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Moving an item or a branch is a combination of copying followed by deleting. To move an item use CopyItem() followed by DeleteItem(). To move a branch use CopyBranch() followed by DeleteItem(). Note that when you delete an item then any child item is also deleted.  

To escape out of a drag and drop operation we can look for the ESCAPE key in the PreTranslateMessage() and terminate the operation without moving any item..   BOOL CTreeCtrlX::PreTranslateMessage(MSG* pMsg) { if( pMsg->message == WM_KEYDOWN && pMsg->wParam == VK_ESCAPE  && m_bLDragging) { m_bLDragging = 0; CImageList::DragLeave(NULL); CImageList::EndDrag(); ReleaseCapture(); SelectDropTarget(NULL); delete m_pDragImage; return TRUE; // […]

Have you ever noticed how, when you drag an item from the left pane in the Explorer, the drag image is always created relative to the cursor position? It looks like you are grabbing the drag item exactly where the cursor is. Here is code that accomplishes this. The key is to dynamically calculate the […]

“An operation in which the end user uses the mouse or other pointing device to move data to another location in the same window or another window”. This is right off the glossary in the VC++ help files. Note that this statement says move data but drag and drop is commonly understood to encompass copy […]

When dragging an item it is quite possible that the drop target is not visible. Sometimes the user can collapse some items so that both the item to be dragged and the item that is to be the drop target are both visible. However, the user doesnt always have this recourse. Besides, most professional apps […]

I modified the code for using drag & drop on tree controls. The idea was to add three features found on the ClassView tree control of the VC++ ide. With the following code you can disable the drag & drop interface for certain items on the tree (the root item in ClassView, for example), and […]

Copying an item is simple but Ive listed a function for copying anyway. This function is used by other functions discussed later and it also contains a component that we often forget – extensibility. At the end of the function, the OnItemCopied() function is called to give the derived class the oppurtunity to update any […]

I wrote a base class from which the MFC users can derive their TreeView classes in a document-view based application instead of CTreeView. This class adds to CtreeView build-in drag-and-drop support. All that the developer have to do is to add this class to the AppWizard generated project (with CTreeView as a View base class) […]

I realized a lot of developers are interested in code for printing CTreectrl. I was in the same situation and tried a lot of different ways, but every approach had its disadvantage. The simplest solution seemed in the call of CWnd::Print(…), but this only prints the visible part of the control, which was not what […]

CLongOperation is a class designed to give visual feedback for long-lasting operations. It has support for: Displaying a wait cursor Showing a text in the status bar Displaying a progress bar in a dynamically created status bar pane In the simplest case, this class can be used as a replacement for MFC’s CWaitCursor: CLongOperation wait; […]

This simple trick uses string pointer manipulation to give scrolling effect in a status bar. The code is not robust. It only demonstrates how it could be done. 1. Derive your own CMyStatusBar from CstatusBar. 2. In MainFrm.h, change the type of status bar as: CMyStatusBar m_wndStatusBar; 3. Also change the indicator array in MainFrm.cpp […]

Displays horizontally scrolling text, vertically scrolling text, changing fonts for each status bar pane, changing font colors for each status bar pane, changing background colors for each status bar pane, displaying a bitmap banner across the status bar. I was recently involved in a project that required colors along the status bar (basically, an owner-drawn […]