* nsIEditor is the base interface used by applications to communicate with the editor.
* It makes no assumptions about the kind of content it is editing,
* other than the content being a DOM tree.
*/
class nsIEditor : public nsISupports{
public:
typedef enum {NONE = 0,BOLD = 1,NUMPROPERTIES} Properties;
typedef enum {eLTR=0, eRTL=1} Direction;
static const nsIID& IID() { static nsIID iid = NS_IEDITOR_IID; return iid; }
/**
* Init tells is to tell the implementation of nsIEditor to begin its services
* @param aDomInterface The dom interface being observed
* @param aPresShell TEMP: The presentation shell displaying the document
* once events can tell us from what pres shell they originated,
* this will no longer be necessary and the editor will no longer be
* linked to a single pres shell.
*/
virtual nsresult Init(nsIDOMDocument *aDomInterface,
nsIPresShell *aPresShell) = 0;
/**
* return the DOM Document this editor is associated with
*
* @param aDoc [OUT] the dom interface being observed, refcounted
*/
virtual nsresult GetDocument(nsIDOMDocument **aDoc)=0;
/**
* SetProperties() sets the aggregate properties on the current selection
*
* @param aProperty An enum that lists the various properties that can be applied, bold, ect.
* @see Properties
* NOTE: this is an experimental interface. Since it's really just a shortcut for
* the caller setting a set of attributes on a set of nodes, this method may be removed.
* If it's more than just a convenience method (ie, it has logic about what objects in a selection get
* which attributes) that's a whole other story.
*/
virtual nsresult SetProperties(Properties aProperties)=0;
/**
* GetProperties() gets the aggregate properties of the current selection.
* All object in the current selection are scanned and their attributes are
* represented in a list of Property object.
*
* @param aProperty An enum that will recieve the various properties that can be applied from the current selection.
* @see nsIEditor::Properties
* NOTE: this method is experimental, expect it to change.
*/
virtual nsresult GetProperties(Properties **aProperties)=0;
/**
* SetAttribute() sets the attribute of aElement.
* No checking is done to see if aAttribute is a legal attribute of the node,
* or if aValue is a legal value of aAttribute.
*
* @param aElement the content element to operate on
* @param aAttribute the string representation of the attribute to set
* @param aValue the value to set aAttribute to
*/
virtual nsresult SetAttribute(nsIDOMElement * aElement,
const nsString& aAttribute,
const nsString& aValue)=0;
/**
* GetAttributeValue() retrieves the attribute's value for aElement.
*
* @param aElement the content element to operate on
* @param aAttribute the string representation of the attribute to get
* @param aResultValue the value of aAttribute. only valid if aResultIsSet is PR_TRUE
* @param aResultIsSet PR_TRUE if aAttribute is set on the current node, PR_FALSE if it is not.
*/
virtual nsresult GetAttributeValue(nsIDOMElement * aElement,
const nsString& aAttribute,
nsString& aResultValue,
PRBool& aResultIsSet)=0;
/**
* RemoveAttribute() deletes aAttribute from the attribute list of aElement.
* If aAttribute is not an attribute of aElement, nothing is done.
*
* @param aElement the content element to operate on
* @param aAttribute the string representation of the attribute to get
*/
virtual nsresult RemoveAttribute(nsIDOMElement * aElement,
const nsString& aAttribute)=0;
/**
* CreateElement instantiates a new element of type aTag and inserts it into aParent at aPosition.
* @param aTag The type of object to create
* @param aParent The node to insert the new object into
* @param aPosition The place in aParent to insert the new node
*/
virtual nsresult CreateElement(const nsString& aTag,
nsIDOMNode * aParent,
PRInt32 aPosition)=0;
/**
* DeleteElement removes aChild from aParent.
* If aChild is not a child of aParent, nothing is done and an error is returned.
* @param aChild The node to delete
* @param aParent The parent of aChild
*/
virtual nsresult DeleteElement(nsIDOMNode * aParent,
nsIDOMNode * aChild)=0;
/**
* DeleteSelection removes all nodes in the current selection.
* @param aDir if eLTR, delete to the right (for example, the DEL key)
* if eRTL, delete to the left (for example, the BACKSPACE key)
*/
virtual nsresult DeleteSelection(nsIEditor::Direction aDir)=0;
/**
* SplitNode() creates a new node identical to an existing node, and split the contents between the two nodes
* @param aExistingRightNode the node to split. It will become the new node's next sibling.
* @param aOffset the offset of aExistingRightNode's content|children to do the split at
* @param aNewLeftNode [OUT] the new node resulting from the split, becomes aExistingRightNode's previous sibling.
