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iOS Developer EssentialsView Controller & App Lifecycle

20 items

1

App States and Background Transitions

Quiz
2

State Restoration and Cold Starts

Quiz
3

Background Task Ends Too Early

Code Quiz
4

State Restoration Key Mismatch Bug

Code Quiz
5

useEffect Cleanup in Mobile Apps

Slides / Video
6

useEffect Cleanup on Mobile

Flashcard
7

Process Death and State Restoration

Slides / Video
8

Cold vs Warm Start & State Restoration

Flashcard
9

App State Transitions

Flashcard
10

useFocusEffect Re-run Bug

Code Quiz
11

View Controller Focus & Cleanup

Quiz
12

App State Transitions Explained

Slides / Video
13

Component Lifecycle & Screen Focus

Slides / Video
14

UIViewController Lifecycle & Focus

Flashcard
15

Saving State on Background

Code Quiz
16

AppState Listener Cleanup Bug

Code Quiz
17

iOS App States Basics

Quiz
18

AppState & Component Lifecycle in RN

Quiz
19

AppState & Component Lifecycle in RN

Slides / Video
20

AppState & Component Lifecycle in RN

Flashcard
FlashcardIntermediate

useEffect Cleanup on Mobile

How useEffect's cleanup function prevents leaks when components unmount on mobile.

Question

In a React (Native) component, when does useEffect's cleanup function run, and why does it matter on mobile?

Click to reveal answer