From f8c57df2919258464d6c6ce9b17fba6d0cc8ce06 Mon Sep 17 00:00:00 2001
From: sttawm <mmww88wwmm@gmail.com>
Date: Fri, 17 Jul 2015 13:07:07 -0700
Subject: [PATCH 1/2] add a 'loading' event to a layer

---
 src/Layer.js | 27 +++++++++++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/src/Layer.js b/src/Layer.js
index 503fc4c..88d5f09 100644
--- a/src/Layer.js
+++ b/src/Layer.js
@@ -248,6 +248,8 @@ ms.layer = function(load, unload) {
     // flush the cache, clearing no-longer-needed tiles
     cache.flush();
 
+    checkIsLoading();
+
     // dispatch the move event
     layer.dispatch({type: "move"});
   }
@@ -265,6 +267,17 @@ ms.layer = function(load, unload) {
     }
   }
 
+  var checkIsLoading = (function() {
+    var wasLoading;
+    return function() {
+      var isLoading = layer.isLoading();
+      if (isLoading !== wasLoading) {
+        wasLoading = isLoading;
+        layer.dispatch({type: "loading", loading: isLoading});
+      }
+    };
+  })();
+
   layer.map = function(x) {
     if (!arguments.length) return map;
     if (map) {
@@ -279,7 +292,7 @@ ms.layer = function(load, unload) {
     if (map) {
       map.svgContainer().appendChild(container);
       if (layer.init) layer.init(container);
-      map.on("move", move).on("resize", move);
+      map.on("move", move).on("resize", move)
       move();
     }
     return layer;
@@ -308,6 +321,16 @@ ms.layer = function(load, unload) {
     return layer;
   };
 
+  layer.isLoading = function() {
+    var tiles = cache.locks();
+    for (key in tiles) {
+      var tile = tiles[key];
+      if (!tile.ready)
+        return true;
+    }
+    return false;
+  };
+
   layer.transform = function(x) {
     if (!arguments.length) return transform;
     transform = x;
@@ -336,7 +359,7 @@ ms.layer = function(load, unload) {
   };
 
   layer.dispatch = ms.dispatch(layer);
-  layer.on("load", cleanup);
+  layer.on("load", cleanup).on("load", checkIsLoading);
 
   return layer;
 };

From 6ef639f3654b07aabefbbd9ef3ddcc2f5fc69140 Mon Sep 17 00:00:00 2001
From: sttawm <mmww88wwmm@gmail.com>
Date: Fri, 17 Jul 2015 13:09:22 -0700
Subject: [PATCH 2/2] fix missing semicolon

---
 src/Layer.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Layer.js b/src/Layer.js
index 88d5f09..0ba13cf 100644
--- a/src/Layer.js
+++ b/src/Layer.js
@@ -292,7 +292,7 @@ ms.layer = function(load, unload) {
     if (map) {
       map.svgContainer().appendChild(container);
       if (layer.init) layer.init(container);
-      map.on("move", move).on("resize", move)
+      map.on("move", move).on("resize", move);
       move();
     }
     return layer;