MFC MDI Collecting control states for the "apply" button routine - c++

Question

It was mentioned in some of my other threads on my app on that my code was incorrect because the apply button is present. I understand that now. It was said to collect the controls and then when apply is hit to send the data.
I have now idea how to approach that. So for the sake of general education. I have 1 property sheet and 5 property pages. For the sake of just general controls in use. Between all the 5, there are only radio controls and buttons, no edit controls (yet).
Let's assume there are 2 radios buttons and 1 button on each page.. where page 1 is radio1, radio2, button 1 and page 2 is radio3, radio4, button2....and so on.
I know that when the user selects something like a button or radio that the IsModified(TRUE) needs to be called to enable the apply button from grayed to active.
What would the code look like to scan all the controls and then apply them? I've never done it and I can't seem to find an example that isn't already super busy to gain the understanding of how to do it.
Anyone have a tutorial or code snippet or build a primer from the controls that I described above that could demonstrate how to execute this?
Update:
Ok so I have the DDX variables added:
void CSettingsUserTabs::DoDataExchange(CDataExchange* pDX)
{
CMFCPropertyPage::DoDataExchange(pDX);
DDX_Control(pDX, STYLE_3D_USER, m_style_3d);
DDX_Control(pDX, STYLE_FLAT_USER, m_style_flat);
DDX_Control(pDX, STYLE_FLAT_SHARED_HORZ_SCROLL_USER, m_style_flat_shared_h_scroll);
DDX_Control(pDX, STYLE_3D_SCROLLED_USER, m_style_3d_scroll);
DDX_Control(pDX, STYLE_3D_ONENOTE_USER, m_style_onenote);
DDX_Control(pDX, STYLE_3D_VS2005_USER, m_style_vs2005);
DDX_Control(pDX, STYLE_3D_ROUNDED_USER, m_style_3d_rounded);
DDX_Control(pDX, STYLE_3D_ROUNDED_SCROLL_USER, m_style_3d_rounded_scroll);
}
My radio selection look like:
void CSettingsUserTabs::OnBnClicked3dUser()
{
//AfxGetMainWnd()->SendMessage(WM_COMMAND, STYLE_3D_USER);
UpdateData(TRUE);
}
void CSettingsUserTabs::OnBnClickedFlatUser()
{
// TODO: Add your control notification handler code here
//AfxGetMainWnd()->SendMessage(WM_COMMAND, STYLE_FLAT_USER);
UpdateData(TRUE);
}
..... and the rest of them....
So to me, when I click any radio button, I expect that it scans all of controls on that property page? If so, all the variables have the values..do I call IsModified(); to enable the apply button...which then executes all the radio values i.e. only one selected? Is that the flow?
Update 2:
So this is what my modal dialog code is in MainFrame.cpp:
void CMainFrame::OnSettingsTools()
{
SettingsSheet SettingsSheet(L"Application Settings");
CSettingsPowerUser pgePowerUser;
CSettingsToolbars pgeToolbars;
CSettingsTheme pgeTheme;
CSettingsUserTabs pgeUserTabs;
CSettingsReset pgeReset;
SettingsSheet.AddPage(&pgeToolbars);
SettingsSheet.AddPage(&pgeTheme);
SettingsSheet.AddPage(&pgeUserTabs);
SettingsSheet.AddPage(&pgePowerUser);
SettingsSheet.AddPage(&pgeReset);
INT_PTR nRet = -1;
nRet = SettingsSheet.DoModal();
// Handle the return value from DoModal
switch (nRet)
{
case -1:
AfxMessageBox(_T("Dialog box could not be created!"));
break;
case IDABORT:
// Do something
AfxMessageBox(_T("ABORT!"));
break;
case IDOK:
// Do something
OnUserTabStyles(1);
AfxMessageBox(_T("OK!"));
break;
case IDCANCEL:
// Do something
AfxMessageBox(_T("CANCEL"));
break;
default:
// Do something
break;
};
}
The routine to verify if any of the radios buttons are changed in SettingsTabs.cpp:
void CSettingsUserTabs::OnTabRadioClicked(UINT nCmdID)
{
BOOL IsChecked = nCmdID;
