Create a windows panel that is invisible that still accepts click message - windows

I'm using c++/cli with visual studio 2010 express edition.
What I want to do is create a panel that is invisible but that still accepts/receives the click and double click messages and possibly other mouse input. If I set the controls visibility to FALSE then this seems to disable any mouse input.
I have tried getting the paint message and doing nothing (as was suggested by other sources) to try and make the panel simply not draw but not be invisible however the panel still seems to be drawing.
What should I be doing in the paint message to tell windows that I have draw the panel?
My panel drawing function is:
private: System::Void panel1_Paint(System::Object^ sender, System::Windows::Forms::PaintEventArgs^ e) {
}
If there are any other suggestions about how I could achieve this then that would be helpful.

In the end I scrapped this idea all together, the problem was to get a way of getting the mouse input from a window that had been "parentented" by a NativeWindow class. This meant that the window I was expecting to receive messages (the child window) was not receiving the messages.
In order to get the messages you need to override the event handler in your parent NativeWindow class. Here you can handle the event This is where I got the solution:
http://msdn.microsoft.com/en-us/library/system.windows.forms.nativewindow.createhandle.aspx

Related

MFC: how to show a welcome dialog first?

When launch the program, I want to show a welcome dialog first before showing the main window. My current approach is like below.
BOOL CMyApp::InitInstance()
{
...
// The one and only window has been initialized, so show and update it
m_pMainWnd->ShowWindow(SW_HIDE);
//m_pMainWnd->UpdateWindow();
// call DragAcceptFiles only if there's a suffix
// In an SDI app, this should occur after ProcessShellCommand
CWelcomeDialog welcome_dialog;
welcome_dialog.DoModal();
m_pMainWnd->ShowWindow(SW_SHOW);
m_pMainWnd->UpdateWindow();
return TRUE;
}
Towards the end of InitInstance(), originally it uses (SW_SHOW). At first, I try commenting it out but it still shows. So I change to (SW_HIDE). It works but has unpleasant visual artifacts. Is there way to stop showing the main window as early as possible?
Another issue is that when I hide main window and show the dialog, the dialog is not in the center position of the main window.
In general, how to implement a welcome dialog and to show it well-centered before anything else?

MFC: How do you Paint a CTabView Background When no tabs exist?

I what to display some text, probably using DrawText() on to the CTabView client area when no tabs exist to explain why they don't exist. However, CTabView::OnPaint() is not called except once at the app startup. Also when all tabs hidden the CTabView::OnDraw() is not called. I suppose the CMFCTabCtrl may be the one getting the OnPaint() callbacks? But nonetheless, how do you output something to that row/col of a CSplitterWnd occupied by a CTabView when all tabs are not shown (hidden via CMFCTabCtrl::ShowTab()). ??
TIA!!
The tab control works that way that all tab views are hidden - except the one which is open.
Where no tab view is open, none will receive a paint message (nor WM_ERASEBACKGROUND).
You could try implementing your paint stuff in the tab control's OnPaint handler.

How to show a dialog from another dialog?

I am newbie to MFC. I have a native C++ MFC app. I want to show a dialog from main dialog. In the main dialog I am having three button (Back, Next, Cancel) respectively.
On the Next button click event I am calling DoModal to show another dialog by hiding the main dialog as follows,
void CFirstPage::OnBnNextButton()
{
::ShowWindow(this->GetSafeHwnd(),SW_HIDE);
CSecondPage secondDlg;
secondDlg.DoModal();
}
void CSecondPage::OnBnBackBtnClicked()
{
::ShowWindow(this->GetSafeHwnd(),SW_HIDE);
CFirstPage FirstPage;
FirstPage.DoModal();
}
After executing this code snippet, the main dialog got hidden and even the application icon also disappears from the taskbar and again appears when the other dialog pops up.
(Basically I am having the same icon for both the dialogs, the icon should not get disappeared and appear again. It has to remain same without appearing and disappearing .)
How can show the icon in the taskbar without any flickering effect?
During traversing from back to next in middle I clicked cancel and the Cancel event is handled as follows,
void CFirstPage::OnCancel()
{
CDialog::EndDialog(TRUE);//For closing the dialog.
}
void CSecondPage::OnCancel()
{
CDialog::EndDialog(TRUE);//For closing the dialog.
}
Steps1:Click Next in the main dialog
Step2: Click Cancel in the second page
Now the application closes. But still instance is active in the "TaskManager". As per my understanding no instance should be alive once windows is closed ?
I suspect as the first dialog is only hidden not ended that instance is still existing in the TaskManager. Is this understanding correct?
How can I resolve this issue?
Can anyone kindly help me to resolve this issue.
As said by Iinspectable property sheets are best suited for your your problem statement.A very good example on how to use CPropertysheets can be found in codeproject
CProperty sheet example
Probably your main windows is still hidden after you end dialog with second page. Ending dialog of CSecondPage does not close application only closes active CSecondPage dialog.
Also OnCancel/OnOK does not need to be overriden if you just EndDialog with it. There is default behaviour implemented in OnCancel, which will close the dialog.
After secondPage.DoModal() show your main dialog again, or close it if that is the behaviour you want to achieve.
FirstPage isn't the original first dialog now, so you should store the first dialog object by yourself. You can do that like this:
void CFirstPage::OnBnNextButton()
{
::ShowWindow(this->GetSafeHwnd(),SW_HIDE);
CSecondPage secondDlg;
secondDlg.setFirstDialog(this); //customer function to store first dialig object
secondDlg.DoModal();
}
void CSecondPage::OnBnBackBtnClicked()
{
::ShowWindow(this->GetSafeHwnd(),SW_HIDE);
::ShowWindow(m_firstDialog->GetSafeHwnd(), SW_SHOW);
}

