Advanced MFC Programming

Chapter 5. Common Controls
similar to that of list control and tree control: first we need to add tab control resource to the dialog
template; then in the dialog’s initialization stage, we need to create the image list, select it into the tab
control, and initialize the tab control. The function that can be used to assign image list to a tab control is
CTabCtrl::SetImageList(…), which has the following format:
CImageList *CTabCtrl::SetImageList(CImageList *pImageList);
The function that can be used to add an item to the tab control is CTabCtrl::InsertItem(…):
BOOL CTabCtrl::InsertItem(int nItem, TC_ITEM *pTabCtrlItem);
The first parameter of this function is the index of the tab (zero based), and the second parameter is a
pointer to TC_ITEM type object. Before calling this function, we need to stuff structure TC_ITEM with tab’s
information:
typedef struct _TC_ITEM {
UINT mask;
UINT lpReserved1;
UINT lpReserved2;
LPSTR pszText;
int cchTextMax;
int iImage;
LPARAM lParam;
} TC_ITEM;
We need to use three members of this structure in order to create a tab with both text and image: mask,
pszText and iImage. Member mask indicates which of the other members of this structure contains valid
data; member pszText is a pointer to string text; and iImage is an image index to the associated image list.
We see that using this structure is very similar to that of TV_ITEM and LV_ITEM.
To respond to tab control’s activities, we need to add message handlers for it. The most commonly
used messages of tab control are TCN_SELCHANGE and TCN_SELCHANGING, which indicate that the current
selection has changed or the current selection is about to change respectively.
Sample 5.16\CCtl demonstrates how to use tab control, it is based on sample 5.15\CCtl. In this sample,
four radio buttons are replaced by a tab control IDC_TAB (see Figure 5-14). Also, message handlers of radio
buttons are removed. In order to access the tab control, a CTabCtrl type control variable m_tabCtrl is
added to class CCCtlDlg through using Class Wizard. Beside this, four bitmap resources IDB_BITMAP_ICON,
IDB_BITMAP_SMALLICON, IDB_BITMAP_LIST and IDB_BITMAP_REPORT are added to the application to create
image list for tab control.
In function CCCtlDlg::OnInitDialog(), first the image list is created and assigned to the tab control.
Next, four items are added to the tab control:
……
……
……
BOOL CCCtlDlg::OnInitDialog()
{
TC_ITEM tc_item;
CImageList *pilTab;
CBitmap bmp;
pilTab=new CImageList();
VERIFY(pilTab->Create(TAB_BMP_WIDTH, TAB_BMP_HEIGHT, ILC_COLOR, 4, 0));
bmp.LoadBitmap(IDB_BITMAP_ICON);
pilTab->Add(&bmp, RGB(127, 127, 127));
bmp.DeleteObject();
bmp.LoadBitmap(IDB_BITMAP_SMALLICON);
pilTab->Add(&bmp, RGB(127, 127, 127));
bmp.DeleteObject();
bmp.LoadBitmap(IDB_BITMAP_LIST);
pilTab->Add(&bmp, RGB(127, 127, 127));
bmp.DeleteObject();
bmp.LoadBitmap(IDB_BITMAP_REPORT);
pilTab->Add(&bmp, RGB(127, 127, 127));
bmp.DeleteObject();
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