react-native/Libraries/Components/ScrollView/ScrollView.js

1031 lines
36 KiB
JavaScript

/**
* Copyright (c) Facebook, Inc. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @format
* @flow
*/
'use strict';
const AnimatedImplementation = require('AnimatedImplementation');
const Platform = require('Platform');
const React = require('React');
const ReactNative = require('ReactNative');
const ScrollResponder = require('ScrollResponder');
const ScrollViewStickyHeader = require('ScrollViewStickyHeader');
const StyleSheet = require('StyleSheet');
const View = require('View');
const InternalScrollViewType = require('InternalScrollViewType');
const createReactClass = require('create-react-class');
const dismissKeyboard = require('dismissKeyboard');
const flattenStyle = require('flattenStyle');
const invariant = require('fbjs/lib/invariant');
const processDecelerationRate = require('processDecelerationRate');
const requireNativeComponent = require('requireNativeComponent');
const warning = require('fbjs/lib/warning');
const resolveAssetSource = require('resolveAssetSource');
import type {PressEvent} from 'CoreEventTypes';
import type {EdgeInsetsProp} from 'EdgeInsetsPropType';
import type {NativeMethodsMixinType} from 'ReactNativeTypes';
import type {ViewStyleProp} from 'StyleSheet';
import type {ViewProps} from 'ViewPropTypes';
import type {PointProp} from 'PointPropType';
import type {ColorValue} from 'StyleSheetTypes';
let AndroidScrollView;
let AndroidHorizontalScrollContentView;
let AndroidHorizontalScrollView;
let RCTScrollView;
let RCTScrollContentView;
if (Platform.OS === 'android') {
AndroidScrollView = requireNativeComponent('RCTScrollView');
AndroidHorizontalScrollView = requireNativeComponent(
'AndroidHorizontalScrollView',
);
AndroidHorizontalScrollContentView = requireNativeComponent(
'AndroidHorizontalScrollContentView',
);
} else if (Platform.OS === 'ios') {
RCTScrollView = requireNativeComponent('RCTScrollView');
RCTScrollContentView = requireNativeComponent('RCTScrollContentView');
} else {
RCTScrollView = requireNativeComponent('RCTScrollView');
RCTScrollContentView = requireNativeComponent('RCTScrollContentView');
}
type TouchableProps = $ReadOnly<{|
onTouchStart?: (event: PressEvent) => void,
onTouchMove?: (event: PressEvent) => void,
onTouchEnd?: (event: PressEvent) => void,
onTouchCancel?: (event: PressEvent) => void,
onTouchEndCapture?: (event: PressEvent) => void,
|}>;
type IOSProps = $ReadOnly<{|
/**
* Controls whether iOS should automatically adjust the content inset
* for scroll views that are placed behind a navigation bar or
* tab bar/ toolbar. The default value is true.
* @platform ios
*/
automaticallyAdjustContentInsets?: ?boolean,
/**
* The amount by which the scroll view content is inset from the edges
* of the scroll view. Defaults to `{top: 0, left: 0, bottom: 0, right: 0}`.
* @platform ios
*/
contentInset?: ?EdgeInsetsProp,
/**
* Used to manually set the starting scroll offset.
* The default value is `{x: 0, y: 0}`.
* @platform ios
*/
contentOffset?: ?PointProp,
/**
* When true, the scroll view bounces when it reaches the end of the
* content if the content is larger then the scroll view along the axis of
* the scroll direction. When false, it disables all bouncing even if
* the `alwaysBounce*` props are true. The default value is true.
* @platform ios
*/
bounces?: ?boolean,
/**
* When true, gestures can drive zoom past min/max and the zoom will animate
* to the min/max value at gesture end, otherwise the zoom will not exceed
* the limits.
* @platform ios
*/
bouncesZoom?: ?boolean,
/**
* When true, the scroll view bounces horizontally when it reaches the end
* even if the content is smaller than the scroll view itself. The default
* value is true when `horizontal={true}` and false otherwise.
* @platform ios
*/
alwaysBounceHorizontal?: ?boolean,
/**
* When true, the scroll view bounces vertically when it reaches the end
* even if the content is smaller than the scroll view itself. The default
* value is false when `horizontal={true}` and true otherwise.
