gecko-dev/editor/libeditor/ChangeStyleTxn.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef ChangeStyleTxn_h__
#define ChangeStyleTxn_h__
#include "EditTxn.h" // base class
#include "nsCOMPtr.h" // nsCOMPtr members
#include "nsCycleCollectionParticipant.h" // various macros
#include "nsString.h" // nsString members
class nsAString;
class nsIAtom;
namespace mozilla {
namespace dom {
class Element;
/**
* A transaction that changes the value of a CSS inline style of a content
* node. This transaction covers add, remove, and change a property's value.
*/
class ChangeStyleTxn : public EditTxn
{
public:
NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(ChangeStyleTxn, EditTxn)
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_EDITTXN
NS_IMETHOD RedoTransaction() MOZ_OVERRIDE;
enum EChangeType { eSet, eRemove };
/** @param aNode [IN] the node whose style attribute will be changed
* @param aProperty [IN] the name of the property to change
* @param aValue [IN] new value for aProperty, or value to remove
* @param aChangeType [IN] whether to set or remove
*/
ChangeStyleTxn(Element& aElement, nsIAtom& aProperty,
const nsAString& aValue, EChangeType aChangeType);
/** Returns true if the list of white-space separated values contains aValue
*
* @return true if the value is in the list of values
* @param aValueList [IN] a list of white-space separated values
* @param aValue [IN] the value to look for in the list
*/
static bool ValueIncludes(const nsAString& aValueList,
const nsAString& aValue);
private:
~ChangeStyleTxn();
/** Adds the value aNewValue to list of white-space separated values aValues
*
* @param aValues [IN/OUT] a list of wite-space separated values
* @param aNewValue [IN] a value this code adds to aValues if it is not already in
*/
void AddValueToMultivalueProperty(nsAString& aValues,
const nsAString& aNewValue);
/** Returns true if the property accepts more than one value
*
* @return true if the property accepts more than one value
* @param aCSSProperty [IN] the CSS property
*/
bool AcceptsMoreThanOneValue(nsIAtom& aCSSProperty);
/** Remove a value from a list of white-space separated values
* @param aValues [IN] a list of white-space separated values
* @param aRemoveValue [IN] the value to remove from the list
*/
void RemoveValueFromListOfValues(nsAString& aValues,
const nsAString& aRemoveValue);
/** If the boolean is true and if the value is not the empty string,
* set the property in the transaction to that value; if the value
* is empty, remove the property from element's styles. If the boolean
* is false, just remove the style attribute.
*/
nsresult SetStyle(bool aAttributeWasSet, nsAString& aValue);
/** The element to operate upon */
nsCOMPtr<Element> mElement;
/** The CSS property to change */
nsCOMPtr<nsIAtom> mProperty;
/** The value to set the property to (ignored if mRemoveProperty==true) */
nsString mValue;
/** true if the operation is to remove mProperty from mElement */
bool mRemoveProperty;
/** The value to set the property to for undo */
nsString mUndoValue;
/** The value to set the property to for redo */
nsString mRedoValue;
/** True if the style attribute was present and not empty before DoTransaction */
bool mUndoAttributeWasSet;
/** True if the style attribute is present and not empty after DoTransaction */
bool mRedoAttributeWasSet;
};
}
}
#endif