This app provides monitoring and information features for the common freifunk user and the technical stuff of a freifunk community.
Code base is taken from a TUM Practical Course project and added here to see if Freifunk Altdorf can use it.
https://www.freifunk-altdorf.de
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
413 lines
18 KiB
413 lines
18 KiB
/** |
|
* 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. |
|
* |
|
* @providesModule PanResponder |
|
*/ |
|
|
|
'use strict'; |
|
|
|
const InteractionManager = require('./InteractionManager'); |
|
const TouchHistoryMath = require('TouchHistoryMath'); |
|
|
|
const currentCentroidXOfTouchesChangedAfter = TouchHistoryMath.currentCentroidXOfTouchesChangedAfter; |
|
const currentCentroidYOfTouchesChangedAfter = TouchHistoryMath.currentCentroidYOfTouchesChangedAfter; |
|
const previousCentroidXOfTouchesChangedAfter = TouchHistoryMath.previousCentroidXOfTouchesChangedAfter; |
|
const previousCentroidYOfTouchesChangedAfter = TouchHistoryMath.previousCentroidYOfTouchesChangedAfter; |
|
const currentCentroidX = TouchHistoryMath.currentCentroidX; |
|
const currentCentroidY = TouchHistoryMath.currentCentroidY; |
|
|
|
/** |
|
* `PanResponder` reconciles several touches into a single gesture. It makes |
|
* single-touch gestures resilient to extra touches, and can be used to |
|
* recognize simple multi-touch gestures. |
|
* |
|
* By default, `PanResponder` holds an `InteractionManager` handle to block |
|
* long-running JS events from interrupting active gestures. |
|
* |
|
* It provides a predictable wrapper of the responder handlers provided by the |
|
* [gesture responder system](docs/gesture-responder-system.html). |
|
* For each handler, it provides a new `gestureState` object alongside the |
|
* native event object: |
|
* |
|
* ``` |
|
* onPanResponderMove: (event, gestureState) => {} |
|
* ``` |
|
* |
|
* A native event is a synthetic touch event with the following form: |
|
* |
|
* - `nativeEvent` |
|
* + `changedTouches` - Array of all touch events that have changed since the last event |
|
* + `identifier` - The ID of the touch |
|
* + `locationX` - The X position of the touch, relative to the element |
|
* + `locationY` - The Y position of the touch, relative to the element |
|
* + `pageX` - The X position of the touch, relative to the root element |
|
* + `pageY` - The Y position of the touch, relative to the root element |
|
* + `target` - The node id of the element receiving the touch event |
|
* + `timestamp` - A time identifier for the touch, useful for velocity calculation |
|
* + `touches` - Array of all current touches on the screen |
|
* |
|
* A `gestureState` object has the following: |
|
* |
|
* - `stateID` - ID of the gestureState- persisted as long as there at least |
|
* one touch on screen |
|
* - `moveX` - the latest screen coordinates of the recently-moved touch |
|
* - `moveY` - the latest screen coordinates of the recently-moved touch |
|
* - `x0` - the screen coordinates of the responder grant |
|
* - `y0` - the screen coordinates of the responder grant |
|
* - `dx` - accumulated distance of the gesture since the touch started |
|
* - `dy` - accumulated distance of the gesture since the touch started |
|
* - `vx` - current velocity of the gesture |
|
* - `vy` - current velocity of the gesture |
|
* - `numberActiveTouches` - Number of touches currently on screen |
|
* |
|
* ### Basic Usage |
|
* |
|
* ``` |
|
* componentWillMount: function() { |
|
* this._panResponder = PanResponder.create({ |
|
* // Ask to be the responder: |
|
* onStartShouldSetPanResponder: (evt, gestureState) => true, |
|