* @platform ios
*/
alwaysBounceVertical?: ?boolean,
/**
* When true, the scroll view automatically centers the content when the
* content is smaller than the scroll view bounds; when the content is
* larger than the scroll view, this property has no effect. The default
* value is false.
* @platform ios
*/
centerContent?: ?boolean,
/**
* The style of the scroll indicators.
*
* - `'default'` (the default), same as `black`.
* - `'black'`, scroll indicator is black. This style is good against a light background.
* - `'white'`, scroll indicator is white. This style is good against a dark background.
*
* @platform ios
*/
indicatorStyle?: ?('default' | 'black' | 'white'),
/**
* When true, the ScrollView will try to lock to only vertical or horizontal
* scrolling while dragging. The default value is false.
* @platform ios
*/
directionalLockEnabled?: ?boolean,
/**
* When false, once tracking starts, won't try to drag if the touch moves.
* The default value is true.
* @platform ios
*/
canCancelContentTouches?: ?boolean,
/**
* When set, the scroll view will adjust the scroll position so that the first child that is
* currently visible and at or beyond `minIndexForVisible` will not change position. This is
* useful for lists that are loading content in both directions, e.g. a chat thread, where new
* messages coming in might otherwise cause the scroll position to jump. A value of 0 is common,
* but other values such as 1 can be used to skip loading spinners or other content that should
* not maintain position.
*
* The optional `autoscrollToTopThreshold` can be used to make the content automatically scroll
* to the top after making the adjustment if the user was within the threshold of the top before
* the adjustment was made. This is also useful for chat-like applications where you want to see
* new messages scroll into place, but not if the user has scrolled up a ways and it would be
* disruptive to scroll a bunch.
*
* Caveat 1: Reordering elements in the scrollview with this enabled will probably cause
* jumpiness and jank. It can be fixed, but there are currently no plans to do so. For now,
* don't re-order the content of any ScrollViews or Lists that use this feature.
*
* Caveat 2: This simply uses `contentOffset` and `frame.origin` in native code to compute
* visibility. Occlusion, transforms, and other complexity won't be taken into account as to
* whether content is "visible" or not.
*
* @platform ios
*/
maintainVisibleContentPosition?: ?$ReadOnly<{|
minIndexForVisible: number,
autoscrollToTopThreshold?: ?number,
|}>,
/**
* The maximum allowed zoom scale. The default value is 1.0.
* @platform ios
*/
maximumZoomScale?: ?number,
/**
* The minimum allowed zoom scale. The default value is 1.0.
* @platform ios
*/
minimumZoomScale?: ?number,
/**
* When true, ScrollView allows use of pinch gestures to zoom in and out.
* The default value is true.
* @platform ios
*/
pinchGestureEnabled?: ?boolean,
/**
* This controls how often the scroll event will be fired while scrolling
* (as a time interval in ms). A lower number yields better accuracy for code
* that is tracking the scroll position, but can lead to scroll performance
* problems due to the volume of information being send over the bridge.
* You will not notice a difference between values set between 1-16 as the
* JS run loop is synced to the screen refresh rate. If you do not need precise
* scroll position tracking, set this value higher to limit the information
* being sent across the bridge. The default value is zero, which results in
* the scroll event being sent only once each time the view is scrolled.
* @platform ios
*/
scrollEventThrottle?: ?number,
/**
* The amount by which the scroll view indicators are inset from the edges
* of the scroll view. This should normally be set to the same value as
* the `contentInset`. Defaults to `{0, 0, 0, 0}`.
* @platform ios
*/
scrollIndicatorInsets?: ?EdgeInsetsProp,
/**
* When true, the scroll view scrolls to top when the status bar is tapped.
* The default value is true.
* @platform ios
*/
scrollsToTop?: ?boolean,
/**
* Fires when the scroll view scrolls to top after the status bar has been tapped
* @platform ios
*/
onScrollToTop?: ?Function,
/**
* When true, shows a horizontal scroll indicator.
* The default value is true.
*/
showsHorizontalScrollIndicator?: ?boolean,
/**
* When `snapToInterval` is set, `snapToAlignment` will define the relationship
* of the snapping to the scroll view.
*
* - `'start'` (the default) will align the snap at the left (horizontal) or top (vertical)
* - `'center'` will align the snap in the center
* - `'end'` will align the snap at the right (horizontal) or bottom (vertical)
*
* @platform ios
*/
snapToAlignment?: ?('start' | 'center' | 'end'),
/**
* The current scale of the scroll view content. The default value is 1.0.
