Ownerdraw ComboBox Text Align Vertically Center - mfc

I am using owner-draw ComboBox in my MFC dialog based application.
I can draw Combobox's ListBox items but I cant set the ComboBox text in the ComboBox's edit control with vertical center alignment, it always renders on the top left of the edit control.
I need the text to be rendered on vertical center in the edit control.
How to achieve it?
CombobOx style :- CBS_DROPDOWN | CBS_OWNERDRAWFIXED | CBS_SORT | CBS_HASSTRINGS | CBS_UPPERCASE | WS_VSCROLL | WS_TABSTOP
BOOL CTestComboDlg::OnInitDialog()
{
CDialog::OnInitDialog();
// TODO: Add extra initialization here
COMBOBOXINFO cbi = { sizeof cbi};
m_ctrlCombo.GetComboBoxInfo(&cbi);
CRect r;
CWnd* p = CWnd::FromHandle(cbi.hwndItem);
((CEdit*)p)->GetRect(&r);
r.DeflateRect(10,10);
((CEdit*)p)->SetRect(r);
m_ctrlCombo.AddString("GHKL");
m_ctrlCombo.AddString("FGHJKL");
m_ctrlCombo.AddString("ASDFGH");
m_ctrlCombo.AddString("QWERTY");
m_ctrlCombo.SetCurSel(0);
return TRUE; // return TRUE unless you set the focus to a control
}
void CMyComboBox::DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct)
{
CDC dc;
dc.Attach(lpDrawItemStruct->hDC);
LPCTSTR lpszText = (LPCTSTR) lpDrawItemStruct->itemData;
ASSERT(lpszText != NULL);
if (lpDrawItemStruct->itemID != -1)
dc.DrawText(lpszText, strlen(lpszText),
&lpDrawItemStruct->rcItem,
DT_LEFT|DT_SINGLELINE|DT_VCENTER);
dc.Detach();
}
Thanks

The owner-drawn combo box control will be displayed taller than it is set in the dialog resource: default height of the combo box in the resource editor is 12 pixels, but in the running application it will be displayed 2 pixels taller.
So I used below code to adjust the height of the edit control of combobox and got the text vertically center aligned
TEXTMETRIC tm;
HDC hDC = ::GetDC(NULL);
CFont* pFont = GetFont();
HFONT hFontOld = (HFONT)SelectObject(hDC, pFont->GetSafeHandle());
GetTextMetrics(hDC, &tm);
SetItemHeight(-1,tm.tmHeight + tm.tmExternalLeading + 1);
SelectObject(hDC, hFontOld);
::ReleaseDC(NULL, hDC);

Related

How to find CStatic (text) bounding rect of actual content?

When I have a mfc CStatic control, I can read the control's window rect by
CStatic textStatic = GetDlgItem(IDC_TEXT_STATIC);
CRect rect;
textStatic.GetWindowRect(&rect);
ScreenToClient(rect);
However, this gives me the bounding rect of the control independent from the actual displayed text. If the text is longer than this, then the text is truncated, and if the text is shorter than this, it does not give me the 'right border' of the text.
For some dynamic resizing of dialogs, I would like to find the bounding rect (or at least the width) of the actually drawn text, not the control itself.
How do I get to this (programatically)?
