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

875 lines
30 KiB
JavaScript

/**
* Copyright (c) 2013-present, Facebook, Inc.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @format
*/
'use strict';
const BoundingDimensions = require('BoundingDimensions');
const Platform = require('Platform');
const Position = require('Position');
const React = require('React');
const ReactNative = require('ReactNative');
const TVEventHandler = require('TVEventHandler');
const TouchEventUtils = require('fbjs/lib/TouchEventUtils');
const UIManager = require('UIManager');
const View = require('View');
const keyMirror = require('fbjs/lib/keyMirror');
const normalizeColor = require('normalizeColor');
/**
* `Touchable`: Taps done right.
*
* You hook your `ResponderEventPlugin` events into `Touchable`. `Touchable`
* will measure time/geometry and tells you when to give feedback to the user.
*
* ====================== Touchable Tutorial ===============================
* The `Touchable` mixin helps you handle the "press" interaction. It analyzes
* the geometry of elements, and observes when another responder (scroll view
* etc) has stolen the touch lock. It notifies your component when it should
* give feedback to the user. (bouncing/highlighting/unhighlighting).
*
* - When a touch was activated (typically you highlight)
* - When a touch was deactivated (typically you unhighlight)
* - When a touch was "pressed" - a touch ended while still within the geometry
* of the element, and no other element (like scroller) has "stolen" touch
* lock ("responder") (Typically you bounce the element).
*
* A good tap interaction isn't as simple as you might think. There should be a
* slight delay before showing a highlight when starting a touch. If a
* subsequent touch move exceeds the boundary of the element, it should
* unhighlight, but if that same touch is brought back within the boundary, it
* should rehighlight again. A touch can move in and out of that boundary
* several times, each time toggling highlighting, but a "press" is only
* triggered if that touch ends while within the element's boundary and no
* scroller (or anything else) has stolen the lock on touches.
*
* To create a new type of component that handles interaction using the
* `Touchable` mixin, do the following:
*
* - Initialize the `Touchable` state.
*
* getInitialState: function() {
* return merge(this.touchableGetInitialState(), yourComponentState);
* }
*
* - Choose the rendered component who's touches should start the interactive
* sequence. On that rendered node, forward all `Touchable` responder
* handlers. You can choose any rendered node you like. Choose a node whose
* hit target you'd like to instigate the interaction sequence:
*
* // In render function:
* return (
* <View
* onStartShouldSetResponder={this.touchableHandleStartShouldSetResponder}
* onResponderTerminationRequest={this.touchableHandleResponderTerminationRequest}
* onResponderGrant={this.touchableHandleResponderGrant}
* onResponderMove={this.touchableHandleResponderMove}
* onResponderRelease={this.touchableHandleResponderRelease}
* onResponderTerminate={this.touchableHandleResponderTerminate}>
* <View>
* Even though the hit detection/interactions are triggered by the
* wrapping (typically larger) node, we usually end up implementing
* custom logic that highlights this inner one.
* </View>
* </View>
* );
*
* - You may set up your own handlers for each of these events, so long as you
* also invoke the `touchable*` handlers inside of your custom handler.
*
* - Implement the handlers on your component class in order to provide
* feedback to the user. See documentation for each of these class methods
* that you should implement.
*
* touchableHandlePress: function() {
* this.performBounceAnimation(); // or whatever you want to do.
* },
* touchableHandleActivePressIn: function() {
* this.beginHighlighting(...); // Whatever you like to convey activation
* },
* touchableHandleActivePressOut: function() {
* this.endHighlighting(...); // Whatever you like to convey deactivation
* },
*
* - There are more advanced methods you can implement (see documentation below):
* touchableGetHighlightDelayMS: function() {
* return 20;
* }
* // In practice, *always* use a predeclared constant (conserve memory).
* touchableGetPressRectOffset: function() {
* return {top: 20, left: 20, right: 20, bottom: 100};
* }
*/
/**
* Touchable states.