* @platform ios
*/
zoomScale?: ?number,
/**
* This property specifies how the safe area insets are used to modify the
* content area of the scroll view. The default value of this property is
* "never". Available on iOS 11 and later.
* @platform ios
*/
contentInsetAdjustmentBehavior?: ?(
| 'automatic'
| 'scrollableAxes'
| 'never'
| 'always'
),
/**
* When true, ScrollView will emit updateChildFrames data in scroll events,
* otherwise will not compute or emit child frame data. This only exists
* to support legacy issues, `onLayout` should be used instead to retrieve
* frame data.
* The default value is false.
* @platform ios
*/
DEPRECATED_sendUpdatedChildFrames?: ?boolean,
|}>;
type AndroidProps = $ReadOnly<{|
/**
* Enables nested scrolling for Android API level 21+.
* Nested scrolling is supported by default on iOS
* @platform android
*/
nestedScrollEnabled?: ?boolean,
/**
* Sometimes a scrollview takes up more space than its content fills. When this is
* the case, this prop will fill the rest of the scrollview with a color to avoid setting
* a background and creating unnecessary overdraw. This is an advanced optimization
* that is not needed in the general case.
* @platform android
*/
endFillColor?: ?ColorValue,
/**
* Tag used to log scroll performance on this scroll view. Will force
* momentum events to be turned on (see sendMomentumEvents). This doesn't do
* anything out of the box and you need to implement a custom native
* FpsListener for it to be useful.
* @platform android
*/
scrollPerfTag?: ?string,
/**
* Used to override default value of overScroll mode.
*
* Possible values:
*
* - `'auto'` - Default value, allow a user to over-scroll
* this view only if the content is large enough to meaningfully scroll.
* - `'always'` - Always allow a user to over-scroll this view.
* - `'never'` - Never allow a user to over-scroll this view.
*
* @platform android
*/
overScrollMode?: ?('auto' | 'always' | 'never'),
|}>;
type VRProps = $ReadOnly<{|
/**
* Optionally an image can be used for the scroll bar thumb. This will
* override the color. While the image is loading or the image fails to
* load the color will be used instead. Use an alpha of 0 in the color
* to avoid seeing it while the image is loading.
*
* - `uri` - a string representing the resource identifier for the image, which
* should be either a local file path or the name of a static image resource
* - `number` - Opaque type returned by something like
* `import IMAGE from './image.jpg'`.
* @platform vr
*/
scrollBarThumbImage?: ?($ReadOnly<{||}> | number), // Opaque type returned by import IMAGE from './image.jpg'
|}>;
export type Props = $ReadOnly<{|
...ViewProps,
...TouchableProps,
...IOSProps,
...AndroidProps,
...VRProps,
/**
* These styles will be applied to the scroll view content container which
* wraps all of the child views. Example:
*
* ```
* return (
* <ScrollView contentContainerStyle={styles.contentContainer}>
* </ScrollView>
* );
* ...
* const styles = StyleSheet.create({
* contentContainer: {
* paddingVertical: 20
* }
* });
* ```
*/
contentContainerStyle?: ?ViewStyleProp,
/**
* A floating-point number that determines how quickly the scroll view
* decelerates after the user lifts their finger. You may also use string
* shortcuts `"normal"` and `"fast"` which match the underlying iOS settings
* for `UIScrollViewDecelerationRateNormal` and
* `UIScrollViewDecelerationRateFast` respectively.
*
* - `'normal'`: 0.998 on iOS, 0.985 on Android (the default)
* - `'fast'`: 0.99 on iOS, 0.9 on Android
*/
decelerationRate?: ?('fast' | 'normal' | number),
/**
* When true, the scroll view's children are arranged horizontally in a row
* instead of vertically in a column. The default value is false.
*/
horizontal?: ?boolean,
/**
* If sticky headers should stick at the bottom instead of the top of the
* ScrollView. This is usually used with inverted ScrollViews.
*/
invertStickyHeaders?: ?boolean,
/**
* Determines whether the keyboard gets dismissed in response to a drag.
*
* *Cross platform*
*
* - `'none'` (the default), drags do not dismiss the keyboard.
