1143 строки
40 KiB
JavaScript
1143 строки
40 KiB
JavaScript
/**
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* Copyright (c) Facebook, Inc. and its affiliates.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*
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* @format
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* @flow strict-local
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*/
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'use strict';
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const AnimatedImplementation = require('AnimatedImplementation');
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const Platform = require('Platform');
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const React = require('React');
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const ReactNative = require('ReactNative');
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const ScrollResponder = require('ScrollResponder');
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const ScrollViewStickyHeader = require('ScrollViewStickyHeader');
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const StyleSheet = require('StyleSheet');
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const View = require('View');
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const dismissKeyboard = require('dismissKeyboard');
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const flattenStyle = require('flattenStyle');
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const invariant = require('invariant');
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const processDecelerationRate = require('processDecelerationRate');
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const requireNativeComponent = require('requireNativeComponent');
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const resolveAssetSource = require('resolveAssetSource');
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import type {PressEvent, ScrollEvent, LayoutEvent} from 'CoreEventTypes';
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import type {EdgeInsetsProp} from 'EdgeInsetsPropType';
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import type {NativeMethodsMixinType} from 'ReactNativeTypes';
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import type {ViewStyleProp} from 'StyleSheet';
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import type {ViewProps} from 'ViewPropTypes';
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import type {PointProp} from 'PointPropType';
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import type {ColorValue} from 'StyleSheetTypes';
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import type {State as ScrollResponderState} from 'ScrollResponder';
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let AndroidScrollView;
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let AndroidHorizontalScrollContentView;
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let AndroidHorizontalScrollView;
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let RCTScrollView;
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let RCTScrollContentView;
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if (Platform.OS === 'android') {
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AndroidScrollView = requireNativeComponent('RCTScrollView');
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AndroidHorizontalScrollView = requireNativeComponent(
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'AndroidHorizontalScrollView',
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);
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AndroidHorizontalScrollContentView = requireNativeComponent(
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'AndroidHorizontalScrollContentView',
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);
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} else if (Platform.OS === 'ios') {
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RCTScrollView = requireNativeComponent('RCTScrollView');
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RCTScrollContentView = requireNativeComponent('RCTScrollContentView');
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} else {
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RCTScrollView = requireNativeComponent('RCTScrollView');
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RCTScrollContentView = requireNativeComponent('RCTScrollContentView');
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}
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export type ScrollResponderType = {
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...ScrollView,
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...typeof ScrollResponder.Mixin,
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};
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type TouchableProps = $ReadOnly<{|
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onTouchStart?: (event: PressEvent) => void,
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onTouchMove?: (event: PressEvent) => void,
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onTouchEnd?: (event: PressEvent) => void,
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onTouchCancel?: (event: PressEvent) => void,
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onTouchEndCapture?: (event: PressEvent) => void,
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|}>;
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type IOSProps = $ReadOnly<{|
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/**
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* Controls whether iOS should automatically adjust the content inset
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* for scroll views that are placed behind a navigation bar or
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* tab bar/ toolbar. The default value is true.
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* @platform ios
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*/
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automaticallyAdjustContentInsets?: ?boolean,
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/**
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* The amount by which the scroll view content is inset from the edges
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* of the scroll view. Defaults to `{top: 0, left: 0, bottom: 0, right: 0}`.
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* @platform ios
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*/
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contentInset?: ?EdgeInsetsProp,
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/**
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* Used to manually set the starting scroll offset.
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* The default value is `{x: 0, y: 0}`.
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* @platform ios
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*/
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contentOffset?: ?PointProp,
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/**
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* When true, the scroll view bounces when it reaches the end of the
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* content if the content is larger then the scroll view along the axis of
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* the scroll direction. When false, it disables all bouncing even if
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* the `alwaysBounce*` props are true. The default value is true.
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* @platform ios
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*/
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bounces?: ?boolean,
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/**
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* By default, ScrollView has an active pan responder that hijacks panresponders
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* deeper in the render tree in order to prevent accidental touches while scrolling.