*/
const States = keyMirror({
NOT_RESPONDER: null, // Not the responder
RESPONDER_INACTIVE_PRESS_IN: null, // Responder, inactive, in the `PressRect`
RESPONDER_INACTIVE_PRESS_OUT: null, // Responder, inactive, out of `PressRect`
RESPONDER_ACTIVE_PRESS_IN: null, // Responder, active, in the `PressRect`
RESPONDER_ACTIVE_PRESS_OUT: null, // Responder, active, out of `PressRect`
RESPONDER_ACTIVE_LONG_PRESS_IN: null, // Responder, active, in the `PressRect`, after long press threshold
RESPONDER_ACTIVE_LONG_PRESS_OUT: null, // Responder, active, out of `PressRect`, after long press threshold
ERROR: null,
});
/**
* Quick lookup map for states that are considered to be "active"
*/
const IsActive = {
RESPONDER_ACTIVE_PRESS_OUT: true,
RESPONDER_ACTIVE_PRESS_IN: true,
};
/**
* Quick lookup for states that are considered to be "pressing" and are
* therefore eligible to result in a "selection" if the press stops.
*/
const IsPressingIn = {
RESPONDER_INACTIVE_PRESS_IN: true,
RESPONDER_ACTIVE_PRESS_IN: true,
RESPONDER_ACTIVE_LONG_PRESS_IN: true,
};
const IsLongPressingIn = {
RESPONDER_ACTIVE_LONG_PRESS_IN: true,
};
/**
* Inputs to the state machine.
*/
const Signals = keyMirror({
DELAY: null,
RESPONDER_GRANT: null,
RESPONDER_RELEASE: null,
RESPONDER_TERMINATED: null,
ENTER_PRESS_RECT: null,
LEAVE_PRESS_RECT: null,
LONG_PRESS_DETECTED: null,
});
/**
* Mapping from States x Signals => States
*/
const Transitions = {
NOT_RESPONDER: {
DELAY: States.ERROR,
RESPONDER_GRANT: States.RESPONDER_INACTIVE_PRESS_IN,
RESPONDER_RELEASE: States.ERROR,
RESPONDER_TERMINATED: States.ERROR,
ENTER_PRESS_RECT: States.ERROR,
LEAVE_PRESS_RECT: States.ERROR,
LONG_PRESS_DETECTED: States.ERROR,
},
RESPONDER_INACTIVE_PRESS_IN: {
DELAY: States.RESPONDER_ACTIVE_PRESS_IN,
RESPONDER_GRANT: States.ERROR,
RESPONDER_RELEASE: States.NOT_RESPONDER,
RESPONDER_TERMINATED: States.NOT_RESPONDER,
ENTER_PRESS_RECT: States.RESPONDER_INACTIVE_PRESS_IN,
LEAVE_PRESS_RECT: States.RESPONDER_INACTIVE_PRESS_OUT,
LONG_PRESS_DETECTED: States.ERROR,
},
RESPONDER_INACTIVE_PRESS_OUT: {
DELAY: States.RESPONDER_ACTIVE_PRESS_OUT,
RESPONDER_GRANT: States.ERROR,
RESPONDER_RELEASE: States.NOT_RESPONDER,
RESPONDER_TERMINATED: States.NOT_RESPONDER,
ENTER_PRESS_RECT: States.RESPONDER_INACTIVE_PRESS_IN,
LEAVE_PRESS_RECT: States.RESPONDER_INACTIVE_PRESS_OUT,
LONG_PRESS_DETECTED: States.ERROR,
},
RESPONDER_ACTIVE_PRESS_IN: {
DELAY: States.ERROR,
RESPONDER_GRANT: States.ERROR,
RESPONDER_RELEASE: States.NOT_RESPONDER,
RESPONDER_TERMINATED: States.NOT_RESPONDER,
ENTER_PRESS_RECT: States.RESPONDER_ACTIVE_PRESS_IN,
LEAVE_PRESS_RECT: States.RESPONDER_ACTIVE_PRESS_OUT,