You can call CDC::DrawTextEx with the DT_CALCRECT formatting option (see DrawTextEx). An appropriate device context is returned from a call to CWnd::GetDC:
CRect GetTextSize(int ctrlId) {
CWnd* pControl = GetDlgItem(ctrlId);
CString text;
pControl->GetWindowText(text);
CDC* pDC = pControl->GetDC();
CRect textRect;
pDC->DrawTextEx(text, &textRect, DT_CALCRECT, NULL);
return textRect;
}
IInspectable's answer above got me started, but was missing the bit to select the appropriate font (to deal with system font DPI setting). The following method now does what I need:
CRect GetControlTextRect(CWnd *pWnd)
{
CString text;
pWnd->GetWindowText(text);
CDC* pDC = pWnd->GetDC();
CFont* pFont = pWnd->GetParent()->GetFont();
pDC->SelectObject( pFont );
CRect textRect;
pWnd->GetWindowRect(&textRect);
pDC->DrawTextEx(text, &textRect, DT_CALCRECT, NULL);
return textRect;
}
Called f.e. like here:
CWnd * txtCtrl = GetDlgItem(IDC_STATIC); // IDC_STATIC is the resource ID of the control
CRect rect = GetControlTextRect( txtCtrl );
ScreenToClient(rect);
Or alternatively like:
CStatic txtCtrl = GetDlgItem(IDC_STATIC); // IDC_STATIC is the resource ID of the control
CRect rect = GetControlTextRect( &txtCtrl );
ScreenToClient(rect);

Wrong CListCtrl items drawing

I have my CListCtrlEx derived from CListCtrl. This list have style LVS_REPORT, LVS_OWNERDRAWFIXED and LVS_EX_GRIDLINES. I have added possibility to change font for this list. This works fine, but there is one bad thing - if I change font and before that I have not been scrolling list, then all list items redraws right, but if I have done scrolling before font changing, then list items redraws a little bit upper or lower than list grid horizontal lines, i. e. items text becomes overlapped by grid lines.
Here is how I changing list font:
LRESULT CListCtrlEx::OnSetFont(WPARAM wParam, LPARAM)
{
LRESULT res = Default();
CRect rc;
GetWindowRect(&rc);
WINDOWPOS wp;
wp.hwnd = m_hWnd;
wp.cx = rc.Width();
wp.cy = rc.Height();
wp.flags = SWP_NOACTIVATE | SWP_NOMOVE | SWP_NOOWNERZORDER | SWP_NOZORDER;
SendMessage(WM_WINDOWPOSCHANGED, 0, (LPARAM)&wp);
return res;
}
void CListCtrlEx::MeasureItem(LPMEASUREITEMSTRUCT lpMeasureItemStruct)
{
HDC hDC = ::GetDC(NULL);
CFont* pFont = GetFont();
HFONT hFontOld = (HFONT)SelectObject(hDC, pFont->GetSafeHandle());
CRect rect;
DrawText(hDC, _T(" "), 1, rect, DT_SINGLELINE | DT_CALCRECT);
lpMeasureItemStruct->itemHeight = rect.bottom - rect.top;
SelectObject(hDC, hFontOld);
::ReleaseDC(NULL, hDC);
}
UPD:
three people have clicked button UP and nobody knows what it can be? :(
UPD 1:
here's the class code
http://pastebin.com/UdXYEpF7 .h
http://pastebin.com/2HYe5AEd .cpp
I tried your code, it looks like ListView is exchanging messages with scroller, the header is also being resized, it's not really worth investigating. It's fine if you just set position to zero, you can save the old position and put it back.
void CListCtrlEx::SetupFont(int nSize, const CString& strName)
{
int saveIndex = GetTopIndex();
EnsureVisible(0, 0);
if (m_pFont.get()) m_pFont.get()->DeleteObject();
VERIFY(m_pFont.get()->CreatePointFont(nSize, strName));
SetFont(m_pFont.get());
//This scrolls to bottom, it ensures saveIndex will end up on top
//once the next EnsureVisible is called
if (GetItemCount())
EnsureVisible(GetItemCount() - 1, 1);
EnsureVisible(saveIndex, 1);
}

WinAPI. How to redraw window which has no background?

Hi I have WNDCLASSEX structure which has this data:
m_wndClass.cbSize = sizeof(WNDCLASSEX);
m_wndClass.style = CS_NOCLOSE;
m_wndClass.lpfnWndProc = WndProc;
m_wndClass.cbClsExtra = 0;
m_wndClass.cbWndExtra = 0;
m_wndClass.hInstance = GetModuleHandle(NULL);
m_wndClass.hIcon = NULL;
m_wndClass.hCursor = LoadCursor(NULL, IDC_ARROW);
m_wndClass.hbrBackground = NULL;
m_wndClass.lpszMenuName = NULL;
m_wndClass.lpszClassName = Checkbox::CHECKBOX_CLASS.c_str();
m_wndClass.hIconSm = NULL;
I need to have window without background, because I need to draw text on parent window and text may be any color.