* onStartShouldSetPanResponderCapture: (evt, gestureState) => true, |
|
* onMoveShouldSetPanResponder: (evt, gestureState) => true, |
|
* onMoveShouldSetPanResponderCapture: (evt, gestureState) => true, |
|
* |
|
* onPanResponderGrant: (evt, gestureState) => { |
|
* // The gesture has started. Show visual feedback so the user knows |
|
* // what is happening! |
|
* |
|
* // gestureState.d{x,y} will be set to zero now |
|
* }, |
|
* onPanResponderMove: (evt, gestureState) => { |
|
* // The most recent move distance is gestureState.move{X,Y} |
|
* |
|
* // The accumulated gesture distance since becoming responder is |
|
* // gestureState.d{x,y} |
|
* }, |
|
* onPanResponderTerminationRequest: (evt, gestureState) => true, |
|
* onPanResponderRelease: (evt, gestureState) => { |
|
* // The user has released all touches while this view is the |
|
* // responder. This typically means a gesture has succeeded |
|
* }, |
|
* onPanResponderTerminate: (evt, gestureState) => { |
|
* // Another component has become the responder, so this gesture |
|
* // should be cancelled |
|
* }, |
|
* onShouldBlockNativeResponder: (evt, gestureState) => { |
|
* // Returns whether this component should block native components from becoming the JS |
|
* // responder. Returns true by default. Is currently only supported on android. |
|
* return true; |
|
* }, |
|
* }); |
|
* }, |
|
* |
|
* render: function() { |
|
* return ( |
|
* <View {...this._panResponder.panHandlers} /> |
|
* ); |
|
* }, |
|
* |
|
* ``` |
|
* |
|
* ### Working Example |
|
* |
|
* To see it in action, try the |
|
* [PanResponder example in RNTester](https://github.com/facebook/react-native/blob/master/RNTester/js/PanResponderExample.js) |
|
*/ |
|
|
|
const PanResponder = { |
|
|
|
/** |
|
* |
|
* A graphical explanation of the touch data flow: |
|
* |
|
* +----------------------------+ +--------------------------------+ |
|
* | ResponderTouchHistoryStore | |TouchHistoryMath | |
|
* +----------------------------+ +----------+---------------------+ |
|
* |Global store of touchHistory| |Allocation-less math util | |
|
* |including activeness, start | |on touch history (centroids | |
|
* |position, prev/cur position.| |and multitouch movement etc) | |
|
* | | | | |
|
* +----^-----------------------+ +----^---------------------------+ |
|
* | | |
|
* | (records relevant history | |
|
* | of touches relevant for | |
|
* | implementing higher level | |
|
* | gestures) | |
|
* | | |
|
* +----+-----------------------+ +----|---------------------------+ |
|
* | ResponderEventPlugin | | | Your App/Component | |
|
* +----------------------------+ +----|---------------------------+ |
|
* |Negotiates which view gets | Low level | | High level | |
|
* |onResponderMove events. | events w/ | +-+-------+ events w/ | |
|
* |Also records history into | touchHistory| | Pan | multitouch + | |
|
* |ResponderTouchHistoryStore. +---------------->Responder+-----> accumulative| |
|
* +----------------------------+ attached to | | | distance and | |
|
* each event | +---------+ velocity. | |
|
* | | |
|
* | | |
|
* +--------------------------------+ |
|
* |
|
* |
|
* |
|
* Gesture that calculates cumulative movement over time in a way that just |
|
* "does the right thing" for multiple touches. The "right thing" is very |
|
* nuanced. When moving two touches in opposite directions, the cumulative |
|
* distance is zero in each dimension. When two touches move in parallel five |
|
* pixels in the same direction, the cumulative distance is five, not ten. If |
|
* two touches start, one moves five in a direction, then stops and the other |
|
* touch moves fives in the same direction, the cumulative distance is ten. |
|
* |
|
