From 0b2a31c1fea41bc7b7c1123000bf4ecb562edc9c Mon Sep 17 00:00:00 2001
From: Tom Hughes <tom@compton.nu>
Date: Thu, 22 Nov 2012 12:12:31 +0000
Subject: [PATCH] Update the Layers control when layers are added or removed

---
 spec/suites/control/Control.LayersSpec.js | 33 +++++++++++++++++++++++
 src/control/Control.Layers.js             | 23 ++++++++++++++++
 2 files changed, 56 insertions(+)

diff --git a/spec/suites/control/Control.LayersSpec.js b/spec/suites/control/Control.LayersSpec.js
index d6ab20a5..78ea1585 100644
--- a/spec/suites/control/Control.LayersSpec.js
+++ b/spec/suites/control/Control.LayersSpec.js
@@ -29,4 +29,37 @@ describe("Control.Layers", function () {
 			expect(spy).not.toHaveBeenCalled();
 		});
 	});
+
+	describe("updates", function () {
+		beforeEach(function () {
+			map.setView([0, 0], 14);
+		});
+
+		it("when an included layer is addded or removed", function () {
+			var baseLayer = L.tileLayer(),
+				overlay = L.marker([0, 0]),
+				layers = L.control.layers({"Base": baseLayer}, {"Overlay": overlay}).addTo(map);
+
+			spyOn(layers, '_update').andCallThrough();
+
+			map.addLayer(overlay);
+			map.removeLayer(overlay);
+
+			expect(layers._update).toHaveBeenCalled();
+			expect(layers._update.callCount).toEqual(2);
+		});
+
+		it("not when a non-included layer is added or removed", function () {
+			var baseLayer = L.tileLayer(),
+				overlay = L.marker([0, 0]),
+				layers = L.control.layers({"Base": baseLayer}).addTo(map);
+
+			spyOn(layers, '_update').andCallThrough();
+
+			map.addLayer(overlay);
+			map.removeLayer(overlay);
+
+			expect(layers._update).not.toHaveBeenCalled();
+		});
+	});
 });
diff --git a/src/control/Control.Layers.js b/src/control/Control.Layers.js
index 186ea025..ce83c915 100644
--- a/src/control/Control.Layers.js
+++ b/src/control/Control.Layers.js
@@ -10,6 +10,7 @@ L.Control.Layers = L.Control.extend({
 
 		this._layers = {};
 		this._lastZIndex = 0;
+		this._handlingClick = false;
 
 		for (var i in baseLayers) {
 			if (baseLayers.hasOwnProperty(i)) {
@@ -28,9 +29,19 @@ L.Control.Layers = L.Control.extend({
 		this._initLayout();
 		this._update();
 
+		map
+		    .on('layeradd', this._onLayerChange, this)
+		    .on('layerremove', this._onLayerChange, this);
+
 		return this._container;
 	},
 
+	onRemove: function (map) {
+		map
+		    .off('layeradd', this._onLayerChange)
+		    .off('layerremove', this._onLayerChange);
+	},
+
 	addBaseLayer: function (layer, name) {
 		this._addLayer(layer, name);
 		this._update();
@@ -133,6 +144,14 @@ L.Control.Layers = L.Control.extend({
 		this._separator.style.display = (overlaysPresent && baseLayersPresent ? '' : 'none');
 	},
 
+	_onLayerChange: function (e) {
+		var id = L.stamp(e.layer);
+
+		if (this._layers[id] && !this._handlingClick) {
+			this._update();
+		}
+	},
+
 	// IE7 bugs out if you create a radio dynamically, so you have to do it this hacky way (see http://bit.ly/PqYLBe)
 	_createRadioElement: function (name, checked) {
 
@@ -184,6 +203,8 @@ L.Control.Layers = L.Control.extend({
 		    inputsLen = inputs.length,
 		    baseLayer;
 
+		this._handlingClick = true;
+
 		for (i = 0; i < inputsLen; i++) {
 			input = inputs[i];
 			obj = this._layers[input.layerId];
@@ -201,6 +222,8 @@ L.Control.Layers = L.Control.extend({
 		if (baseLayer) {
 			this._map.fire('baselayerchange', {layer: baseLayer});
 		}
+
+		this._handlingClick = false;
 	},
 
 	_expand: function () {