Drawing works fine, code for drawing:
case WM_PAINT:
{
PAINTSTRUCT ps;
HDC dc = BeginPaint(window, &ps);
if (!classInfo->m_text.empty())
{
HDC wdc = GetDC(window);
SetBkMode(wdc,TRANSPARENT);
DrawText(wdc, classInfo->m_text.c_str(), -1, &classInfo->m_textRect, DT_CENTER | DT_VCENTER | DT_SINGLELINE | DT_NOCLIP);
ReleaseDC(window, wdc);
}
EndPaint(window, &ps);
break;
}
However I have method to change text of label:
void Checkbox::SetText(const String& text)
{
m_text = text;
SetTextRectSize(); //calculates size of RECT
if (m_window != NULL)
InvalidateRect(m_window, NULL, TRUE);
}
After I create window with label I see label, however if I want to change text on it, it doesn't change (I need to manualy resize window and it changes after that). However I hadn't have this problem at the time when I used to have colored background, for example my window class had this:
m_wndClass.hbrBackground = HBRUSH(COLOR_3DFACE+1);
I want to ask, how to update window which, has no background.
EDIT: I have tried some stuff
FillRect(dc, &rect, (HBRUSH)GetStockObject(NULL_BRUSH));
also tried to change window procedure:
case WM_CTLCOLORSTATIC:
{
HDC hdc = (HDC) wp;
SetBkMode (hdc, TRANSPARENT);
return (LRESULT)GetStockObject(NULL_BRUSH);
}
And the result is that I draw new text on previous, after setting text into some longer text part of label becomes corupted! see this but after resizing the main window my label becomes readable.
Your code doesn't set the device context's text foreground color for DrawText(), although the default is black. See SetTextColor().
SetBkMode(..., TRANSPARENT) just sets the background color/mode for the DrawText() rect, not the entire window.
You are asking about how to draw the window so it is transparent, but the problem isn't with the drawing at all.
The answer is essentially that everything you have done so far towards making a transparent window is wrong. It looks like the window is transparent, but in fact it is not, as you can see from the behaviour you describe when you move and resize the window. That's the classic symptom.
In other words, you haven't made the window transparent, you have just stopped drawing the background. What you see as the background is just whatever happened to be underneath the window when it was first drawn.
You need make a Layered window. To find out how to make transparent windows, go here:
http://msdn.microsoft.com/en-us/library/ms997507.aspx
Do you want Text/Check/Label be transparent on parent form?
You can Add WS_CLIPSIBLINGS and WS_EX_TRANSPARENT..
Use SetBkMode(hDC, TRANSPARENT) When WM_PAINT message

How to get the background colour of CTabCtrl?

I have a CTabCtrl on my dialog, and it has several labels (CStatic) on them. The problem is, the tab control has a white background, and the labels have grey backgrounds. I know why - the parent of the labels is actually the dialog, not the tab control. However, I should be able to use CWnd::OnCtlColor to provide a custom background brush for the labels:
HBRUSH MyDialog::OnCtlColor(CDC *pDC, CWnd *pWnd, UINT nCtlColor)
{
HBRUSH hBrush = __super::OnCtlColor(pDC, pWnd, nCtlColor);
const int dialogId = pWnd->GetDlgCtrlID();
if (dialogId == IDC_MY_CONTROL)
{
pDC->SetBkMode(TRANSPARENT);
hBrush = m_nullBrush;
}
return hBrush;
}
Here I use m_nullBrush to provide a brush to paint the background of the labels with, the only trouble is, I don't know how to get the tab's background colour, and instead have got it hardcoded with m_nullBrush.CreateStockObject(WHITE_BRUSH);.