CheckRadioButton(STYLE_3D_USER, STYLE_3D_ROUNDED_SCROLL_USER, nCmdID);
UpdateData(TRUE);
m_tabCmdID = nCmdID;
SetModified();
}
What the member variables look like in SettingsUserTabs.cpp:
void CSettingsUserTabs::DoDataExchange(CDataExchange* pDX)
{
CMFCPropertyPage::DoDataExchange(pDX);
DDX_Radio(pDX, STYLE_3D_USER, m_style_3d);
DDX_Radio(pDX, STYLE_FLAT_USER, m_style_flat);
DDX_Radio(pDX, STYLE_FLAT_SHARED_HORZ_SCROLL_USER, m_style_flat_h_scroll);
DDX_Radio(pDX, STYLE_3D_SCROLLED_USER, m_style_3d_scroll);
DDX_Radio(pDX, STYLE_3D_ONENOTE_USER, m_style_3d_onenote);
DDX_Radio(pDX, STYLE_3D_VS2005_USER, m_style_vs2005);
DDX_Radio(pDX, STYLE_3D_ROUNDED_USER, m_style_3d_rounded);
DDX_Radio(pDX, STYLE_3D_ROUNDED_SCROLL_USER, m_style_3d_rounded_scroll);
}
What the constructor looks like in SettingsUserTabs.cpp:
CSettingsUserTabs::CSettingsUserTabs()
: CMFCPropertyPage(IDD_SETTINGS_TABS)
, m_style_3d(FALSE)
, m_style_flat(FALSE)
, m_style_flat_h_scroll(FALSE)
, m_style_3d_scroll(FALSE)
, m_style_3d_onenote(FALSE)
, m_style_vs2005(FALSE)
, m_style_3d_rounded(FALSE)
, m_style_3d_rounded_scroll(FALSE)
, m_tabCmdID(FALSE)
{
}
This issue I'm seeing now is when I try to use the member variable m_tabCmdID it is coming back to unknown identifier so I'm not sure why the member variable isn't be seen. I am was expecting to use it like OnUserTabStyles(m_tabCmdID); so that it would pass the argument of the selected button to the method OnUserTabStyles. For now I just dumped a 1 in there to see if the mechanism works. I just am not clear how to access the member variable from the SettingsUserTabs.cpp from the IDOK. What am I missing?
EDIT: The range of options are sequential in the resource.h as 200-207, that is something I'm aware of and I know many don't like range options as they can get corrupted...this is my code, so I have no worries about the range being messed with.
Update 3:
Ok, so I finally understand the mechanism that Constantine described with the help of:
https://helgeklein.com/blog/2009/10/radio-buttons-in-mfc-visual-studio-2008-c/
I didn't have the tab order right nor did I have the first control set to true for the group.
With that, I now get the values 0-7 mentioned in the button group when I debug as I click each radio button based on its position in the group from 0-7 i.e. 8 buttons. Here is what the code looks like now.
SettingsUserTabs.cpp:
CSettingsUserTabs::CSettingsUserTabs()
: CMFCPropertyPage(IDD_SETTINGS_TABS)
, m_style_tabs(FALSE)
{
}
void CSettingsUserTabs::DoDataExchange(CDataExchange* pDX)
{
CMFCPropertyPage::DoDataExchange(pDX);
DDX_Radio(pDX, STYLE_3D_USER, m_style_tabs);
}
void CSettingsUserTabs::OnTabRadioClicked(UINT nCmdID)
{
UpdateData(TRUE);
BOOL RadioValueSelected = m_style_tabs; // only here to see 0-7 value for debugging only, not needed, test only
SetModified();
}
The mainframe.cpp above (Update 2): void CMainFrame::OnSettingsTools() is still the same.
So now here is where my question still isn't clear, I call the domodal from mainframe.cpp, the member variable m_style_tabs is in SettingsUserTabs.cpp. When I try to access the member variable, it says unknown identifier when I try to do something like this after the domodal int temp = m_styles_tabs;. I have a this in the mainframe.cpp
void CMainFrame::DoDataExchange(CDataExchange* pDX)
{
// TODO: Add your specialized code here and/or call the base class
CMDIFrameWndEx::DoDataExchange(pDX);
}
I would expect that the member would be seen in mainframe.cpp so I can process it after the domodal which is what I thought the whole point of this is?
