CRichEditOleCallback Class

Implements the IRichEditOleCallbackinterface.

The IRichEditOleCallbackinterface is used by a rich text edit control to retrieve OLE-related information from its client. A rich edit control client is responsible for implementing this interface and assigning it to the control by using the EM_SETOLECALLBACK message.

The IRichEditOleCallbackinterface inherits from the IUnknown interface. IRichEditOleCallbackalso has these types of methods:

CRichEditOleCAllback Methods

CONSTRUCTOR

Creates an instance of the CRichEditOleCallback.

CONSTRUCTOR CRichEditOLeCallback

DESTRUCTOR

Called automatically when a class variable goes out of scope or is destroyed.

DESTRUCTOR CRichEditOLeCallback

GetNewStorage

Provides storage for a new object pasted from the clipboard or read in from an Rich Text Format (RTF) stream.

FUNCTION GetNewStorage (BYVAL lplpstg AS LPSTORAGE PTR) AS HRESULT

Return value

Returns S_OK on success. If the method fails, it can return one of the following values.

Remarks

This method must be implemented to allow cut, copy, paste, drag, and drop operations of Component Object Model (COM) objects.

Implementation

FUNCTION CRichEditOleCallback.GetNewStorage (BYVAL lplpstg AS LPSTORAGE PTR) AS HRESULT
   DIM hr AS HRESULT
   DIM pILockBytes AS ILockBytes PTR
   hr = CreateILockBytesOnHGlobal(NULL, TRUE, @pILockBytes)
   IF FAILED(hr) THEN RETURN hr
   hr = StgCreateDocfileOnILockBytes(pILockBytes, _
        STGM_SHARE_EXCLUSIVE OR STGM_READWRITE OR STGM_CREATE, 0, lplpstg)
   RETURN hr
END FUNCTION

GetInPlaceContext

Provides the application and document-level interfaces and information required to support in-place activation.

GetInPlaceContext (BYVAL lplpFrame AS LPOLEINPLACEFRAME PTR, BYVAL lplpDoc AS LPOLEINPLACEUIWINDOW PTR, _
   BYVAL lpFrameInfo AS LPOLEINPLACEFRAMEINFO) AS HRESULT

Return value

Returns S_OK on success. If the method fails, it can return the following value.

ShowContainerUI

Indicates whether or not the application is to display its container UI. The rich edit control looks ahead for double-clicks and defers the call if appropriate. Applications may defer hiding adornments until an IOleInPlaceUIWindow.SetBorderSpace call is received.

FUNCTION ShowContainerUI (BYVAL fShow AS WINBOOL) AS HRESULT

Return value

Returns S_OK on success. If the method fails, it can return the following value.

Remarks

The ShowContainerUI method is called by the IOleInPlaceSite.OnUIActivate and IOleInPlaceSite.OnUIDeactivate methods of the IOleInPlaceSite interface.

QueryInsertObject

Queries the application as to whether an object should be inserted. The member is called when pasting and when reading Rich Text Format (RTF).

FUNCTION QueryInsertObject (BYVAL lpclsid AS LPCLSID, BYVAL lpstg AS LPSTORAGE, BYVAL cp AS LONG) AS HRESULT

Return value

Returns S_OK on success. If the return value is not S_OK, the object was not inserted. If the method fails, it can return the following value.

DeleteObject

Sends notification that an object is about to be deleted from a rich edit control. The object is not necessarily being released when this member is called.

FUNCTION DeleteObject (BYVAL lpoleobj AS LPOLEOBJECT) AS HRESULT

Return value

Returns S_OK.

QueryAcceptData

During a paste operation or a drag event, determines if the data that is pasted or dragged should be accepted.

QueryAcceptData is called when the user attempts to drag or paste an object into the control. If your application can accept the data, your implementation of the method returns S_OK; otherwise, it returns an error code. The method might also take some other action, such as warning the user that files of that type cannot be placed in the control.

FUNCTION QueryAcceptData (BYVAL lpdataobj AS LPDATAOBJECT, BYVAL lpcfFormat AS CLIPFORMAT PTR, _
   BYVAL reco AS DWORD, BYVAL fReally AS WINBOOL, BYVAL hMetaPict AS HGLOBAL) AS HRESULT

Return value

Returns S_OK on success. See Remarks.

Remarks

On failure, the rich edit control refuses the data and terminates the operation. Otherwise, the control checks the data itself for acceptable formats. A success code other than S_OK means that the callback either checked the data itself (if fReally is FALSE) or imported the data itself (if fReally is TRUE). If the application returns a success code other than S_OK, the control does not check the read-only state of the edit control.

ContextSensitiveHelp

Indicates if the application should transition into or out of context-sensitive help mode. This method should implement the functionality described for IOleWindow.ContextSensitiveHelp.

FUNCTION ContextSensitiveHelp (BYVAL fEnterMode AS WINBOOL) AS HRESULT

Return value

Returns S_OK on success. If the method fails, it can return the following value.

GetClipboardData

Allows the client to supply its own clipboard object.

FUNCTION GetClipboardData (BYVAL lpchrg AS CHARRANGE PTR, BYVAL reco AS DWORD, _
   BYVAL lplpdataobj AS LPDATAOBJECT PTR) AS HRESULT

Return value

Returns S_OK on success. If the return value is E_NOTIMPL, the rich edit control created its own clipboard object. If the return value is a failure other than E_NOTIMPL, the operation failed.

GetDragDropEffect

Allows the client to specify the effects of a drop operation.

FUNCTION GetDragDropEffect (BYVAL fDrag AS WINBOOL, BYVAL grfKeyState AS DWORD, _
   BYVAL pdwEffect AS LPDWORD) AS HRESULT

Return value

This method returns S_OK.

GetContextMenu

Queries the application for a context menu to use on a right-click event.

FUNCTION GetContextMenu (BYVAL seltype AS WORD, BYVAL lpoleobj AS LPOLEOBJECT, _
   BYVAL lpchrg AS CHARRANGE PTR, BYVAL lphmenu AS HMENU PTR) AS HRESULT

Returns S_OK on success. If the method fails, it can return the following value.