through different states in their lifecycle.

To navigate transitions between stages of the activity lifecycle, the Activity class provides a core set of six callbacks: onCreate(), onStart(), onResume(), onPause(), onStop(), and onDestroy(). The system invokes each of these callbacks as an activity enters a new state.

Interview Questions

Kotlin

Q1: What is a primary constructor in Kotlin? ☆☆

Answer: The primary constructor is part of the class header. Unlike Java, you don't need to declare a constructor in the body of the class. Here's an example:

@JoseAlcerreca
JoseAlcerreca / EventObserver.kt
Created April 26, 2018 12:14
An Observer for Events, simplifying the pattern of checking if the Event's content has already been handled.
/**
* An [Observer] for [Event]s, simplifying the pattern of checking if the [Event]'s content has
* already been handled.
*
* [onEventUnhandledContent] is *only* called if the [Event]'s contents has not been handled.
*/
class EventObserver<T>(private val onEventUnhandledContent: (T) -> Unit) : Observer<Event<T>> {
override fun onChanged(event: Event<T>?) {
event?.getContentIfNotHandled()?.let { value ->
onEventUnhandledContent(value)
@JoseAlcerreca
JoseAlcerreca / Event.kt
Created April 26, 2018 10:25
An event wrapper for data that is exposed via a LiveData that represents an event.
/**
* Used as a wrapper for data that is exposed via a LiveData that represents an event.
*/
open class Event<out T>(private val content: T) {
var hasBeenHandled = false
private set // Allow external read but not write
/**
* Returns the content and prevents its use again.
@lopspower
lopspower / README.md
Last active May 16, 2025 20:12
Hexadecimal color code for transparency

Hexadecimal color code for transparency

Twitter

How to set transparency with hex value ?

For example, you want to set 40% alpha transparence to #000000 (black color), you need to add 66 like this #66000000.

Download This sample on Google Play Store