Getting Resource Id from dialog Item - c++

I put a picture control to a dialog, and did this settings
Misc->Type->Bitmap
Misc->Image->999
now in the OnInitDialog function of the dialog, I catched CWnd* of the picture control and I want to obtain a handle to either image I assign to the controller or image's id (which is 999)
How can I do this ?
thank you for your help.
CONTROL 65443, IDC_TRUSS_CTRL, "Static", SS_BITMAP, 13, 13, 517, 212
to be more precise about the problem, I want the number 65443 I've got the dialog's handle which holds this control and I also got the handle of the IDC_TRUSS_CTRL
what I do is:
bool error;
dialogWnd->GetDlgItemInt(controlWnd->GetDlgCtrlID(), &error, 0);
however error is 0 which means it encounter an error :\

You can get a CBitmap pointer from the control casting to a CStatic instead of CWnd:
CStatic *pPictureCtrl = (CStatic*)GetDlgItem( PICTURE_CONTROL_ID ); //Notice is the control resources ID not the Image resources ID
CBitmap *pBitmap = pPictureCtrl->GetBitmap();
But this won't be of much help depending on what you want to do with it (?).

Related

C++ Add A Bitmap from resource to Picture Control

i want to display a bitmap on my Picture control,
but actually no matter what Im trying, it doesnt work.
Right now my method looks like this:
SendDlgItemMessage(hWnd ,picture_CTRL, BM_SETIMAGE , IMAGE_BITMAP, (LPARAM) MAKEINTRESOURCE(IDB_BITMAP1));
I have also already tried to use the
STM_SETIMAGE
Message, but it wont work as well.
My Picture Control property "Type" is set to "Bitmap" and my Bitmap has an ID in resource.h
Hope you guys can help :)
First, you can't just mix and match messages in standard Windows controls. BM_SETIMAGE and STM_SETIMAGE have completely different values. If you are using a Static control, use STM_SETIMAGE. If you are using a Button control, use BM_SETIMAGE.
Second, the documentation for STM_SETIMAGE says that the LPARAM must be a handle to the image. You are passing a resource ID. You need to get the handle by calling LoadImage first. For example:
HBITMAP hBitmap = reinterpret_cast<HBITMAP>(LoadImage(
GetModuleHandle(NULL),
MAKEINTRESOURCE(IDB_BITMAP1),
IMAGE_BITMAP,
0,
0,
0));
SendDlgItemMessage(
hWnd,
picture_CTRL,
STM_SETIMAGE,
IMAGE_BITMAP,
reinterpret_cast<LPARAM>(hBitmap));
Note that according to the documentation you are responsible for deleting the bitmap when you are done with it.
EDITS: Note that I had two problems in my original version of the code, both caused by copying and pasting from the question. I failed to pass the handle as the LPARAM myself and I used BM_SETIMAGE instead of STM_SETIMAGE. I will also add a note in the answer that, as Cody Gray pointed out, the MSDN documentation for a function or message will tell you whether you can use MAKEINTRESOURCE.

GetDlgItemInt returns 0

I have a dialog and a picture control inside of it. During OnInitDialog I try to obtain the text part of the picture control like this
CWnd *dialogHandle; // Handle of the dialog
CWnd *itemHandle; // Handle of the picture control
BOOL error;
dialogHandle->GetDlgItemInt(itemHandle->GetDlgCtrlID(), &error, 0);
however GetDlgItemInt function set error to 0 which says there is an error
here is the resource line
CONTROL 65443, IDC_PICTURE, "Static", SS_BITMAP, 13, 13, 40, 40
I want this number 65443
You want GetWindowLong(hWnd, GWL_ID); (or the MFC equivalent).
GetDlgItemInt() is simply an atoi() wrapper around GetDlgItemText(), which reads the label of the control, not its ID.
GetDlgItemInt() is supposed to get a text out of control. The second parameter is referred to as 'translated' flag and not an 'error' flag. Is this realy the method you are looking for? I think you need something else.

How can I change the default CDialog font for a non-modal dialog?

