Custom events implementation

Gruntfile.js

@@ -4,6 +4,7 @@ var semver = require('semver'),
       'src/version.js',
       'src/utils.js',
       'src/event_target.js',
+      'src/event_bus.js',
       'src/persistent_storage.js',
       'src/request_cache.js',
       'src/transport.js',

src/dataset.js

@@ -10,13 +10,22 @@ var Dataset = (function() {
     utils.bindAll(this);
 
     if (o.template && !o.engine) {
-      throw new Error('no template engine specified');
+      $.error('no template engine specified');
+    }
+
+    if (!o.local && !o.prefetch && !o.remote) {
+      $.error('one of local, prefetch, or remote is requried');
     }
 
     this.name = o.name;
     this.limit = o.limit || 5;
     this.template = compileTemplate(o.template, o.engine);
 
+    // used in #initialize
+    this.local = o.local;
+    this.prefetch = o.prefetch;
+    this.remote = o.remote;
+
     this.keys = {
       version: 'version',
       protocol: 'protocol',
@@ -40,6 +49,7 @@ var Dataset = (function() {
 
     _loadPrefetchData: function(o) {
       var that = this,
+          deferred,
           version = this.storage.get(this.keys.version),
           protocol = this.storage.get(this.keys.protocol),
           itemHash = this.storage.get(this.keys.itemHash),
@@ -55,12 +65,16 @@ var Dataset = (function() {
           itemHash: itemHash,
           adjacencyList: adjacencyList
         });
+
+        deferred = $.Deferred().resolve();
       }
 
       else {
-        $.getJSON(o.url).done(processPrefetchData);
+        deferred = $.getJSON(o.url).done(processPrefetchData);
       }
 
+      return deferred;
+
       function processPrefetchData(data) {
         var filteredData = o.filter ? o.filter(data) : data,
             processedData = that._processData(filteredData),
@@ -256,17 +270,20 @@ var Dataset = (function() {
 
     // the contents of this function are broken out of the constructor
     // to help improve the testability of datasets
-    initialize: function(o) {
-      if (!o.local && !o.prefetch && !o.remote) {
-        throw new Error('one of local, prefetch, or remote is requried');
-      }
+    initialize: function() {
+      var deferred;
+
+      this.local && this._processLocalData(this.local);
+      this.transport = this.remote ? new Transport(this.remote) : null;
 
-      this.transport = o.remote ? new Transport(o.remote) : null;
+      deferred = this.prefetch ?
+        this._loadPrefetchData(this.prefetch) :
+        $.Deferred().resolve();
 
-      o.local && this._processLocalData(o.local);
-      o.prefetch && this._loadPrefetchData(o.prefetch);
+      this.local = this.prefetch = this.remote = null;
+      this.initialize = function() { return deferred; };
 
-      return this;
+      return deferred;
     },
 
     getSuggestions: function(query, callback) {

src/dropdown_view.js

@@ -52,7 +52,7 @@ var DropdownView = (function() {
 
     _handleSelection: function($e) {
       var $suggestion = $($e.currentTarget);
-      this.trigger('suggestionSelected', formatDataForSuggestion($suggestion));
+      this.trigger('suggestionSelected', getSuggestionData($suggestion));
     },
 
     _show: function() {
@@ -94,7 +94,7 @@ var DropdownView = (function() {
       }
 
       $underCursor = $suggestions.eq(nextIndex).addClass('tt-is-under-cursor');
-      this.trigger('cursorMoved', { value: $underCursor.data('value') });
+      this.trigger('cursorMoved', getSuggestionData($underCursor));
     },
 
     _getSuggestions: function() {
@@ -166,15 +166,13 @@ var DropdownView = (function() {
           .filter('.tt-is-under-cursor')
           .first();
 
-      return $suggestion.length > 0 ?
-        formatDataForSuggestion($suggestion) : null;
+      return $suggestion.length > 0 ? getSuggestionData($suggestion) : null;
     },
 
     getFirstSuggestion: function() {
       var $suggestion = this._getSuggestions().first();
 
-      return $suggestion.length > 0 ?
-        formatDataForSuggestion($suggestion) : null;
+      return $suggestion.length > 0 ? getSuggestionData($suggestion) : null;
     },
 
     renderSuggestions: function(query, dataset, suggestions) {
@@ -209,7 +207,7 @@ var DropdownView = (function() {
 
           $el = $(elBuilder.firstChild)
           .css(css.suggestion)
-          .data('value', suggestion.value);
+          .data('suggestion', suggestion);
 
           $el.children().each(function() {
             $(this).css(css.suggestionChild);
@@ -219,9 +217,7 @@ var DropdownView = (function() {
         });
       }
 
-      $dataset.find('> .tt-suggestions')
-      .data({ query: query, dataset: dataset.name })
-      .append(fragment);
+      $dataset.find('> .tt-suggestions').append(fragment);
 
       this.trigger('suggestionsRendered');
     },
@@ -242,13 +238,10 @@ var DropdownView = (function() {
 
   return DropdownView;
 
-  function formatDataForSuggestion($suggestion) {
-    var $suggestions = $suggestion.parents('.tt-suggestions').first();
+  // helper functions
+  // ----------------
 
