"use strict"; exports.__esModule = true; exports.default = void 0; var _Dimensions = _interopRequireDefault(require("../../exports/Dimensions")); var _findNodeHandle = _interopRequireDefault(require("../../exports/findNodeHandle")); var _invariant = _interopRequireDefault(require("fbjs/lib/invariant")); var _Platform = _interopRequireDefault(require("../../exports/Platform")); var _TextInputState = _interopRequireDefault(require("../TextInputState")); var _UIManager = _interopRequireDefault(require("../../exports/UIManager")); var _warning = _interopRequireDefault(require("fbjs/lib/warning")); function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; } /** * Copyright (c) Nicolas Gallagher. * 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. * * */ /** * Mixin that can be integrated in order to handle scrolling that plays well * with `ResponderEventPlugin`. Integrate with your platform specific scroll * views, or even your custom built (every-frame animating) scroll views so that * all of these systems play well with the `ResponderEventPlugin`. * * iOS scroll event timing nuances: * =============================== * * * Scrolling without bouncing, if you touch down: * ------------------------------- * * 1. `onMomentumScrollBegin` (when animation begins after letting up) * ... physical touch starts ... * 2. `onTouchStartCapture` (when you press down to stop the scroll) * 3. `onTouchStart` (same, but bubble phase) * 4. `onResponderRelease` (when lifting up - you could pause forever before * lifting) * 5. `onMomentumScrollEnd` * * * Scrolling with bouncing, if you touch down: * ------------------------------- * * 1. `onMomentumScrollBegin` (when animation begins after letting up) * ... bounce begins ... * ... some time elapses ... * ... physical touch during bounce ... * 2. `onMomentumScrollEnd` (Makes no sense why this occurs first during bounce) * 3. `onTouchStartCapture` (immediately after `onMomentumScrollEnd`) * 4. `onTouchStart` (same, but bubble phase) * 5. `onTouchEnd` (You could hold the touch start for a long time) * 6. `onMomentumScrollBegin` (When releasing the view starts bouncing back) * * So when we receive an `onTouchStart`, how can we tell if we are touching * *during* an animation (which then causes the animation to stop)? The only way * to tell is if the `touchStart` occurred immediately after the * `onMomentumScrollEnd`. * * This is abstracted out for you, so you can just call this.scrollResponderIsAnimating() if * necessary * * `ScrollResponder` also includes logic for blurring a currently focused input * if one is focused while scrolling. The `ScrollResponder` is a natural place * to put this logic since it can support not dismissing the keyboard while * scrolling, unless a recognized "tap"-like gesture has occurred. * * The public lifecycle API includes events for keyboard interaction, responder * interaction, and scrolling (among others). The keyboard callbacks * `onKeyboardWill/Did/*` are *global* events, but are invoked on scroll * responder's props so that you can guarantee that the scroll responder's * internal state has been updated accordingly (and deterministically) by * the time the props callbacks are invoke. Otherwise, you would always wonder * if the scroll responder is currently in a state where it recognizes new * keyboard positions etc. If coordinating scrolling with keyboard movement, * *always* use these hooks instead of listening to your own global keyboard * events. * * Public keyboard lifecycle API: (props callbacks) * * Standard Keyboard Appearance Sequence: * * this.props.onKeyboardWillShow * this.props.onKeyboardDidShow * * `onScrollResponderKeyboardDismissed` will be invoked if an appropriate * tap inside the scroll responder's scrollable region was responsible * for the dismissal of the keyboard. There are other reasons why the * keyboard could be dismissed. * * this.props.onScrollResponderKeyboardDismissed * * Standard Keyboard Hide Sequence: * * this.props.onKeyboardWillHide * this.props.onKeyboardDidHide */ var emptyObject = {}; var IS_ANIMATING_TOUCH_START_THRESHOLD_MS = 16; var ScrollResponderMixin = { // mixins: [Subscribable.Mixin], scrollResponderMixinGetInitialState: function scrollResponderMixinGetInitialState() { return { isTouching: false, lastMomentumScrollBeginTime: 0, lastMomentumScrollEndTime: 0, // Reset to false every time becomes responder. This is used to: // - Determine if the scroll view has been scrolled and therefore should // refuse to give up its responder lock. // - Determine if releasing should dismiss the keyboard when we are in // tap-to-dismiss mode (!this.props.keyboardShouldPersistTaps). observedScrollSinceBecomingResponder: false, becameResponderWhileAnimating: false }; }, /** * Invoke this from an `onScroll` event. */ scrollResponderHandleScrollShouldSetResponder: function scrollResponderHandleScrollShouldSetResponder() { return this.state.isTouching; }, /** * Merely touch starting is not sufficient for a scroll view to become the * responder. Being the "responder" means that the very next touch move/end * event will result in an action/movement. * * Invoke this from an `onStartShouldSetResponder` event. * * `onStartShouldSetResponder` is used when the next move/end will trigger * some UI movement/action, but when you want to yield priority to views * nested inside of the view. * * There may be some cases where scroll views actually should return `true` * from `onStartShouldSetResponder`: Any time we are detecting a standard tap * that gives priority to nested views. * * - If a single tap on the scroll view triggers an action such as * recentering a map style view yet wants to give priority to interaction * views inside (such as dropped pins or labels), then we would return true * from this method when there is a single touch. * * - Similar to the previous case, if a two finger "tap" should trigger a * zoom, we would check the `touches` count, and if `>= 2`, we would return * true. * */ scrollResponderHandleStartShouldSetResponder: function scrollResponderHandleStartShouldSetResponder() { return false; }, /** * There are times when the scroll view wants to become the responder * (meaning respond to the next immediate `touchStart/touchEnd`), in a way * that *doesn't* give priority to nested views (hence the capture phase): * * - Currently animating. * - Tapping anywhere that is not the focused input, while the keyboard is * up (which should dismiss the keyboard). * * Invoke this from an `onStartShouldSetResponderCapture` event. */ scrollResponderHandleStartShouldSetResponderCapture: function scrollResponderHandleStartShouldSetResponderCapture(e) { // First see if we want to eat taps while the keyboard is up // var currentlyFocusedTextInput = TextInputState.currentlyFocusedField(); // if (!this.props.keyboardShouldPersistTaps && // currentlyFocusedTextInput != null && // e.target !== currentlyFocusedTextInput) { // return true; // } return this.scrollResponderIsAnimating(); }, /** * Invoke this from an `onResponderReject` event. * * Some other element is not yielding its role as responder. Normally, we'd * just disable the `UIScrollView`, but a touch has already began on it, the * `UIScrollView` will not accept being disabled after that. The easiest * solution for now is to accept the limitation of disallowing this * altogether. To improve this, find a way to disable the `UIScrollView` after * a touch has already started. */ scrollResponderHandleResponderReject: function scrollResponderHandleResponderReject() { (0, _warning.default)(false, "ScrollView doesn't take rejection well - scrolls anyway"); }, /** * We will allow the scroll view to give up its lock iff it acquired the lock * during an animation. This is a very useful default that happens to satisfy * many common user experiences. * * - Stop a scroll on the left edge, then turn that into an outer view's * backswipe. * - Stop a scroll mid-bounce at the top, continue pulling to have the outer * view dismiss. * - However, without catching the scroll view mid-bounce (while it is * motionless), if you drag far enough for the scroll view to become * responder (and therefore drag the scroll view a bit), any backswipe * navigation of a swipe gesture higher in the view hierarchy, should be * rejected. */ scrollResponderHandleTerminationRequest: function scrollResponderHandleTerminationRequest() { return !this.state.observedScrollSinceBecomingResponder; }, /** * Invoke this from an `onTouchEnd` event. * * @param {SyntheticEvent} e Event. */ scrollResponderHandleTouchEnd: function scrollResponderHandleTouchEnd(e) { var nativeEvent = e.nativeEvent; this.state.isTouching = nativeEvent.touches.length !