editor/libeditor/ChangeAttributeTransaction.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef ChangeAttributeTransaction_h
   7 #define ChangeAttributeTransaction_h
   8
   9 #include "EditTransactionBase.h"  // base class
  10
  11 #include "mozilla/Attributes.h"            // override
  12 #include "nsCOMPtr.h"                      // nsCOMPtr members
  13 #include "nsCycleCollectionParticipant.h"  // NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED
  14 #include "nsISupportsImpl.h"               // NS_DECL_ISUPPORTS_INHERITED
  15 #include "nsString.h"                      // nsString members
  16
  17 class nsAtom;
  18
  19 namespace mozilla {
  20 namespace dom {
  21 class Element;
  22 }  // namespace dom
  23
  24 /**
  25  * A transaction that changes an attribute of a content node.  This transaction
  26  * covers add, remove, and change attribute.
  27  */
  28 class ChangeAttributeTransaction final : public EditTransactionBase {
  29  protected:
  30   ChangeAttributeTransaction(dom::Element& aElement, nsAtom& aAttribute,
  31                              const nsAString* aValue);
  32
  33  public:
  34   /**
  35    * Creates a change attribute transaction to set an attribute to something.
  36    * This method never returns nullptr.
  37    *
  38    * @param aElement    The element whose attribute will be changed.
  39    * @param aAttribute  The name of the attribute to change.
  40    * @param aValue      The new value for aAttribute.
  41    */
  42   static already_AddRefed<ChangeAttributeTransaction> Create(
  43       dom::Element& aElement, nsAtom& aAttribute, const nsAString& aValue);
  44
  45   /**
  46    * Creates a change attribute transaction to remove an attribute.  This
  47    * method never returns nullptr.
  48    *
  49    * @param aElement    The element whose attribute will be changed.
  50    * @param aAttribute  The name of the attribute to remove.
  51    */
  52   static already_AddRefed<ChangeAttributeTransaction> CreateToRemove(
  53       dom::Element& aElement, nsAtom& aAttribute);
  54
  55   NS_DECL_ISUPPORTS_INHERITED
  56   NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(ChangeAttributeTransaction,
  57                                            EditTransactionBase)
  58
  59   NS_DECL_EDITTRANSACTIONBASE
  60   NS_DECL_EDITTRANSACTIONBASE_GETASMETHODS_OVERRIDE(ChangeAttributeTransaction)
  61
  62   MOZ_CAN_RUN_SCRIPT NS_IMETHOD RedoTransaction() override;
  63
  64   friend std::ostream& operator<<(
  65       std::ostream& aStream, const ChangeAttributeTransaction& aTransaction);
  66
  67  private:
  68   virtual ~ChangeAttributeTransaction() = default;
  69
  70   // The element to operate upon
  71   nsCOMPtr<dom::Element> mElement;
  72
  73   // The attribute to change
  74   RefPtr<nsAtom> mAttribute;
  75
  76   // The value to set the attribute to (ignored if mRemoveAttribute==true)
  77   nsString mValue;
  78
  79   // The value to set the attribute to for undo
  80   nsString mUndoValue;
  81
  82   // True if the operation is to remove mAttribute from mElement
  83   bool mRemoveAttribute;
  84
  85   // True if the mAttribute was set on mElement at the time of execution
  86   bool mAttributeWasSet;
  87 };
  88
  89 }  // namespace mozilla
  90
  91 #endif  // #ifndef ChangeAttributeTransaction_h