Even if I re-parent the labels onto the tab control, they still end up with a grey background (even though the tab control has a white background).
How do I retrieve the background colour of a CTabCtrl?
You can put your controls in a child dialog and you must enable theme for this child dialog using EnableThemeDialogTexture.
#include "Uxtheme.h"
...
BOOL CTabDemoDlg::OnInitDialog()
{
CDialogEx::OnInitDialog();
COneDlg* OneDlg= new COneDlg;
OneDlg->Create(IDD_ONE, this);
AddPage(OneDlg, L"One");
return TRUE;
}
void CTabDemoDlg::AddPage(CDialog *Dialog, const wchar_t* Title)
{
if (IsAppThemed())
EnableThemeDialogTexture(*Dialog, ETDT_ENABLETAB);
CRect Rect;
TabCtl.GetWindowRect(Rect);
Rect.top+= 20;
Rect.InflateRect(-4, -4);
ScreenToClient(Rect);
Dialog->MoveWindow(Rect);
TabCtl.InsertItem(0, Title);
}
IDD_ONE DIALOGEX 0, 0, 224, 111
STYLE DS_SETFONT | DS_FIXEDSYS | DS_CONTROL | WS_CHILD | WS_VISIBLE
EXSTYLE WS_EX_CONTROLPARENT
FONT 8, "MS Shell Dlg", 400, 0, 0x1
BEGIN
CONTROL "Check1",IDC_CHECK1,"Button",BS_AUTOCHECKBOX | WS_TABSTOP,20,16,39,10
LTEXT "Static",IDC_STATIC,20,36,19,8
EDITTEXT IDC_EDIT1,20,48,40,14,ES_AUTOHSCROLL
PUSHBUTTON "Button1",IDC_BUTTON1,84,16,50,14
END

Transparent radio button control with themes using Win32

I am trying to make a radio button control with a transparent background using only Win32 when themes are enabled. The reason for doing this is to allow a radio button to be placed over an image and have the image show (rather than the grey default control background).
What happens out of the box is that the control will have the grey default control background and the standard method of changing this by handling either WM_CTLCOLORSTATIC or WM_CTLCOLORBTN as shown below does not work:
case WM_CTLCOLORSTATIC:
hdcStatic = (HDC)wParam;
SetTextColor(hdcStatic, RGB(0,0,0));
SetBkMode(hdcStatic,TRANSPARENT);
return (LRESULT)GetStockObject(NULL_BRUSH);
break;
My research so far indicates that Owner Draw is the only way to achieve this. I've managed to get most of the way with an Owner Draw radio button - with the code below I have a radio button and a transparent background (the background is set in WM_CTLCOLORBTN). However, the edges of the radio check are cut off using this method - I can get them back by uncommenting the call to the function DrawThemeParentBackgroundEx but this breaks the transparency.