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* However, in certain occasions (such as when using snapToInterval) in a vertical scrollview
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* You may want to disable this behavior in order to prevent the ScrollView from blocking touches
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*/
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disableScrollViewPanResponder?: ?boolean,
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/**
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* When true, gestures can drive zoom past min/max and the zoom will animate
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* to the min/max value at gesture end, otherwise the zoom will not exceed
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* the limits.
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* @platform ios
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*/
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bouncesZoom?: ?boolean,
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/**
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* When true, the scroll view bounces horizontally when it reaches the end
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* even if the content is smaller than the scroll view itself. The default
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* value is true when `horizontal={true}` and false otherwise.
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* @platform ios
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*/
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alwaysBounceHorizontal?: ?boolean,
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/**
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* When true, the scroll view bounces vertically when it reaches the end
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* even if the content is smaller than the scroll view itself. The default
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* value is false when `horizontal={true}` and true otherwise.
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* @platform ios
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*/
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alwaysBounceVertical?: ?boolean,
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/**
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* When true, the scroll view automatically centers the content when the
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* content is smaller than the scroll view bounds; when the content is
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* larger than the scroll view, this property has no effect. The default
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* value is false.
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* @platform ios
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*/
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centerContent?: ?boolean,
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/**
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* The style of the scroll indicators.
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*
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* - `'default'` (the default), same as `black`.
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* - `'black'`, scroll indicator is black. This style is good against a light background.
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* - `'white'`, scroll indicator is white. This style is good against a dark background.
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*
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* @platform ios
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*/
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indicatorStyle?: ?('default' | 'black' | 'white'),
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/**
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* When true, the ScrollView will try to lock to only vertical or horizontal
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* scrolling while dragging. The default value is false.
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* @platform ios
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*/
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directionalLockEnabled?: ?boolean,
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/**
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* When false, once tracking starts, won't try to drag if the touch moves.
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* The default value is true.
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* @platform ios
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*/
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canCancelContentTouches?: ?boolean,
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/**
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* When set, the scroll view will adjust the scroll position so that the first child that is
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* currently visible and at or beyond `minIndexForVisible` will not change position. This is
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* useful for lists that are loading content in both directions, e.g. a chat thread, where new
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* messages coming in might otherwise cause the scroll position to jump. A value of 0 is common,
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* but other values such as 1 can be used to skip loading spinners or other content that should
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* not maintain position.
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*
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* The optional `autoscrollToTopThreshold` can be used to make the content automatically scroll
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* to the top after making the adjustment if the user was within the threshold of the top before
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* the adjustment was made. This is also useful for chat-like applications where you want to see
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* new messages scroll into place, but not if the user has scrolled up a ways and it would be
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* disruptive to scroll a bunch.
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*
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* Caveat 1: Reordering elements in the scrollview with this enabled will probably cause
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* jumpiness and jank. It can be fixed, but there are currently no plans to do so. For now,
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* don't re-order the content of any ScrollViews or Lists that use this feature.
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*
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* Caveat 2: This simply uses `contentOffset` and `frame.origin` in native code to compute
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* visibility. Occlusion, transforms, and other complexity won't be taken into account as to
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* whether content is "visible" or not.
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*
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* @platform ios
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*/
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maintainVisibleContentPosition?: ?$ReadOnly<{|
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minIndexForVisible: number,
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autoscrollToTopThreshold?: ?number,
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|}>,
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/**
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* The maximum allowed zoom scale. The default value is 1.0.
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* @platform ios
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*/
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maximumZoomScale?: ?number,
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/**
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* The minimum allowed zoom scale. The default value is 1.0.
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* @platform ios
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*/
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minimumZoomScale?: ?number,
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/**
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* When true, ScrollView allows use of pinch gestures to zoom in and out.
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* The default value is true.
