add bootstrap-scrollspy

js/bootstrap-scrollspy.js

@@ -0,0 +1,88 @@
+/* =============================================================
+ * bootstrap-scrollspy.js
+ * http://twitter.github.com/bootstrap/javascript.html#scrollspy
+ * =============================================================
+ * Copyright 2011 Twitter, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ==============================================================
+ */
+
+!function ( $ ) {
+
+  var $window = $(window)
+
+  function ScrollSpy( topbar ) {
+    var processScroll = $.proxy(this.processScroll, this)
+    this.$topbar = $(topbar)
+    this.setup()
+    this.$topbar
+      .delegate('li > a', 'click', processScroll)
+      .bind('topbar:refresh', $.proxy(this.setup, this))
+    $window.scroll(processScroll)
+    this.processScroll()
+  }
+
+  ScrollSpy.prototype = {
+
+      setup: function () {
+        this.targets = this.$topbar.find('li > a').map(function () {
+          var href = $(this).attr('href')
+          return /^#\w/.test(href) && $(href).length ? href : null
+        })
+
+        this.offsets = $.map(this.targets, function (id) {
+          return $(id).offset().top
+        })
+      }
+
+    , processScroll: function () {
+        var scrollTop = $window.scrollTop() + 10
+          , offsets = this.offsets
+          , targets = this.targets
+          , activeTarget = this.activeTarget
+          , i
+
+        for (i = offsets.length; i--;) {
+          activeTarget != targets[i]
+            && scrollTop >= offsets[i]
+            && (!offsets[i + 1] || scrollTop <= offsets[i + 1])
+            && this.activateButton( targets[i] )
+        }
+      }
+
+    , activateButton: function (target) {
+        this.activeTarget = target
+
+        this.$topbar
+          .find('.active')
+          .removeClass('active')
+
+        this.$topbar
+          .find('a[href=' + target + ']')
+          .parent('li')
+          .addClass('active')
+      }
+
+  }
+
+  /* SCROLLSPY PLUGIN DEFINITION
+   * =========================== */
+
+  $.fn.scrollSpy = function() {
+    return this.each(function () {
+      new ScrollSpy(this)
+    })
+  }
+
+}( jQuery || ender )