== 0; this.props.onTouchEnd && this.props.onTouchEnd(e); }, /** * Invoke this from an `onResponderRelease` event. */ scrollResponderHandleResponderRelease: function scrollResponderHandleResponderRelease(e) { this.props.onResponderRelease && this.props.onResponderRelease(e); // By default scroll views will unfocus a textField // if another touch occurs outside of it var currentlyFocusedTextInput = _TextInputState.default.currentlyFocusedField(); if (!this.props.keyboardShouldPersistTaps && currentlyFocusedTextInput != null && e.target !== currentlyFocusedTextInput && !this.state.observedScrollSinceBecomingResponder && !this.state.becameResponderWhileAnimating) { this.props.onScrollResponderKeyboardDismissed && this.props.onScrollResponderKeyboardDismissed(e); _TextInputState.default.blurTextInput(currentlyFocusedTextInput); } }, scrollResponderHandleScroll: function scrollResponderHandleScroll(e) { this.state.observedScrollSinceBecomingResponder = true; this.props.onScroll && this.props.onScroll(e); }, /** * Invoke this from an `onResponderGrant` event. */ scrollResponderHandleResponderGrant: function scrollResponderHandleResponderGrant(e) { this.state.observedScrollSinceBecomingResponder = false; this.props.onResponderGrant && this.props.onResponderGrant(e); this.state.becameResponderWhileAnimating = this.scrollResponderIsAnimating(); }, /** * Unfortunately, `onScrollBeginDrag` also fires when *stopping* the scroll * animation, and there's not an easy way to distinguish a drag vs. stopping * momentum. * * Invoke this from an `onScrollBeginDrag` event. */ scrollResponderHandleScrollBeginDrag: function scrollResponderHandleScrollBeginDrag(e) { this.props.onScrollBeginDrag && this.props.onScrollBeginDrag(e); }, /** * Invoke this from an `onScrollEndDrag` event. */ scrollResponderHandleScrollEndDrag: function scrollResponderHandleScrollEndDrag(e) { this.props.onScrollEndDrag && this.props.onScrollEndDrag(e); }, /** * Invoke this from an `onMomentumScrollBegin` event. */ scrollResponderHandleMomentumScrollBegin: function scrollResponderHandleMomentumScrollBegin(e) { this.state.lastMomentumScrollBeginTime = Date.now(); this.props.onMomentumScrollBegin && this.props.onMomentumScrollBegin(e); }, /** * Invoke this from an `onMomentumScrollEnd` event. */ scrollResponderHandleMomentumScrollEnd: function scrollResponderHandleMomentumScrollEnd(e) { this.state.lastMomentumScrollEndTime = Date.now(); this.props.onMomentumScrollEnd && this.props.onMomentumScrollEnd(e); }, /** * Invoke this from an `onTouchStart` event. * * Since we know that the `SimpleEventPlugin` occurs later in the plugin * order, after `ResponderEventPlugin`, we can detect that we were *not* * permitted to be the responder (presumably because a contained view became * responder). The `onResponderReject` won't fire in that case - it only * fires when a *current* responder rejects our request. * * @param {SyntheticEvent} e Touch Start event. */ scrollResponderHandleTouchStart: function scrollResponderHandleTouchStart(e) { this.state.isTouching = true; this.props.onTouchStart && this.props.onTouchStart(e); }, /** * Invoke this from an `onTouchMove` event. * * Since we know that the `SimpleEventPlugin` occurs later in the plugin * order, after `ResponderEventPlugin`, we can detect that we were *not* * permitted to be the responder (presumably because a contained view became * responder). The `onResponderReject` won't fire in that case - it only * fires when a *current* responder rejects our request. * * @param {SyntheticEvent} e Touch Start event. */ scrollResponderHandleTouchMove: function