Advanced MFC Programming

Chapter 5. Common Controls
Changing List Style Dynamically
The style of the list control can be set in property sheet “List control properties” before the application
is compiled(see Figure 5-14). But, sometimes we may want to provide the user with the power of changing
this style dynamically. When the program is running, we can call API function ::SetWindwoLong(…) to
change the application’s style. For list control, we can choose from one of the following styles: LVS_ICON,
LVS_SMALLICON, LVS_LIST and LVS_REPORT.
Select one of the
styles
Figure 5-14. Set the style for list control
In the sample, four radio buttons are added to the dialog template for selecting different styles. Their
IDs are IDC_RADIO_ICON, IDC_RADIO_SMALLICON, IDC_RADIO_LIST and IDC_RADIO_REPORT respectively.
We need to handle BN_CLICKED message for the four radio buttons in order to respond to mouse events.
These message handlers are added through using Class Wizard. Within the member functions, the style of
the list control is changed according to which radio button is being clicked. The following is one of the
message handlers that sets the style of the list control to “Normal Icon”:
void CCCtlDlg::OnRadioIcon()
{
LONG lStyle;
}
lStyle=GetWindowLong(m_listCtrl.GetSafeHwnd(), GWL_STYLE);
lStyle&=~(LVS_TYPEMASK);
lStyle|=LVS_ICON;
SetWindowLong(m_listCtrl.GetSafeHwnd(), GWL_STYLE, lStyle);
First, the list control’s old style is retrieved by calling function ::GetWindowLong(…), and is bit-wisely
ANDed with LVS_TYPEMASK, which will turn off all the style bits. Then style LVS_ICON is added to the
window style (through bit-wise ORing), and function ::SetWindowLong(…) is called to update the new
style. Both function ::GetWindowLong(…) and ::SetWindowLong(…) require a window handle, it could be
obtained by calling function CWnd:: GetSafeHwnd().
The list control and tree control can also be implemented in SDI and MDI applications. In this case, we
need to use classes derived from CListView or CTreeView. Although the creating procedure is a little
different from that of a dialog box, the properties of the controls are exactly the same for two different
types of applications. We will further explore list control and tree control in chapter 15.
5.16 Tab Control
In the previous sample, we used radio buttons to let the user set the style of list control dynamically.
An alternate way of doing this is to use tab control, which is widely used in various types of applications.
Usually a tab control is used together with dialog box to implement property sheets, which can let the user
easily switch among different property pages. This topic will be discussed in a chapter 7. Here, we will
discuss some basics on how to implement tab control and handle its messages.
Using Tab Control
In MFC, tab control can be implemented by using class CTabCtrl. A tab control can be associated with
an image list, so we can display both image and text on each tab. The steps of using a tab control is very
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