LONG_PRESS_DETECTED: States.RESPONDER_ACTIVE_LONG_PRESS_IN,
},
RESPONDER_ACTIVE_PRESS_OUT: {
DELAY: States.ERROR,
RESPONDER_GRANT: States.ERROR,
RESPONDER_RELEASE: States.NOT_RESPONDER,
RESPONDER_TERMINATED: States.NOT_RESPONDER,
ENTER_PRESS_RECT: States.RESPONDER_ACTIVE_PRESS_IN,
LEAVE_PRESS_RECT: States.RESPONDER_ACTIVE_PRESS_OUT,
LONG_PRESS_DETECTED: States.ERROR,
},
RESPONDER_ACTIVE_LONG_PRESS_IN: {
DELAY: States.ERROR,
RESPONDER_GRANT: States.ERROR,
RESPONDER_RELEASE: States.NOT_RESPONDER,
RESPONDER_TERMINATED: States.NOT_RESPONDER,
ENTER_PRESS_RECT: States.RESPONDER_ACTIVE_LONG_PRESS_IN,
LEAVE_PRESS_RECT: States.RESPONDER_ACTIVE_LONG_PRESS_OUT,
LONG_PRESS_DETECTED: States.RESPONDER_ACTIVE_LONG_PRESS_IN,
},
RESPONDER_ACTIVE_LONG_PRESS_OUT: {
DELAY: States.ERROR,
RESPONDER_GRANT: States.ERROR,
RESPONDER_RELEASE: States.NOT_RESPONDER,
RESPONDER_TERMINATED: States.NOT_RESPONDER,
ENTER_PRESS_RECT: States.RESPONDER_ACTIVE_LONG_PRESS_IN,
LEAVE_PRESS_RECT: States.RESPONDER_ACTIVE_LONG_PRESS_OUT,
LONG_PRESS_DETECTED: States.ERROR,
},
error: {
DELAY: States.NOT_RESPONDER,
RESPONDER_GRANT: States.RESPONDER_INACTIVE_PRESS_IN,
RESPONDER_RELEASE: States.NOT_RESPONDER,
RESPONDER_TERMINATED: States.NOT_RESPONDER,
ENTER_PRESS_RECT: States.NOT_RESPONDER,
LEAVE_PRESS_RECT: States.NOT_RESPONDER,
LONG_PRESS_DETECTED: States.NOT_RESPONDER,
},
};
// ==== Typical Constants for integrating into UI components ====
// var HIT_EXPAND_PX = 20;
// var HIT_VERT_OFFSET_PX = 10;
const HIGHLIGHT_DELAY_MS = 130;
const PRESS_EXPAND_PX = 20;
const LONG_PRESS_THRESHOLD = 500;
const LONG_PRESS_DELAY_MS = LONG_PRESS_THRESHOLD - HIGHLIGHT_DELAY_MS;
const LONG_PRESS_ALLOWED_MOVEMENT = 10;
// Default amount "active" region protrudes beyond box
/**
* By convention, methods prefixed with underscores are meant to be @private,
* and not @protected. Mixers shouldn't access them - not even to provide them
* as callback handlers.
*
*
* ========== Geometry =========
* `Touchable` only assumes that there exists a `HitRect` node. The `PressRect`
* is an abstract box that is extended beyond the `HitRect`.
*
* +--------------------------+
* | | - "Start" events in `HitRect` cause `HitRect`
* | +--------------------+ | to become the responder.
* | | +--------------+ | | - `HitRect` is typically expanded around
* | | | | | | the `VisualRect`, but shifted downward.
* | | | VisualRect | | | - After pressing down, after some delay,
* | | | | | | and before letting up, the Visual React
* | | +--------------+ | | will become "active". This makes it eligible
* | | HitRect | | for being highlighted (so long as the
* | +--------------------+ | press remains in the `PressRect`).
