https://geo.stat.gov.lv/stage2/lib/leaflet-draw/draw/handler/Draw.Polygon.js

1/**
2 * @class L.Draw.Polygon
3 * @aka Draw.Polygon
4 * @inherits L.Draw.Polyline
5 */
6L.Draw.Polygon = L.Draw.Polyline.extend({
7	statics: {
8		TYPE: 'polygon'
9	},
10
11	Poly: L.Polygon,
12
13	options: {
14		showArea: false,
15		shapeOptions: {
16			stroke: true,
17			color: '#3388ff',
18			weight: 4,
19			opacity: 0.5,
20			fill: true,
21			fillColor: null, //same as color by default
22			fillOpacity: 0.2,
23			clickable: true
24		},
25		metric: true // Whether to use the metric measurement system or imperial
26	},
27
28	// @method initialize(): void
29	initialize: function (map, options) {
30		L.Draw.Polyline.prototype.initialize.call(this, map, options);
31
32		// Save the type so super can fire, need to do this as cannot do this.TYPE :(
33		this.type = L.Draw.Polygon.TYPE;
34	},
35
36	_updateFinishHandler: function () {
37		var markerCount = this._markers.length;
38
39		// The first marker should have a click handler to close the polygon
40		if (markerCount === 1) {
41			this._markers[0].on('click', this._finishShape, this);
42		}
43
44		// Add and update the double click handler
45		if (markerCount > 2) {
46			this._markers[markerCount - 1].on('dblclick', this._finishShape, this);
47			// Only need to remove handler if has been added before
48			if (markerCount > 3) {
49				this._markers[markerCount - 2].off('dblclick', this._finishShape, this);
50			}
51		}
52	},
53
54	_getTooltipText: function () {
55		var text, subtext;
56
57		if (this._markers.length === 0) {
58			text = L.drawLocal.draw.handlers.polygon.tooltip.start;
59		} else if (this._markers.length < 3) {
60			text = L.drawLocal.draw.handlers.polygon.tooltip.cont;
61		} else {
62			text = L.drawLocal.draw.handlers.polygon.tooltip.end;
63			subtext = this._getMeasurementString();
64		}
65
66		return {
67			text: text,
68			subtext: subtext
69		};
70	},
71
72	_getMeasurementString: function () {
73		var area = this._area;
74
75		if (!area) {
76			return null;
77		}
78
79		return L.GeometryUtil.readableArea(area, this.options.metric);
80	},
81
82	_shapeIsValid: function () {
83		return this._markers.length >= 3;
84	},
85
86	_vertexChanged: function (latlng, added) {
87		var latLngs;
88
89		// Check to see if we should show the area
90		if (!this.options.allowIntersection && this.options.showArea) {
91			latLngs = this._poly.getLatLngs();
92
93			this._area = L.GeometryUtil.geodesicArea(latLngs);
94		}
95
96		L.Draw.Polyline.prototype._vertexChanged.call(this, latlng, added);
97	},
98
99	_cleanUpShape: function () {
100		var markerCount = this._markers.length;
101
102		if (markerCount > 0) {
103			this._markers[0].off('click', this._finishShape, this);
104
105			if (markerCount > 2) {
106				this._markers[markerCount - 1].off('dblclick', this._finishShape, this);
107			}
108		}
109	}
110});