src/plugins/leaflet-draw/edit/handler/EditToolbar.Delete.js

/**
 * @class L.EditToolbar.Delete
 * @aka EditToolbar.Delete
 */
L.EditToolbar.Delete = L.Handler.extend({
	statics: {
		TYPE: 'remove' // not delete as delete is reserved in js
	},

	includes: L.Mixin.Events,

	// @method intialize(): void
	initialize: function (map, options) {
		L.Handler.prototype.initialize.call(this, map);

		L.Util.setOptions(this, options);

		// Store the selectable layer group for ease of access
		this._deletableLayers = this.options.featureGroup;

		if (!(this._deletableLayers instanceof L.FeatureGroup)) {
			throw new Error('options.featureGroup must be a L.FeatureGroup');
		}

		// Save the type so super can fire, need to do this as cannot do this.TYPE :(
		this.type = L.EditToolbar.Delete.TYPE;
	},

	// @method enable(): void
	// Enable the delete toolbar
	enable: function () {
		if (this._enabled || !this._hasAvailableLayers()) {
			return;
		}
		this.fire('enabled', { handler: this.type });

		this._map.fire(L.Draw.Event.DELETESTART, { handler: this.type });

		L.Handler.prototype.enable.call(this);

		this._deletableLayers
			.on('layeradd', this._enableLayerDelete, this)
			.on('layerremove', this._disableLayerDelete, this);
	},

	// @method disable(): void
	// Disable the delete toolbar
	disable: function () {
		if (!this._enabled) {
			return;
		}

		this._deletableLayers
			.off('layeradd', this._enableLayerDelete, this)
			.off('layerremove', this._disableLayerDelete, this);

		L.Handler.prototype.disable.call(this);

		this._map.fire(L.Draw.Event.DELETESTOP, { handler: this.type });

		this.fire('disabled', { handler: this.type });
	},

	// @method addHooks(): void
	// Add listener hooks to this handler
	addHooks: function () {
		var map = this._map;

		if (map) {
			map.getContainer().focus();

			this._deletableLayers.eachLayer(this._enableLayerDelete, this);
			this._deletedLayers = new L.LayerGroup();

			this._tooltip = new L.Draw.Tooltip(this._map);
			this._tooltip.updateContent({ text: L.drawLocal.edit.handlers.remove.tooltip.text });

			this._map.on('mousemove', this._onMouseMove, this);
		}
	},

	// @method removeHooks(): void
	// Remove listener hooks from this handler
	removeHooks: function () {
		if (this._map) {
			this._deletableLayers.eachLayer(this._disableLayerDelete, this);
			this._deletedLayers = null;

			this._tooltip.dispose();
			this._tooltip = null;

			this._map.off('mousemove', this._onMouseMove, this);
		}
	},

	// @method revertLayers(): void
	// Revert the deleted layers back to their prior state.
	revertLayers: function () {
		// Iterate of the deleted layers and add them back into the featureGroup
		this._deletedLayers.eachLayer(function (layer) {
			this._deletableLayers.addLayer(layer);
			layer.fire('revert-deleted', { layer: layer });
		}, this);
	},

	// @method save(): void
	// Save deleted layers
	save: function () {
		this._map.fire(L.Draw.Event.DELETED, { layers: this._deletedLayers });
	},

	// @method removeAllLayers(): void
	// Remove all delateable layers
	removeAllLayers: function(){
		// Iterate of the delateable layers and add remove them
		this._deletableLayers.eachLayer(function (layer) {
			this._removeLayer({layer:layer});
		}, this);
		this.save();
	},

	_enableLayerDelete: function (e) {
		var layer = e.layer || e.target || e;

		layer.on('click', this._removeLayer, this);
	},

	_disableLayerDelete: function (e) {
		var layer = e.layer || e.target || e;

		layer.off('click', this._removeLayer, this);

		// Remove from the deleted layers so we can't accidentally revert if the user presses cancel
		this._deletedLayers.removeLayer(layer);
	},

	_removeLayer: function (e) {
		var layer = e.layer || e.target || e;

		this._deletableLayers.removeLayer(layer);

		this._deletedLayers.addLayer(layer);

		layer.fire('deleted');
	},

	_onMouseMove: function (e) {
		this._tooltip.updatePosition(e.latlng);
	},

	_hasAvailableLayers: function () {
		return this._deletableLayers.getLayers().length !== 0;
	}
});