* - `'on-drag'`, the keyboard is dismissed when a drag begins.
*
* *iOS Only*
*
* - `'interactive'`, the keyboard is dismissed interactively with the drag and moves in
* synchrony with the touch; dragging upwards cancels the dismissal.
* On android this is not supported and it will have the same behavior as 'none'.
*/
keyboardDismissMode?: ?(
| 'none' // default
| 'on-drag' // cross-platform
| 'interactive'
), // ios only
/**
* Determines when the keyboard should stay visible after a tap.
*
* - `'never'` (the default), tapping outside of the focused text input when the keyboard
* is up dismisses the keyboard. When this happens, children won't receive the tap.
* - `'always'`, the keyboard will not dismiss automatically, and the scroll view will not
* catch taps, but children of the scroll view can catch taps.
* - `'handled'`, the keyboard will not dismiss automatically when the tap was handled by
* a children, (or captured by an ancestor).
* - `false`, deprecated, use 'never' instead
* - `true`, deprecated, use 'always' instead
*/
// $FlowFixMe(site=react_native_fb) Issues found when typing ScrollView
keyboardShouldPersistTaps?: ?('always' | 'never' | 'handled' | false | true),
/**
* Called when the momentum scroll starts (scroll which occurs as the ScrollView glides to a stop).
*/
onMomentumScrollBegin?: ?Function,
/**
* Called when the momentum scroll ends (scroll which occurs as the ScrollView glides to a stop).
*/
onMomentumScrollEnd?: ?Function,
/**
* Fires at most once per frame during scrolling. The frequency of the
* events can be controlled using the `scrollEventThrottle` prop.
*/
onScroll?: ?Function,
/**
* Called when the user begins to drag the scroll view.
*/
onScrollBeginDrag?: ?Function,
/**
* Called when the user stops dragging the scroll view and it either stops
* or begins to glide.
*/
onScrollEndDrag?: ?Function,
/**
* Called when scrollable content view of the ScrollView changes.
*
* Handler function is passed the content width and content height as parameters:
* `(contentWidth, contentHeight)`
*
* It's implemented using onLayout handler attached to the content container
* which this ScrollView renders.
*/
onContentSizeChange?: ?Function,
onKeyboardDidShow?: (event: PressEvent) => void,
/**
* When true, the scroll view stops on multiples of the scroll view's size
* when scrolling. This can be used for horizontal pagination. The default
* value is false.
*
* Note: Vertical pagination is not supported on Android.
*/
pagingEnabled?: ?boolean,
/**
* When false, the view cannot be scrolled via touch interaction.
* The default value is true.
*
* Note that the view can always be scrolled by calling `scrollTo`.
*/
scrollEnabled?: ?boolean,
/**
* When true, shows a vertical scroll indicator.
* The default value is true.
*/
showsVerticalScrollIndicator?: ?boolean,
/**
* An array of child indices determining which children get docked to the
* top of the screen when scrolling. For example, passing
* `stickyHeaderIndices={[0]}` will cause the first child to be fixed to the
* top of the scroll view. This property is not supported in conjunction
* with `horizontal={true}`.
*/
stickyHeaderIndices?: ?$ReadOnlyArray<number>,
/**
* When set, causes the scroll view to stop at multiples of the value of
* `snapToInterval`. This can be used for paginating through children
* that have lengths smaller than the scroll view. Typically used in
* combination with `snapToAlignment` and `decelerationRate="fast"`.
*
* Overrides less configurable `pagingEnabled` prop.
*/
snapToInterval?: ?number,
/**
* When set, causes the scroll view to stop at the defined offsets.
* This can be used for paginating through variously sized children
* that have lengths smaller than the scroll view. Typically used in
* combination with `decelerationRate="fast"`.
*
* Overrides less configurable `pagingEnabled` and `snapToInterval` props.
*/
snapToOffsets?: ?$ReadOnlyArray<number>,
/**
* Use in conjuction with `snapToOffsets`. By default, the beginning
* of the list counts as a snap offset. Set `snapToStart` to false to disable
* this behavior and allow the list to scroll freely between its start and
* the first `snapToOffsets` offset.
* The default value is true.
*/
snapToStart?: ?boolean,
/**
* Use in conjuction with `snapToOffsets`. By default, the end
* of the list counts as a snap offset. Set `snapToEnd` to false to disable
* this behavior and allow the list to scroll freely between its end and
* the last `snapToOffsets` offset.