* | PressRect o |
* +----------------------|---+
* Out Region |
* +-----+ This gap between the `HitRect` and
* `PressRect` allows a touch to move far away
* from the original hit rect, and remain
* highlighted, and eligible for a "Press".
* Customize this via
* `touchableGetPressRectOffset()`.
*
*
*
* ======= State Machine =======
*
* +-------------+ <---+ RESPONDER_RELEASE
* |NOT_RESPONDER|
* +-------------+ <---+ RESPONDER_TERMINATED
* +
* | RESPONDER_GRANT (HitRect)
* v
* +---------------------------+ DELAY +-------------------------+ T + DELAY +------------------------------+
* |RESPONDER_INACTIVE_PRESS_IN|+-------->|RESPONDER_ACTIVE_PRESS_IN| +------------> |RESPONDER_ACTIVE_LONG_PRESS_IN|
* +---------------------------+ +-------------------------+ +------------------------------+
* + ^ + ^ + ^
* |LEAVE_ |ENTER_ |LEAVE_ |ENTER_ |LEAVE_ |ENTER_
* |PRESS_RECT |PRESS_RECT |PRESS_RECT |PRESS_RECT |PRESS_RECT |PRESS_RECT
* | | | | | |
* v + v + v +
* +----------------------------+ DELAY +--------------------------+ +-------------------------------+
* |RESPONDER_INACTIVE_PRESS_OUT|+------->|RESPONDER_ACTIVE_PRESS_OUT| |RESPONDER_ACTIVE_LONG_PRESS_OUT|
* +----------------------------+ +--------------------------+ +-------------------------------+
*
* T + DELAY => LONG_PRESS_DELAY_MS + DELAY
*
* Not drawn are the side effects of each transition. The most important side
* effect is the `touchableHandlePress` abstract method invocation that occurs
* when a responder is released while in either of the "Press" states.
*
* The other important side effects are the highlight abstract method
* invocations (internal callbacks) to be implemented by the mixer.
*
*
* @lends Touchable.prototype
*/
const TouchableMixin = {
componentDidMount: function() {
if (!Platform.isTV) {
return;
}
this._tvEventHandler = new TVEventHandler();
this._tvEventHandler.enable(this, function(cmp, evt) {
const myTag = ReactNative.findNodeHandle(cmp);
evt.dispatchConfig = {};
if (myTag === evt.tag) {
if (evt.eventType === 'focus') {
cmp.touchableHandleFocus(evt);
} else if (evt.eventType === 'blur') {
cmp.touchableHandleBlur(evt);
} else if (evt.eventType === 'select') {
cmp.touchableHandlePress &&
!cmp.props.disabled &&
cmp.touchableHandlePress(evt);
}
}
});
},
/**
* Clear all timeouts on unmount
*/
componentWillUnmount: function() {
if (this._tvEventHandler) {
this._tvEventHandler.disable();
delete this._tvEventHandler;
}
this.touchableDelayTimeout && clearTimeout(this.touchableDelayTimeout);
this.longPressDelayTimeout && clearTimeout(this.longPressDelayTimeout);
this.pressOutDelayTimeout && clearTimeout(this.pressOutDelayTimeout);
},
/**
* It's prefer that mixins determine state in this way, having the class
* explicitly mix the state in the one and only `getInitialState` method.
*
* @return {object} State object to be placed inside of
* `this.state.touchable`.
*/
touchableGetInitialState: function() {
return {
touchable: {touchState: undefined, responderID: null},
};
},
// ==== Hooks to Gesture Responder system ====
/**
* Must return true if embedded in a native platform scroll view.
*/
touchableHandleResponderTerminationRequest: function() {
return !this.props.rejectResponderTermination;
},
/**
* Must return true to start the process of `Touchable`.
*/
touchableHandleStartShouldSetResponder: function() {
return !this.props.disabled;
},
/**
* Return true to cancel press on long press.
