Getting the menu handle - winapi

I created menus and sub menus using the resource editor in visual studio. I now want to add items to one of the menus during run time. I was going to use the InsertMenuItem function but I don't know how to get access to the HMENU variable.

LoadMenu seems is what you need. Use it to load menu from resource editor, something like this:
HMENU yourMenu = LoadMenu( hInst, // variable where you stored your HINSTANCE
MAKEINTRESOURCE(IDM_MENU1) ); // replace IDM_MENU1 with the ID of your menu
Here are lots of useful examples, you may find very useful. Some of them address your issue, and some might be useful to you in the future. I would study the Example of Menu-Item Bitmaps section if I were you...
If you need a menu handle that is already assigned to a window then use GetMenu as member arx said. Something like this:
HMENU yourMenu = GetMenu(hWnd); // hWnd is the HWND of the window that owns your menu
Do not forget to destroy the menu when it is no longer needed ( usually upon window destruction ) with DestroyMenu.
This example might help you as well. This is very good introductory tutorial for Win32, I suggest you to read it ( just go to the home page and download both PDF and .zip file with code examples ).
As I have said before, your question is not entirely clear, so if you have further questions leave me a comment.
Hopefully this answer solved your problems. Best regards.

Related

Win32 custom message box

I want to make a custom message box. What I want to customize is the button's text.
MessageBoxW(
NULL,
L"Target folder already exists. Do you want to overwrite the folder?",
L"No title",
MB_YESNOCANCEL | MB_ICONQUESTION
);
I'd like to just change the buttons text to Overwrite, Skip, Cancel.
What's the most simple way?
I have to make this as having same look and feel with Windows default messagebox.
As said by others, a typical way is to create a dialog resource and have a completely independent dialog, which GUI you need to design in the way that it looks like standard dialog (to meet your request for feel and look). If you want to accept text messages, you might probably need to add code which resizes the window appropriately.
Still, there is another option for those who feel like diving into advanced things. While MessageBox API does not offer much for fint tuning, you still have SetWindowsHookEx in your hands. Having registgered the hook, you can intercept standard MessageBox window procedure and subclass it in the way you like.
Typical things include:
changing button text
adding more controls
adding timed automatic close
Hooking standard window can do all of those.
UPD. Hey, I realized I have some code with SetWindowsHookEx to share: http://alax.info/blog/127
You could create an own dialog. Or you could use a window hook as described in this article.
An archived version of the article can be found on web.archive.com.
Make a dialog resource (with a GUI editor, or by hand) and call DialogBox on it. There's no way to alter MessageBox behaviour, other than what's supported by its arguments.
That said, your message box can very well use stock Yes/No options.
The task dialog functionality introduced in Vista does exactly what you want and follows the prevailing system theme. However, if you have to support XP, then this will be of little comfort to you.
I know this question is old, but I just stumbled upon it now.
I would like to expand the other answers in regards to using a TaskDialog instead of a MessageBox. Here's a concise example of using a TaskDialog to do precisely what was asked; change the button's texts:
const TASKDIALOG_BUTTON buttons[] = { {IDYES, L"Overwrite"}, {IDNO, L"Skip"}, {IDCANCEL, L"Cancel"} };
TASKDIALOGCONFIG taskDialogConfig = {
.cbSize = sizeof(TASKDIALOGCONFIG),
.pszMainIcon = TD_WARNING_ICON, // TaskDialog does not support a question icon; see below
.pButtons = buttons,
.cButtons = ARRAYSIZE(buttons),
.pszWindowTitle = L"No title",
.pszContent = L"Target folder already exists. Do you want to overwrite the folder?"
};
TaskDialogIndirect(&taskDialogConfig, NULL, NULL, NULL);
Some noteworthy things:
You need to use TaskDialogIndirect, not the basic TaskDialog function
when not specifying a parent window, the icon specified in pszMainIcon is displayed in the title bar as well
There is no equivalent to the MessageBox's MB_ICONQUESTION, quoting a quote from this forumpost: Don't use the question mark icon to ask questions. Again, use the question mark icon only for Help entry points. There is no need to ask questions using the question mark icon anyway—it's sufficient to present a main instruction as a question.
checking which button was selected would have to be done by passing a pointer to an int as the second argument of TaskDialogIndirect and checking its value on return (the documentation should be pretty clear)
Here is a small open source library that allows you to customize Message Boxes. Developed by Hans Ditrich.
I have successfully used it in another POC that allows embedding a custom icon in such MessageBox that can be called even from a Console application.
I should also point to the Task Dialog. Here is an example of using it:
int nButtonPressed = 0;
TaskDialog(NULL, hInst,
MAKEINTRESOURCE(IDS_APPLICATION_TITLE),
MAKEINTRESOURCE(IDS_DOSOMETHING),
MAKEINTRESOURCE(IDS_SOMECONTENT),
TDCBF_OK_BUTTON | TDCBF_CANCEL_BUTTON,
TD_WARNING_ICON,
&nButtonPressed);
if (IDOK == nButtonPressed)
{
// OK button pressed
}
else if (IDCANCEL == nButtonPressed)
{
// Cancel pressed
}