It is necessary to switch off the "ClearType" property of the default font for all dialog controls. It is possible to do that for one control by setting
logfont.lfQuality = ANTIALIASED_QUALITY
There are a lot of suggestion how to do the same for modal dialogs (http://neelaakash.wordpress.com/2007/12/31/change-default-dialog-font-of-cdialog/ and others), but that should be done for non-modal dialogs (are instantiated with new and Create(...) methods). I've tried to do that myself:
Override 'Create' method, and modify dialog template:
BOOL CActivationChildDialogLicenseInfo::Create(UINT nIDTemplate,
CWnd* pParentWnd)
{
CDialogTemplate dlt;
int nResult;
// load dialog template
if (!dlt.Load(MAKEINTRESOURCE(nIDTemplate))) return -1;
// set your own font, for example “Arial”, 10 pts.
dlt.SetFont(L"Arial", 12);
// get pointer to the modified dialog template
LPSTR pdata = (LPSTR)GlobalLock(dlt.m_hTemplate);
// let MFC know that you are using your own template
m_lpszTemplateName = NULL;
InitModalIndirect(pdata);
// display dialog box
nResult = CActivationChildDialog::Create(nIDTemplate, pParentWnd);
// unlock memory object
GlobalUnlock(dlt.m_hTemplate);
return nResult ;
}
Seems like this method do nothing (it is called, I've checked that with putting break-point inside).
I've tried to call
nResult = CActivationChildDialog::Create(NULL, pParentWnd);
...but got a lot of ASSERTs.
I've also tried to override the 'OnSetFont' method:
void CActivationChildDialogLicenseInfo::OnSetFont(CFont *pFont)
{
CActivationChildDialog::OnSetFont(pFont);
LOGFONT logfont;
pFont->GetLogFont(&logfont);
LOGFONT logfont2=logfont;
pFont->DeleteObject();
logfont2.lfItalic = true;
logfont2.lfQuality = ANTIALIASED_QUALITY;
pFont->CreateFontIndirect(&logfont2);
}
That causes ASSERT during run-time and resulted in a VERY big font being used (lost default font settings, doesn't accept new specified settings)... I don't know why.
Please advise, how can I change a default dialog font that will be "inherited" by all dialog controls?
Thank you very much.
First off: the simple, reliable way to do this is to create the dialog and then send WM_SETFONT (or call SetFont()) to the dialog and each control in it. I'll show you how to do that below, but first, here's why the two strategies you've already tried didn't (and can't) work:
Modifying the dialog template
First off, you should be calling CDialog::CreateIndirect() if you wish to use a dialog template that you've already loaded.
But don't bother. The dialog template contains only the face name and point size - it does not allow you to specify other LOGFONT values such as lfQuality. If it did, you could simply specify that in your resource definition and avoid writing any runtime code at all!
Intercepting WM_SETFONT
In theory, you could make this work. But it's not practical. Your code has several problems: first off, you'd have to intercept this message for every child control in order for it to do anything useful: the dialog itself probably doesn't render any text. But worse, you're passing the original font to the base class (which hands it to the default window procedure, which stores it internally for later use) and then immediately destroying it - this means the dialog (and everything else using that font, including all of the child controls) will be trying to draw text using a bogus font, and reverting to the default font as a result. Finally, you're creating a new font attached to a temporary object (pFont) created and destroyed by MFC - internally, the CFont object you're working with will be detached from the font handle and destroyed, leaking a handle to a font object that nothing uses.
Leaky abstractions: a note on HFONT and CFont
HFONT is a handle type that Windows uses to represent a font object. Like most of GDI, there are specific functions for creating fonts, and the general-purpose DeleteObject() function for destroying them.
CFont is a light-weight wrapper class for HFONTs. A CFont instance can be attached and detached from an existing HFONT, or used to create a new one. If a CFont instance is still attached to a HFONT when its deconstructor executes, it will call DeleteObject() to destroy the underlying object. Internally, MFC utilizes temporary CFont instances that are attached and detached from HFONTs when calling various message handlers (such as OnSetFont). It's worth remembering that internally, Windows knows nothing about CFont, and a single HFONT may belong to 0 or more CFont instances at any given point in time.
A note on fonts and WM_SETFONT
When you create a new font - whether or not it is wrapped in a CFont object - you are the owner of that font, and it is your responsibility to destroy it once you are finished using it. Passing it to WM_SETFONT (CWnd::SetFont()) doesn't change ownership! This is actually quite useful, as it allows you to pass the same font to multiple windows without worrying about which one will destroy it - you're still the owner, and so you can (and must) destroy it yourself (once there are no windows still using it).
Finally - how to quickly create and set a font on a dialog and all its children
So you should now have enough background to understand the necessary steps:
Create the dialog
Create the desired font
Pass the font to the dialog and its children (by either sending WM_SETFONT messages, or by calling CWnd::SetFont... which itself send a WM_SETFONT message).
When the dialog is destroyed, also destroy your font.
Example
// define this as a class member - class destructor then handles step four!
CFont m_nonCleartypeFont;
BOOL CActivationChildDialogLicenseInfo::Create(UINT nIDTemplate,
CWnd* pParentWnd)
{
// step one: create dialog normally
BOOL nResult = CActivationChildDialog::Create(nIDTemplate, pParentWnd);
// step two: create custom font
// relying on destructor to destroy font once we're done with it
// so be careful to only create it once!
if ( NULL == m_nonCleartypeFont.m_hObject )
{
CFont* pOriginalFont = GetFont(); // use template font as... template!
// pull information from original font
LOGFONT logfont;
pOriginalFont->GetLogFont(&logfont);
// make font adjustments:
// specify italics
logfont.lfItalic = true;
// and non-cleartype antialiasing
logfont.lfQuality = ANTIALIASED_QUALITY;
// create our font based on adjusted information
m_nonCleartypeFont.CreateFontIndirect(&logfont);
}
// step three: set our custom font on the dialog and all children
SetFont(&m_nonCleartypeFont, FALSE);
// Send message to quickly set this font for all children.
// See documentation for SendMessageToDescendants()
// - this is actually the example given!
SendMessageToDescendants(WM_SETFONT,
(WPARAM)m_nonCleartypeFont.m_hObject,
MAKELONG(FALSE, 0),
FALSE);
return nResult;
}