*/
touchableLongPressCancelsPress: function() {
return true;
},
/**
* Place as callback for a DOM element's `onResponderGrant` event.
* @param {SyntheticEvent} e Synthetic event from event system.
*
*/
touchableHandleResponderGrant: function(e) {
const dispatchID = e.currentTarget;
// Since e is used in a callback invoked on another event loop
// (as in setTimeout etc), we need to call e.persist() on the
// event to make sure it doesn't get reused in the event object pool.
e.persist();
this.pressOutDelayTimeout && clearTimeout(this.pressOutDelayTimeout);
this.pressOutDelayTimeout = null;
this.state.touchable.touchState = States.NOT_RESPONDER;
this.state.touchable.responderID = dispatchID;
this._receiveSignal(Signals.RESPONDER_GRANT, e);
let delayMS =
this.touchableGetHighlightDelayMS !== undefined
? Math.max(this.touchableGetHighlightDelayMS(), 0)
: HIGHLIGHT_DELAY_MS;
delayMS = isNaN(delayMS) ? HIGHLIGHT_DELAY_MS : delayMS;
if (delayMS !== 0) {
this.touchableDelayTimeout = setTimeout(
this._handleDelay.bind(this, e),
delayMS,
);
} else {
this._handleDelay(e);
}
let longDelayMS =
this.touchableGetLongPressDelayMS !== undefined
? Math.max(this.touchableGetLongPressDelayMS(), 10)
: LONG_PRESS_DELAY_MS;
longDelayMS = isNaN(longDelayMS) ? LONG_PRESS_DELAY_MS : longDelayMS;
this.longPressDelayTimeout = setTimeout(
this._handleLongDelay.bind(this, e),
longDelayMS + delayMS,
);
},
/**
* Place as callback for a DOM element's `onResponderRelease` event.
*/
touchableHandleResponderRelease: function(e) {
this._receiveSignal(Signals.RESPONDER_RELEASE, e);
},
/**
* Place as callback for a DOM element's `onResponderTerminate` event.
*/
touchableHandleResponderTerminate: function(e) {
this._receiveSignal(Signals.RESPONDER_TERMINATED, e);
},
/**
* Place as callback for a DOM element's `onResponderMove` event.
*/
touchableHandleResponderMove: function(e) {
// Not enough time elapsed yet, wait for highlight -
// this is just a perf optimization.
if (
this.state.touchable.touchState === States.RESPONDER_INACTIVE_PRESS_IN
) {
return;
}
// Measurement may not have returned yet.
if (!this.state.touchable.positionOnActivate) {
return;
}
const positionOnActivate = this.state.touchable.positionOnActivate;
const dimensionsOnActivate = this.state.touchable.dimensionsOnActivate;
const pressRectOffset = this.touchableGetPressRectOffset
? this.touchableGetPressRectOffset()
: {
left: PRESS_EXPAND_PX,
right: PRESS_EXPAND_PX,
top: PRESS_EXPAND_PX,
bottom: PRESS_EXPAND_PX,
};
let pressExpandLeft = pressRectOffset.left;
let pressExpandTop = pressRectOffset.top;
let pressExpandRight = pressRectOffset.right;
let pressExpandBottom = pressRectOffset.bottom;
const hitSlop = this.touchableGetHitSlop
? this.touchableGetHitSlop()
: null;
if (hitSlop) {
pressExpandLeft += hitSlop.left;
pressExpandTop += hitSlop.top;
pressExpandRight += hitSlop.right;
pressExpandBottom += hitSlop.bottom;
}
const touch = TouchEventUtils.extractSingleTouch(e.nativeEvent);
const pageX = touch && touch.pageX;
const pageY = touch && touch.pageY;
if (this.pressInLocation) {
const movedDistance = this._getDistanceBetweenPoints(
pageX,
pageY,
this.pressInLocation.pageX,
this.pressInLocation.pageY,
);
if (movedDistance > LONG_PRESS_ALLOWED_MOVEMENT) {
this._cancelLongPressDelayTimeout();
}
}
const isTouchWithinActive =
pageX > positionOnActivate.left - pressExpandLeft &&
pageY > positionOnActivate.top - pressExpandTop &&
pageX <
positionOnActivate.left +
dimensionsOnActivate.width +
pressExpandRight &&
pageY <
positionOnActivate.top +
dimensionsOnActivate.height +
pressExpandBottom;
if (isTouchWithinActive) {
this._receiveSignal(Signals.ENTER_PRESS_RECT, e);
const curState = this.state.touchable.touchState;
if (curState === States.RESPONDER_INACTIVE_PRESS_IN) {
// fix for t7967420
this._cancelLongPressDelayTimeout();
}
} else {
this._cancelLongPressDelayTimeout();
this._receiveSignal(Signals.LEAVE_PRESS_RECT, e);
}
},
/**
* Invoked when the item receives focus. Mixers might override this to
* visually distinguish the `VisualRect` so that the user knows that it
* currently has the focus. Most platforms only support a single element being
* focused at a time, in which case there may have been a previously focused
* element that was blurred just prior to this.
