From fc1d79a9b072479a559df4b29067ebc388045898 Mon Sep 17 00:00:00 2001
From: davidsulc <david@davidsulc.com>
Date: Wed, 2 May 2012 14:38:43 -0400
Subject: [PATCH] trigger event to load more books when a user scrolls near the
 end

---
 assets/javascript/app.library_app.book_list.js | 17 ++++++++++++++++-
 assets/javascript/app.library_app.js           |  1 +
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/assets/javascript/app.library_app.book_list.js b/assets/javascript/app.library_app.book_list.js
index 88dd9f8..3454fce 100644
--- a/assets/javascript/app.library_app.book_list.js
+++ b/assets/javascript/app.library_app.book_list.js
@@ -11,19 +11,34 @@ MyApp.LibraryApp.BookList = function(){
     itemView: BookView,
   
     initialize: function(){
-      _.bindAll(this, "showMessage");
+      _.bindAll(this, "showMessage", "loadMoreBooks");
       var self = this;
       MyApp.vent.on("search:error", function(){ self.showMessage("Error, please retry later :s") });
       MyApp.vent.on("search:noSearchTerm", function(){ self.showMessage("Hummmm, can do better :)") });
       MyApp.vent.on("search:noResults", function(){ self.showMessage("No books found") });
     },
     
+    events: {
+      'scroll': 'loadMoreBooks'
+    },
+    
     appendHtml: function(collectionView, itemView){
       collectionView.$(".books").append(itemView.el);
     },
   
     showMessage: function(message){
       this.$('.books').html('<h1 class="notFound">' + message + '</h1>');
+    },
+    
+    loadMoreBooks: function(){
+      var totalHeight = this.$('> div').height(),
+          scrollTop = this.$el.scrollTop() + this.$el.height(),
+          margin = 200;
+          
+      // if we are closer than 'margin' to the end of the content, load more books
+      if (scrollTop + margin >= totalHeight) {
+        MyApp.vent.trigger("search:more");
+      }
     }
   });
   
diff --git a/assets/javascript/app.library_app.js b/assets/javascript/app.library_app.js
index ee93249..4f74361 100644
--- a/assets/javascript/app.library_app.js
+++ b/assets/javascript/app.library_app.js
@@ -19,6 +19,7 @@ MyApp.LibraryApp = function(){
       var self = this;
       _.bindAll(this, "search");
       MyApp.vent.on("search:term", function(term){ self.search(term); });
+      MyApp.vent.on("search:more", function(){ console.log("Need to load more books!"); });
       
       // the number of books we fetch each time
       this.maxResults = 40;