void DrawRadioControl(HWND hwnd, HTHEME hTheme, HDC dc, bool checked, RECT rcItem)
{
if (hTheme)
{
static const int cb_size = 13;
RECT bgRect, textRect;
HFONT font = (HFONT)SendMessageW(hwnd, WM_GETFONT, 0, 0);
WCHAR *text = L"Experiment";
DWORD state = ((checked) ? RBS_CHECKEDNORMAL : RBS_UNCHECKEDNORMAL) | ((bMouseOverButton) ? RBS_HOT : 0);
GetClientRect(hwnd, &bgRect);
GetThemeBackgroundContentRect(hTheme, dc, BP_RADIOBUTTON, state, &bgRect, &textRect);
DWORD dtFlags = DT_VCENTER | DT_SINGLELINE;
if (dtFlags & DT_SINGLELINE) /* Center the checkbox / radio button to the text. */
bgRect.top = bgRect.top + (textRect.bottom - textRect.top - cb_size) / 2;
/* adjust for the check/radio marker */
bgRect.bottom = bgRect.top + cb_size;
bgRect.right = bgRect.left + cb_size;
textRect.left = bgRect.right + 6;
//Uncommenting this line will fix the button corners but breaks transparency
//DrawThemeParentBackgroundEx(hwnd, dc, DTPB_USECTLCOLORSTATIC, NULL);
DrawThemeBackground(hTheme, dc, BP_RADIOBUTTON, state, &bgRect, NULL);
if (text)
{
DrawThemeText(hTheme, dc, BP_RADIOBUTTON, state, text, lstrlenW(text), dtFlags, 0, &textRect);
}
}
else
{
// Code for rendering the radio when themes are not present
}
}
The method above is called from WM_DRAWITEM as shown below:
case WM_DRAWITEM:
{
LPDRAWITEMSTRUCT pDIS = (LPDRAWITEMSTRUCT)lParam;
hTheme = OpenThemeData(hDlg, L"BUTTON");
HDC dc = pDIS->hDC;
wchar_t sCaption[100];
GetWindowText(GetDlgItem(hDlg, pDIS->CtlID), sCaption, 100);
std::wstring staticText(sCaption);
DrawRadioControl(pDIS->hwndItem, hTheme, dc, radio_group.IsButtonChecked(pDIS->CtlID), pDIS->rcItem, staticText);
SetBkMode(dc, TRANSPARENT);
SetTextColor(hdcStatic, RGB(0,0,0));
return TRUE;
}
So my question is two parts I suppose:
Have I missed some other way to achieve my desired result?
Is it possible to fix the clipped button corners issue with my code and still have a transparent background
After looking at this on and off for nearly three months I've finally found a solution that I'm pleased with. What I eventually found was that the radio button edges were for some reason not being drawn by the routine within WM_DRAWITEM but that if I invalidated the radio button control's parent in a rectangle around the control, they appeared.
Since I could not find a single good example of this I'm providing the full code (in my own solution I have encapsulated my owner drawn controls into their own class, so you will need to provide some details such as whether the button is checked or not)
This is the creation of the radiobutton (adding it to the parent window) also setting GWL_UserData and subclassing the radiobutton:
HWND hWndControl = CreateWindow( _T("BUTTON"), caption, WS_CHILD | WS_VISIBLE | BS_OWNERDRAW,
xPos, yPos, width, height, parentHwnd, (HMENU) id, NULL, NULL);
// Using SetWindowLong and GWL_USERDATA I pass in the this reference, allowing my
// window proc toknow about the control state such as if it is selected
SetWindowLong( hWndControl, GWL_USERDATA, (LONG)this);
// And subclass the control - the WndProc is shown later
SetWindowSubclass(hWndControl, OwnerDrawControl::WndProc, 0, 0);
Since it is owner draw we need to handle the WM_DRAWITEM message in the parent window proc.
case WM_DRAWITEM:
{
LPDRAWITEMSTRUCT pDIS = (LPDRAWITEMSTRUCT)lParam;
hTheme = OpenThemeData(hDlg, L"BUTTON");
HDC dc = pDIS->hDC;
wchar_t sCaption[100];
GetWindowText(GetDlgItem(hDlg, pDIS->CtlID), sCaption, 100);
std::wstring staticText(sCaption);
// Controller here passes to a class that holds a map of all controls
// which then passes on to the correct instance of my owner draw class
// which has the drawing code I show below
controller->DrawControl(pDIS->hwndItem, hTheme, dc, pDIS->rcItem,
staticText, pDIS->CtlID, pDIS->itemState, pDIS->itemAction);
SetBkMode(dc, TRANSPARENT);
SetTextColor(hdcStatic, RGB(0,0,0));
CloseThemeData(hTheme);
return TRUE;
}
Here is the DrawControl method - it has access to class level variables to allow state to be managed since with owner draw this is not handled automatically.
void OwnerDrawControl::DrawControl(HWND hwnd, HTHEME hTheme, HDC dc, bool checked, RECT rcItem, std::wstring caption, int ctrlId, UINT item_state, UINT item_action)
{
// Check if we need to draw themed data
if (hTheme)
{
HWND parent = GetParent(hwnd);
static const int cb_size = 13;
RECT bgRect, textRect;
HFONT font = (HFONT)SendMessageW(hwnd, WM_GETFONT, 0, 0);
DWORD state;
// This method handles both radio buttons and checkboxes - the enums here
// are part of my own code, not Windows enums.