*/
touchableHandleFocus: function(e: Event) {
this.props.onFocus && this.props.onFocus(e);
},
/**
* Invoked when the item loses focus. Mixers might override this to
* visually distinguish the `VisualRect` so that the user knows that it
* no longer has focus. Most platforms only support a single element being
* focused at a time, in which case the focus may have moved to another.
*/
touchableHandleBlur: function(e: Event) {
this.props.onBlur && this.props.onBlur(e);
},
// ==== Abstract Application Callbacks ====
/**
* Invoked when the item should be highlighted. Mixers should implement this
* to visually distinguish the `VisualRect` so that the user knows that
* releasing a touch will result in a "selection" (analog to click).
*
* @abstract
* touchableHandleActivePressIn: function,
*/
/**
* Invoked when the item is "active" (in that it is still eligible to become
* a "select") but the touch has left the `PressRect`. Usually the mixer will
* want to unhighlight the `VisualRect`. If the user (while pressing) moves
* back into the `PressRect` `touchableHandleActivePressIn` will be invoked
* again and the mixer should probably highlight the `VisualRect` again. This
* event will not fire on an `touchEnd/mouseUp` event, only move events while
* the user is depressing the mouse/touch.
*
* @abstract
* touchableHandleActivePressOut: function
*/
/**
* Invoked when the item is "selected" - meaning the interaction ended by
* letting up while the item was either in the state
* `RESPONDER_ACTIVE_PRESS_IN` or `RESPONDER_INACTIVE_PRESS_IN`.
*
* @abstract
* touchableHandlePress: function
*/
/**
* Invoked when the item is long pressed - meaning the interaction ended by
* letting up while the item was in `RESPONDER_ACTIVE_LONG_PRESS_IN`. If
* `touchableHandleLongPress` is *not* provided, `touchableHandlePress` will
* be called as it normally is. If `touchableHandleLongPress` is provided, by
* default any `touchableHandlePress` callback will not be invoked. To
* override this default behavior, override `touchableLongPressCancelsPress`
* to return false. As a result, `touchableHandlePress` will be called when
* lifting up, even if `touchableHandleLongPress` has also been called.
*
* @abstract
* touchableHandleLongPress: function
*/
/**
* Returns the number of millis to wait before triggering a highlight.
*
* @abstract
* touchableGetHighlightDelayMS: function
*/
/**
* Returns the amount to extend the `HitRect` into the `PressRect`. Positive
* numbers mean the size expands outwards.
*
* @abstract
* touchableGetPressRectOffset: function
*/
// ==== Internal Logic ====
/**
* Measures the `HitRect` node on activation. The Bounding rectangle is with
* respect to viewport - not page, so adding the `pageXOffset/pageYOffset`
* should result in points that are in the same coordinate system as an
* event's `globalX/globalY` data values.
