Aggregate CSS manipulation functions in html lib.

sdk/lib/html/dart2js/html_dart2js.dart

 /// The Dart HTML library.
 library dart.dom.html;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:_collection-dev';
 import 'dart:html_common';
 import 'dart:indexed_db';
 import 'dart:isolate';
 import 'dart:json' as json;
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    * Unless your webpage contains multiple documents, the top-level queryAll
    * method behaves the same as this method, so you should use it instead to
    * save typing a few characters.
    *
    * [selectors] should be a string using CSS selector syntax.
    *     var items = document.queryAll('.itemClassName');
    *
    * For details about CSS selector syntax, see the
    * [CSS selector specification](http://www.w3.org/TR/css3-selectors/).
    */
-  List<Element> queryAll(String selectors) {
-    return new _FrozenElementList._wrap($dom_querySelectorAll(selectors));
+  HtmlList<Element> queryAll(String selectors) {
+    return new HtmlList._wrap($dom_querySelectorAll(selectors));
   }
 }
 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 
 @DomName('DocumentFragment')
 class DocumentFragment extends Node native "DocumentFragment" {
   factory DocumentFragment() => _DocumentFragmentFactoryProvider.createDocumentFragment();
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   Element get single {
     if (length > 1) throw new StateError("More than one element");
     return first;
   }
 }
 
 // TODO(jacobr): this is an inefficient implementation but it is hard to see
 // a better option given that we cannot quite force NodeList to be an
 // ElementList as there are valid cases where a NodeList JavaScript object
 // contains Node objects that are not Elements.
-class _FrozenElementList<T extends Element> extends ListBase<T> {
+/** 
+ * An immutable list containing HTML elements. This list contains some
+ * additional methods for ease of CSS manipulation on a group of elements.
+ */
+class HtmlList<T extends Element> extends ListBase<T> {
   final List<Node> _nodeList;
 
-  _FrozenElementList._wrap(this._nodeList);
+  HtmlList._wrap(this._nodeList);
 
   int get length => _nodeList.length;
 
   Element operator [](int index) => _nodeList[index];
 
   void operator []=(int index, Element value) {
     throw new UnsupportedError('Cannot modify list');
   }
 
   void set length(int newLength) {
     throw new UnsupportedError('Cannot modify list');
   }
 
   void sort([Comparator<Element> compare]) {
     throw new UnsupportedError('Cannot sort list');
   }
 
   Element get first => _nodeList.first;
 
   Element get last => _nodeList.last;
 
   Element get single => _nodeList.single;
+
+  /**
+   * The union of all CSS classes applied to the elements in this list.
+   *
+   * This set makes it easy to add, remove or toggle (add if not present, remove
+   * if present) the classes applied to a collection of elements.
+   *
+   *     htmlList.classes.add('selected');
+   *     htmlList.classes.toggle('isOnline');
+   *     htmlList.classes.remove('selected');
+   */
+  CssClassSet get classes => new _MultiElementCssClassSet(
+      _nodeList.where((e) => e is Element));
+
+  /** Replace the classes with `value` for every element in this list. */
+  void set classes(Iterable<String> value) {
+    _nodeList.where((e) => e is Element).forEach((e) { 
+        e.classes.clear();
+        e.classes.addAll(value); 
+      });
+  }
+}
+
+/**
+ * A set (union) of the CSS classes that are present in a set of elements.
+ * Implemented separately from _ElementCssClassSet for performance.
+ */
+class _MultiElementCssClassSet extends CssClassSet {
+  final Iterable<Element> _elementIterable;
+  Iterable<_ElementCssClassSet> _elementCssClassSetIterable;
+
+  _MultiElementCssClassSet(this._elementIterable) {
+    _elementCssClassSetIterable = new List.from(_elementIterable).map(
+        (e) => new _ElementCssClassSet(e));
+  }
+
+  Set<String> readClasses() {
+    var s = new LinkedHashSet<String>();
+    _elementCssClassSetIterable.forEach((e) => s.addAll(e.readClasses()));
+    return s;
+  }
+
+  void writeClasses(Set<String> s) {
+    var classes = new List.from(s).join(' ');
+    for (Element e in _elementIterable) {
+      e.$dom_className = classes;
+    }
+  }
+
+  /**
+   * Helper method used to modify the set of css classes on this element.
+   *
+   *   f - callback with:
+   *   s - a Set of all the css class name currently on this element.
+   *
+   *   After f returns, the modified set is written to the
+   *       className property of this element.
+   */
+  void modify( f(Set<String> s)) {
+    _elementCssClassSetIterable.forEach((e) => e.modify(f));
+  }
+
+  /**
+   * Adds the class [value] to the element if it is not on it, removes it if it
+   * is.
+   */
+  bool toggle(String value) => 
+      _modifyWithReturnValue((e) => e.toggle(value));
+  
+  /**
+   * Remove the class [value] from element, and return true on successful
+   * removal.
+   *
+   * This is the Dart equivalent of jQuery's
+   * [removeClass](http://api.jquery.com/removeClass/).
+   */
+  bool remove(Object value) => _modifyWithReturnValue((e) => e.remove(value));
+
+  bool _modifyWithReturnValue(f) => _elementCssClassSetIterable.fold(
+      false, (prevValue, element) => f(element) || prevValue);
 }
 
 class _ElementCssClassSet extends CssClassSet {
 
   final Element _element;
 
