Merged Joe's patch for backward compatibility

Author: bhaskarvk

.gitignore

@@ -4,3 +4,5 @@
 node_modules
 inst/htmlwidgets/sources
 *.swp
+inst/examples/rsconnect
+inst/examples/*.html

R/leaflet.R

@@ -45,10 +45,29 @@ leaflet = function(data = NULL, width = NULL, height = NULL,
       defaultHeight = 400,
       padding = padding,
       browser.fill = TRUE
-    )
+    ),
+    preRenderHook = function(widget) {
+      if (!is.null(widget$jsHooks$render)) {
+        widget$jsHooks$render <- lapply(widget$jsHooks$render, function(hook) {
+          if (is.list(hook)) {
+            hook$code <- sprintf(hookWrapperTemplate, paste(hook$code, collapse = "\n"))
+          } else if (is.character(hook)) {
+            hook <- sprintf(hookWrapperTemplate, paste(hook, collapse = "\n"))
+          } else {
+            stop("Unknown hook class ", class(hook))
+          }
+          hook
+        })
+      }
+      widget
+    }
   )
 }
 
+hookWrapperTemplate <- "function(el, x, data) {
+  return (%s).call(this.getMap(), el, x, data);
+}"
+
 getMapData = function(map) {
   attr(map$x, "leafletData", exact = TRUE)
 }

inst/examples/minimap.R

@@ -34,7 +34,7 @@ m %>%
              toggleDisplay = T) %>%
   htmlwidgets::onRender("
     function(el, x) {
-      var myMap = this.getMap();
+      var myMap = this;
       myMap.on('baselayerchange',
         function (e) {
           myMap.minimap.changeLayer(L.tileLayer.provider(e.name));
@@ -72,7 +72,7 @@ leaflet() %>% addTiles() %>%
   addMiniMap() %>%
   htmlwidgets::onRender("
     function(el, t) {
-      var myMap = this.getMap();
+      var myMap = this;
 
       var pubs = myMap.layerManager._byGroup.pubs;
       var pubs2 = new L.FeatureGroup();
@@ -106,7 +106,7 @@ m %>%
              toggleDisplay = T) %>%
   htmlwidgets::onRender("
     function(el, t) {
-      var myMap = this.getMap();
+      var myMap = this;
 
       var pubs = myMap.layerManager._byGroup.pubs;
       var pubs2 = new L.FeatureGroup();

inst/examples/proj4Leaflet.R

@@ -57,7 +57,7 @@ leaflet(mapOptions = list(crs=crs(crsClass='L.CRS.Simple'), minZoom= -5)) %>%
   setMaxBounds(bounds[1], bounds[2], bounds[3], bounds[4]) %>%
   htmlwidgets::onRender("
   function(el, t) {
-    var myMap = this.getMap();
+    var myMap = this;
     var bounds = myMap.getBounds();
   	var image = new L.ImageOverlay(
                       'http://leafletjs.com/examples/crs-simple/uqm_map_full.png',
@@ -108,7 +108,7 @@ leaflet(mapOptions =
         fillOpacity: 1,
       };
 
-      var myMap = this.getMap();
+      var myMap = this;
       var layers = myMap._layers;
       for(var i in layers) {
         var layer = layers[i];