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* @platform ios
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*/
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pinchGestureEnabled?: ?boolean,
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/**
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* This controls how often the scroll event will be fired while scrolling
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* (as a time interval in ms). A lower number yields better accuracy for code
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* that is tracking the scroll position, but can lead to scroll performance
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* problems due to the volume of information being send over the bridge.
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* You will not notice a difference between values set between 1-16 as the
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* JS run loop is synced to the screen refresh rate. If you do not need precise
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* scroll position tracking, set this value higher to limit the information
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* being sent across the bridge. The default value is zero, which results in
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* the scroll event being sent only once each time the view is scrolled.
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* @platform ios
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*/
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scrollEventThrottle?: ?number,
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/**
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* The amount by which the scroll view indicators are inset from the edges
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* of the scroll view. This should normally be set to the same value as
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* the `contentInset`. Defaults to `{0, 0, 0, 0}`.
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* @platform ios
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*/
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scrollIndicatorInsets?: ?EdgeInsetsProp,
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/**
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* When true, the scroll view scrolls to top when the status bar is tapped.
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* The default value is true.
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* @platform ios
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*/
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scrollsToTop?: ?boolean,
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/**
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* Fires when the scroll view scrolls to top after the status bar has been tapped
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* @platform ios
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*/
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onScrollToTop?: (event: ScrollEvent) => void,
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/**
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* When true, shows a horizontal scroll indicator.
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* The default value is true.
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*/
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showsHorizontalScrollIndicator?: ?boolean,
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/**
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* When `snapToInterval` is set, `snapToAlignment` will define the relationship
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* of the snapping to the scroll view.
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*
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* - `'start'` (the default) will align the snap at the left (horizontal) or top (vertical)
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* - `'center'` will align the snap in the center
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* - `'end'` will align the snap at the right (horizontal) or bottom (vertical)
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*
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* @platform ios
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*/
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snapToAlignment?: ?('start' | 'center' | 'end'),
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/**
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* The current scale of the scroll view content. The default value is 1.0.
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* @platform ios
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*/
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zoomScale?: ?number,
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/**
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* This property specifies how the safe area insets are used to modify the
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* content area of the scroll view. The default value of this property is
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* "never". Available on iOS 11 and later.
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* @platform ios
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*/
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contentInsetAdjustmentBehavior?: ?(
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| 'automatic'
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| 'scrollableAxes'
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| 'never'
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| 'always'
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),
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/**
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* When true, ScrollView will emit updateChildFrames data in scroll events,
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* otherwise will not compute or emit child frame data. This only exists
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* to support legacy issues, `onLayout` should be used instead to retrieve
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* frame data.
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* The default value is false.
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* @platform ios
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*/
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DEPRECATED_sendUpdatedChildFrames?: ?boolean,
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|}>;
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type AndroidProps = $ReadOnly<{|
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/**
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* Enables nested scrolling for Android API level 21+.
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* Nested scrolling is supported by default on iOS
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* @platform android
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*/
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nestedScrollEnabled?: ?boolean,
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/**
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* Sometimes a scrollview takes up more space than its content fills. When this is
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* the case, this prop will fill the rest of the scrollview with a color to avoid setting
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* a background and creating unnecessary overdraw. This is an advanced optimization
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* that is not needed in the general case.
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* @platform android
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*/
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endFillColor?: ?ColorValue,
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/**
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* Tag used to log scroll performance on this scroll view. Will force
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* momentum events to be turned on (see sendMomentumEvents). This doesn't do
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* anything out of the box and you need to implement a custom native
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* FpsListener for it to be useful.
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* @platform android
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*/
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scrollPerfTag?: ?string,
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/**
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* Used to override default value of overScroll mode.
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*
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* Possible values:
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*
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* - `'auto'` - Default value, allow a user to over-scroll
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* this view only if the content is large enough to meaningfully scroll.
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* - `'always'` - Always allow a user to over-scroll this view.
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* - `'never'` - Never allow a user to over-scroll this view.