* The default value is true.
*/
snapToEnd?: ?boolean,
/**
* Experimental: When true, offscreen child views (whose `overflow` value is
* `hidden`) are removed from their native backing superview when offscreen.
* This can improve scrolling performance on long lists. The default value is
* true.
*/
removeClippedSubviews?: ?boolean,
/**
* A RefreshControl component, used to provide pull-to-refresh
* functionality for the ScrollView. Only works for vertical ScrollViews
* (`horizontal` prop must be `false`).
*
* See [RefreshControl](docs/refreshcontrol.html).
*/
refreshControl?: ?React.Element<any>,
children?: React.Node,
|}>;
/**
* Component that wraps platform ScrollView while providing
* integration with touch locking "responder" system.
*
* Keep in mind that ScrollViews must have a bounded height in order to work,
* since they contain unbounded-height children into a bounded container (via
* a scroll interaction). In order to bound the height of a ScrollView, either
* set the height of the view directly (discouraged) or make sure all parent
* views have bounded height. Forgetting to transfer `{flex: 1}` down the
* view stack can lead to errors here, which the element inspector makes
* easy to debug.
*
* Doesn't yet support other contained responders from blocking this scroll
* view from becoming the responder.
*
*
* `<ScrollView>` vs [`<FlatList>`](/react-native/docs/flatlist.html) - which one to use?
*
* `ScrollView` simply renders all its react child components at once. That
* makes it very easy to understand and use.
*
* On the other hand, this has a performance downside. Imagine you have a very
* long list of items you want to display, maybe several screens worth of
* content. Creating JS components and native views for everything all at once,
* much of which may not even be shown, will contribute to slow rendering and
* increased memory usage.
*
* This is where `FlatList` comes into play. `FlatList` renders items lazily,
* just when they are about to appear, and removes items that scroll way off
* screen to save memory and processing time.
*
* `FlatList` is also handy if you want to render separators between your items,
* multiple columns, infinite scroll loading, or any number of other features it
* supports out of the box.
*/
const ScrollView = createReactClass({
displayName: 'ScrollView',
mixins: [ScrollResponder.Mixin],
_scrollAnimatedValue: (new AnimatedImplementation.Value(
0,
): AnimatedImplementation.Value),
_scrollAnimatedValueAttachment: (null: ?{detach: () => void}),
_stickyHeaderRefs: (new Map(): Map<number, ScrollViewStickyHeader>),
_headerLayoutYs: (new Map(): Map<string, number>),
getInitialState: function() {
return {
...this.scrollResponderMixinGetInitialState(),
layoutHeight: null,
};
},
UNSAFE_componentWillMount: function() {
this._scrollAnimatedValue = new AnimatedImplementation.Value(
this.props.contentOffset ? this.props.contentOffset.y : 0,
);
this._scrollAnimatedValue.setOffset(
this.props.contentInset ? this.props.contentInset.top : 0,
);
this._stickyHeaderRefs = new Map();
this._headerLayoutYs = new Map();
},
componentDidMount: function() {
this._updateAnimatedNodeAttachment();
},
componentDidUpdate: function() {
this._updateAnimatedNodeAttachment();
},
componentWillUnmount: function() {
if (this._scrollAnimatedValueAttachment) {
this._scrollAnimatedValueAttachment.detach();
}
},
setNativeProps: function(props: Object) {
this._scrollViewRef && this._scrollViewRef.setNativeProps(props);
},
/**
* Returns a reference to the underlying scroll responder, which supports
* operations like `scrollTo`. All ScrollView-like components should
* implement this method so that they can be composed while providing access
* to the underlying scroll responder's methods.
*/
getScrollResponder: function(): ScrollView {
return this;
},
getScrollableNode: function(): any {
return ReactNative.findNodeHandle(this._scrollViewRef);
},
getInnerViewNode: function(): any {
return ReactNative.findNodeHandle(this._innerViewRef);
},
/**
* Scrolls to a given x, y offset, either immediately or with a smooth animation.
*
* Example:
*
* `scrollTo({x: 0, y: 0, animated: true})`
*
* Note: The weird function signature is due to the fact that, for historical reasons,
* the function also accepts separate arguments as an alternative to the options object.