* This logic requires a kind of processing of time "clusters" of touch events |
|
* so that two touch moves that essentially occur in parallel but move every |
|
* other frame respectively, are considered part of the same movement. |
|
* |
|
* Explanation of some of the non-obvious fields: |
|
* |
|
* - moveX/moveY: If no move event has been observed, then `(moveX, moveY)` is |
|
* invalid. If a move event has been observed, `(moveX, moveY)` is the |
|
* centroid of the most recently moved "cluster" of active touches. |
|
* (Currently all move have the same timeStamp, but later we should add some |
|
* threshold for what is considered to be "moving"). If a palm is |
|
* accidentally counted as a touch, but a finger is moving greatly, the palm |
|
* will move slightly, but we only want to count the single moving touch. |
|
* - x0/y0: Centroid location (non-cumulative) at the time of becoming |
|
* responder. |
|
* - dx/dy: Cumulative touch distance - not the same thing as sum of each touch |
|
* distance. Accounts for touch moves that are clustered together in time, |
|
* moving the same direction. Only valid when currently responder (otherwise, |
|
* it only represents the drag distance below the threshold). |
|
* - vx/vy: Velocity. |
|
*/ |
|
|
|
_initializeGestureState: function (gestureState) { |
|
gestureState.moveX = 0; |
|
gestureState.moveY = 0; |
|
gestureState.x0 = 0; |
|
gestureState.y0 = 0; |
|
gestureState.dx = 0; |
|
gestureState.dy = 0; |
|
gestureState.vx = 0; |
|
gestureState.vy = 0; |
|
gestureState.numberActiveTouches = 0; |
|
// All `gestureState` accounts for timeStamps up until: |
|
gestureState._accountsForMovesUpTo = 0; |
|
}, |
|
|
|
/** |
|
* This is nuanced and is necessary. It is incorrect to continuously take all |
|
* active *and* recently moved touches, find the centroid, and track how that |
|
* result changes over time. Instead, we must take all recently moved |
|
* touches, and calculate how the centroid has changed just for those |
|
* recently moved touches, and append that change to an accumulator. This is |
|
* to (at least) handle the case where the user is moving three fingers, and |
|
* then one of the fingers stops but the other two continue. |
|
* |
|
* This is very different than taking all of the recently moved touches and |
|
* storing their centroid as `dx/dy`. For correctness, we must *accumulate |
|
* changes* in the centroid of recently moved touches. |
|
* |
|
* There is also some nuance with how we handle multiple moved touches in a |
|
* single event. With the way `ReactNativeEventEmitter` dispatches touches as |
|
* individual events, multiple touches generate two 'move' events, each of |
|
* them triggering `onResponderMove`. But with the way `PanResponder` works, |
|
* all of the gesture inference is performed on the first dispatch, since it |
|
* looks at all of the touches (even the ones for which there hasn't been a |
|
* native dispatch yet). Therefore, `PanResponder` does not call |
|
* `onResponderMove` passed the first dispatch. This diverges from the |
|
* typical responder callback pattern (without using `PanResponder`), but |
|
* avoids more dispatches than necessary. |
|
*/ |
|
_updateGestureStateOnMove: function (gestureState, touchHistory) { |
|
gestureState.numberActiveTouches = touchHistory.numberActiveTouches; |
|
gestureState.moveX = currentCentroidXOfTouchesChangedAfter(touchHistory, gestureState._accountsForMovesUpTo); |
|
gestureState.moveY = currentCentroidYOfTouchesChangedAfter(touchHistory, gestureState._accountsForMovesUpTo); |
|
const movedAfter = gestureState._accountsForMovesUpTo; |
|
const prevX = previousCentroidXOfTouchesChangedAfter(touchHistory, movedAfter); |
