0
176
ViewsReact Native: Highlight component / area by darkening the rest
Is there any React Native library that renders a dark transparent overlay over the screen and highlights a component with a shape?
While building a set of overlays for how-to use an app (tutorials), I got stuck at a point where I need to implement a vignette component to highlight a specific area.
Ideally I am looking for a library that provides a solution like React Native Walkthrough Tooltip that knows the position of the highlight based on the component. Sadly, this one limits me to using only the message box shape.
I already tried 2 different solutions: one based on React Native MaskedView and another based on react-native-hole-view. For both I am using React Native measure to get the position of the component that needs highlighting but I am not happy with the result so far.
Is there any alternative out there?
Important note: as I am using react navigation, on some screens I need to cover the header and bottom navigation, this forces me to render my HighlightHoleOverlay within a transparent react native modal.
1 answers
Answer question0
I've authored a library that I think would fit your needs, you can find it here: react-native-highlight-overlay.
This library allows you to draw an overlay over the entire screen (or only a specific component) and highlight a single element below the highlight. It's 100% automatic, no manual size calculations required, all you need to do is wrap the component(s) you want to highlight with HighlightableElement and give it a unique ID that you then supply to the overlay. Basic example:
import {
HighlightableElement,
HighlightableElementProvider,
HighlightOverlay,
} from "react-native-highlight-overlay";
// Remember to wrap the ROOT of your app in HighlightableElementProvider!
return (
<HighlightableElementProvider>
<HighlightableElement id="important_item">
<TheRestOfTheOwl />
</HighlightableElement>
{/*
* The HighlightOverlay should be next to the ROOT of the app,
* since it is NOT a modal, it's just an absolutely positioned view.
* If you want it to be a modal, wrap it in <Modal> yourself first,
* but I recommend not using modals since they can be buggy.
*/}
<HighlightOverlay
// You would usually use a state variable for this :)
// Or store it in a context / store so you can change it from anywhere in the app.
highlightedElementId="important_item"
onDismiss={() => {
// Called when the user clicks outside of the highlighted element.
// Set "highlightedElementId" to nullish to hide the overlay.
}}
/>
</HighlightableElementProvider>
);
If you make the highlight circular and give it some padding, say padding: 25, it should look just like your image.