* This is deprecated due to ambiguity (y before x), and SHOULD NOT BE USED.
*/
scrollTo: function(
y?: number | {x?: number, y?: number, animated?: boolean},
x?: number,
animated?: boolean,
) {
if (typeof y === 'number') {
console.warn(
'`scrollTo(y, x, animated)` is deprecated. Use `scrollTo({x: 5, y: 5, ' +
'animated: true})` instead.',
);
} else {
({x, y, animated} = y || {});
}
this.getScrollResponder().scrollResponderScrollTo({
x: x || 0,
y: y || 0,
animated: animated !== false,
});
},
/**
* If this is a vertical ScrollView scrolls to the bottom.
* If this is a horizontal ScrollView scrolls to the right.
*
* Use `scrollToEnd({animated: true})` for smooth animated scrolling,
* `scrollToEnd({animated: false})` for immediate scrolling.
* If no options are passed, `animated` defaults to true.
*/
scrollToEnd: function(options?: {animated?: boolean}) {
// Default to true
const animated = (options && options.animated) !== false;
this.getScrollResponder().scrollResponderScrollToEnd({
animated: animated,
});
},
/**
* Deprecated, use `scrollTo` instead.
*/
scrollWithoutAnimationTo: function(y: number = 0, x: number = 0) {
console.warn(
'`scrollWithoutAnimationTo` is deprecated. Use `scrollTo` instead',
);
this.scrollTo({x, y, animated: false});
},
/**
* Displays the scroll indicators momentarily.
*
* @platform ios
*/
flashScrollIndicators: function() {
this.getScrollResponder().scrollResponderFlashScrollIndicators();
},
_getKeyForIndex: function(index, childArray) {
// $FlowFixMe Invalid prop usage
const child = childArray[index];
return child && child.key;
},
_updateAnimatedNodeAttachment: function() {
if (this._scrollAnimatedValueAttachment) {
this._scrollAnimatedValueAttachment.detach();
}
if (
this.props.stickyHeaderIndices &&
this.props.stickyHeaderIndices.length > 0
) {
this._scrollAnimatedValueAttachment = AnimatedImplementation.attachNativeEvent(
this._scrollViewRef,
'onScroll',
[{nativeEvent: {contentOffset: {y: this._scrollAnimatedValue}}}],
);
}
},
_setStickyHeaderRef: function(key, ref) {
if (ref) {
this._stickyHeaderRefs.set(key, ref);
} else {
this._stickyHeaderRefs.delete(key);
}
},
_onStickyHeaderLayout: function(index, event, key) {
if (!this.props.stickyHeaderIndices) {
return;
}
const childArray = React.Children.toArray(this.props.children);
if (key !== this._getKeyForIndex(index, childArray)) {
// ignore stale layout update
return;
}
const layoutY = event.nativeEvent.layout.y;
this._headerLayoutYs.set(key, layoutY);
const indexOfIndex = this.props.stickyHeaderIndices.indexOf(index);
const previousHeaderIndex = this.props.stickyHeaderIndices[
indexOfIndex - 1
];
if (previousHeaderIndex != null) {
const previousHeader = this._stickyHeaderRefs.get(
this._getKeyForIndex(previousHeaderIndex, childArray),
);
previousHeader && previousHeader.setNextHeaderY(layoutY);
}
},
_handleScroll: function(e: Object) {
if (__DEV__) {
if (
this.props.onScroll &&
this.props.scrollEventThrottle == null &&
Platform.OS === 'ios'
) {
console.log(
'You specified `onScroll` on a <ScrollView> but not ' +
'`scrollEventThrottle`. You will only receive one event. ' +
'Using `16` you get all the events but be aware that it may ' +
"cause frame drops, use a bigger number if you don't need as " +
'much precision.',
);
}
}
if (Platform.OS === 'android') {
if (
