tp-table/column-resizer.js

69 lines
2.1 KiB
JavaScript

export default class ColumResizer {
constructor(wrap, handleSelector) {
this._handleSelector = handleSelector;
this._mouseDown = this._mouseDown.bind(this);
this._dragging = this._dragging.bind(this);
this._draggingEnd = this._draggingEnd.bind(this);
this._trackingStarted = false;
// Amount of pixels the handle must be moved before its registered as a tracking gesture.
this.threshold = 5;
wrap.addEventListener('mousedown', this._mouseDown);
}
_mouseDown(e) {
const handle = e.composedPath().find(node => node.matches && node.matches(this._handleSelector));
if (!handle) return;
this._cHandle = handle;
this._startX = e.pageX;
this._watchDrag();
}
_watchDrag() {
window.addEventListener('mousemove', this._dragging);
window.addEventListener('mouseup', this._draggingEnd);
}
_stopWatchDrag() {
window.removeEventListener('mousemove', this._dragging);
window.removeEventListener('mouseup', this._draggingEnd);
}
_dragging(e) {
this._dx = e.pageX - this._startX;
if (this._trackingStarted === false && Math.abs(this._dx) >= this.threshold) {
this._trackingStarted = true;
this._clearSelection();
this._cHandle.dispatchEvent(new CustomEvent('track', { detail: { state: 'start', dx: this._dx }, bubbles: true, composed: true }));
}
if (this._trackingStarted === true) {
this._cHandle.dispatchEvent(new CustomEvent('track', { detail: { state: 'track', dx: this._dx }, bubbles: true, composed: true }));
}
}
_draggingEnd(e) {
this._dx = e.pageX - this._startX;
this._trackingStarted = false;
this._cHandle.dispatchEvent(new CustomEvent('track', { detail: { state: 'end', dx: this._dx }, bubbles: true, composed: true }));
this._stopWatchDrag();
this._cHandle = null;
this._startX = 0;
this._clearSelection();
}
_clearSelection() {
const sel = window.getSelection ? window.getSelection() : document.selection;
if (sel) {
if (sel.removeAllRanges) {
sel.removeAllRanges();
} else if (sel.empty) {
sel.empty();
}
}
}
}