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*
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* @platform android
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*/
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overScrollMode?: ?('auto' | 'always' | 'never'),
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/**
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* Causes the scrollbars not to turn transparent when they are not in use.
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* The default value is false.
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*
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* @platform android
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*/
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persistentScrollbar?: ?boolean,
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|}>;
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type VRProps = $ReadOnly<{|
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/**
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* Optionally an image can be used for the scroll bar thumb. This will
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* override the color. While the image is loading or the image fails to
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* load the color will be used instead. Use an alpha of 0 in the color
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* to avoid seeing it while the image is loading.
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*
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* - `uri` - a string representing the resource identifier for the image, which
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* should be either a local file path or the name of a static image resource
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* - `number` - Opaque type returned by something like
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* `import IMAGE from './image.jpg'`.
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* @platform vr
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*/
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scrollBarThumbImage?: ?($ReadOnly<{||}> | number), // Opaque type returned by import IMAGE from './image.jpg'
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|}>;
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export type Props = $ReadOnly<{|
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...ViewProps,
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...TouchableProps,
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...IOSProps,
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...AndroidProps,
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...VRProps,
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/**
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* These styles will be applied to the scroll view content container which
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* wraps all of the child views. Example:
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*
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* ```
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* return (
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* <ScrollView contentContainerStyle={styles.contentContainer}>
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* </ScrollView>
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* );
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* ...
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* const styles = StyleSheet.create({
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* contentContainer: {
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* paddingVertical: 20
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* }
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* });
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* ```
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*/
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contentContainerStyle?: ?ViewStyleProp,
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/**
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* A floating-point number that determines how quickly the scroll view
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* decelerates after the user lifts their finger. You may also use string
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* shortcuts `"normal"` and `"fast"` which match the underlying iOS settings
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* for `UIScrollViewDecelerationRateNormal` and
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* `UIScrollViewDecelerationRateFast` respectively.
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*
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* - `'normal'`: 0.998 on iOS, 0.985 on Android (the default)
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* - `'fast'`: 0.99 on iOS, 0.9 on Android
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*/
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decelerationRate?: ?('fast' | 'normal' | number),
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/**
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* When true, the scroll view's children are arranged horizontally in a row
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* instead of vertically in a column. The default value is false.
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*/
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horizontal?: ?boolean,
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/**
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* If sticky headers should stick at the bottom instead of the top of the
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* ScrollView. This is usually used with inverted ScrollViews.
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*/
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invertStickyHeaders?: ?boolean,
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/**
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* Determines whether the keyboard gets dismissed in response to a drag.
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*
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* *Cross platform*
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*
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* - `'none'` (the default), drags do not dismiss the keyboard.
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* - `'on-drag'`, the keyboard is dismissed when a drag begins.
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*
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* *iOS Only*
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*
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* - `'interactive'`, the keyboard is dismissed interactively with the drag and moves in
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* synchrony with the touch; dragging upwards cancels the dismissal.
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* On android this is not supported and it will have the same behavior as 'none'.
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*/
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keyboardDismissMode?: ?(
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| 'none' // default
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| 'on-drag' // cross-platform
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| 'interactive'
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), // ios only
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/**
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* Determines when the keyboard should stay visible after a tap.
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*
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* - `'never'` (the default), tapping outside of the focused text input when the keyboard
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* is up dismisses the keyboard. When this happens, children won't receive the tap.
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* - `'always'`, the keyboard will not dismiss automatically, and the scroll view will not
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* catch taps, but children of the scroll view can catch taps.
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* - `'handled'`, the keyboard will not dismiss automatically when the tap was handled by
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* a children, (or captured by an ancestor).
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* - `false`, deprecated, use 'never' instead
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* - `true`, deprecated, use 'always' instead
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*/
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keyboardShouldPersistTaps?: ?('always' | 'never' | 'handled' | true | false),
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/**
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* Called when the momentum scroll starts (scroll which occurs as the ScrollView glides to a stop).