*
* - Consider caching this for the lifetime of the component, or possibly
* being able to share this cache between any `ScrollMap` view.
*
* @sideeffects
* @private
*/
_remeasureMetricsOnActivation: function() {
const tag = this.state.touchable.responderID;
if (tag == null) {
return;
}
UIManager.measure(tag, this._handleQueryLayout);
},
_handleQueryLayout: function(l, t, w, h, globalX, globalY) {
//don't do anything UIManager failed to measure node
if (!l && !t && !w && !h && !globalX && !globalY) {
return;
}
this.state.touchable.positionOnActivate &&
Position.release(this.state.touchable.positionOnActivate);
this.state.touchable.dimensionsOnActivate &&
BoundingDimensions.release(this.state.touchable.dimensionsOnActivate);
this.state.touchable.positionOnActivate = Position.getPooled(
globalX,
globalY,
);
this.state.touchable.dimensionsOnActivate = BoundingDimensions.getPooled(
w,
h,
);
},
_handleDelay: function(e) {
this.touchableDelayTimeout = null;
this._receiveSignal(Signals.DELAY, e);
},
_handleLongDelay: function(e) {
this.longPressDelayTimeout = null;
const curState = this.state.touchable.touchState;
if (
curState !== States.RESPONDER_ACTIVE_PRESS_IN &&
curState !== States.RESPONDER_ACTIVE_LONG_PRESS_IN
) {
console.error(
'Attempted to transition from state `' +
curState +
'` to `' +
States.RESPONDER_ACTIVE_LONG_PRESS_IN +
'`, which is not supported. This is ' +
'most likely due to `Touchable.longPressDelayTimeout` not being cancelled.',
);
} else {
this._receiveSignal(Signals.LONG_PRESS_DETECTED, e);
}
},
/**
* Receives a state machine signal, performs side effects of the transition
* and stores the new state. Validates the transition as well.
*
* @param {Signals} signal State machine signal.
* @throws Error if invalid state transition or unrecognized signal.
* @sideeffects
*/
_receiveSignal: function(signal, e) {
const responderID = this.state.touchable.responderID;
const curState = this.state.touchable.touchState;
const nextState = Transitions[curState] && Transitions[curState][signal];
if (!responderID && signal === Signals.RESPONDER_RELEASE) {
return;
}
if (!nextState) {
throw new Error(
'Unrecognized signal `' +
signal +
'` or state `' +
curState +
'` for Touchable responder `' +
responderID +
'`',
);
}
if (nextState === States.ERROR) {
throw new Error(
'Touchable cannot transition from `' +
curState +
'` to `' +
signal +
'` for responder `' +
responderID +
'`',
);
}
if (curState !== nextState) {
this._performSideEffectsForTransition(curState, nextState, signal, e);
this.state.touchable.touchState = nextState;
}
},
_cancelLongPressDelayTimeout: function() {
this.longPressDelayTimeout && clearTimeout(this.longPressDelayTimeout);
this.longPressDelayTimeout = null;
},
_isHighlight: function(state) {
return (
state === States.RESPONDER_ACTIVE_PRESS_IN ||
state === States.RESPONDER_ACTIVE_LONG_PRESS_IN
);
},
_savePressInLocation: function(e) {
const touch = TouchEventUtils.extractSingleTouch(e.nativeEvent);
const pageX = touch && touch.pageX;
const pageY = touch && touch.pageY;
const locationX = touch && touch.locationX;
const locationY = touch && touch.locationY;
this.pressInLocation = {pageX, pageY, locationX, locationY};
},
_getDistanceBetweenPoints: function(aX, aY, bX, bY) {
const deltaX = aX - bX;
const deltaY = aY - bY;
return Math.sqrt(deltaX * deltaX + deltaY * deltaY);
},
/**
* Will perform a transition between touchable states, and identify any
* highlighting or unhighlighting that must be performed for this particular
* transition.