// We also have hot tracking - this is shown in the window subclass later
if (Type() == RADIO_BUTTON)
state = ((checked) ? RBS_CHECKEDNORMAL : RBS_UNCHECKEDNORMAL) | ((is_hot_) ? RBS_HOT : 0);
else if (Type() == CHECK_BOX)
state = ((checked) ? CBS_CHECKEDNORMAL : CBS_UNCHECKEDNORMAL) | ((is_hot_) ? RBS_HOT : 0);
GetClientRect(hwnd, &bgRect);
// the theme type is either BP_RADIOBUTTON or BP_CHECKBOX where these are Windows enums
DWORD theme_type = ThemeType();
GetThemeBackgroundContentRect(hTheme, dc, theme_type, state, &bgRect, &textRect);
DWORD dtFlags = DT_VCENTER | DT_SINGLELINE;
if (dtFlags & DT_SINGLELINE) /* Center the checkbox / radio button to the text. */
bgRect.top = bgRect.top + (textRect.bottom - textRect.top - cb_size) / 2;
/* adjust for the check/radio marker */
// The +3 and +6 are a slight fudge to allow the focus rectangle to show correctly
bgRect.bottom = bgRect.top + cb_size;
bgRect.left += 3;
bgRect.right = bgRect.left + cb_size;
textRect.left = bgRect.right + 6;
DrawThemeBackground(hTheme, dc, theme_type, state, &bgRect, NULL);
DrawThemeText(hTheme, dc, theme_type, state, caption.c_str(), lstrlenW(caption.c_str()), dtFlags, 0, &textRect);
// Draw Focus Rectangle - I still don't really like this, it draw on the parent
// mainly to work around the way DrawFocus toggles the focus rect on and off.
// That coupled with some of my other drawing meant this was the only way I found
// to get a reliable focus effect.
BOOL bODAEntire = (item_action & ODA_DRAWENTIRE);
BOOL bIsFocused = (item_state & ODS_FOCUS);
BOOL bDrawFocusRect = !(item_state & ODS_NOFOCUSRECT);
if (bIsFocused && bDrawFocusRect)
{
if ((!bODAEntire))
{
HDC pdc = GetDC(parent);
RECT prc = GetMappedRectanglePos(hwnd, parent);
DrawFocus(pdc, prc);
}
}
}
// This handles drawing when we don't have themes
else
{
TEXTMETRIC tm;
GetTextMetrics(dc, &tm);
RECT rect = { rcItem.left ,
rcItem.top ,
rcItem.left + tm.tmHeight - 1,
rcItem.top + tm.tmHeight - 1};
DWORD state = ((checked) ? DFCS_CHECKED : 0 );
if (Type() == RADIO_BUTTON)
DrawFrameControl(dc, &rect, DFC_BUTTON, DFCS_BUTTONRADIO | state);
else if (Type() == CHECK_BOX)
DrawFrameControl(dc, &rect, DFC_BUTTON, DFCS_BUTTONCHECK | state);
RECT textRect = rcItem;
textRect.left = rcItem.left + 19;
SetTextColor(dc, ::GetSysColor(COLOR_BTNTEXT));
SetBkColor(dc, ::GetSysColor(COLOR_BTNFACE));
DrawText(dc, caption.c_str(), -1, &textRect, DT_WORDBREAK | DT_TOP);
}
}
Next is the window proc that is used to subclass the radio button control - this
is called with all windows messages and handles several before then passing unhandled
ones on to the default proc.