-    return {
-      value: $suggestion.data('value'),
-      query: $suggestions.data('query'),
-      dataset: $suggestions.data('dataset')
-    };
+  function getSuggestionData($el) {
+    return $el.data('suggestion');
   }
 })();

src/event_bus.js

@@ -0,0 +1,30 @@
+/*
+ * typeahead.js
+ * https://github.com/twitter/typeahead
+ * Copyright 2013 Twitter, Inc. and other contributors; Licensed MIT
+ */
+
+var EventBus = (function() {
+  var namespace = 'typeahead:';
+
+  function EventBus(o) {
+    if (!o || !o.el) {
+      $.error('EventBus initialized without el');
+    }
+
+    this.$el = $(o.el);
+  }
+
+  utils.mixin(EventBus.prototype, {
+    // public methods
+    // --------------
+
+    trigger: function(type) {
+      var args = [].slice.call(arguments, 1);
+
+      this.$el.trigger(namespace + type, args);
+    }
+  });
+
+  return EventBus;
+})();

src/typeahead.js

@@ -5,7 +5,7 @@
  */
 
 (function() {
-  var datasetCache = {}, methods;
+  var datasetCache = {}, viewKey = 'ttView', methods;
 
   methods = {
     initialize: function(datasetDefs) {
@@ -14,37 +14,51 @@
       datasetDefs = utils.isArray(datasetDefs) ? datasetDefs : [datasetDefs];
 
       if (this.length === 0) {
-        throw new Error('typeahead initialized without DOM element');
+        $.error('typeahead initialized without DOM element');
       }
 
       if (datasetDefs.length === 0) {
-        throw new Error('no datasets provided');
+        $.error('no datasets provided');
       }
 
       datasets = utils.map(datasetDefs, function(o) {
         o.name = o.name || utils.getUniqueId();
 
         return datasetCache[o.name] ?
           datasetCache[o.name] :
-          datasetCache[o.name] = new Dataset(o).initialize(o);
+          datasetCache[o.name] = new Dataset(o);
       });
 
-      return this.each(function() {
+      return this.each(initialize);
+
+      function initialize() {
         var $input = $(this),
-            view = new TypeaheadView({ input: $input, datasets: datasets });
+            deferreds,
+            eventBus = new EventBus({ el: $input });
 
-        $input.data('ttView', view);
-      });
+        deferreds = utils.map(datasets, function(dataset) {
+          return dataset.initialize();
+        });
+
+        $input.data(viewKey, new TypeaheadView({
+          input: $input,
+          eventBus: eventBus = new EventBus({ el: $input }),
+          datasets: datasets
+        }));
+
+        $.when.apply($, deferreds)
+        .always(function() { eventBus.trigger('initialized'); });
+      }
     },
 
     destroy: function() {
       this.each(function() {
         var $this = $(this),
-            view = $this.data('ttView');
+            view = $this.data(viewKey);
 
         if (view) {
           view.destroy();
-          $this.removeData('ttView');
+          $this.removeData(viewKey);
         }
       });
     }

src/typeahead_view.js

@@ -66,6 +66,8 @@ var TypeaheadView = (function() {
     this.datasets = o.datasets;
     this.dir = null;
 
+    this.eventBus = o.eventBus;
+
     $menu = this.$node.find('.tt-dropdown-menu');
     $input = this.$node.find('.tt-query');
     $hint = this.$node.find('.tt-hint');
@@ -78,7 +80,8 @@ var TypeaheadView = (function() {
     .on('cursorRemoved', this._updateHint)
     .on('suggestionsRendered', this._updateHint)
     .on('opened', this._updateHint)
-    .on('closed', this._clearHint);
+    .on('closed', this._clearHint)
+    .on('opened closed', this._propagateEvent);
 
     this.inputView = new InputView({ input: $input, hint: $hint })
     .on('focused', this._openDropdown)
@@ -136,8 +139,8 @@ var TypeaheadView = (function() {
     },
 
     _updateHint: function() {
-      var dataForFirstSuggestion = this.dropdownView.getFirstSuggestion(),
-          hint = dataForFirstSuggestion ? dataForFirstSuggestion.value : null,
+      var suggestion = this.dropdownView.getFirstSuggestion(),
+          hint = suggestion ? suggestion.value : null,
           dropdownIsVisible = this.dropdownView.isVisible(),
           inputHasOverflow = this.inputView.isOverflow(),
           inputValue,
@@ -198,11 +201,11 @@ var TypeaheadView = (function() {
 
     _handleSelection: function(e) {
       var byClick = e.type === 'suggestionSelected',
-          suggestionData = byClick ?
+          suggestion = byClick ?
             e.data : this.dropdownView.getSuggestionUnderCursor();
 
-      if (suggestionData) {
-        this.inputView.setInputValue(suggestionData.value);
+      if (suggestion) {
+        this.inputView.setInputValue(suggestion.value);
 
         // if triggered by click, ensure the query input still has focus
         // if triggered by keypress, prevent default browser behavior
@@ -213,6 +216,8 @@ var TypeaheadView = (function() {
         // focus is not a synchronous event in ie, so we deal with it
         byClick && utils.isMsie() ?
           setTimeout(this.dropdownView.close, 0) : this.dropdownView.close();
+
+        this.eventBus.trigger('selected', suggestion);
       }
     },
 
@@ -257,6 +262,10 @@ var TypeaheadView = (function() {
       }
     },
 
+    _propagateEvent: function(e) {
+      this.eventBus.trigger(e.type);
+    },
+
     // public methods
     // --------------