*
* @param {States} curState Current Touchable state.
* @param {States} nextState Next Touchable state.
* @param {Signal} signal Signal that triggered the transition.
* @param {Event} e Native event.
* @sideeffects
*/
_performSideEffectsForTransition: function(curState, nextState, signal, e) {
const curIsHighlight = this._isHighlight(curState);
const newIsHighlight = this._isHighlight(nextState);
const isFinalSignal =
signal === Signals.RESPONDER_TERMINATED ||
signal === Signals.RESPONDER_RELEASE;
if (isFinalSignal) {
this._cancelLongPressDelayTimeout();
}
if (!IsActive[curState] && IsActive[nextState]) {
this._remeasureMetricsOnActivation();
}
if (IsPressingIn[curState] && signal === Signals.LONG_PRESS_DETECTED) {
this.touchableHandleLongPress && this.touchableHandleLongPress(e);
}
if (newIsHighlight && !curIsHighlight) {
this._startHighlight(e);
} else if (!newIsHighlight && curIsHighlight) {
this._endHighlight(e);
}
if (IsPressingIn[curState] && signal === Signals.RESPONDER_RELEASE) {
const hasLongPressHandler = !!this.props.onLongPress;
const pressIsLongButStillCallOnPress =
IsLongPressingIn[curState] && // We *are* long pressing.. // But either has no long handler
(!hasLongPressHandler || !this.touchableLongPressCancelsPress()); // or we're told to ignore it.
const shouldInvokePress =
!IsLongPressingIn[curState] || pressIsLongButStillCallOnPress;
if (shouldInvokePress && this.touchableHandlePress) {
if (!newIsHighlight && !curIsHighlight) {
// we never highlighted because of delay, but we should highlight now
this._startHighlight(e);
this._endHighlight(e);
}
if (Platform.OS === 'android') {
this._playTouchSound();
}
this.touchableHandlePress(e);
}
}
this.touchableDelayTimeout && clearTimeout(this.touchableDelayTimeout);
this.touchableDelayTimeout = null;
},
_playTouchSound: function() {
UIManager.playTouchSound();
},
_startHighlight: function(e) {
this._savePressInLocation(e);
this.touchableHandleActivePressIn && this.touchableHandleActivePressIn(e);
},
_endHighlight: function(e) {
if (this.touchableHandleActivePressOut) {
if (
this.touchableGetPressOutDelayMS &&
this.touchableGetPressOutDelayMS()
) {
this.pressOutDelayTimeout = setTimeout(() => {
this.touchableHandleActivePressOut(e);
}, this.touchableGetPressOutDelayMS());
} else {
this.touchableHandleActivePressOut(e);
}
}
},
};
const Touchable = {
Mixin: TouchableMixin,
TOUCH_TARGET_DEBUG: false, // Highlights all touchable targets. Toggle with Inspector.
/**
* Renders a debugging overlay to visualize touch target with hitSlop (might not work on Android).
*/
renderDebugView: ({color, hitSlop}) => {
if (!Touchable.TOUCH_TARGET_DEBUG) {
return null;
}
if (!__DEV__) {
throw Error(
'Touchable.TOUCH_TARGET_DEBUG should not be enabled in prod!',
);
}
const debugHitSlopStyle = {};
hitSlop = hitSlop || {top: 0, bottom: 0, left: 0, right: 0};
for (const key in hitSlop) {
debugHitSlopStyle[key] = -hitSlop[key];
}
const hexColor =
'#' + ('00000000' + normalizeColor(color).toString(16)).substr(-8);
return (
<View
pointerEvents="none"
style={{
position: 'absolute',
borderColor: hexColor.slice(0, -2) + '55', // More opaque
borderWidth: 1,
borderStyle: 'dashed',
backgroundColor: hexColor.slice(0, -2) + '0F', // Less opaque
...debugHitSlopStyle,
}}
/>
);
},
};
module.exports = Touchable;