CComboBox::SetDroppedWidth
Call this function to set the minimum allowable width, in pixels, of the list box of a combo box.
int SetDroppedWidth(
UINT nWidth
);
Parameters
- nWidth
The minimum allowable width of the list-box portion of the combo box, in pixels.
Return Value
If successful, the new width of the list box, otherwise CB_ERR.
Remarks
This function only applies to combo boxes with the CBS_DROPDOWN or CBS_DROPDOWNLIST style.
By default, the minimum allowable width of the drop-down list box is 0. When the list-box portion of the combo box is displayed, its width is the larger of the minimum allowable width or the combo box width.
Example
// Find the longest string in the combo box.
CString str;
CSize sz;
int dx = 0;
TEXTMETRIC tm;
CDC* pDC = m_pComboBox->GetDC();
CFont* pFont = m_pComboBox->GetFont();
// Select the listbox font, save the old font
CFont* pOldFont = pDC->SelectObject(pFont);
// Get the text metrics for avg char width
pDC->GetTextMetrics(&tm);
for (int i = 0; i < m_pComboBox->GetCount(); i++)
{
m_pComboBox->GetLBText(i, str);
sz = pDC->GetTextExtent(str);
// Add the avg width to prevent clipping
sz.cx += tm.tmAveCharWidth;
if (sz.cx > dx)
dx = sz.cx;
}
// Select the old font back into the DC
pDC->SelectObject(pOldFont);
m_pComboBox->ReleaseDC(pDC);
// Adjust the width for the vertical scroll bar and the left and right border.
dx += ::GetSystemMetrics(SM_CXVSCROLL) + 2*::GetSystemMetrics(SM_CXEDGE);
// Set the width of the list box so that every item is completely visible.
m_pComboBox->SetDroppedWidth(dx);
Requirements
Header: afxwin.h