How do I access the member variable so I can do the OnApply to it? I think I almost got it, I am just unclear on how to execute the last few steps for the actual apply itself.
Update 4:
The reason I ask about the restart is when the user selects the tabs property page and choose 1 of 8 choices, that option is stored in the registry and read during the Oncreate and then uses that style. Since it is OnCreate I haven't found a way to "redraw" or use the new tab setting except to restart the app. So by doing the reg save > respawn > end old ...I would want the dialog to reopen at the same tab property page so the user can see what the changes are if the apply was selected...vs. some dialog that says "restart"..or whatever. Below is the code used to demonstrate how it is working now.
OutputWnd.cpp
int COutputWnd::OnCreate(LPCREATESTRUCT lpCreateStruct)
{
if (CDockablePane::OnCreate(lpCreateStruct) == -1)
return -1;
CRect rectDummy;
rectDummy.SetRectEmpty();
// Create User Define tab style:
int UserTabStyle = AfxGetApp()->GetProfileInt(_T("Settings"), _T("UserTabStyle"), 0); //Get value from registry
// If the key doesn't exist, UserTableStyle will be 0 or FALSE;
if (UserTabStyle != FALSE && UserTabStyle <= 8) { // User selected tab style type
int EnumUserTabStyle = UserTabStyle - 1; // Fix enum if key doesn't exist.
if (!m_wndTabs.Create(static_cast<CMFCTabCtrl::Style>(EnumUserTabStyle), rectDummy, this, 1))
{
TRACE0("Failed to create output tab window\n");
return -1; // fail to create
}
}
else { // Default tabs style if Reg key does not exist i.e. new install/program reset
if (!m_wndTabs.Create(CMFCTabCtrl::STYLE_FLAT, rectDummy, this, 1))
{
TRACE0("Failed to create output tab window\n");
return -1; // fail to create
}
}
… rest of function....
Update 5:
Here is the Apply in use from SettingsUserTabs.cpp:
BOOL CSettingsUserTabs::OnApply()
{
// TODO: Add your specialized code here and/or call the base class
AfxGetApp()->WriteProfileInt(_T("Settings"), _T("UserTabStyle"), m_style_tabs); // Save value to registry
return CMFCPropertyPage::OnApply();
}
Update 6:
Everything to this point is working, I ran into a road block trying to apply lessons learned here and at this link:
MFC MDI Substituting a class member dynamically
What was done in this topic was for the OutputWnd pane which works brilliantly! My MDI opens a file and uses CTabView and using the link shown in Update 6 allowed me to change the tabs on boot. Now that I have the OutputWnd doing it with OnApply, I'm trying to apply it to the document view when a file is loaded. I'm running into an access violation when I call the new function I created in TrainView.cpp and calling it from UserSettingsTabs.cpp. I thought it was the static_cast operation, but even if I do a simple bold using GetControlTabs() that also crashes (Shown in the commented out code, was on boot, now in OnApply to test theory). So clearly I need to capture the MDI document but not sure how that is done. I thought it would be as simple as:
GetTabControl().ModifyTabStyle(static_cast<CMFCTabCtrl::Style>(EnumUserTabStyle));
But when that crashed with a Cx000000005 access violation, I knew something was wrong on my end. I can't modify the CTabView operation, so I'm looking to see if we can fix what I'm doing wrong to have the OnApply change the tab styles without restarting as done in the OutputWnd we just fixed.
