求LPDRAWITEMSTRUCT的介绍

void COwnerDrawDlg::OnDrawItem(int nIDCtl, LPDRAWITEMSTRUCT lpDrawItemStruct)
{
char btnText[16];
    HBRUSH          hBrush ;
GetDlgItemText(lpDrawItemStruct->CtlID,btnText,16);
hBrush=CreateSolidBrush(RGB(213,192,228));
hBrush=(HBRUSH) SelectObject (lpDrawItemStruct->hDC,hBrush);
SetBkColor(lpDrawItemStruct->hDC,RGB(213,192,228));
SetTextColor(lpDrawItemStruct->hDC,RGB(0,0,255));
Rectangle(lpDrawItemStruct->hDC,lpDrawItemStruct->rcItem.left,lpDrawItemStruct->rcItem.top,lpDrawItemStruct->rcItem.right,lpDrawItemStruct->rcItem.bottom); DrawText(lpDrawItemStruct->hDC,btnText,-1,&lpDrawItemStruct->rcItem,
DT_SINGLELINE|DT_CENTER|DT_VCENTER);
DeleteObject(SelectObject(lpDrawItemStruct->hDC,hBrush));
if (lpDrawItemStruct->itemState & ODS_SELECTED)
InvertRect (lpDrawItemStruct->hDC, &lpDrawItemStruct->rcItem);
}
DRAWITEMSTRUCT
The DRAWITEMSTRUCT structure provides information the owner window must have to determine how to paint an owner-drawn control or menu item. The owner window of the owner-drawn control or menu item receives a pointer to this structure as the lParam parameter of the WM_DRAWITEM message. typedef struct tagDRAWITEMSTRUCT {
  UINT      CtlType;
  UINT      CtlID;
  UINT      itemID;
  UINT      itemAction;
  UINT      itemState;
  HWND      hwndItem;
  HDC       hDC;
  RECT      rcItem;
  ULONG_PTR itemData;
} DRAWITEMSTRUCT;
Members
CtlType
Specifies the control type. This member can be one of the values shown in the following table. Value Meaning
ODT_BUTTON Owner-drawn button
ODT_COMBOBOX Owner-drawn combo box
ODT_LISTBOX Owner-drawn list box
ODT_LISTVIEW List view control
ODT_MENU Owner-drawn menu item
ODT_STATIC Owner-drawn static control
ODT_TAB Tab control
CtlID
Specifies the identifier of the combo box, list box, button, or static control. This member is not used for a menu item.
itemID
Specifies the menu item identifier for a menu item or the index of the item in a list box or combo box. For an empty list box or combo box, this member can be –1. This allows the application to draw only the focus rectangle at the coordinates specified by the rcItem member even though there are no items in the control. This indicates to the user whether the list box or combo box has the focus. How the bits are set in the itemAction member determines whether the rectangle is to be drawn as though the list box or combo box has the focus.
itemAction
Specifies the drawing action required. This member can be one or more of the values shown in the following table. Value Meaning
ODA_DRAWENTIRE The entire control needs to be drawn.
ODA_FOCUS The control has lost or gained the keyboard focus. The itemState member should be checked to determine whether the control has the focus.
ODA_SELECT The selection status has changed. The itemState member should be checked to determine the new selection state.
itemState
Specifies the visual state of the item after the current drawing action takes place. This member can be a combination of the values shown in the following table. Value Meaning
ODS_CHECKED The menu item is to be checked. This bit is used only in a menu.
ODS_COMBOBOXEDIT The drawing takes place in the selection field (edit control) of an owner-drawn combo box.
ODS_DEFAULT The item is the default item.
ODS_DISABLED The item is to be drawn as disabled.
ODS_FOCUS The item has the keyboard focus.
ODS_GRAYED The item is to be grayed. This bit is used only in a menu.
ODS_HOTLIGHT Windows 98/Me, Windows 2000 or later: The item is being hot-tracked, that is, the item will be highlighted when the mouse is on the item.
ODS_INACTIVE Windows 98/Me, Windows 2000 or later: The item is inactive and the window associated with the menu is inactive.
ODS_NOACCEL Windows 2000 or later: The control is drawn without the keyboard accelerator cues.
ODS_NOFOCUSRECT Windows 2000 or later: The control is drawn without focus indicator cues.
ODS_SELECTED The menu item's status is selected.
hwndItem
Handle to the control for combo boxes, list boxes, buttons, and static controls. For menus, this member is a handle to the menu containing the item.
hDC
Handle to a device context; this device context must be used when performing drawing operations on the control.
rcItem
Specifies a rectangle that defines the boundaries of the control to be drawn. This rectangle is in the device context specified by the hDC member. The system automatically clips anything that the owner window draws in the device context for combo boxes, list boxes, and buttons, but does not clip menu items. When drawing menu items, the owner window must not draw outside the boundaries of the rectangle defined by the rcItem member.
itemData
Specifies the application-defined value associated with the menu item. For a control, this parameter specifies the value last assigned to the list box or combo box by the LB_SETITEMDATA or CB_SETITEMDATA message. If the list box or combo box has the LBS_HASSTRINGS or CBS_HASSTRINGS style, this value is initially zero. Otherwise, this value is initially the value that was passed to the list box or combo box in the lParam parameter of one of the following messages:
CB_ADDSTRING
CB_INSERTSTRING
LB_ADDSTRING
LB_INSERTSTRING
If ctlType is ODT_BUTTON or ODT_STATIC, itemData is zero. Requirements

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求LPDRAWITEMSTRUCT的介绍

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