this.props.keyboardDismissMode === 'on-drag' &&
this.state.isTouching
) {
dismissKeyboard();
}
}
this.scrollResponderHandleScroll(e);
},
_handleLayout: function(e: Object) {
if (this.props.invertStickyHeaders) {
this.setState({layoutHeight: e.nativeEvent.layout.height});
}
if (this.props.onLayout) {
this.props.onLayout(e);
}
},
_handleContentOnLayout: function(e: Object) {
const {width, height} = e.nativeEvent.layout;
this.props.onContentSizeChange &&
this.props.onContentSizeChange(width, height);
},
_scrollViewRef: (null: ?ScrollView),
_setScrollViewRef: function(ref: ?ScrollView) {
this._scrollViewRef = ref;
},
_innerViewRef: (null: ?NativeMethodsMixinType),
_setInnerViewRef: function(ref: ?NativeMethodsMixinType) {
this._innerViewRef = ref;
},
render: function() {
let ScrollViewClass;
let ScrollContentContainerViewClass;
if (Platform.OS === 'android') {
if (this.props.horizontal) {
ScrollViewClass = AndroidHorizontalScrollView;
ScrollContentContainerViewClass = AndroidHorizontalScrollContentView;
} else {
ScrollViewClass = AndroidScrollView;
ScrollContentContainerViewClass = View;
}
} else {
ScrollViewClass = RCTScrollView;
ScrollContentContainerViewClass = RCTScrollContentView;
}
invariant(
ScrollViewClass !== undefined,
'ScrollViewClass must not be undefined',
);
invariant(
ScrollContentContainerViewClass !== undefined,
'ScrollContentContainerViewClass must not be undefined',
);
const contentContainerStyle = [
this.props.horizontal && styles.contentContainerHorizontal,
this.props.contentContainerStyle,
];
if (__DEV__ && this.props.style) {
const style = flattenStyle(this.props.style);
const childLayoutProps = ['alignItems', 'justifyContent'].filter(
prop => style && style[prop] !== undefined,
);
invariant(
childLayoutProps.length === 0,
'ScrollView child layout (' +
JSON.stringify(childLayoutProps) +
') must be applied through the contentContainerStyle prop.',
);
}
let contentSizeChangeProps = {};
if (this.props.onContentSizeChange) {
contentSizeChangeProps = {
onLayout: this._handleContentOnLayout,
};
}
const {stickyHeaderIndices} = this.props;
const hasStickyHeaders =
stickyHeaderIndices && stickyHeaderIndices.length > 0;
const childArray =
hasStickyHeaders && React.Children.toArray(this.props.children);
const children = hasStickyHeaders
? // $FlowFixMe Invalid prop usage
childArray.map((child, index) => {
const indexOfIndex = child ? stickyHeaderIndices.indexOf(index) : -1;
if (indexOfIndex > -1) {
const key = child.key;
const nextIndex = stickyHeaderIndices[indexOfIndex + 1];
return (
<ScrollViewStickyHeader
key={key}
ref={ref => this._setStickyHeaderRef(key, ref)}
nextHeaderLayoutY={this._headerLayoutYs.get(
this._getKeyForIndex(nextIndex, childArray),
)}
onLayout={event =>
this._onStickyHeaderLayout(index, event, key)
}
scrollAnimatedValue={this._scrollAnimatedValue}
inverted={this.props.invertStickyHeaders}
scrollViewHeight={this.state.layoutHeight}>
{child}
</ScrollViewStickyHeader>
);
} else {
return child;
}
})
: this.props.children;
const contentContainer = (
<ScrollContentContainerViewClass
{...contentSizeChangeProps}
// $FlowFixMe Invalid prop usage
ref={this._setInnerViewRef}
style={contentContainerStyle}
removeClippedSubviews={
// Subview clipping causes issues with sticky headers on Android and
// would be hard to fix properly in a performant way.
