@ionic/core
Version:
Base components for Ionic
277 lines (276 loc) • 9.1 kB
JavaScript
import { hapticSelectionChanged, hapticSelectionEnd, hapticSelectionStart } from '../../utils/haptic';
export class ReorderGroup {
constructor() {
this.lastToIndex = -1;
this.cachedHeights = [];
this.scrollElTop = 0;
this.scrollElBottom = 0;
this.scrollElInitial = 0;
this.containerTop = 0;
this.containerBottom = 0;
this.state = 0;
this.disabled = true;
}
disabledChanged() {
if (this.gesture) {
this.gesture.setDisabled(this.disabled);
}
const a = { a: 2 };
delete a.a;
}
async componentDidLoad() {
const contentEl = this.el.closest('ion-content');
if (contentEl) {
await contentEl.componentOnReady();
this.scrollEl = await contentEl.getScrollElement();
}
this.gesture = (await import('../../utils/gesture')).createGesture({
el: this.doc.body,
queue: this.queue,
gestureName: 'reorder',
gesturePriority: 90,
threshold: 0,
direction: 'y',
passive: false,
canStart: detail => this.canStart(detail),
onStart: ev => this.onStart(ev),
onMove: ev => this.onMove(ev),
onEnd: () => this.onEnd(),
});
this.disabledChanged();
}
componentDidUnload() {
this.onEnd();
if (this.gesture) {
this.gesture.destroy();
this.gesture = undefined;
}
}
complete(listOrReorder) {
return Promise.resolve(this.completeSync(listOrReorder));
}
canStart(ev) {
if (this.selectedItemEl || this.state !== 0) {
return false;
}
const target = ev.event.target;
const reorderEl = target.closest('ion-reorder');
if (!reorderEl) {
return false;
}
const item = findReorderItem(reorderEl, this.el);
if (!item) {
return false;
}
ev.data = item;
return true;
}
onStart(ev) {
ev.event.preventDefault();
const item = this.selectedItemEl = ev.data;
const heights = this.cachedHeights;
heights.length = 0;
const el = this.el;
const children = el.children;
if (!children || children.length === 0) {
return;
}
let sum = 0;
for (let i = 0; i < children.length; i++) {
const child = children[i];
sum += child.offsetHeight;
heights.push(sum);
child.$ionIndex = i;
}
const box = el.getBoundingClientRect();
this.containerTop = box.top;
this.containerBottom = box.bottom;
if (this.scrollEl) {
const scrollBox = this.scrollEl.getBoundingClientRect();
this.scrollElInitial = this.scrollEl.scrollTop;
this.scrollElTop = scrollBox.top + AUTO_SCROLL_MARGIN;
this.scrollElBottom = scrollBox.bottom - AUTO_SCROLL_MARGIN;
}
else {
this.scrollElInitial = 0;
this.scrollElTop = 0;
this.scrollElBottom = 0;
}
this.lastToIndex = indexForItem(item);
this.selectedItemHeight = item.offsetHeight;
this.state = 1;
item.classList.add(ITEM_REORDER_SELECTED);
hapticSelectionStart();
}
onMove(ev) {
const selectedItem = this.selectedItemEl;
if (!selectedItem) {
return;
}
const scroll = this.autoscroll(ev.currentY);
const top = this.containerTop - scroll;
const bottom = this.containerBottom - scroll;
const currentY = Math.max(top, Math.min(ev.currentY, bottom));
const deltaY = scroll + currentY - ev.startY;
const normalizedY = currentY - top;
const toIndex = this.itemIndexForTop(normalizedY);
if (toIndex !== this.lastToIndex) {
const fromIndex = indexForItem(selectedItem);
this.lastToIndex = toIndex;
hapticSelectionChanged();
this.reorderMove(fromIndex, toIndex);
}
selectedItem.style.transform = `translateY(${deltaY}px)`;
}
onEnd() {
const selectedItem = this.selectedItemEl;
this.state = 2;
if (!selectedItem) {
this.state = 0;
return;
}
const toIndex = this.lastToIndex;
const fromIndex = indexForItem(selectedItem);
if (toIndex === fromIndex) {
selectedItem.style.transition = 'transform 200ms ease-in-out';
setTimeout(() => this.completeSync(), 200);
}
else {
this.ionItemReorder.emit({
from: fromIndex,
to: toIndex,
complete: this.completeSync.bind(this)
});
}
hapticSelectionEnd();
}
completeSync(listOrReorder) {
const selectedItemEl = this.selectedItemEl;
if (selectedItemEl && this.state === 2) {
const children = this.el.children;
const len = children.length;
const toIndex = this.lastToIndex;
const fromIndex = indexForItem(selectedItemEl);
if (listOrReorder === true) {
const ref = (fromIndex < toIndex)
? children[toIndex + 1]
: children[toIndex];
this.el.insertBefore(selectedItemEl, ref);
}
if (Array.isArray(listOrReorder)) {
listOrReorder = reorderArray(listOrReorder, fromIndex, toIndex);
}
for (let i = 0; i < len; i++) {
children[i].style['transform'] = '';
}
selectedItemEl.style.transition = '';
selectedItemEl.classList.remove(ITEM_REORDER_SELECTED);
this.selectedItemEl = undefined;
this.state = 0;
}
return listOrReorder;
}
itemIndexForTop(deltaY) {
const heights = this.cachedHeights;
let i = 0;
for (i = 0; i < heights.length; i++) {
if (heights[i] > deltaY) {
break;
}
}
return i;
}
reorderMove(fromIndex, toIndex) {
const itemHeight = this.selectedItemHeight;
const children = this.el.children;
for (let i = 0; i < children.length; i++) {
const style = children[i].style;
let value = '';
if (i > fromIndex && i <= toIndex) {
value = `translateY(${-itemHeight}px)`;
}
else if (i < fromIndex && i >= toIndex) {
value = `translateY(${itemHeight}px)`;
}
style['transform'] = value;
}
}
autoscroll(posY) {
if (!this.scrollEl) {
return 0;
}
let amount = 0;
if (posY < this.scrollElTop) {
amount = -SCROLL_JUMP;
}
else if (posY > this.scrollElBottom) {
amount = SCROLL_JUMP;
}
if (amount !== 0) {
this.scrollEl.scrollBy(0, amount);
}
return this.scrollEl.scrollTop - this.scrollElInitial;
}
hostData() {
return {
class: {
'reorder-enabled': !this.disabled,
'reorder-list-active': this.state !== 0,
}
};
}
static get is() { return "ion-reorder-group"; }
static get properties() { return {
"complete": {
"method": true
},
"disabled": {
"type": Boolean,
"attr": "disabled",
"watchCallbacks": ["disabledChanged"]
},
"doc": {
"context": "document"
},
"el": {
"elementRef": true
},
"queue": {
"context": "queue"
},
"state": {
"state": true
}
}; }
static get events() { return [{
"name": "ionItemReorder",
"method": "ionItemReorder",
"bubbles": true,
"cancelable": true,
"composed": true
}]; }
static get style() { return "/**style-placeholder:ion-reorder-group:**/"; }
}
function indexForItem(element) {
return element['$ionIndex'];
}
function findReorderItem(node, container) {
let parent;
while (node) {
parent = node.parentElement;
if (parent === container) {
return node;
}
node = parent;
}
return undefined;
}
const AUTO_SCROLL_MARGIN = 60;
const SCROLL_JUMP = 10;
const ITEM_REORDER_SELECTED = 'reorder-selected';
function reorderArray(array, from, to) {
const element = array[from];
array.splice(from, 1);
array.splice(to, 0, element);
return array.slice();
}