Settings for the Toolbar Control
The buttons on a toolbar can display a bitmap, a string, or both. By default, the image size is set to the dimensions of 16 by 15 pixels. All buttons are the same width, by default 24 by 22 pixels. A toolbar's height is determined by the height of the buttons, and a toolbar's width is the same as the width of the parent window's client area, also by default.
A toolbar can have built-in customization features, including a system-defined customization dialog box, that allow the user to insert, delete, or rearrange toolbar buttons. An application determines whether the customization features are available to the user and controls the extent to which the user can customize the toolbar. For more information about customizing the toolbar, see class CToolBarCtrl in the MFC Reference.