LRESULT OwnerDrawControl::WndProc(HWND hWnd, UINT uMsg, WPARAM wParam,
LPARAM lParam, UINT_PTR uIdSubclass, DWORD_PTR dwRefData)
{
// Get the button parent window
HWND parent = GetParent(hWnd);
// The page controller and the OwnerDrawControl hold some information we need to draw
// correctly, such as if the control is already set hot.
st_mini::IPageController * controller = GetWinLong<st_mini::IPageController *> (parent);
// Get the control
OwnerDrawControl *ctrl = (OwnerDrawControl*)GetWindowLong(hWnd, GWL_USERDATA);
switch (uMsg)
{
case WM_LBUTTONDOWN:
if (controller)
{
int ctrlId = GetDlgCtrlID(hWnd);
// OnCommand is where the logic for things like selecting a radiobutton
// and deselecting the rest of the group lives.
// We also call our Invalidate method there, which redraws the radio when
// it is selected. The Invalidate method will be shown last.
controller->OnCommand(parent, ctrlId, 0);
return (0);
}
break;
case WM_LBUTTONDBLCLK:
// We just treat doubleclicks as clicks
PostMessage(hWnd, WM_LBUTTONDOWN, wParam, lParam);
break;
case WM_MOUSEMOVE:
{
if (controller)
{
// This is our hot tracking allowing us to paint the control
// correctly when the mouse is over it - it sets flags that get
// used by the above DrawControl method
if(!ctrl->IsHot())
{
ctrl->SetHot(true);
// We invalidate to repaint
ctrl->InvalidateControl();
// Track the mouse event - without this the mouse leave message is not sent
TRACKMOUSEEVENT tme;
tme.cbSize = sizeof(TRACKMOUSEEVENT);
tme.dwFlags = TME_LEAVE;
tme.hwndTrack = hWnd;
TrackMouseEvent(&tme);
}
}
return (0);
}
break;
case WM_MOUSELEAVE:
{
if (controller)
{
// Turn off the hot display on the radio
if(ctrl->IsHot())
{
ctrl->SetHot(false);
ctrl->InvalidateControl();
}
}
return (0);
}
case WM_SETFOCUS:
{
ctrl->InvalidateControl();
}
case WM_KILLFOCUS:
{
RECT rcItem;
GetClientRect(hWnd, &rcItem);
HDC dc = GetDC(parent);
RECT prc = GetMappedRectanglePos(hWnd, parent);
DrawFocus(dc, prc);
return (0);
}
case WM_ERASEBKGND:
return 1;
}
// Any messages we don't process must be passed onto the original window function
return DefSubclassProc(hWnd, uMsg, wParam, lParam);
}
Finally the last little piece of the puzzle is that you need to invalidate the control (redraw it) at the right times. I eventually found that invalidating the parent allowed the drawing to work 100% correctly. This was causing flicker until I realised that I could get away by only invalidating a rectangle as big as the radio check, rather than as big as the whole control including text as I had been.
void InvalidateControl()
{
// GetMappedRectanglePos is my own helper that uses MapWindowPoints
// to take a child control and map it to its parent
RECT rc = GetMappedRectanglePos(ctrl_, parent_);
// This was my first go, that caused flicker
// InvalidateRect(parent_, &rc_, FALSE);
// Now I invalidate a smaller rectangle
rc.right = rc.left + 13;
InvalidateRect(parent_, &rc, FALSE);
}
A lot of code and effort for something that should be simple - drawing a themed radio button over a background image. Hopefully the answer will save someone else some pain!
* One big caveat with this is it only works 100% correctly for owner controls that are over a background (such as a fill rectangle or an image). That is ok though, since it is only needed when drawing the radio control over a background.
