Passing parameters between screens in React Native - UI Render Trace

Component - Passing parameters between screens

This UI component demonstrates how to pass data (parameters) from one screen to another in a React Native app using navigation. It shows a simple flow where a button on the first screen sends a message to the second screen, which then displays it.

Widget Tree

HomeScreen, DetailsScreen

↓

Text, Button

The app uses a navigation container with a stack navigator managing two screens: HomeScreen and DetailsScreen. HomeScreen contains a View with a Text label and a Button. DetailsScreen contains a View with a Text that shows the passed parameter.

Render Trace - 4 Steps

Step 1: NavigationContainer

Step 2: HomeScreen > View

Step 3: HomeScreen > Button

Step 4: DetailsScreen > View

State Change - Re-render

Trigger:User taps the 'Go to Details' button on HomeScreen

Before

Current screen is HomeScreen, no parameters passed

→

After

Current screen changes to DetailsScreen with parameter { message: 'Hello from Home!' }

Re-renders:DetailsScreen and its children re-render to show the passed message

UI Quiz - 3 Questions

What happens when the button on HomeScreen is pressed?

A The app navigates to DetailsScreen and passes a message parameter

B The app reloads HomeScreen without changes

C The app closes

D The button text changes

Key Insight

Passing parameters between screens is a common way to share data in mobile apps. Using navigation libraries, you can send simple data like strings or objects when moving from one screen to another. The receiving screen can then use this data to update its UI, making the app interactive and dynamic.