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*/
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onMomentumScrollBegin?: (event: ScrollEvent) => void,
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/**
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* Called when the momentum scroll ends (scroll which occurs as the ScrollView glides to a stop).
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*/
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onMomentumScrollEnd?: (event: ScrollEvent) => void,
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/**
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* Fires at most once per frame during scrolling. The frequency of the
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* events can be controlled using the `scrollEventThrottle` prop.
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*/
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onScroll?: (event: ScrollEvent) => void,
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/**
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* Called when the user begins to drag the scroll view.
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*/
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onScrollBeginDrag?: (event: ScrollEvent) => void,
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/**
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* Called when the user stops dragging the scroll view and it either stops
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* or begins to glide.
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*/
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onScrollEndDrag?: (event: ScrollEvent) => void,
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/**
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* Called when scrollable content view of the ScrollView changes.
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*
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* Handler function is passed the content width and content height as parameters:
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* `(contentWidth, contentHeight)`
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*
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* It's implemented using onLayout handler attached to the content container
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* which this ScrollView renders.
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*/
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onContentSizeChange?: (contentWidth: number, contentHeight: number) => void,
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onKeyboardDidShow?: (event: PressEvent) => void,
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/**
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* When true, the scroll view stops on multiples of the scroll view's size
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* when scrolling. This can be used for horizontal pagination. The default
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* value is false.
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*
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* Note: Vertical pagination is not supported on Android.
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*/
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pagingEnabled?: ?boolean,
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|
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/**
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* When false, the view cannot be scrolled via touch interaction.
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* The default value is true.
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*
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* Note that the view can always be scrolled by calling `scrollTo`.
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*/
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scrollEnabled?: ?boolean,
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/**
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* When true, shows a vertical scroll indicator.
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* The default value is true.
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*/
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showsVerticalScrollIndicator?: ?boolean,
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/**
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* An array of child indices determining which children get docked to the
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* top of the screen when scrolling. For example, passing
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* `stickyHeaderIndices={[0]}` will cause the first child to be fixed to the
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* top of the scroll view. This property is not supported in conjunction
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* with `horizontal={true}`.
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*/
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stickyHeaderIndices?: ?$ReadOnlyArray<number>,
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/**
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* When set, causes the scroll view to stop at multiples of the value of
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* `snapToInterval`. This can be used for paginating through children
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* that have lengths smaller than the scroll view. Typically used in
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* combination with `snapToAlignment` and `decelerationRate="fast"`.
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*
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* Overrides less configurable `pagingEnabled` prop.
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*/
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snapToInterval?: ?number,
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/**
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* When set, causes the scroll view to stop at the defined offsets.
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* This can be used for paginating through variously sized children
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* that have lengths smaller than the scroll view. Typically used in
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* combination with `decelerationRate="fast"`.
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*
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* 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).
|
|
*/
|
|
// $FlowFixMe - how to handle generic type without existential opereator?
|
|
refreshControl?: ?React.Element<any>,
|
|
children?: React.Node,
|
|
|}>;
|
|
|
|
type State = {|
|
|
layoutHeight: ?number,
|
|
...ScrollResponderState,
|
|
|};
|
|
|
|
function createScrollResponder(
|
|
node: React.ElementRef<typeof ScrollView>,
|
|
): typeof ScrollResponder.Mixin {
|
|
const scrollResponder = {...ScrollResponder.Mixin};
|
|
|
|
for (const key in scrollResponder) {
|
|
if (typeof scrollResponder[key] === 'function') {
|
|
scrollResponder[key] = scrollResponder[key].bind(node);
|
|
}
|
|
}
|
|
|
|
return scrollResponder;
|
|
}
|
|
|
|
/**
|
|
* 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.
|
|
*/
|
|
class ScrollView extends React.Component<Props, State> {
|
|
/**
|
|
* Part 1: Removing ScrollResponder.Mixin:
|
|
*
|
|
* 1. Mixin methods should be flow typed. That's why we create a
|
|
* copy of ScrollResponder.Mixin and attach it to this._scrollResponder.
