Ticket #2729: itemQuery.patch

ui/ui.sortable.js

@@ -220 +220 @@
             this.items = [];
             this.containers = [this];
             var items = this.items;
-            var queries = [$(this.options.items, this.element)];
+
+      // itemQuery allows us to refine the selection of items used in the sortable.
+      var queries = typeof this.options.itemQuery == 'function' ? 
+        this.options.itemQuery.apply(this) : [$(this.options.items, this.element)];
             
             if(this.options.connectWith) {
                 for (var i = this.options.connectWith.length - 1; i >= 0; i--){

ui/demos/ui.sortable.html

@@ -91 +91 @@
     </ul>
 </div>
 
+<h2>5. Nested lists limited to 1 level deep</h2>
+<div class="playground">
+    <ul id="example5" style="cursor: hand; cursor: pointer;">
+        <li>Drag us</li>
+        <li>around</li>
+        <li>and change
+            <ul>
+                <li>Lorem</li>
+                <li>Ipsum</li>
+            </ul>
+        </li>
+        <li>our</li>
+        <li>positions
+            <ul>
+                <li>Something else</li>
+                <li>Foo bar</li>
+            </ul>
+        </li>
+    </ul>
+</div>
+
 <script type="text/javascript">
 if(!window.console) {
  window.console = {
@@ -110 +131 @@
     $("#example3").sortable({ items: "li", revert: true, tree: true });
     $("#example4").sortable({ placeholder: "hover", revert: true });
 
+    $("#example5").sortable({ 
+    items: "li", revert: true, tree: true,
+    itemQuery: function() {
+      if (this.currentItem) {
+
+        // if list item has a list
+        if ($('ul', this.currentItem).size()) {
+
+          // return only list items from the root list
+          return [$('> li', this.element)];
+        }
+      }
+      return [$(this.options.items, this.element)];
+    }
+  });
+
+
 });
 </script>
 </body>