So as it stands, the OnApply that is working and now modded to try an integrate the CTabView functionality:
SettingsUserTabs.cpp:
BOOL CSettingsUserTabs::OnApply()
{
BOOL bResult = CMFCPropertyPage::OnApply();
if (bResult)
{
AfxGetApp()->WriteProfileInt(_T("Settings"), _T("UserTabStyle"), m_style_tabs); // Save value to registry
((CMainFrame*)AfxGetMainWnd())->m_wndOutput.m_wndTabs.ModifyTabStyle((CMFCTabCtrl::Style)m_style_tabs);
((CMainFrame*)AfxGetMainWnd())->m_wndOutput.m_wndTabs.RecalcLayout();
CTrainView* TrainTabs; // User Call from anywhere method
TrainTabs->TrainDocUpdateTabsControl();
}
return bResult;
}
I added the function CTrainView::TrainDocUpdateTabsControl() to update the tabs...the rest of the code is fully operation i.e. void CTrainView::OnInitialUpdate()
The TrainView.cpp:
IMPLEMENT_DYNCREATE(CTrainView, CTabView)
void CTrainView::OnInitialUpdate()
{
CMainFrame* pMainFrame = (CMainFrame*)AfxGetMainWnd();
pMainFrame->m_wndOutput.AddStringDebugTab(_T("Debug: TrainView--CTrainView::OnInitialUpdate()."));
// add views // cmb
AddView(RUNTIME_CLASS(CInformationView), AfxStringID(IDS_INFORMATION));
AddView(RUNTIME_CLASS(CChaptersView), AfxStringID(IDS_CHAPTERS));
// Nicely hack to access protected member
class CMFCTabCtrlEx : public CMFCTabCtrl
{
public:
void SetDisableScroll() { m_bScroll = FALSE; }
};
// One-Liner to Disable navigation control
((CMFCTabCtrlEx*)&GetTabControl())->SetDisableScroll();
GetTabControl().EnableTabSwap(TRUE);
GetTabControl().SetLocation(CMFCBaseTabCtrl::Location::LOCATION_BOTTOM);
//GetTabControl().SetActiveTabBoldFont(TRUE);
GetTabControl().EnableAutoColor(TRUE);
// Modify User Define tab style:
int UserTabStyle = AfxGetApp()->GetProfileInt(_T("Settings"), _T("UserTabStyle"), 0); //Get value from registry
// If the key doesn't exist, UserTableStyle will be 0 or FALSE;
if (UserTabStyle != FALSE && UserTabStyle <= 8) { // User selected tab style type
int EnumUserTabStyle = UserTabStyle - 1; // Fix enum if key doesn't exist.
GetTabControl().ModifyTabStyle(static_cast<CMFCTabCtrl::Style>(EnumUserTabStyle));
}
else { // Default tabs style if Reg key does not exist i.e. new install/program reset
GetTabControl().ModifyTabStyle(CMFCTabCtrl::STYLE_FLAT);
}
CTabView::OnInitialUpdate();
}
void CTrainView::TrainDocUpdateTabsControl()
{
CTabView::AssertValid();
GetTabControl().SetActiveTabBoldFont(TRUE); << CAUSES Cx000000005 ACCESS ERROR CRASH WHEN CALLED.
//int EnumUserTabStyle;
//int UserTabStyle = AfxGetApp()->GetProfileInt(_T("Settings"), _T("UserTabStyle"), 0); //Get value from registry
//((CMainFrame*)AfxGetMainWnd())->GetTabControl().ModifyTabStyle(static_cast<CMFCTabCtrl::Style>(EnumUserTabStyle));
}
Update 6 EDIT:
The tabview is created from Application.cpp like this:
//Load Train Template
m_pkDocTrainTemplate = new CMultiDocTemplate(
IDR_TRAIN, // Loads TRAIN operation
RUNTIME_CLASS(CTrainDoc),
RUNTIME_CLASS(CChildFrame),
RUNTIME_CLASS(CTrainView));
AddDocTemplate(m_pkDocTrainTemplate);
I tried to cast the m_pkDocTrainTemplate as I thought that was the pointer? Since it is MDI, I wasn't sure if there was an index issue since there can be multiple docs open simultaneously?

Answer 1

Below is an example of an application I wrote some time ago. It's a simple "Settings" dialog. Unlike yours, this one is derived from CDialogEx. But as CPropertyDialog is derived from CDialog, these apply in your case too.
Using the Wizard, I added member variables to the dialog class, bound to the dialog controls. Choose "Value", rather than "Control" in the "Category" combo in the Wizard. These are declared in the class definition. For simplicity, I only show three. There is a CString, an int and a BOOL variable, bound to an edit, a combo-box (drop-down list) and a check-box control respectively.
class CSettingsDlg : public CDialogEx
{
.
