/react-native-image-header-scroll-view

ScrollView with an image in header which becomes a navbar

Primary LanguageJavaScriptMIT LicenseMIT

react-native-image-header-scroll-view

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A ScrollView-like component that:

  • Has a fixed image header
  • Keep the image as a nav bar
  • Works on iOS and Android

Installation

$ npm install react-native-image-header-scroll-view --save

Demo

react-native-image-header-scroll-view demo android|react-native-image-header-scroll-view demo ios

You can find this example code here : https://github.com/bamlab/react-native-image-header-scroll-view-example/blob/master/src/Pages/TvShow.js

Basic Usage

import HeaderImageScrollView, { TriggeringView } from 'react-native-image-header-scroll-view';

// Inside of a component's render() method:
render() {
  return (
    <HeaderImageScrollView
      maxHeight={200}
      minHeight={MIN_HEIGHT}
      headerImage={require("../../assets/NZ.jpg")}
      renderForeground={() => (
        <View style={{ height: 150, justifyContent: "center", alignItems: "center" }} >
          <TouchableOpacity onPress={() => console.log("tap!!")}>
            <Text style={{ backgroundColor: "transparent" }}>Tap Me!</Text>
          </TouchableOpacity>
        </View>
      )}
    >
      <View style={{ height: 1000 }}>
        <TriggeringView onHide={() => console.log("text hidden")}>
          <Text>Scroll Me!</Text>
        </TriggeringView>
      </View>
    </HeaderImageScrollView>
  );
}

Result :

Basic Usage

You can find examples in a dedicated repository.

Usage (API)

All of the properties of ScrollView are supported. Please refer to the ScrollView documentation for more detail.

The HeaderImageScrollView handle also the following props. None is required :

Header

Property Type Default  Description Example
renderHeader function  Empty view Function which return the component to use as header. It can return background image for example. example
headerImage Image source Props (object or number)  undefined Shortcut for renderHeader={() => <Image source={this.props.headerImage} style={{ height: this.props.maxHeight, width: Dimensions.get('window').width }} />} example
maxHeight number 80 Max height for the header example
minHeight number 125 Min height for the header (in navbar mode) example
minOverlayOpacity number 0 Opacity of a black overlay on the header before any scroll example
maxOverlayOpacity number 0.3 Opacity of a black overlay on the header when in navbar mode example
overlayColor string black Color of the overlay on the header example
useNativeDriver boolean false Use native driver for the animation for performance improvement. A few props are unsupported at the moment if useNativeDriver=true (onScroll, ScrollComponent, renderTouchableFixedForeground) -
headerContainerStyle Object undefined Optional styles to be passed to the container of the header component
disableHeaderGrow boolean undefined Disable to grow effect on the header

Foreground

Property Type Default  Description Example
renderForeground function Empty view Function which return the component to use at foreground. The component is render in front of the header and scroll with the ScrollView. It can return a title for example. example
renderFixedForeground function Empty view Function which return the component to use as fixed foreground. The component is displayed with the header but not affected by the overlay. example
foregroundExtrapolate string clamp Optional prop that allows override extrapolate mode for foreground. Use null to allow extrapolation, which is usefull for using foreground as bottom title -
foregroundParallaxRatio number 1 Ration for parallax effect of foreground when scrolling. If 2, the header goes up two times faster than the scroll example
fadeOutForeground bool false If set, add a fade out effect on the foreground when scroll up example
renderTouchableFixedForeground function Empty view Same as renderFixedForeground but allow to use touchable in it. Can cause performances issues on Android example
fixedForegroundContainerStyles Object undefined Optional styles to be passed to the container of the fixed foreground component

Mixed

Property Type Default  Description Example
ScrollViewComponent Component  ScrollView The component to be used for scrolling. Can be any component with an onScroll props (ie. ListView, FlatList, SectionList or ScrollView) example
scrollViewBackgroundColor string  white Background color of the scrollView content example

TriggeringView

The module also export a TriggeringView component. It is a spy View you put on the page that will can call various callback during the scroll. It accept callback called when it disappear or appear at the top of the ImageHeaderScrollView. You can see an exemple in the dedicated repository.

All of the properties of View are supported.

Property Type Description
onBeginHidden function  Called when the component start to be hidden at the top of the scroll view.
onHide function  Called when the component is not displayed any more after scroll up
onBeginDisplayed function  Called when the component begin to be displayed again after scroll down
onDisplay function  Called when the component finished to be displayed again.
onTouchTop function  Called when the Top of the component touch the Top of the ScrollView. (onDisplay + onBeginHidden)
onTouchBottom function  Called when the Bottom of the component touch the Top of the ScrollView. (onHide + onBeginDisplayed)

FAQ

How to remove the black image overlay

Just set the maxOverlayOpacity to 0.

<HeaderImageScrollView
  minOverlayOpacity={0}
  maxOverlayOpacity={0}
  {/* ... */}
/>

How to remove the image zomming on scroll down

You have two solutions :

  1. You can use the disableHeaderGrow props. It will keep the ios elastic scroll effect.
  2. You can also use the bounces={false} props from the scroll view.

Results :

disableHeaderGrow bounces={false}
react-native-image-header-scroll-view demo disableHeaderGrow react-native-image-header-scroll-view demo bounces

Contributing

All contributions are welcomed, that might be either adding new features, doing some refaco of the exisiting code or fixing bugs.

How to contribute

  1. Fork the project & clone locally. Follow the initial setup here.
  2. Create a branch, naming it either a feature or bug: git checkout -b feature/that-new-feature or bug/fixing-that-bug
  3. Code and commit your changes. Write a good commit message. Best would be to use git commitizen
  4. Test your changes in the example repository
  5. Push to the branch: git push origin feature/that-new-feature
  6. Create a pull request for your branch 🎉

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