@ionic/core
Version:
Base components for Ionic
243 lines (242 loc) • 7.76 kB
JavaScript
/*!
* (C) Ionic http://ionicframework.com - MIT License
*/
import { GESTURE_CONTROLLER } from "./gesture-controller";
import { createPointerEvents } from "./pointer-events";
import { createPanRecognizer } from "./recognizers";
// TODO(FW-2832): types
export const createGesture = (config) => {
let hasCapturedPan = false;
let hasStartedPan = false;
let hasFiredStart = true;
let isMoveQueued = false;
const finalConfig = Object.assign({ disableScroll: false, direction: 'x', gesturePriority: 0, passive: true, maxAngle: 40, threshold: 10 }, config);
const canStart = finalConfig.canStart;
const onWillStart = finalConfig.onWillStart;
const onStart = finalConfig.onStart;
const onEnd = finalConfig.onEnd;
const notCaptured = finalConfig.notCaptured;
const onMove = finalConfig.onMove;
const threshold = finalConfig.threshold;
const passive = finalConfig.passive;
const blurOnStart = finalConfig.blurOnStart;
const detail = {
type: 'pan',
startX: 0,
startY: 0,
startTime: 0,
currentX: 0,
currentY: 0,
velocityX: 0,
velocityY: 0,
deltaX: 0,
deltaY: 0,
currentTime: 0,
event: undefined,
data: undefined,
};
const pan = createPanRecognizer(finalConfig.direction, finalConfig.threshold, finalConfig.maxAngle);
const gesture = GESTURE_CONTROLLER.createGesture({
name: config.gestureName,
priority: config.gesturePriority,
disableScroll: config.disableScroll,
});
const pointerDown = (ev) => {
const timeStamp = now(ev);
if (hasStartedPan || !hasFiredStart) {
return false;
}
updateDetail(ev, detail);
detail.startX = detail.currentX;
detail.startY = detail.currentY;
detail.startTime = detail.currentTime = timeStamp;
detail.velocityX = detail.velocityY = detail.deltaX = detail.deltaY = 0;
detail.event = ev;
// Check if gesture can start
if (canStart && canStart(detail) === false) {
return false;
}
// Release fallback
gesture.release();
// Start gesture
if (!gesture.start()) {
return false;
}
hasStartedPan = true;
if (threshold === 0) {
return tryToCapturePan();
}
pan.start(detail.startX, detail.startY);
return true;
};
const pointerMove = (ev) => {
// fast path, if gesture is currently captured
// do minimum job to get user-land even dispatched
if (hasCapturedPan) {
if (!isMoveQueued && hasFiredStart) {
isMoveQueued = true;
calcGestureData(detail, ev);
requestAnimationFrame(fireOnMove);
}
return;
}
// gesture is currently being detected
calcGestureData(detail, ev);
if (pan.detect(detail.currentX, detail.currentY)) {
if (!pan.isGesture() || !tryToCapturePan()) {
abortGesture();
}
}
};
const fireOnMove = () => {
// Since fireOnMove is called inside a RAF, onEnd() might be called,
// we must double check hasCapturedPan
if (!hasCapturedPan) {
return;
}
isMoveQueued = false;
if (onMove) {
onMove(detail);
}
};
const tryToCapturePan = () => {
if (!gesture.capture()) {
return false;
}
hasCapturedPan = true;
hasFiredStart = false;
// reset start position since the real user-land event starts here
// If the pan detector threshold is big, not resetting the start position
// will cause a jump in the animation equal to the detector threshold.
// the array of positions used to calculate the gesture velocity does not
// need to be cleaned, more points in the positions array always results in a
// more accurate value of the velocity.
detail.startX = detail.currentX;
detail.startY = detail.currentY;
detail.startTime = detail.currentTime;
if (onWillStart) {
onWillStart(detail).then(fireOnStart);
}
else {
fireOnStart();
}
return true;
};
const blurActiveElement = () => {
if (typeof document !== 'undefined') {
const activeElement = document.activeElement;
if (activeElement === null || activeElement === void 0 ? void 0 : activeElement.blur) {
activeElement.blur();
}
}
};
const fireOnStart = () => {
if (blurOnStart) {
blurActiveElement();
}
if (onStart) {
onStart(detail);
}
hasFiredStart = true;
};
const reset = () => {
hasCapturedPan = false;
hasStartedPan = false;
isMoveQueued = false;
hasFiredStart = true;
gesture.release();
};
// END *************************
const pointerUp = (ev) => {
const tmpHasCaptured = hasCapturedPan;
const tmpHasFiredStart = hasFiredStart;
reset();
if (!tmpHasFiredStart) {
return;
}
calcGestureData(detail, ev);
// Try to capture press
if (tmpHasCaptured) {
if (onEnd) {
onEnd(detail);
}
return;
}
// Not captured any event
if (notCaptured) {
notCaptured(detail);
}
};
const pointerEvents = createPointerEvents(finalConfig.el, pointerDown, pointerMove, pointerUp, {
capture: false,
passive,
});
const abortGesture = () => {
reset();
pointerEvents.stop();
if (notCaptured) {
notCaptured(detail);
}
};
return {
enable(enable = true) {
if (!enable) {
if (hasCapturedPan) {
pointerUp(undefined);
}
reset();
}
pointerEvents.enable(enable);
},
destroy() {
gesture.destroy();
pointerEvents.destroy();
},
};
};
const calcGestureData = (detail, ev) => {
if (!ev) {
return;
}
const prevX = detail.currentX;
const prevY = detail.currentY;
const prevT = detail.currentTime;
updateDetail(ev, detail);
const currentX = detail.currentX;
const currentY = detail.currentY;
const timestamp = (detail.currentTime = now(ev));
const timeDelta = timestamp - prevT;
if (timeDelta > 0 && timeDelta < 100) {
const velocityX = (currentX - prevX) / timeDelta;
const velocityY = (currentY - prevY) / timeDelta;
detail.velocityX = velocityX * 0.7 + detail.velocityX * 0.3;
detail.velocityY = velocityY * 0.7 + detail.velocityY * 0.3;
}
detail.deltaX = currentX - detail.startX;
detail.deltaY = currentY - detail.startY;
detail.event = ev;
};
const updateDetail = (ev, detail) => {
// get X coordinates for either a mouse click
// or a touch depending on the given event
let x = 0;
let y = 0;
if (ev) {
const changedTouches = ev.changedTouches;
if (changedTouches && changedTouches.length > 0) {
const touch = changedTouches[0];
x = touch.clientX;
y = touch.clientY;
}
else if (ev.pageX !== undefined) {
x = ev.pageX;
y = ev.pageY;
}
}
detail.currentX = x;
detail.currentY = y;
};
const now = (ev) => {
return ev.timeStamp || Date.now();
};
export { GESTURE_CONTROLLER };