* @param aParent the parent of aExistingRightNode
*/
virtual nsresult SplitNode(nsIDOMNode * aExistingRightNode,
PRInt32 aOffset,
nsIDOMNode * aNewLeftNode,
nsIDOMNode * aParent)=0;
/**
* JoinNodes() takes 2 nodes and merge their content|children.
* @param aNodeToKeep The node that will remain after the join.
* @param aNodeToJoin The node that will be joined with aNodeToKeep.
* There is no requirement that the two nodes be of the same type.
* @param aParent The parent of aExistingRightNode
* @param aNodeToKeepIsFirst if PR_TRUE, the contents|children of aNodeToKeep come before the
* contents|children of aNodeToJoin, otherwise their positions are switched.
*/
virtual nsresult JoinNodes(nsIDOMNode *aNodeToKeep,
nsIDOMNode *aNodeToJoin,
nsIDOMNode *aParent,
PRBool aNodeToKeepIsFirst)=0;
/**
* InsertText() Inserts a string at the current location, given by the selection.
* If the selection is not collapsed, the selection is deleted and the insertion
* takes place at the resulting collapsed selection.
*
* NOTE: what happens if the string contains a CR?
*
* @param aString the string to be inserted
*/
virtual nsresult InsertText(const nsString& aStringToInsert)=0;
/**
* Commit(PRBool aCtrlKey) is a catch all method. It may be depricated later.
*
It is to respond to RETURN keys and CTRL return keys. Its action depends
* on the selection at the time. It may insert a
or a
or activate the properties of the element * @param aCtrlKey was the CtrlKey down? */ virtual nsresult Commit(PRBool aCtrlKey)=0; /** turn the undo system on or off * @param aEnable if PR_TRUE, the undo system is turned on if it is available * if PR_FALSE the undo system is turned off if it was previously on * @return if aEnable is PR_TRUE, returns NS_OK if the undo system could be initialized properly * if aEnable is PR_FALSE, returns NS_OK. */ virtual nsresult EnableUndo(PRBool aEnable)=0; /** Do() fires a transaction. It is provided here so clients can create their own transactions. * If a transaction manager is present, it is used. * Otherwise, the transaction is just executed directly. * * @param aTxn the transaction to execute */ virtual nsresult Do(nsITransaction *aTxn)=0; /** Undo reverses the effects of the last Do operation, if Undo is enabled in the editor. * It is provided here so clients need no knowledge of whether the editor has a transaction manager or not. * If a transaction manager is present, it is told to undo and the result of * that undo is returned. * Otherwise, the Undo request is ignored and an error NS_ERROR_NOT_AVAILABLE is returned. * */ virtual nsresult Undo(PRUint32 aCount)=0; /** returns state information about the undo system. * @param aIsEnabled [OUT] PR_TRUE if undo is enabled * @param aCanUndo [OUT] PR_TRUE if at least one transaction is currently ready to be undone. */ virtual nsresult CanUndo(PRBool &aIsEnabled, PRBool &aCanUndo)=0; /** Redo reverses the effects of the last Undo operation * It is provided here so clients need no knowledge of whether the editor has a transaction manager or not. * If a transaction manager is present, it is told to redo and the result of the previously undone * transaction is reapplied to the document. * If no transaction is available for Redo, or if the document has no transaction manager, * the Redo request is ignored and an error NS_ERROR_NOT_AVAILABLE is returned. * */ virtual nsresult Redo(PRUint32 aCount)=0; /** returns state information about the redo system. * @param aIsEnabled [OUT] PR_TRUE if redo is enabled * @param aCanRedo [OUT] PR_TRUE if at least one transaction is currently ready to be redone. */ virtual nsresult CanRedo(PRBool &aIsEnabled, PRBool &aCanRedo)=0; /** BeginUpdate is a signal from the caller to the editor that the caller will execute multiple updates * to the content tree that should be treated in the most efficient way possible. * All transactions executed between a call to BeginUpdate and EndUpdate will be undoable as * an atomic action. * EndUpdate must be called after BeginUpdate. * Calls to BeginUpdate can be nested, as long as EndUpdate is called once per BeginUpdate. */ virtual nsresult BeginUpdate()=0; /** EndUpdate is a signal to the editor that the caller is finished updating the content model. * BeginUpdate must be called before EndUpdate is called. * Calls to BeginUpdate can be nested, as long as EndUpdate is called once per BeginUpdate. */ virtual nsresult EndUpdate()=0; }; #endif //nsIEditor_h__