Platform.OS === 'android' && hasStickyHeaders
? false
: this.props.removeClippedSubviews
}
collapsable={false}>
{children}
</ScrollContentContainerViewClass>
);
const alwaysBounceHorizontal =
this.props.alwaysBounceHorizontal !== undefined
? this.props.alwaysBounceHorizontal
: this.props.horizontal;
const alwaysBounceVertical =
this.props.alwaysBounceVertical !== undefined
? this.props.alwaysBounceVertical
: !this.props.horizontal;
const DEPRECATED_sendUpdatedChildFrames = !!this.props
.DEPRECATED_sendUpdatedChildFrames;
const baseStyle = this.props.horizontal
? styles.baseHorizontal
: styles.baseVertical;
const props = {
...this.props,
alwaysBounceHorizontal,
alwaysBounceVertical,
style: ([baseStyle, this.props.style]: ?Array<any>),
// Override the onContentSizeChange from props, since this event can
// bubble up from TextInputs
onContentSizeChange: null,
onLayout: this._handleLayout,
onMomentumScrollBegin: this.scrollResponderHandleMomentumScrollBegin,
onMomentumScrollEnd: this.scrollResponderHandleMomentumScrollEnd,
onResponderGrant: this.scrollResponderHandleResponderGrant,
onResponderReject: this.scrollResponderHandleResponderReject,
onResponderRelease: this.scrollResponderHandleResponderRelease,
// $FlowFixMe
onResponderTerminate: this.scrollResponderHandleTerminate,
onResponderTerminationRequest: this
.scrollResponderHandleTerminationRequest,
onScroll: this._handleScroll,
onScrollBeginDrag: this.scrollResponderHandleScrollBeginDrag,
onScrollEndDrag: this.scrollResponderHandleScrollEndDrag,
onScrollShouldSetResponder: this
.scrollResponderHandleScrollShouldSetResponder,
onStartShouldSetResponder: this
.scrollResponderHandleStartShouldSetResponder,
onStartShouldSetResponderCapture: this
.scrollResponderHandleStartShouldSetResponderCapture,
onTouchEnd: this.scrollResponderHandleTouchEnd,
onTouchMove: this.scrollResponderHandleTouchMove,
onTouchStart: this.scrollResponderHandleTouchStart,
onTouchCancel: this.scrollResponderHandleTouchCancel,
scrollBarThumbImage: resolveAssetSource(this.props.scrollBarThumbImage),
scrollEventThrottle: hasStickyHeaders
? 1
: this.props.scrollEventThrottle,
sendMomentumEvents:
this.props.onMomentumScrollBegin || this.props.onMomentumScrollEnd
? true
: false,
DEPRECATED_sendUpdatedChildFrames,
// default to true
snapToStart: this.props.snapToStart !== false,
// default to true
snapToEnd: this.props.snapToEnd !== false,
// pagingEnabled is overridden by snapToInterval / snapToOffsets
pagingEnabled: Platform.select({
// on iOS, pagingEnabled must be set to false to have snapToInterval / snapToOffsets work
ios:
this.props.pagingEnabled &&
this.props.snapToInterval == null &&
this.props.snapToOffsets == null,
// on Android, pagingEnabled must be set to true to have snapToInterval / snapToOffsets work
android:
this.props.pagingEnabled ||
this.props.snapToInterval != null ||
this.props.snapToOffsets != null,
}),
};
const {decelerationRate} = this.props;
if (decelerationRate != null) {
props.decelerationRate = processDecelerationRate(decelerationRate);
}
const refreshControl = this.props.refreshControl;
if (refreshControl) {
if (Platform.OS === 'ios') {
// On iOS the RefreshControl is a child of the ScrollView.
// tvOS lacks native support for RefreshControl, so don't include it in that case
return (
<ScrollViewClass {...props} ref={this._setScrollViewRef}>
{Platform.isTV ? null : refreshControl}
{contentContainer}
</ScrollViewClass>
);
} else if (Platform.OS === 'android') {
// On Android wrap the ScrollView with a AndroidSwipeRefreshLayout.
// Since the ScrollView is wrapped add the style props to the
// AndroidSwipeRefreshLayout and use flex: 1 for the ScrollView.
// Note: we should only apply props.style on the wrapper
// however, the ScrollView still needs the baseStyle to be scrollable
return React.cloneElement(
refreshControl,
{style: props.style},
<ScrollViewClass
{...props}
style={baseStyle}
ref={this._setScrollViewRef}>
{contentContainer}
</ScrollViewClass>,
);
}
}
return (
<ScrollViewClass {...props} ref={this._setScrollViewRef}>
{contentContainer}
</ScrollViewClass>
);
},
});
const TypedScrollView = ((ScrollView: any): Class<
InternalScrollViewType<Props>,
>);
const styles = StyleSheet.create({
baseVertical: {
flexGrow: 1,
flexShrink: 1,
flexDirection: 'column',
overflow: 'scroll',
},
baseHorizontal: {
flexGrow: 1,
flexShrink: 1,
flexDirection: 'row',
overflow: 'scroll',
},
contentContainerHorizontal: {
flexDirection: 'row',
},
});
module.exports = TypedScrollView;