scrollResponderHandleTouchMove(e) { this.props.onTouchMove && this.props.onTouchMove(e); }, /** * A helper function for this class that lets us quickly determine if the * view is currently animating. This is particularly useful to know when * a touch has just started or ended. */ scrollResponderIsAnimating: function scrollResponderIsAnimating() { var now = Date.now(); var timeSinceLastMomentumScrollEnd = now - this.state.lastMomentumScrollEndTime; var isAnimating = timeSinceLastMomentumScrollEnd < IS_ANIMATING_TOUCH_START_THRESHOLD_MS || this.state.lastMomentumScrollEndTime < this.state.lastMomentumScrollBeginTime; return isAnimating; }, /** * Returns the node that represents native view that can be scrolled. * Components can pass what node to use by defining a `getScrollableNode` * function otherwise `this` is used. */ scrollResponderGetScrollableNode: function scrollResponderGetScrollableNode() { return this.getScrollableNode ? this.getScrollableNode() : (0, _findNodeHandle.default)(this); }, /** * A helper function to scroll to a specific point in the scrollview. * This is currently used to help focus on child textviews, but can also * be used to quickly scroll to any element we want to focus. Syntax: * * scrollResponderScrollTo(options: {x: number = 0; y: number = 0; animated: boolean = true}) * * Note: The weird argument signature is due to the fact that, for historical reasons, * the function also accepts separate arguments as as alternative to the options object. * This is deprecated due to ambiguity (y before x), and SHOULD NOT BE USED. */ scrollResponderScrollTo: function scrollResponderScrollTo(x, y, animated) { if (typeof x === 'number') { console.warn('`scrollResponderScrollTo(x, y, animated)` is deprecated. Use `scrollResponderScrollTo({x: 5, y: 5, animated: true})` instead.'); } else { var _ref = x || emptyObject; x = _ref.x; y = _ref.y; animated = _ref.animated; } var node = this.scrollResponderGetScrollableNode(); var left = x || 0; var top = y || 0; if (typeof node.scroll === 'function') { node.scroll({ top: top, left: left, behavior: !animated ? 'auto' : 'smooth' }); } else { node.scrollLeft = left; node.scrollTop = top; } }, /** * A helper function to zoom to a specific rect in the scrollview. The argument has the shape * {x: number; y: number; width: number; height: number; animated: boolean = true} * * @platform ios */ scrollResponderZoomTo: function scrollResponderZoomTo(rect, animated) // deprecated, put this inside the rect argument instead { if (_Platform.default.OS !== 'ios') { (0, _invariant.default)('zoomToRect is not implemented'); } }, /** * Displays the scroll indicators momentarily. */ scrollResponderFlashScrollIndicators: function scrollResponderFlashScrollIndicators() {}, /** * This method should be used as the callback to onFocus in a TextInputs' * parent view. Note that any module using this mixin needs to return * the parent view's ref in getScrollViewRef() in order to use this method. * @param {any} nodeHandle The TextInput node handle * @param {number} additionalOffset The scroll view's top "contentInset". * Default is 0. * @param {bool} preventNegativeScrolling Whether to allow pulling the content * down to make it meet the keyboard's top. Default is false. */ scrollResponderScrollNativeHandleToKeyboard: function scrollResponderScrollNativeHandleToKeyboard(nodeHandle, additionalOffset, preventNegativeScrollOffset) { this.additionalScrollOffset = additionalOffset || 0; this.preventNegativeScrollOffset = !!preventNegativeScrollOffset; _UIManager.default.measureLayout(nodeHandle, (0, _findNodeHandle.default)(this.getInnerViewNode()), this.scrollResponderTextInputFocusError, this.scrollResponderInputMeasureAndScrollToKeyboard); }, /** * The calculations performed here assume the scroll view takes up the entire * screen - even if has some content inset. We then measure the offsets of the * keyboard, and compensate both for the scroll view's "contentInset". * * @param {number} left Position of input w.r.t. table view. * @param {number} top Position of input w.r.t. table view. * @param {number} width