Added better knockout documentation.

Added tests to clarify that selectedOptions is what
 to use when you want to update the checked state of
 multiple options.

index.html

@@ -5375,6 +5375,42 @@ optionLabel: function(element){
                         <dt>How to bind object values using Knockout JS?</dt>
                         <dd>
                           This issue was discussed in <a href="https://github.com/davidstutz/bootstrap-multiselect/issues/532">#532</a>.
+                          <br>
+                          <br>
+                          <p>
+                            bootstrap-multiselect depends upon the following standard knockout bindings:
+                            <br>
+                            <code>options, value, selectedOptions, enable, disable</code>
+                            <br><br>
+                            When these options change, they will update the internal <code>&lt;select&gt;</code> box and then the jQuery multiselect plugin triggers a refresh.
+                          </p>
+                          <ul>
+                            <li><h4>options</h4></li>
+                            <ul>
+                              <li>When options is an observable and changes, your <code>&lt;select&gt;</code> options will be recalculated by knockout, then bootstrap-multiselect will refresh.</li>
+                            </ul>
+                            <li><h4>value</h4></li>
+                            <ul>
+                              <li>Only use this when you are using the radio button feature of bootstrap-multiselect.  Knockout doesn't support using the value binding handler to update <code>&ltselect multiple="multiple"&gt;</code></li>
+                            </ul>
+                            <li><h4>selectedOptions</h4></li>
+                            <ul>
+                              <li>This is a standard knockout binding that updates the checked options inside a select element.  Use this when trying to update a multiple type select box.</li>
+                            </ul>
+                            <li><h4>enable</h4></li>
+                            <ul>
+                              <li>Use it to enable the bootstrap dropdown.</li>
+                            </ul>
+                            <li><h4>disable</h4></li>
+                            <ul>
+                              <li>Use it to enable the bootstrap dropdown.</li>
+                            </ul>
+                          </ul>
+                          <br>
+                          <p>
+                            Any other options inside the multiselect data bind are passed to the jQuery multiselect plugin.
+                          </p>
+                          <br>
                         </dd>
                         
                         <dt>Options do net get updated when using Angular JS?</dt>

tests/SpecRunner.html

@@ -13,9 +13,11 @@
     <script type="text/javascript" src="lib/jasmine-2.0.2/boot.js"></script>
 
     <script type="text/javascript" src="../docs/js/jquery-2.1.3.min.js"></script>
+    <script type="text/javascript" src="http://knockoutjs.com/downloads/knockout-3.4.0.debug.js"></script>
     <script type="text/javascript" src="../docs/js/bootstrap-3.3.2.min.js"></script>
     <script type="text/javascript" src="../dist/js/bootstrap-multiselect.js"></script>
 
+    
     <script type="text/javascript" src="spec/bootstrap-multiselect.js"></script>
 </head>
 

tests/spec/bootstrap-multiselect.js

@@ -705,3 +705,73 @@ describe('Bootstrap Multiselect Specific Issues', function() {
         $selection.remove();
     });
 });
+
+describe('Test knockout binding', function() {
+  var $testArea;
+  afterEach(function() {
+    if ($testArea) {
+      $testArea.multiselect('destroy').remove();
+    }
+  });
+
+  it('should update values and options with an observable array', function() {
+    jasmine.clock().install();
+
+    $testArea = $('<select multiple="multiple" data-bind="selectedOptions: myValues, options: myOptions, multiselect: {numberDisplayed: 1}"></select>').appendTo(document.body);
+    var viewModel = {
+      myValues: ko.observableArray(),
+      myOptions: ko.observableArray([])
+    };
+
+    expect(ko.bindingHandlers.multiselect.init !== undefined).toEqual(true);
+    
+    var optionSpy = spyOn(ko.bindingHandlers.selectedOptions, 'init').and.callThrough(),
+        multiSpy = spyOn(ko.bindingHandlers.multiselect, 'init').and.callThrough();
+
+    ko.applyBindings(viewModel, $testArea[0]);
+
+    // knockout bindings were called
+    expect(optionSpy.calls.count()).toEqual(1);
+    expect(multiSpy.calls.count()).toEqual(1);
+
+    // no options are present since myOptions was empty
+    expect($testArea.find('option').length).toEqual(0);
+    expect($testArea.val()).toEqual(null);
+    
+    expect($testArea.next().find('button.multiselect').text().trim()).toEqual('None selected');
+    expect($testArea.next().find('ul li').length).toEqual(0);
+
+    // Add more options
+    viewModel.myOptions(['option1', 'option2']);
+    jasmine.clock().tick(1000);
+    
+    expect($testArea.next().find('ul li').length).toEqual(2);
+    expect($testArea.find('option').length).toEqual(2);
+    expect($testArea.find('option:checked').length).toEqual(0);
+
+    // select one
+    viewModel.myValues(['option2']);
+    jasmine.clock().tick(1000);
+    
+    expect($testArea.find('option:checked').length).toEqual(1);
+    expect($testArea.find('option:checked').text().trim()).toEqual('option2');
+    
+
+    // select all
+    viewModel.myValues(['option1', 'option2']);
+    jasmine.clock().tick(1000);
+    
+    expect($testArea.find('option:checked').length).toEqual(2);
+    expect($testArea.find('option:checked').map(function() { return $(this).text().trim() }).toArray()).toEqual(['option1', 'option2']);
+    expect($testArea.next().find('button.multiselect').text().trim()).toEqual('All selected (2)');    
+
+    // add another option
+    viewModel.myOptions.push('wacky option');
+    jasmine.clock().tick(1000);
+    
+    expect($testArea.find('option:checked').length).toEqual(2);
+    expect($testArea.find('option:checked').map(function() { return $(this).text().trim() }).toArray()).toEqual(['option1', 'option2']);
+    expect($testArea.find('option').map(function() { return $(this).text().trim() }).toArray()).toEqual(['option1', 'option2', 'wacky option']);
+    expect($testArea.next().find('button.multiselect').text().trim()).toEqual('2 selected');    
+  });
+});