A multi-select tree control class

Sample Image

Environment: VC6 SP2

There have already been several implementations of a multi-select tree control posted to CodeGuru, but none of them have provided the functionality and/or behaviour I required.

The versions I have seen take the approach of handling the selection around the mouse-down, mouse-move and mouse-up messages, with variables holding state in-between. CMultiTree takes the approach of handling the whole multi-selection within the mouse-down handler. This is a closer approach to the underlying Windows treeview control.

CMultiTree attempts to mirror the selection behaviour of a CListCtrl (listview control) class. In fact the code was developed by putting a CListCtrl next to a CTreeCtrl and trying the combinations of mouse clicks/drags, and key presses. CMultiTree thus has full rubber-band selection support.

The sample application implements the CTreeCtrl in a CTreeView class, using a method described on a CodeGuru site. Unfortunately I can't find the original article to credit the author [hopefully the editor can do this on my behalf].

Usage

Multiple-selection in CMultiTree should be done in more or less the same way as in a CListCtrl, i.e. using SetItemState, GetItemState. I have taken the liberty of defining a TVIS_FOCUSED (the equivalent of LVIS_FOCUSED of the CListCtrl).

SetItemState / GetItemState:

These two methods have been over-scoped in the CMultiTree class to replace the underlying CTreeCtrl versions. Because they are NOT virtual, they must be called in the scope of the CMultiTree class (or derived class), otherwise they will not work, e.g.:


    /* if m_tree is a CMultiTree */
    CTreeCtrl *pTree = &m_tree;
    UINT nState = pTree->GetItemState(hItem, TVIS_FOCUSED|TVIS_SELECTED);

this will NOT call the CMultiTree version because of the non-virtual GetItemState.

Examine the header file for other methods, they are pretty self-explanatory.

Comments: mailto:comments@tinuviel.demon.co.uk
Info: http://www.tinuviel.demon.co.uk/source_code/sc_multitree.htm
Copyright (c) 1999 Richard Hazlewood.

Downloads

Download demo project - 34 Kb



Comments

  • Not working

    Posted by Liviu Dorobantu on 04/10/2014 08:54am

    Hello! I integrated your code for multiple selection on a CTreeCtrl taken from here:http://www.codeguru.com/cpp/controls/treeview/misc-advanced/article.php/c629/A-multiselect-tree-control-class.htm. The problem is that multi selection with Ctrl does not work (the program runs). I'm using Visual Studio 2005. If I run your program as downloaded from the link above, it works, but not if I take MltiTree.h and MltiTree.cpp and put them in my program. Do you have any ideea? Thanks!

    Reply
Leave a Comment
  • Your email address will not be published. All fields are required.

Top White Papers and Webcasts

  • IT is rapidly moving to a more dynamic, services-based model in response to businesses' growing demand for faster creation and delivery of services to end customers. A consequence of this move is the emergence of hybrid IT organizations that can improve on-site data center asset utilization while leveraging cloud-based assets to extend services and capabilities. IDC asserts that controlling data flow in a hybrid IT environment is crucial for businesses to effectively transform themselves into data-driven …

  • On-demand Event Event Date: July 22, 2015 Today's increasingly mobile workforce creates new challenges for organizations that rely heavily on collaboration. Businesses need to be both secure and collaborative, and they can't sacrifice one over the other. The plethora of devices and clouds used by mobile employees only complicates these challenges. Watch this webcast and learn how your business can enable mobile access to files from anywhere while it helps to maintain information governance, compliance, and …

Most Popular Programming Stories

More for Developers

RSS Feeds

Thanks for your registration, follow us on our social networks to keep up-to-date