|
|
* Otherwise, we'd have to manually declare each method on the component
|
|
* class and assign it a flow type.
|
|
* 2. Mixin methods can call component methods, and access the component's
|
|
* props and state. So, we need to bind all mixin methods to the
|
|
* component instance.
|
|
* 3. Continued...
|
|
*/
|
|
_scrollResponder: typeof ScrollResponder.Mixin = createScrollResponder(this);
|
|
|
|
constructor(props: Props) {
|
|
super(props);
|
|
|
|
/**
|
|
* Part 2: Removing ScrollResponder.Mixin
|
|
*
|
|
* 3. Mixin methods access other mixin methods via dynamic dispatch using
|
|
* this. Since mixin methods are bound to the component instance, we need
|
|
* to copy all mixin methods to the component instance. This is also
|
|
* necessary because getScrollResponder() is a public method that returns
|
|
* an object that can be used to execute all scrollResponder methods.
|
|
* Since the object returned from that method is the ScrollView instance,
|
|
* we need to bind all mixin methods to the ScrollView instance.
|
|
*/
|
|
for (const key in ScrollResponder.Mixin) {
|
|
if (
|
|
typeof ScrollResponder.Mixin[key] === 'function' &&
|
|
key.startsWith('scrollResponder')
|
|
) {
|
|
// $FlowFixMe - dynamically adding properties to a class
|
|
(this: any)[key] = ScrollResponder.Mixin[key].bind(this);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Part 3: Removing ScrollResponder.Mixin
|
|
*
|
|
* 4. Mixins can initialize properties and use properties on the component
|
|
* instance.
|
|
*/
|
|
Object.keys(ScrollResponder.Mixin)
|
|
.filter(key => typeof ScrollResponder.Mixin[key] !== 'function')
|
|
.forEach(key => {
|
|
// $FlowFixMe - dynamically adding properties to a class
|
|
(this: any)[key] = ScrollResponder.Mixin[key];
|
|
});
|
|
}
|
|
|
|
_scrollAnimatedValue: AnimatedImplementation.Value = new AnimatedImplementation.Value(
|
|
0,
|
|
);
|
|
_scrollAnimatedValueAttachment: ?{detach: () => void} = null;
|
|
_stickyHeaderRefs: Map<number, ScrollViewStickyHeader> = new Map();
|
|
_headerLayoutYs: Map<string, number> = new Map();
|
|
|
|
state = {
|
|
layoutHeight: null,
|
|
...ScrollResponder.Mixin.scrollResponderMixinGetInitialState(),
|
|
};
|
|
|
|
UNSAFE_componentWillMount() {
|
|
this._scrollResponder.UNSAFE_componentWillMount();
|
|
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();
|
|
}
|
|
|
|
UNSAFE_componentWillReceiveProps(nextProps: Props) {
|
|
const currentContentInsetTop = this.props.contentInset
|
|
? this.props.contentInset.top
|
|
: 0;
|
|
const nextContentInsetTop = nextProps.contentInset
|
|
? nextProps.contentInset.top
|
|
: 0;
|
|
if (currentContentInsetTop !== nextContentInsetTop) {
|
|
this._scrollAnimatedValue.setOffset(nextContentInsetTop || 0);
|
|
}
|
|
}
|
|
|
|
componentDidMount() {
|
|
this._updateAnimatedNodeAttachment();
|
|
}
|
|
|
|
componentDidUpdate() {
|
|
this._updateAnimatedNodeAttachment();
|
|
}
|
|
|
|
componentWillUnmount() {
|
|
this._scrollResponder.componentWillUnmount();
|
|
if (this._scrollAnimatedValueAttachment) {
|
|
this._scrollAnimatedValueAttachment.detach();
|
|
}
|
|
}
|
|
|
|
setNativeProps(props: {[key: string]: mixed}) {
|
|
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(): ScrollResponderType {