Width of the text input. * @param {number} height Height of the text input. */ scrollResponderInputMeasureAndScrollToKeyboard: function scrollResponderInputMeasureAndScrollToKeyboard(left, top, width, height) { var keyboardScreenY = _Dimensions.default.get('window').height; if (this.keyboardWillOpenTo) { keyboardScreenY = this.keyboardWillOpenTo.endCoordinates.screenY; } var scrollOffsetY = top - keyboardScreenY + height + this.additionalScrollOffset; // By default, this can scroll with negative offset, pulling the content // down so that the target component's bottom meets the keyboard's top. // If requested otherwise, cap the offset at 0 minimum to avoid content // shifting down. if (this.preventNegativeScrollOffset) { scrollOffsetY = Math.max(0, scrollOffsetY); } this.scrollResponderScrollTo({ x: 0, y: scrollOffsetY, animated: true }); this.additionalOffset = 0; this.preventNegativeScrollOffset = false; }, scrollResponderTextInputFocusError: function scrollResponderTextInputFocusError(e) { console.error('Error measuring text field: ', e); }, /** * `componentWillMount` is the closest thing to a standard "constructor" for * React components. * * The `keyboardWillShow` is called before input focus. */ UNSAFE_componentWillMount: function UNSAFE_componentWillMount() { this.keyboardWillOpenTo = null; this.additionalScrollOffset = 0; // this.addListenerOn(RCTDeviceEventEmitter, 'keyboardWillShow', this.scrollResponderKeyboardWillShow); // this.addListenerOn(RCTDeviceEventEmitter, 'keyboardWillHide', this.scrollResponderKeyboardWillHide); // this.addListenerOn(RCTDeviceEventEmitter, 'keyboardDidShow', this.scrollResponderKeyboardDidShow); // this.addListenerOn(RCTDeviceEventEmitter, 'keyboardDidHide', this.scrollResponderKeyboardDidHide); }, /** * Warning, this may be called several times for a single keyboard opening. * It's best to store the information in this method and then take any action * at a later point (either in `keyboardDidShow` or other). * * Here's the order that events occur in: * - focus * - willShow {startCoordinates, endCoordinates} several times * - didShow several times * - blur * - willHide {startCoordinates, endCoordinates} several times * - didHide several times * * The `ScrollResponder` providesModule callbacks for each of these events. * Even though any user could have easily listened to keyboard events * themselves, using these `props` callbacks ensures that ordering of events * is consistent - and not dependent on the order that the keyboard events are * subscribed to. This matters when telling the scroll view to scroll to where * the keyboard is headed - the scroll responder better have been notified of * the keyboard destination before being instructed to scroll to where the * keyboard will be. Stick to the `ScrollResponder` callbacks, and everything * will work. * * WARNING: These callbacks will fire even if a keyboard is displayed in a * different navigation pane. Filter out the events to determine if they are * relevant to you. (For example, only if you receive these callbacks after * you had explicitly focused a node etc). */ scrollResponderKeyboardWillShow: function scrollResponderKeyboardWillShow(e) { this.keyboardWillOpenTo = e; this.props.onKeyboardWillShow && this.props.onKeyboardWillShow(e); }, scrollResponderKeyboardWillHide: function scrollResponderKeyboardWillHide(e) { this.keyboardWillOpenTo = null; this.props.onKeyboardWillHide && this.props.onKeyboardWillHide(e); }, scrollResponderKeyboardDidShow: function scrollResponderKeyboardDidShow(e) { // TODO(7693961): The event for DidShow is not available on iOS yet. // Use the one from WillShow and do not assign. if (e) { this.keyboardWillOpenTo = e; } this.props.onKeyboardDidShow && this.props.onKeyboardDidShow(e); }, scrollResponderKeyboardDidHide: function scrollResponderKeyboardDidHide(e) { this.keyboardWillOpenTo = null; this.props.onKeyboardDidHide && this.props.onKeyboardDidHide(e); } }; var ScrollResponder = { Mixin: ScrollResponderMixin }; var _default = ScrollResponder; exports.default = _default; module.exports = exports.default;