VividTree - A Colorful and Picturesque Owner Drawn CTreeCtrl Class

• Download demo project - 36.2 Kb
• Download source - 6.7 Kb

Introduction

This owner draw tree control allows for the creation of a tree control loosely resembling the embedded tree in Skype's main window. It demonstrates the basics of creating an owner-drawn tree control, but more importantly, demonstrates gradient backgrounds fills, bitmap backgrounds, flicker free drawing, and how to deal with these in a scrollable and resizable dialog.

Building and Running the Demo Code

Both VC++ 6.0 and VC++ 7.1 project files are included. VC++ 7.1 output directories use the normal Debug/Release directory names. VC+ 6.0 uses VS6_Debug and VS6_Release. The demonstration program has a context (right-click) menu which allows you to change play with some of the different display modes.

Using the code

Importing the code into your project is a fairly easy process. Below are some simple steps to follow:

Step 1: Import the files and resources

Start by simply adding the two source files VividTree.cpp and VividTree.h to your project. Now, add the two bitmap resources (tree_closed.bmp and tree_opened.bmp) and set their resource ID names to IDB_TREE_CLOSED and IDB_TREE_OPENED.

Step 2: Create or change your CTreeCtrl based object

If you already have a CTreeCtrl object, change its declaration to VividTree and include VividTree.h, or create a new CTreeCtrl object and change its declaration to VividTree.

Step 3: Customize the Look

Several customizations are available to change VividTree's look. These class interfaces are shown below:

// BackGround Mode Interfaces 
enum     BkMode { BK_MODE_BMP = 0, BK_MODE_GRADIENT, BK_MODE_FILL };
BkMode   GetBkMode( );
void     SetBkMode( BkMode bkgd_mode );

// Gradient Property Interfaces
void     SetBkGradients( COLORREF from, COLORREF to );
COLORREF GetBkGradientFrom( );
COLORREF GetBkGradientTo( );
bool     GetGradientHorz();
void     SetGradientHorz( bool horz ); // true = horizontal, false = vertical

// Bitmap Background Interfaces
bool     GetBitmapTiledMode();
void     SetBitmapTiledMode( bool tiled );
void     SetBitmapID( UINT id );

// Leaf ICON Setup
virtual void  SetItemIcon( HICON icon );
virtual HICON GetItemIcon( HTREEITEM item );  // Overridable

The left most screenshot graphic (above) mostly shows the default look of VividTree. The one customization done was to add a default icon to the tree leafs (see the code below). Note: the default implementation of GetItemIcon only supports one icon, but GetItemIcon is overridable to allow derived classes to be more prolific in their graphic usage.

m_icon = (HICON)LoadImage( AfxGetApp()->m_hInstance, 
        MAKEINTRESOURCE(IDI_CODE_PROJECT), IMAGE_ICON, 
        16, 16, LR_VGACOLOR );
m_tree.SetItemIcon( m_icon );

In the second screenshot graphic above, a background bitmap is added. The bitmap is stretched to fit the size of the window and re-stretched on a window size change. Below is the initialization code added to achieve this:

m_tree.SetBitmapID( IDB_CODE_PROJECT );
m_tree.SetBkMode( VividTree::BK_MODE_BMP );

In the third screenshot graphic above, VividTree is configured to tile the graphic in the client window. The code to set this mode is:

m_tree.SetBitmapTiledMode( true );

History

Below is the version history for VividTree:

• 9/1/2005 - 1.0.0

  Initial implementation.

Bug Reports

If you have a bug report, or a bug fix, you can contact me through email or with the forums below. I would appreciate a notification of any bugs discovered or improvements that could be made to help the control grow for everyone.

License

This code is provided "as is" with no expressed or implied warranty. You may use, or derive works from this file without any restrictions except those listed below:

• The original code header must be kept in the derived work.
• If your derived work is distributed in any form, you must notify the author and provide a short description of the product and intended audience.
• You may not sell this code or a derived version of it as part of a commercial code library.

Offering the author a free licensed copy of any end product using this code is not required, but does endear you with a bounty of good karma.

Other Code Projects Used by This Project:

• VC++7 to VC++6 project converter

  This tool automatically converts Visual C++ 7.0 projects back to Visual C++ 6.0 projects.