.
public:
CString m_DBConn;
int m_DumpSQL;
BOOL m_bLineNums;
}
In the implementation, the Wizard has modified the constructor and the DoDataExchange() member functions:
CSettingsDlg::CSettingsDlg(CWnd* pParent /*=NULL*/)
: CDialogEx(CSettingsDlg::IDD, pParent)
, m_DBConn(_T(""))
, m_DumpSQL(0)
, m_bLineNums(FALSE)
{
}
void CSettingsDlg::DoDataExchange(CDataExchange* pDX)
{
CDialogEx::DoDataExchange(pDX);
DDX_Text(pDX, IDC_EDIT_DBCONN, m_DBConn);
DDV_MaxChars(pDX, m_DBConn, 255);
DDX_CBIndex(pDX, IDC_COMBO_DUMPSQL, m_DumpSQL);
DDV_MinMaxInt(pDX, m_DumpSQL, 0, 2);
DDX_Check(pDX, IDC_CHECK_LINENUMS, m_bLineNums);
}
The values in the constructor are the initial (default) ones. The DoDataExchange() function calls the DDX/DDV routines. The DDX routines perform the transfer of data (controls<->variables), while the DDV ones the validation - they are optional. The DoDataExchange() function is called by UpdateData(). Also, the default implementation of OnOK() calls UpdateData(TRUE), and if successful closes the dialog.
You will need to enable the Apply button if something has been modified. You can capture notification messages like EN_CHANGE, EN_UPDATE, BN_CLICKED etc (add an event in the property editor) and call the SetModified() function - this can prove quite tedious, but I can't see any other way to do it.
Such a dialog class can be used in the application as shown below:
void CChildView::OnSetoptions()
{
// Create a Settings-dialog class instance
CSettingsDlg sd; // Main application window as parent - will block every UI item in the application
// Set initial values for the member variables
sd.m_DBConn = szDBconn;
sd.m_DumpSQL = nDumpSQL;
sd.m_bLineNums = bDumpLineNums;
if (sd.DoModal() == IDOK)
{
// Store the values entered by the user
lstrcpyn(szDBconn, sd.m_DBConn, MAX_PATH);
nDumpSQL = sd.m_DumpSQL;
bDumpLineNums = sd.m_bLineNums;
}
}
EDIT :
I have a usage example in the code section just above. The procedure is create an instance of the dialog class, set the member variables' values (initial values, eg read from the registry), call DoModal() and if successful store (copy) the variables somewhere else (if not discard them). This should be done in some event handler, like CMainFrame::OnSettingsTools() in Update2. The CMainFrame::DoDataExchange() override makes no sense.
It's quite strange that you can't access the m_style_tabs variable. Isn't it a non-static, public member of the CSettingsUserTabs class? It should be declared in SettingsUserTabs.h. Won't it work if you acceess it as pgeUserTabs.m_style_tabs? In the CSettingsUserTabs class functions it can accessed simply as m_style_tabs. Also I see it is initialized as FALSE in the constructor. Is it a BOOL and not an int? (btw BOOL is defined as int in Win32, so the compiler won't complain) But the Wizard generates an int variable for radio-buttons, optionally with range validation as well.
Another point, you don't normally need to call UpdateData(TRUE) in CSettingsUserTabs::OnTabRadioClicked(). Please leave only the SetModified() call there. UpdateData(TRUE) is typically called in the OnOK() function. And usually you don't need to override these, because the default implementation is sufficient. The CPropertyPage documentation btw mentions that The default implementation of OnApply calls OnOK.
EDIT 2 :
In OnApply() you should first check if validation was successful. Also, OnCreate() isn't a "method" that can be called directly. It should be considered an "event". It's called by the framework when a window is created. You should instead call Create(). In your case you can destroy the Output Window and create it anew (with the new style). But, I see that the CMFCTabCtrl class has a ModifyTabStyle() function, which you can try calling, (without destroying the windows and creating it again). So, your code would become:
BOOL CSettingsUserTabs::OnApply()
{
BOOL bResult = CMFCPropertyPage::OnApply();
if (bResult)
{
AfxGetApp()->WriteProfileInt(_T("Settings"), _T("UserTabStyle"), m_style_tabs); // Save value to registry
((CMainFraime*)AfxGetMainWnd())->m_wndOutput.m_wndTabs.ModifyTabStyle((CMFCTabCtrl::Style)m_style_tabs);
}
return bResult;
}
The above code won't compile, because the m_wndOutput and m_wndTabs members are protected. You will have to make them public.