ant-design-vue/components/vc-virtual-list/hooks/useMobileTouchMove.js

72 lines
1.5 KiB
JavaScript

import { watch } from 'vue';
const SMOOTH_PTG = 14 / 15;
export default function useMobileTouchMove(inVirtual, listRef, callback) {
let touched = false;
let touchY = 0;
let element = null;
// Smooth scroll
let interval = null;
let cleanUpEvents;
const onTouchMove = e => {
if (touched) {
const currentY = Math.ceil(e.touches[0].pageY);
let offsetY = touchY - currentY;
touchY = currentY;
if (callback(offsetY)) {
e.preventDefault();
}
// Smooth interval
clearInterval(interval);
interval = setInterval(() => {
offsetY *= SMOOTH_PTG;
if (!callback(offsetY, true) || Math.abs(offsetY) <= 0.1) {
clearInterval(interval);
}
}, 16);
}
};
const onTouchEnd = () => {
touched = false;
cleanUpEvents();
};
const onTouchStart = e => {
cleanUpEvents();
if (e.touches.length === 1 && !touched) {
touched = true;
touchY = Math.ceil(e.touches[0].pageY);
element = e.target;
element.addEventListener('touchmove', onTouchMove);
element.addEventListener('touchend', onTouchEnd);
}
};
cleanUpEvents = () => {
if (element) {
element.removeEventListener('touchmove', onTouchMove);
element.removeEventListener('touchend', onTouchEnd);
}
};
watch(inVirtual, val => {
listRef.current.removeEventListener('touchstart', onTouchStart);
cleanUpEvents();
clearInterval(interval);
if (val.value) {
listRef.current.addEventListener('touchstart', onTouchStart);
}
});
}