editor/libeditor/ChangeAttributeTxn.cpp

   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 #include "ChangeAttributeTxn.h"
   7
   8 #include "mozilla/dom/Element.h"        // for Element
   9
  10 #include "nsAString.h"
  11 #include "nsError.h"                    // for NS_ERROR_NOT_INITIALIZED, etc
  12
  13 using namespace mozilla;
  14 using namespace mozilla::dom;
  15
  16 ChangeAttributeTxn::ChangeAttributeTxn(Element& aElement, nsIAtom& aAttribute,
  17                                        const nsAString* aValue)
  18   : EditTxn()
  19   , mElement(&aElement)
  20   , mAttribute(&aAttribute)
  21   , mValue(aValue ? *aValue : EmptyString())
  22   , mRemoveAttribute(!aValue)
  23   , mAttributeWasSet(false)
  24   , mUndoValue()
  25 {
  26 }
  27
  28 ChangeAttributeTxn::~ChangeAttributeTxn()
  29 {
  30 }
  31
  32 NS_IMPL_CYCLE_COLLECTION_INHERITED(ChangeAttributeTxn, EditTxn,
  33                                    mElement)
  34
  35 NS_IMPL_ADDREF_INHERITED(ChangeAttributeTxn, EditTxn)
  36 NS_IMPL_RELEASE_INHERITED(ChangeAttributeTxn, EditTxn)
  37 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ChangeAttributeTxn)
  38 NS_INTERFACE_MAP_END_INHERITING(EditTxn)
  39
  40 NS_IMETHODIMP
  41 ChangeAttributeTxn::DoTransaction()
  42 {
  43   // Need to get the current value of the attribute and save it, and set
  44   // mAttributeWasSet
  45   mAttributeWasSet = mElement->GetAttr(kNameSpaceID_None, mAttribute,
  46                                        mUndoValue);
  47
  48   // XXX: hack until attribute-was-set code is implemented
  49   if (!mUndoValue.IsEmpty()) {
  50     mAttributeWasSet = true;
  51   }
  52   // XXX: end hack
  53
  54   // Now set the attribute to the new value
  55   if (mRemoveAttribute) {
  56     return mElement->UnsetAttr(kNameSpaceID_None, mAttribute, true);
  57   }
  58
  59   return mElement->SetAttr(kNameSpaceID_None, mAttribute, mValue, true);
  60 }
  61
  62 NS_IMETHODIMP
  63 ChangeAttributeTxn::UndoTransaction()
  64 {
  65   if (mAttributeWasSet) {
  66     return mElement->SetAttr(kNameSpaceID_None, mAttribute, mUndoValue, true);
  67   }
  68   return mElement->UnsetAttr(kNameSpaceID_None, mAttribute, true);
  69 }
  70
  71 NS_IMETHODIMP
  72 ChangeAttributeTxn::RedoTransaction()
  73 {
  74   if (mRemoveAttribute) {
  75     return mElement->UnsetAttr(kNameSpaceID_None, mAttribute, true);
  76   }
  77
  78   return mElement->SetAttr(kNameSpaceID_None, mAttribute, mValue, true);
  79 }
  80
  81 NS_IMETHODIMP
  82 ChangeAttributeTxn::GetTxnDescription(nsAString& aString)
  83 {
  84   aString.AssignLiteral("ChangeAttributeTxn: [mRemoveAttribute == ");
  85
  86   if (mRemoveAttribute) {
  87     aString.AppendLiteral("true] ");
  88   } else {
  89     aString.AppendLiteral("false] ");
  90   }
  91   aString += nsDependentAtomString(mAttribute);
  92   return NS_OK;
  93 }