wxWidgets event focus textcontrol

I have another wxWidgets question regarding events and focus.
I have already looked at the tutorials and this old question here but I am still running into problems C++ Event (Focus) Handling
Basically I have a dialog with two wxTextCtrl elements and a Button.
What I would like to achieve is, that when I click on button it needs to tell me which of the two elements previously had the focus.
In the constructor of my Dialog I created all the elements and then connected them to the eventhandler like this: Ttop->Connect(TOP,wxEVT_KILL_FOCUS,(wxObjectEventFunction)&UI_ADDENTRY::hasfocus);
Tbottom->Connect(BOTTOM,wxEVT_KILL_FOCUS,(wxObjectEventFunction)&UI_ADDENTRY::hasfocus);
then there is the eventhandler that safes the id into focus
void UI_ADDENTRY::hasfocus(wxFocusEvent& event){
focus= event.GetId();
event.Skip();}
however when i try to access focus in the Button function it always tells me: 0 instead of TOP or BOTTOM / the ids that I gave the textcontrols
void UI_ADDENTRY::OnRecord(wxCommandEvent &event){
wxString tmp;
tmp << this->focus;
wxMessageBox(tmp);}
What am I doing wrong? is there another way of finding out which of the two textbox has been in focus last?
Thank you
The most fool proof way is to catch EVT_SET_FOCUS in your text controls and remember the last one that received it. This is not more difficult than what you are doing but should work without problems.
FWIW EVT_KILL_FOCUS can't, unfortunately, be consistently implemented on all platforms, in particular GTK+ doesn't give any information about the window focus is being lost to.
In think u mean event.GetWindow().GetId(). Though I'm not sure how ur casting from int to string.

Intercepting and Disabling Global Mouse Events

I have a problem with my mouse. Every now and then it will double click when I only single click. I know this is a problem with the mouse, and I've contacted the manufacturer, still waiting for a reply. But in the meantime I was wondering if there was a way that I could find out when the left mouse button had been clicked twice within a very short period (probably 1-10 milliseconds) of time, and disable the second click.
I mostly know how to use hooks, so that's not the problem, my main question is how to stop an event from happening, if that's possible.
The information on how to prevent the mouse message from being processed is in the documentation of the "LowLevelMouseProc callback function" in MSDN:
http://msdn.microsoft.com/en-us/library/windows/desktop/ms644986(v=vs.85).aspx
Specifically, it says: "If the hook procedure processed the message, it may return a nonzero value to prevent the system from passing the message to the rest of the hook chain or the target window procedure." So, if you know about windows hooks, you know how to do it.
EDIT: Actually, now that I think more about it, you don't want to discard any event. You simply want to transform the doubleclick event into just another left-button-down event. I believe you can do it from within the hook handler, and it will work. Have you tried it?
In C#'s WinForms, you write an event handler involving the mouse receiving a MouseEventArgs object. Inside it, you can access certain info such as the number of times it was clicked, for example.
protected void RowClicked(object sender, MouseEventArgs evt)
{
// Trigger it when the mouse was clicked only once
if( evt.Button.Clicks == 1 ) {
// ... more things ...
}
return;
}
Other GUI libraries have other possibilities. That said, your problem has nothing to do with GUI libraries. You have to change the sensitivity of your mouse, in the configuration options of your operating system. For example, in the Windows' control panel, you can change how much time has to pass between a click and another one to be considered a doble-click. In lUbuntu, you can do the very same, in System menu >> Preferences >> Keyboard and Mouse.

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