   _ElementCssClassSet(this._element);
 
   Set<String> readClasses() {
     var s = new LinkedHashSet<String>();
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   }
 
   /**
    * Finds all descendent elements of this element that match the specified
    * group of selectors.
    *
    * [selectors] should be a string using CSS selector syntax.
    *
    *     var items = element.query('.itemClassName');
    */
-  List<Element> queryAll(String selectors) =>
-    new _FrozenElementList._wrap($dom_querySelectorAll(selectors));
+  HtmlList<Element> queryAll(String selectors) =>
+    new HtmlList._wrap($dom_querySelectorAll(selectors));
 
   /**
    * The set of CSS classes applied to this element.
    *
    * This set makes it easy to add, remove or toggle the classes applied to
    * this element.
    *
    *     element.classes.add('selected');
    *     element.classes.toggle('isOnline');
    *     element.classes.remove('selected');
@@ skipping 18462 matching lines @@
 
   /**
    * Add the class [value] to element.
    *
    * This is the Dart equivalent of jQuery's
    * [addClass](http://api.jquery.com/addClass/).
    */
   void add(String value) {
     // TODO - figure out if we need to do any validation here
     // or if the browser natively does enough.
-    _modify((s) => s.add(value));
+    modify((s) => s.add(value));
   }
 
   /**
    * Remove the class [value] from element, and return true on successful
    * removal.
    *
    * This is the Dart equivalent of jQuery's
    * [removeClass](http://api.jquery.com/removeClass/).
    */
   bool remove(Object value) {
     if (value is! String) return false;
     Set<String> s = readClasses();
     bool result = s.remove(value);
     writeClasses(s);
     return result;
   }
 
   /**
    * Add all classes specified in [iterable] to element.
    *
    * This is the Dart equivalent of jQuery's
    * [addClass](http://api.jquery.com/addClass/).
    */
   void addAll(Iterable<String> iterable) {
     // TODO - see comment above about validation.
-    _modify((s) => s.addAll(iterable));
+    modify((s) => s.addAll(iterable));
   }
 
   /**
    * Remove all classes specified in [iterable] from element.
    *
    * This is the Dart equivalent of jQuery's
    * [removeClass](http://api.jquery.com/removeClass/).
    */
   void removeAll(Iterable<String> iterable) {
-    _modify((s) => s.removeAll(iterable));
+    modify((s) => s.removeAll(iterable));
   }
 
   /**
    * Toggles all classes specified in [iterable] on element.
    *
    * Iterate through [iterable]'s items, and add it if it is not on it, or
    * remove it if it is. This is the Dart equivalent of jQuery's
    * [toggleClass](http://api.jquery.com/toggleClass/).
    */
   void toggleAll(Iterable<String> iterable) {
     iterable.forEach(toggle);
   }
 
   void retainAll(Iterable<String> iterable) {
-    _modify((s) => s.retainAll(iterable));
+    modify((s) => s.retainAll(iterable));
   }
 
   void removeWhere(bool test(String name)) {
-    _modify((s) => s.removeWhere(test));
+    modify((s) => s.removeWhere(test));
   }
 
   void retainWhere(bool test(String name)) {
-    _modify((s) => s.retainWhere(test));
+    modify((s) => s.retainWhere(test));
   }
 
   bool containsAll(Iterable<String> collection) =>
     readClasses().containsAll(collection);
 
   Set<String> intersection(Set<String> other) =>
     readClasses().intersection(other);
 
   Set<String> union(Set<String> other) =>
     readClasses().union(other);
@@ skipping 15 matching lines @@
       readClasses().skipWhile(test);
   String firstWhere(bool test(String value), { String orElse() }) =>
       readClasses().firstWhere(test, orElse: orElse);
   String lastWhere(bool test(String value), {String orElse()}) =>
       readClasses().lastWhere(test, orElse: orElse);
   String singleWhere(bool test(String value)) =>
       readClasses().singleWhere(test);
   String elementAt(int index) => readClasses().elementAt(index);
 
   void clear() {
-    _modify((s) => s.clear());
+    modify((s) => s.clear());
   }
   // interface Set - END
 
   /**
    * Helper method used to modify the set of css classes on this element.
    *
    *   f - callback with:
    *   s - a Set of all the css class name currently on this element.
    *
    *   After f returns, the modified set is written to the
    *       className property of this element.
    */
-  void _modify( f(Set<String> s)) {
+  void modify( f(Set<String> s)) {
     Set<String> s = readClasses();
     f(s);
     writeClasses(s);
   }
 
   /**
    * Read the class names from the Element class property,
    * and put them into a set (duplicates are discarded).
    * This is intended to be overridden by specific implementations.
    */
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       _position = nextPosition;
       return true;
     }
     _current = null;
     _position = _array.length;
     return false;
   }
 
   T get current => _current;
 }