|
const x = currentCentroidXOfTouchesChangedAfter(touchHistory, movedAfter); |
|
const prevY = previousCentroidYOfTouchesChangedAfter(touchHistory, movedAfter); |
|
const y = currentCentroidYOfTouchesChangedAfter(touchHistory, movedAfter); |
|
const nextDX = gestureState.dx + (x - prevX); |
|
const nextDY = gestureState.dy + (y - prevY); |
|
|
|
// TODO: This must be filtered intelligently. |
|
const dt = touchHistory.mostRecentTimeStamp - gestureState._accountsForMovesUpTo; |
|
gestureState.vx = (nextDX - gestureState.dx) / dt; |
|
gestureState.vy = (nextDY - gestureState.dy) / dt; |
|
|
|
gestureState.dx = nextDX; |
|
gestureState.dy = nextDY; |
|
gestureState._accountsForMovesUpTo = touchHistory.mostRecentTimeStamp; |
|
}, |
|
|
|
/** |
|
* @param {object} config Enhanced versions of all of the responder callbacks |
|
* that provide not only the typical `ResponderSyntheticEvent`, but also the |
|
* `PanResponder` gesture state. Simply replace the word `Responder` with |
|
* `PanResponder` in each of the typical `onResponder*` callbacks. For |
|
* example, the `config` object would look like: |
|
* |
|
* - `onMoveShouldSetPanResponder: (e, gestureState) => {...}` |
|
* - `onMoveShouldSetPanResponderCapture: (e, gestureState) => {...}` |
|
* - `onStartShouldSetPanResponder: (e, gestureState) => {...}` |
|
* - `onStartShouldSetPanResponderCapture: (e, gestureState) => {...}` |
|
* - `onPanResponderReject: (e, gestureState) => {...}` |
|
* - `onPanResponderGrant: (e, gestureState) => {...}` |
|
* - `onPanResponderStart: (e, gestureState) => {...}` |
|
* - `onPanResponderEnd: (e, gestureState) => {...}` |
|
* - `onPanResponderRelease: (e, gestureState) => {...}` |
|
* - `onPanResponderMove: (e, gestureState) => {...}` |
|
* - `onPanResponderTerminate: (e, gestureState) => {...}` |
|
* - `onPanResponderTerminationRequest: (e, gestureState) => {...}` |
|
* - `onShouldBlockNativeResponder: (e, gestureState) => {...}` |
|
* |
|
* In general, for events that have capture equivalents, we update the |
|
* gestureState once in the capture phase and can use it in the bubble phase |
|
* as well. |
|
* |
|
* Be careful with onStartShould* callbacks. They only reflect updated |
|
* `gestureState` for start/end events that bubble/capture to the Node. |
|
* Once the node is the responder, you can rely on every start/end event |
|
* being processed by the gesture and `gestureState` being updated |
|
* accordingly. (numberActiveTouches) may not be totally accurate unless you |
|
* are the responder. |
|
*/ |
|
create: function (config) { |
|
const interactionState = { |
|
handle: (null: ?number), |
|
}; |
|
const gestureState = { |
|
// Useful for debugging |
|
stateID: Math.random(), |
|
}; |
|
PanResponder._initializeGestureState(gestureState); |
|
const panHandlers = { |
|
onStartShouldSetResponder: function (e) { |
|
return config.onStartShouldSetPanResponder === undefined ? |
|
false : |
|
config.onStartShouldSetPanResponder(e, gestureState); |
|
}, |
|
onMoveShouldSetResponder: function (e) { |
|
return config.onMoveShouldSetPanResponder === undefined ? |
|
false : |
|
config.onMoveShouldSetPanResponder(e, gestureState); |
|
}, |
|
onStartShouldSetResponderCapture: function (e) { |
|
// TODO: Actually, we should reinitialize the state any time |
|
// touches.length increases from 0 active to > 0 active. |
|
if (e.nativeEvent.touches.length === 1) { |
|
PanResponder._initializeGestureState(gestureState); |
|
} |
|
gestureState.numberActiveTouches = e.touchHistory.numberActiveTouches; |
|
return config.onStartShouldSetPanResponderCapture !== undefined ? |
|
config.onStartShouldSetPanResponderCapture(e, gestureState) : |