Big problems with MFC/WinAPI

I need to create a SDI form with a formview that has two tabs, which encapsulate multiple dialogs as the tab content. But the form has to have a colored background.
And things like these makes me hate programming.
First, I tried CTabControl, via resource editor, tried different things, but the undocumented behavior and the quirks with no answers led me into a roadblock.
After many hours of searching, I found that there is a control called property sheet, which is actually what I need.
Some more searching later, I found that property sheet can even be actually embedded onto CFormView like so: http://www.codeguru.com/Cpp/controls/propertysheet/article.php/c591
And that the dialog classes derived from CPropertyPage can be directly added as pages via AddPage method of CPropertySheet.
Great! Not quite so... Some of the controls didn't worked, and were not created, ran into weird asserts. Turns out the DS_CONTROL style was missing from the dialogs. Found it completely accidentaly on Link, no word about that on MSDN!!!! Property page must have: DS_3DLOOK | DS_CONTROL | WS_CHILD | WS_TABSTOP, and can have: DS_SHELLFONT | DS_LOCALEDIT | WS_CLIPCHILDREN styles! Not any other, which are created by default with resource editor. Sweet, super hidden information for software developers!
The quote in comments on that page: "OMG. That's where that behavior came from...
It turns out that the PlaySound API relied on that behavior when playing sounds on 64bit machines." by Larry Osterman, who as I understand works for Microsoft for 20 years, got me laughing out loud.
Anyway, fixed that, the dialog-controls(CPropertyPages) are created as expected now, and that part looks something remotely promising, but the next part with color is dead end again!
Normally you override WM_CTLCOLOR, check for control ID or hwnd and supply the necessary brush to set the color you need. Not quite so with CPropertySheet, the whole top row stays gray! For CTabCtrl it somehow works, for CPropertySheet it doesn't.
Why? Seems that the CPropertySheet is kinda embedded inside CTabControl or something, because if I override WM_ERASEBKGND, only the internal part changes the color.
Now it seems that there is a GetTabControl() method in the CPropertySheet, that returns the actual CTabCtrl* of the CPropertySheet. But since it's constructed internally, I can't find how to override it's WM_CTLCOLOR message processing.
There seems to be a way to subclass the windowproc, but after multiple tries I can't find any good source on how to do it. SubclassWindow doc on MSDN says: "The window must not already be attached to an MFC object when this function is called."?! What's that?
I tried creating a custom CCustomTabCtrl class based on CTabCtrl via MFC wizard, created an instance of it, called SubclassWindow from one of the CCustomPropertySheet handlers to override the internal CTabCtrl, but nothing works, mystical crashes deep inside MFC.
Tried setting WindowLong with GCL_HBRBACKGROUND for the internal CTabCtrl, nothing changed.
And worst of all, I can't find any sort of useful documentation or tutorials on the topic.
Most I can find is how to ownerdraw the tab control, but this is seriously wrong on so many ways, I want a standard control behavior minus background color, I don't want to support different color schemes, windows versions, IAccesible interfaces and all this stuff, and none of the ownerdraw samples I've seen can get even 10% of all the standard control behavior right. I have no illusion that I will create something better, I wont with the resources at hand.
I stumbled upon this thread, and I can't agree with the author more: http://arstechnica.com/civis/viewtopic.php?f=20&t=169886&sid=aad002424e80121e514548d428cf09c6 owner draw controls are undocumented PITA, that are impossible to do right, and there is NULL information on MSDN to help.
So is there anything I have missed or haven't tried yet? How to change the top strip background color of the CPropertySheet? Anyone?
Your only option is to ownerdraw the tab control. It's not that hard. Well, it is frustrating because MFC doesn't tell you how to make the necessary Win32 calls.
In your CPropertySheet-derived class, overwrite OnInitDialog() and add:
GetTabControl()->ModifyStyle(0,TCS_OWNERDRAWFIXED);
This puts your CPropertySheet-derived class in charge of drawing the tab control. Add a handler for WM_DRAWITEM (OnDrawItem) and change backgroundColor and textColor to match whatever colors you wanted. Code for OnDrawItem follows:
void CPropSht::OnDrawItem(int nIDCtl, LPDRAWITEMSTRUCT lpDrawItemStruct)
{
if (ODT_TAB != lpDrawItemStruct->CtlType)
{
CPropertySheet::OnDrawItem(nIDCtl, lpDrawItemStruct);
return;
}
// prepare to draw the tab control
COLORREF backgroundColor = RGB(0,255,0);
COLORREF textColor = RGB(0,0,255);
CTabCtrl *c_Tab = GetTabControl();
// Get the current tab item text.
TCHAR buffer[256] = {0};
TC_ITEM tcItem;
tcItem.pszText = buffer;
tcItem.cchTextMax = 256;
tcItem.mask = TCIF_TEXT;
if (!c_Tab->GetItem(c_Tab->GetCurSel(), &tcItem )) return;
// draw it
CDC aDC;
aDC.Attach(lpDrawItemStruct->hDC);
int nSavedDC = aDC.SaveDC();
CBrush newBrush;
newBrush.CreateSolidBrush(backgroundColor);
aDC.SelectObject(&newBrush);
aDC.FillRect(&lpDrawItemStruct->rcItem, &newBrush);
aDC.SetBkMode(TRANSPARENT);
aDC.SetTextColor(textColor);
aDC.DrawText(tcItem.pszText, &lpDrawItemStruct->rcItem, DT_CENTER|DT_VCENTER|DT_SINGLELINE);
aDC.RestoreDC(nSavedDC);
aDC.Detach();
}
Thank you for this solution but...
The above solution works well with one tab, but when you have multiple tabs it seems rename the wrong tabs. I needed to change the if statement for GetItem to:
if (!c_Tab->GetItem(lpDrawItemStruct->itemID, &tcItem )) return;
Needed lpDrawItemStruct->itemID to get the tabs named correctly