|
|
// $FlowFixMe - overriding type to include ScrollResponder.Mixin
|
|
return ((this: any): ScrollResponderType);
|
|
}
|
|
|
|
getScrollableNode(): ?number {
|
|
return ReactNative.findNodeHandle(this._scrollViewRef);
|
|
}
|
|
|
|
getInnerViewNode(): ?number {
|
|
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(
|
|
options?: {x?: number, y?: number, animated?: boolean} | number,
|
|
deprecatedX?: number,
|
|
deprecatedAnimated?: boolean,
|
|
) {
|
|
let x, y, animated;
|
|
if (typeof options === 'number') {
|
|
console.warn(
|
|
'`scrollTo(y, x, animated)` is deprecated. Use `scrollTo({x: 5, y: 5, ' +
|
|
'animated: true})` instead.',
|
|
);
|
|
y = options;
|
|
x = deprecatedX;
|
|
animated = deprecatedAnimated;
|
|
} else if (options) {
|
|
y = options.y;
|
|
x = options.x;
|
|
animated = options.animated;
|
|
}
|
|
this._scrollResponder.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(options?: ?{animated?: boolean}) {
|
|
// Default to true
|
|
const animated = (options && options.animated) !== false;
|
|
this._scrollResponder.scrollResponderScrollToEnd({
|
|
animated: animated,
|
|
});
|
|
}
|
|
|
|
/**
|
|
* Deprecated, use `scrollTo` instead.
|
|
*/
|
|
scrollWithoutAnimationTo(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() {
|
|
this._scrollResponder.scrollResponderFlashScrollIndicators();
|
|
}
|
|
|
|
_getKeyForIndex(index, childArray) {
|
|
const child = childArray[index];
|
|
return child && child.key;
|
|
}
|
|
|
|
_updateAnimatedNodeAttachment() {
|
|
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(key, ref) {
|
|
if (ref) {
|
|
this._stickyHeaderRefs.set(key, ref);
|
|
} else {
|
|
this._stickyHeaderRefs.delete(key);
|
|
}
|
|
}
|
|
|
|
_onStickyHeaderLayout(index, event, key) {
|
|
const {stickyHeaderIndices} = this.props;
|
|
if (!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 = stickyHeaderIndices.indexOf(index);
|
|
const previousHeaderIndex = stickyHeaderIndices[indexOfIndex - 1];
|
|
if (previousHeaderIndex != null) {
|
|
const previousHeader = this._stickyHeaderRefs.get(
|
|
this._getKeyForIndex(previousHeaderIndex, childArray),
|
|
);
|
|
previousHeader && previousHeader.setNextHeaderY(layoutY);
|
|
}
|
|
}
|
|
|
|
_handleScroll = (e: ScrollEvent) => {
|
|
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._scrollResponder.scrollResponderHandleScroll(e);
|
|
};
|
|
|
|
_handleLayout = (e: LayoutEvent) => {
|
|
if (this.props.invertStickyHeaders === true) {
|
|
this.setState({layoutHeight: e.nativeEvent.layout.height});
|
|
}
|
|
if (this.props.onLayout) {
|
|
this.props.onLayout(e);
|
|
}
|
|
};
|
|
|
|
_handleContentOnLayout = (e: LayoutEvent) => {
|
|
const {width, height} = e.nativeEvent.layout;
|
|
this.props.onContentSizeChange &&
|
|
this.props.onContentSizeChange(width, height);
|
|
};
|
|
|
|
_scrollViewRef: ?ScrollView = null;
|
|
_setScrollViewRef = (ref: ?ScrollView) => {
|
|
this._scrollViewRef = ref;
|
|
};
|
|
|
|
_innerViewRef: ?NativeMethodsMixinType = null;
|
|
_setInnerViewRef = (ref: ?NativeMethodsMixinType) => {
|
|
this._innerViewRef = ref;
|
|
};
|
|
|
|
render() {
|
|
let ScrollViewClass;
|
|
let ScrollContentContainerViewClass;
|
|
if (Platform.OS === 'android') {
|
