I simply want to open a child dialog and have it print a result from the parent dialog in one of the child's static text controls. Using breakpoints I noticed that both DoDataExchange and my overloaded OnInitDialog are never called in the child so the static text control crashes any time i try to print something to it. The child dialog does display itself fine otherwise.
What could be the problem ?
//in parent.cpp
CResultsDlg childResultsDlg = this;
childResultsDlg.DoModal(15.7); //overloaded to pass value to a child member var
more information from my previous post
Child Dialog - SetWindowTextA or SendMessageA crashes program - MFC
All of the basics of MFC are covered in the SCRIBBLE tutorial.
http://msdn.microsoft.com/en-us/library/f35t8fts(v=vs.90).aspx
An example of passing data into a dialog and displaying that data in dialog controls is provided in the tutorial with the CPenWidthsDlg.
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I'm using MFC to build an application with two dialogs.
When I press a button in the parent dialog a new window including a Combobox should apprear.
I created a first dialog with a button "New". This button will open the second dialog.
Therefor I created a second dialog with a Combobox. The Combobox has a linked variable variableCombobox. The second class is called CSecond.
Before I do anything in the new dialog I want to add an item to the Combobox.
In the first dialog class I create the new window like this:
void CFirstDlg::OnBnClickedNew()
{
CSecond dlg2 = new CSecond();
dlg2.variableCombobox.AddString(L"test");
dlg2.DoModal();
}
The program crashes in the line I want to add the test string to the Combobox showing an assertion error.
I noticed that the dlg2 object is null but I don't know why.
Can anyone tell me how to create a second window immediately adding an new item in the Combobox of the second window?
The problem is the second dialog is a modal dialog. The windows does not exist before the call to DoModal() and no longer exist after that function returns. Therefore calling AddString on the combobox is not all right, since the combo box does not exist at that time.
The solution is to initialize the dialog with your desired values (like in the constructor for instance, or other methods) and then in OnInitDialog() use those values to setup the controls (including this call to AddString for the combobox).
I create dialog window in MFC using CWnd::DoModal function.
The window is instantiated in CWinApp::OnIdle()
CPatientFile pf;
pf.DoModal();
When the DoModal function returns the focus is not returned to the main window.
I tried to set focus manually
AfxGetMainWnd()->SetFocus();
Also tried to set the main window as foreground or active.
Generally I have touch screen, so when I close the Dialog I need to press the button on the main window to get it work.
So what is the right way to do it?
Just check the constructor of CPatientFile. It may be accepting the parent window CWnd *. Pass the main window as the parent.
Like
CPatientFile pf(this); //if this code is in main window class itelf
or
CPatientFile pf(AfxGetMainWnd());
Updated:
If you have instantiated the dialog from the main window, then the focus will automatically go back to the window when the dialog is closed. I am suspecting that you have instantiated the dialog from the app class itself (CWinApp) after creating the main window. If this is the case then the main window may not get the focus & you must create the dialog from within the main window. Or if you are creating the dialog in a separate thread.
As a work around you can use AfxGetMainWnd()->SetForegroundWindow() or AfxGetMainWnd()->SetActiveWindow(). But first I would try to find the cause of the issue & try to write better code (like suggested in above paragraph).
If you have copy-pasted, the statement is itself incorrect:
CPatientFile pf();
The next line shouldn't compile at all. Why? Because it is declaring a function named pf which returns CPatientFile.
If that is correct, may I ask if there is any multithreading involved. Is another thread creating a window?
How do you check if parent windows has (not) got the focus?
I want to build a MFC application, with one main dialog, and all the other dialogs are child of this main dialog (and embedded in it).
Now, i was able to embed the first child in the main dialog, but i want to pass to the next dialog (note that the order of opened dialogs is random), so i need to hide the first dialog and show another. To know which dialog is shown at the moment and hide it, i've tried using a CDialog variable to store the current opened dialog, but i get a CObject::operator =' : cannot access private member declared in class 'CObject' error.