|
false; |
|
}, |
|
|
|
onMoveShouldSetResponderCapture: function (e) { |
|
const touchHistory = e.touchHistory; |
|
// Responder system incorrectly dispatches should* to current responder |
|
// Filter out any touch moves past the first one - we would have |
|
// already processed multi-touch geometry during the first event. |
|
if (gestureState._accountsForMovesUpTo === touchHistory.mostRecentTimeStamp) { |
|
return false; |
|
} |
|
PanResponder._updateGestureStateOnMove(gestureState, touchHistory); |
|
return config.onMoveShouldSetPanResponderCapture ? |
|
config.onMoveShouldSetPanResponderCapture(e, gestureState) : |
|
false; |
|
}, |
|
|
|
onResponderGrant: function (e) { |
|
if (!interactionState.handle) { |
|
interactionState.handle = InteractionManager.createInteractionHandle(); |
|
} |
|
gestureState.x0 = currentCentroidX(e.touchHistory); |
|
gestureState.y0 = currentCentroidY(e.touchHistory); |
|
gestureState.dx = 0; |
|
gestureState.dy = 0; |
|
if (config.onPanResponderGrant) { |
|
config.onPanResponderGrant(e, gestureState); |
|
} |
|
// TODO: t7467124 investigate if this can be removed |
|
return config.onShouldBlockNativeResponder === undefined ? |
|
true : |
|
config.onShouldBlockNativeResponder(); |
|
}, |
|
|
|
onResponderReject: function (e) { |
|
clearInteractionHandle(interactionState, config.onPanResponderReject, e, gestureState); |
|
}, |
|
|
|
onResponderRelease: function (e) { |
|
clearInteractionHandle(interactionState, config.onPanResponderRelease, e, gestureState); |
|
PanResponder._initializeGestureState(gestureState); |
|
}, |
|
|
|
onResponderStart: function (e) { |
|
const touchHistory = e.touchHistory; |
|
gestureState.numberActiveTouches = touchHistory.numberActiveTouches; |
|
if (config.onPanResponderStart) { |
|
config.onPanResponderStart(e, gestureState); |
|
} |
|
}, |
|
|
|
onResponderMove: function (e) { |
|
const touchHistory = e.touchHistory; |
|
// Guard against the dispatch of two touch moves when there are two |
|
// simultaneously changed touches. |
|
if (gestureState._accountsForMovesUpTo === touchHistory.mostRecentTimeStamp) { |
|
return; |
|
} |
|
// Filter out any touch moves past the first one - we would have |
|
// already processed multi-touch geometry during the first event. |
|
PanResponder._updateGestureStateOnMove(gestureState, touchHistory); |
|
if (config.onPanResponderMove) { |
|
config.onPanResponderMove(e, gestureState); |
|
} |
|
}, |
|
|
|
onResponderEnd: function (e) { |
|
const touchHistory = e.touchHistory; |
|
gestureState.numberActiveTouches = touchHistory.numberActiveTouches; |
|
clearInteractionHandle(interactionState, config.onPanResponderEnd, e, gestureState); |
|
}, |
|
|
|
onResponderTerminate: function (e) { |
|
clearInteractionHandle(interactionState, config.onPanResponderTerminate, e, gestureState); |
|
PanResponder._initializeGestureState(gestureState); |
|
}, |
|
|
|
onResponderTerminationRequest: function (e) { |
|
return config.onPanResponderTerminationRequest === undefined ? |
|
true : |
|
config.onPanResponderTerminationRequest(e, gestureState); |
|
} |
|
}; |
|
return { |
|
panHandlers, |
|
getInteractionHandle(): ?number { |
|
return interactionState.handle; |
|
}, |
|
}; |
|
} |
|
}; |
|
|
|
function clearInteractionHandle( |
|
interactionState: {handle: ?number}, |
|
callback: Function, |
|
event: Object, |
|
gestureState: Object |
|
) { |
|
if (interactionState.handle) { |
|
InteractionManager.clearInteractionHandle(interactionState.handle); |
|
interactionState.handle = null; |
|
} |
|
if (callback) { |
|
callback(event, gestureState); |
|
} |
|
} |
|
|
|
module.exports = PanResponder;
|
|
|