|
if (this.props.horizontal === true) {
|
|
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 === true && styles.contentContainerHorizontal,
|
|
this.props.contentContainerStyle,
|
|
];
|
|
if (__DEV__ && this.props.style !== undefined) {
|
|
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;
|
|
let children = this.props.children;
|
|
|
|
if (stickyHeaderIndices != null && stickyHeaderIndices.length > 0) {
|
|
const childArray = React.Children.toArray(this.props.children);
|
|
|
|
children = 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;
|
|
}
|
|
});
|
|
}
|
|
|
|
const hasStickyHeaders =
|
|
Array.isArray(stickyHeaderIndices) && stickyHeaderIndices.length > 0;
|
|
|
|
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 === true
|
|
? styles.baseHorizontal
|
|
: styles.baseVertical;
|
|
const props = {
|
|
...this.props,
|
|
alwaysBounceHorizontal,
|
|
alwaysBounceVertical,
|
|
style: [baseStyle, this.props.style],
|
|
// Override the onContentSizeChange from props, since this event can
|
|
// bubble up from TextInputs
|
|
onContentSizeChange: null,
|
|
onLayout: this._handleLayout,
|
|
onMomentumScrollBegin: this._scrollResponder
|
|
.scrollResponderHandleMomentumScrollBegin,
|
|
onMomentumScrollEnd: this._scrollResponder
|
|
.scrollResponderHandleMomentumScrollEnd,
|
|
onResponderGrant: this._scrollResponder
|
|
.scrollResponderHandleResponderGrant,
|
|
onResponderReject: this._scrollResponder
|
|
.scrollResponderHandleResponderReject,
|
|
onResponderRelease: this._scrollResponder
|
|
.scrollResponderHandleResponderRelease,
|
|
// $FlowFixMe
|
|
onResponderTerminate: this._scrollResponder
|
|
.scrollResponderHandleTerminate,
|
|
onResponderTerminationRequest: this._scrollResponder
|
|
.scrollResponderHandleTerminationRequest,
|
|
onScrollBeginDrag: this._scrollResponder
|
|
.scrollResponderHandleScrollBeginDrag,
|
|
onScrollEndDrag: this._scrollResponder.scrollResponderHandleScrollEndDrag,
|
|
onScrollShouldSetResponder: this._scrollResponder
|
|
.scrollResponderHandleScrollShouldSetResponder,
|
|
onStartShouldSetResponder: this._scrollResponder
|
|
.scrollResponderHandleStartShouldSetResponder,
|
|
onStartShouldSetResponderCapture: this._scrollResponder
|
|
.scrollResponderHandleStartShouldSetResponderCapture,
|
|
onTouchEnd: this._scrollResponder.scrollResponderHandleTouchEnd,
|
|
onTouchMove: this._scrollResponder.scrollResponderHandleTouchMove,
|
|
onTouchStart: this._scrollResponder.scrollResponderHandleTouchStart,
|
|
onTouchCancel: this._scrollResponder.scrollResponderHandleTouchCancel,
|
|
onScroll: this._handleScroll,
|
|
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 === true &&
|
|
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 === true ||
|
|
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 (
|
|
// $FlowFixMe
|
|
<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}
|
|
// $FlowFixMe
|
|
ref={this._setScrollViewRef}>
|
|
{contentContainer}
|
|
</ScrollViewClass>,
|
|
);
|
|
}
|
|
}
|
|
return (
|
|
// $FlowFixMe
|
|
<ScrollViewClass {...props} ref={this._setScrollViewRef}>
|
|
{contentContainer}
|
|
</ScrollViewClass>
|
|
);
|
|
}
|
|
}
|
|
|
|
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 = ScrollView;
|