自绘CListBox，使用EnableWindow函数，字有点重影

[女神打Boss]

大致代码如下

class CColorListBox : public CListBox
{
	DECLARE_DYNAMIC(CColorListBox)



public:
	CColorListBox();
	virtual ~CColorListBox();

public:
	int AddString(LPCTSTR lpszItem);
	int AddString(LPCTSTR lpszItem, COLORREF rgb);

public:
	virtual void DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct);
	virtual void MeasureItem(LPMEASUREITEMSTRUCT lpMeasureItemStruct);
//cpp
void CColorListBox::DrawItem(LPDRAWITEMSTRUCT lpDIS) 
{
	if ((int)lpDIS->itemID < 0)
		return;

	CDC* pDC = CDC::FromHandle(lpDIS->hDC);

	COLORREF crText;
	CString sText;
	COLORREF crNorm = (COLORREF)lpDIS->itemData;		// Color information is in item data.
	COLORREF crHilite = RGB(255 - GetRValue(crNorm), 255 - GetGValue(crNorm), 255 - GetBValue(crNorm));

	// If item has been selected, draw the highlight rectangle using the item's color.
	if ((lpDIS->itemState & ODS_SELECTED) &&
		(lpDIS->itemAction & (ODA_SELECT | ODA_DRAWENTIRE)))
	{
		CBrush brush(RGB(51, 153, 255));
		pDC->FillRect(&lpDIS->rcItem, &brush);
	}

	// If item has been deselected, draw the rectangle using the window color.
	if (!(lpDIS->itemState & ODS_SELECTED) && (lpDIS->itemAction & ODA_SELECT))
	{
		CBrush brush(::GetSysColor(COLOR_WINDOW));
		pDC->FillRect(&lpDIS->rcItem, &brush);
	}

	// If item has focus, draw the focus rect.
	if ((lpDIS->itemAction & ODA_FOCUS) && (lpDIS->itemState & ODS_FOCUS))
		pDC->DrawFocusRect(&lpDIS->rcItem);

	// If item does not have focus, redraw (erase) the focus rect.
	if ((lpDIS->itemAction & ODA_FOCUS) && !(lpDIS->itemState & ODS_FOCUS))
		pDC->DrawFocusRect(&lpDIS->rcItem);


	// Set the background mode to TRANSPARENT to draw the text.
	int nBkMode = pDC->SetBkMode(TRANSPARENT);

	// If the item's color information is set, use the highlight color
	// gray text color, or normal color for the text.
	if (lpDIS->itemData)
	{
		if (lpDIS->itemState & ODS_SELECTED)
			crText = pDC->SetTextColor(crHilite);
		else if (lpDIS->itemState & ODS_DISABLED)
			crText = pDC->SetTextColor(::GetSysColor(COLOR_GRAYTEXT));
		else
			crText = pDC->SetTextColor(crNorm);
	}
	// Else the item's color information is not set, so use the
	// system colors for the text.
	else
	{
		if (lpDIS->itemState & ODS_SELECTED)
			crText = pDC->SetTextColor(::GetSysColor(COLOR_HIGHLIGHTTEXT));
		else if (lpDIS->itemState & ODS_DISABLED)
			crText = pDC->SetTextColor(::GetSysColor(COLOR_GRAYTEXT));
		else
			crText = pDC->SetTextColor(::GetSysColor(COLOR_WINDOWTEXT));
	}


	// Get and display item text.
	GetText(lpDIS->itemID, sText);
	CRect rect = lpDIS->rcItem;

	// Setup the text format.
	UINT nFormat = DT_LEFT | DT_SINGLELINE | DT_VCENTER;
	if (GetStyle() & LBS_USETABSTOPS)
		nFormat |= DT_EXPANDTABS;

	// Calculate the rectangle size before drawing the text.
	pDC->DrawText(sText, -1, &rect, nFormat | DT_CALCRECT);
	pDC->DrawText(sText, -1, &rect, nFormat);

	pDC->SetTextColor(crText);
	pDC->SetBkMode(nBkMode);
}

//-------------------------------------------------------------------
void CColorListBox::MeasureItem(LPMEASUREITEMSTRUCT lpMIS)
{
	lpMIS->itemHeight = ::GetSystemMetrics(SM_CYMENUCHECK);
}

//-------------------------------------------------------------------
int CColorListBox::AddString(LPCTSTR lpszItem)
{
	return ((CListBox*)this)->AddString(lpszItem);
}

//-------------------------------------------------------------------
int CColorListBox::AddString(LPCTSTR lpszItem, COLORREF rgb)
{
	int nItem = AddString(lpszItem);
	if (nItem >= 0)
		SetItemData(nItem, rgb);
	return nItem;
}
//调用
void CCListBoxTestDlg::OnBnClickedButton1()
{
	m_colorListBox.AddString("111000", RGB(0, 0, 0));
	m_colorListBox.AddString("111000", RGB(128, 128, 128));
}


void CCListBoxTestDlg::OnBnClickedCheck1()
{
	// TODO: 在此添加控件通知处理程序代码
	my_bCheck = !my_bCheck;
	m_colorListBox.EnableWindow(my_bCheck);
}

效果如图

当调用EnableWindow函数时字会出现重影现象，前面3项是我选择后恢复正常的字

求解决方法

[Eleven]

应该是设置了TRANSPARENT模式的缘故。
你刷新的时候如果先将文字的背景刷一下，然后再绘制文字应该效果就可以了~

[schlafenhamster]

check1 是什么 ？

[女神打Boss]

引用 1 楼 Eleven 的回复:

应该是设置了TRANSPARENT模式的缘故。
你刷新的时候如果先将文字的背景刷一下，然后再绘制文字应该效果就可以了~

我 TRANSPARENT属性是false啊

[Eleven]

我说的是你代码中写的
// Set the background mode to TRANSPARENT to draw the text.
int nBkMode = pDC->SetBkMode(TRANSPARENT);

[女神打Boss]

引用 2 楼 schlafenhamster 的回复:

check1 是什么 ？

是一个check box控件，my_bCheck是控件value变量，我点击它调用
void CCListBoxTestDlg::OnBnClickedCheck1()
{
// TODO: 在此添加控件通知处理程序代码
my_bCheck = !my_bCheck;
m_colorListBox.EnableWindow(my_bCheck);
}
就是设置m_colorListBox控件EnableWindow启用或禁用的

[schlafenhamster]

那个 包含 ListBox 的 方框 是 什么 CStatic ?

[女神打Boss]

引用 4 楼 Eleven 的回复:

我说的是你代码中写的
// Set the background mode to TRANSPARENT to draw the text.
int nBkMode = pDC->SetBkMode(TRANSPARENT);

thanks

[女神打Boss]

引用 6 楼 schlafenhamster 的回复:

那个 包含 ListBox 的 方框 是 什么 CStatic ?

是group box和check box 组合就这样子了，要设置ctrl + d的顺序就行了

[女神打Boss]

先画背景后写字就OK了
改成这样

	// Calculate the rectangle size before drawing the text.
	pDC->SetBkMode(nBkMode);
	pDC->DrawText(sText, -1, &rect, nFormat | DT_CALCRECT);
	pDC->DrawText(sText, -1, &rect, nFormat);
	pDC->SetTextColor(crText);