Determine if a menu is dropped down

Is there a way to determine if a menu is dropped down in the win32 api? Something that could be used like so:
HMENU hMenu = GetMenu(hWnd);
HMENU hSubMenu = GetSubMenu(hMenu);
// Is hSubMenu dropped down?
I'm not sure of a way to operate specifically on HMENUs to see if the menu is showing (and a quick scan of the platform SDK docs didn't turn up anything specific), but you might be able to use the GetMenuItemInfo function to get a MENUITEMINFO struct relating to the menu item which owns the dropdown. If the fState member has MFS_HILITE set, that should indicate that the item is selected and the sub menu is most likely open. Correctness isn't guaranteed on my part but it's worth experimenting with.
Another possible option would be using FindWindow with the class "#32768" to find the hWnd of whatever menus may be open, and sending the MN_GETHMENU message to whichever windows you find to retrieve the HMENU and compare it to the expected value from GetSubMenu.

Changing Win32 menu colors

Is there a way to change the colors used by plain Win32 menus (background, text, and highlight) for a single process, without using SetSysColors?
(SetSysColors does a global change, which is bad, and if you crash or forget to set the colors back with SetSysColors again before exiting, they will not be restored until you logout.)
The SetMenuInfo() API is your friend. It lets you apply any brush to paint your menu's background.
Something along these lines should solve your problem:
MENUINFO mi = { 0 };
mi.cbSize = sizeof(mi);
mi.fMask = MIM_BACKGROUND|MIM_APPLYTOSUBMENUS;
mi.hbrBack = hBrush;
HMENU hMenu = ::GetMenu(hWnd);
SetMenuInfo(hMenu, &mi);
If I believe your comment to Rob, it is for a skinned application, with special look and feel. So the way to go is probably indeed, as ferek points out (in an unfriendly way...) to use owner-drawn menus: you will be able to define precisely their look.
I have to ask, why? Adopting the regular Windows look-and-feel is good; it means users can be confident that there are consistent elements in your user interface, onto which they can map their experience using other software for the platform.
[I'm probably preaching to the converted, of course, but I thought I'd make the point so anyone who reads an answer for this doesn't start making all their menus sky-blue-pink 'cause it looks pretty.]

Win32 window Owner vs window Parent?

In Win32 programming, what is the difference between a window's parent and a window's owner? I thought I had it figured out, then I came across this code:
SetWindowLong(handle, GWL_HWNDPARENT, foo);
This actually sets the window's owner, not the parent - despite the GWL_HWNDPARENT being used. Are the terms parent/owner interchangeable, or is there actually a difference?
Ownership is a relationship between two top level windows while Parent is a relationship between a top level and a WS_CHILD, or a WS_CHILD and another WS_CHILD.
The parent of a button is the form it is on, while a message box is owned by the form that showed it.
Read this article from Microsoft Win32 Window Hierarchy and Styles to get a much clearer understanding of Ownership, Parenting, ZOrder, SetWindowLong, GetWindow and all the other nasty bits of the Win32 api for creating window relationships.
EDIT: Looks like Microsoft took down that content, here is another reasonable summary of Ownership / Parenting.
Owner is the Window* responsible for a control or dialog (for example, responsible for creating/destroying the window).
Parent is the next-senior window* to a control or dialog in the window chain, but isn't actually responsible for it (doesn't necessarily care about its lifecycle, etc). A window's parent can also be its owner.
*Window vs window: Window is an actual window displayed on the screen; window is any object with a HWND (includes buttons, panels, etc).
Chen's blog post is the one to read. The key point for me is that the WS_CHILD style must be used on the child window. You can attempt to create a child window and pass the parent handle in to CreateWindow( ), but if you don't have the WS_CHILD style set the two windows will have the owner relationship, not the parent/child relationship.
It's super easy: the code is wrong. End of story right here.
Yes, some windows may happen to react favorably to such a call - someone not knowing any better may have implemented support for it. Quoth documentation (and it's old documentation) - You must not call SetWindowLong with the GWL_HWNDPARENT index to change the parent of a child window. Instead, use the SetParent function.
So, all there's to it: you came upon buggy code, change it to SetParent or refactor to do something else, and keep going?

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