I've done this some time ago as well. I remember the key was to just create the (radio) buttons as usual. The parent must be the dialog or window, not a tab control. You could do it differently but I created a memory dc (m_mdc) for the dialog and painted the background on that. Then add the OnCtlColorStatic and OnCtlColorBtn for your dialog:
virtual HBRUSH OnCtlColorStatic(HDC hDC, HWND hWnd)
{
RECT rc;
GetRelativeClientRect(hWnd, m_hWnd, &rc);
BitBlt(hDC, 0, 0, rc.right - rc.left, rc.bottom - rc.top, m_mdc, rc.left, rc.top, SRCCOPY);
SetBkColor(hDC, GetSysColor(COLOR_BTNFACE));
if (IsAppThemed())
SetBkMode(hDC, TRANSPARENT);
return (HBRUSH)GetStockObject(NULL_BRUSH);
}
virtual HBRUSH OnCtlColorBtn(HDC hDC, HWND hWnd)
{
return OnCtlColorStatic(hDC, hWnd);
}
The code uses some in-house classes and functions similar to MFC, but I think you should get the idea. As you can see it draws the background of these controls from the memory dc, that's key.
Give this a try and see if it works!
EDIT: If you add a tab control to the dialog and put the controls on the tab (that was the case in my app) you must capture it's background and copy it to the memory dc of the dialog. It's a bit of an ugly hack but it works, even if the machine is running some extravagant theme that uses a gradient tab background:
// calculate tab dispay area
RECT rc;
GetClientRect(m_tabControl, &rc);
m_tabControl.AdjustRect(false, &rc);
RECT rc2;
GetRelativeClientRect(m_tabControl, m_hWnd, &rc2);
rc.left += rc2.left;
rc.right += rc2.left;
rc.top += rc2.top;
rc.bottom += rc2.top;
// copy that area to background
HRGN hRgn = CreateRectRgnIndirect(&rc);
GetRelativeClientRect(m_hWnd, m_tabControl, &rc);
SetWindowOrgEx(m_mdc, rc.left, rc.top, NULL);
SelectClipRgn(m_mdc, hRgn);
SendMessage(m_tabControl, WM_PRINTCLIENT, (WPARAM)(HDC)m_mdc, PRF_CLIENT);
SelectClipRgn(m_mdc, NULL);
SetWindowOrgEx(m_mdc, 0, 0, NULL);
DeleteObject(hRgn);
Another interesting point, while we're busy now, to get it all non-flickering create the parent and children (buttons, statics, tabs etc) with the WS_CLIPCHILDREN and WS_CLIPSIBLINGS style. The the order of creation is essential: First create the controls you put on the tabs, then create the tab control. Not the other way around (although it feels more intuitive). That because the tab control should clip the area obscured by the controls on it :)
I can't immediately try this out, but so far as I recall, you don't need owner draw. You need to do this:
Return 1 from WM_ERASEBKGND.
Call DrawThemeParentBackground from WM_CTLCOLORSTATIC to draw the background there.
Return GetStockObject(NULL_BRUSH) from WM_CTLCOLORSTATIC.
Knowing the sizes and coordinates radio button, we will copy the
image to them closed.
Then we create a brush by means of
BS_PATTERN style CreateBrushIndirect
Farther according to the
usual scheme - we return handle to this brush in reply to COLOR -
the message (WM_CTLCOLORSTATIC).
I have no idea why you are doing it so difficult, this is best solved via CustomDrawing
This is my MFC Handler to draw a Notebook on a CTabCtrl control. I'm not really sure why i need to Inflate the Rectangle, because if i don't do it a black border is drawn.
And another conceptional bug MS made is IMHO that i have to overwrite the PreErase drawing phase instead of the PostErase. But if i do the later the checkbox is gone.
afx_msg void AguiRadioButton::OnCustomDraw(NMHDR* notify, LRESULT* res) {
NMCUSTOMDRAW* cd = (NMCUSTOMDRAW*)notify;
if (cd->dwDrawStage == CDDS_PREERASE) {
HTHEME theme = OpenThemeData(m_hWnd, L"Button");
CRect r = cd->rc; r.InflateRect(1,1,1,1);
DrawThemeBackground(theme, cd->hdc, TABP_BODY, 0, &r,NULL);
CloseThemeData(theme);
*res = 0;
}
*res = 0;
}