Is there another way to do this "hide and show dialogs" game?
EDIT: Could i store some ID of the dialogs and use it to acomplish this task?
So i managed to accomplish this task using classes IDDs.
First, i store the last opened dialog's IDD
m_dlgStartPage.Create(CStartPageDlg::IDD, this);
m_openedWin.nDialogIDD = m_dlgStartPage.IDD;
m_dlgStartPage.ShowWindow(SW_SHOW);
Then, when a new dialog needs to be shown, i send a message to my main dialog (nIDD is the IDD of pending dialog to show):
AfxGetApp()->m_pMainWnd->SendMessage(WM_COMMAND_CHANGE_WINDOW, nIDD, 0);
And last, in my main dialog, i parse all the child dialogs and check if m_openedWin.nDialogIDD matches with each dialog's IDD, so i can hide it. After this, i parse once again all the chid dialogs and use the nIDD from the sent message to show the correct one.
I don't really like this approach, because of all the parsing and sent messages to the main dialog's class, so if anyone has a better idea or method, please post it.
When using MFC, if i have a main dialog box, then I another dialog box is called from the main, what message is sent to the main dialogue box to let it know it has focus, is it WM_SETFOCUS()? If so, what paramaters are needed? The problem I have is, a value is selected in the child dialog and I want it copied to an edit control in the main dialog box once it (the child dialog) closes. Right now, I have it so the second dialog box copies its value to a global variable, but once the second dialog box closes, I wanted to the main dialog box to grab the global variable and display in the edit control.
You can also use a member variable in the child dialog box, like
CChildDialogBox dlg;
if (dlg.DoModal() == IDOK) // child dialog saves the value in a CString member variable m_str
{ GetDlgItem(IDC_EDIT1)->SetWindowText(dlg.m_str);
}
This MSDN article describes how you can set up member variables connected to controls in a dialog box.
I realized my problem, really a beginner's mistake, I though after a DoModal call a function would immediately exit. I didn't know I could perform additional code(assigning the edit control variable a new value and then SetWindowText) after the call, before the function ended.
I have a first dialog with a simple button on it and while clicking the button, a second dialog is created using CDialog::Create(IDD,this). I would like the parent to be notified when the second dialog is destroyed but without adding any code to the second dialog i.e., without adding a m_pParent->Notify() line in OnDestroy method.
I have tried OnParentNotify, PreTranslateMessage, SubclassWindow in the parent dialog with no success. I have not used the WS_CHILD style for the second dialog. Any idea?
To complete: in fact, I have a ComboBox derived class (but the issue is the same with buttons) and I'm displaying a modeless Dialog instead of displaying the listbox. But I would like the control to be as generic as possible so that any modeless dialog could be used. That's why I do not want to add a specific notification in the second dialog. If I'm obliged, I will use this trick but I asked for a more generic solution. PreTranslateMessage only catches WM_PAINT, WM_NCMOUSELEAVE and WM_NCMOUSEMOVE.
Use a base class and have your parent refer to the modeless child by base class only. In the base PostNcDestroy have it post to the parent.
It doesn't make sense to have the parent do a bunch of filtering / spying on all messages. It does make sense to implement behavior in a base class that you want to have common to all the different future flavors you might have of the modeless child.
OnParentNotify() is not called since dialog2 is not a child of dialog1.
PreTranslateMessage() should help here (although I don't like this bullet). The trick is that a modeless dialog doesn't destroy itself when it's closed. If you want the dialog to die, it must call DestroyWindow() when it closes, such in an OnCancel() override.
Of course, the first thing that comes to mind is t wonder why you don't want to add custom notification in your modeless dialog code.
EDIT: Another method would consist in installing a message hook (for the current thread, Not the whole system!). This would help you catch all messages for all windows associated to the same thread as dialog1. See SetWindowsHookEx()
How about posting a main parent form event to the message queue?