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CButton::DrawItem

Called by the framework when a visual aspect of an owner-drawn button has changed.

virtual void DrawItem( 
   LPDRAWITEMSTRUCT lpDrawItemStruct  
);

Parameters

  • lpDrawItemStruct
    A long pointer to a DRAWITEMSTRUCT structure. The structure contains information about the item to be drawn and the type of drawing required.

Remarks

An owner-drawn button has the BS_OWNERDRAW style set. Override this member function to implement drawing for an owner-drawn CButton object. The application should restore all graphics device interface (GDI) objects selected for the display context supplied in lpDrawItemStruct before the member function terminates.

Also see the BS_ style values.

Example

// NOTE: CMyButton is a class derived from CButton. The CMyButton 
// object was created as follows: 
// 
// CMyButton myButton; 
// myButton.Create(_T("My button"), 
//      WS_CHILD|WS_VISIBLE|BS_PUSHBUTTON|BS_OWNERDRAW,  
//      CRect(10,10,100,30), pParentWnd, 1); 
// 

// This example implements the DrawItem method for a CButton-derived  
// class that draws the button's text using the color red. 
void CMyButton::DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct) 
{
   UINT uStyle = DFCS_BUTTONPUSH;

   // This code only works with buttons.
   ASSERT(lpDrawItemStruct->CtlType == ODT_BUTTON);

   // If drawing selected, add the pushed style to DrawFrameControl. 
   if (lpDrawItemStruct->itemState & ODS_SELECTED)
      uStyle |= DFCS_PUSHED;

   // Draw the button frame.
   ::DrawFrameControl(lpDrawItemStruct->hDC, &lpDrawItemStruct->rcItem, 
      DFC_BUTTON, uStyle);

   // Get the button's text.
   CString strText;
   GetWindowText(strText);

   // Draw the button text using the text color red.
   COLORREF crOldColor = ::SetTextColor(lpDrawItemStruct->hDC, RGB(255,0,0));
   ::DrawText(lpDrawItemStruct->hDC, strText, strText.GetLength(), 
      &lpDrawItemStruct->rcItem, DT_SINGLELINE|DT_VCENTER|DT_CENTER);
   ::SetTextColor(lpDrawItemStruct->hDC, crOldColor);
}

Requirements

Header: afxwin.h

See Also

Reference

CButton Class

Hierarchy Chart

CButton::SetButtonStyle

WM_DRAWITEM