How to create controls at runtime?

How to create dynamic MFC controls and handle message maps of the controls at runtime?
It really depends on which controls do you want to create, especially if you want to know which flags should you set. In general it goes down to this:
Normally a CWnd-derived control is created using Create or CreateEx. For a CButton, for instance:
CButton button;
button.Create("Button text", WS_CHILD | WS_VISIBLE | WS_TABSTOP | BS_PUSHBUTTON | DT_CENTER, CRect(5, 5, 55, 19), this, nID);
where the CRect specifies the button position, this is a pointer to the parent window, and nID is the control ID.
If the control doesn't come out as expected, it's probably because some flags are missing. I suggest you draw a sample control in design mode, check out the code for that control in the RC file, and copy the flags to the Create caller.
As for the message maps, they are normally routed to the parent window. The nID value you used in Create is important here, because it will be the number that identifies the control in the message map. If you have a fixed number of controls, you can hard-code the nID numbers for your controls (starting at 10000, for instance); if not, you'll have to provide a way for the parent window to identify them. Then you just add the message map entries.
ON_BN_CLICKED(10000, OnBnClicked)
ON_CONTROL_RANGE(BN_CLICKED, 10010, 10020, OnBtnsClicked)
You can use the ON_CONTROL_RANGE message map to map a range of IDs to the same function.

create a control programmatically using MFC

I just wonder how to do it.
I write :
CEdit m_wndEdit;
and in the button event handler (dialog app),
I write :
m_wndEdit.Create(//with params);
but I still don't see the control appear in the UI.
I actually wrote this in the button handler :
CWnd* pWnd = GetDlgItem(IDC_LIST1);
CRect rect;
pWnd->GetClientRect(&rect);
//pWnd->CalcWindowRect(rect,CWnd::adjustBorder);
wnd_Edit.Create(ES_MULTILINE | ES_NOHIDESEL | ES_READONLY,rect,this,105);
wnd_Edit.ShowWindow(SW_SHOW);
this->Invalidate();
id 105 doesn't exist. (I used it in the Create member function of CEdit). I just put it in there. isn't it supposed to be the id you want to give to the new control ? Should it already exist ?
Check with the following set of flags as the example mentioned in MSDN:
pEdit->Create(ES_MULTILINE | WS_CHILD | WS_VISIBLE | WS_TABSTOP | WS_BORDER | ES_NOHIDESEL | ES_READONLY,
rect, this, 105);
The Invalidate() is not necessary
Add the WS_VISIBLE flag to your create flags, you don't need the ShowWindow
You are creating the button on the location where IDC_LIST1 is - you probably want to do pWdn->Destroy() after the GetClientRect()
The id you pass to Create() can be anything, of course if you want to handle messages from this button later you'll need to use the correct id. In that case it's easiest to manually add an entry to resource.h.
What do you mean with 'I put this code in the button event handler' - which button? A different one from the one you're trying to create, I may hope? Does your code get called at all, does it stop when you put a breakpoint in? What's the value of wnd_Edit->m_hWnd after the call to Create()?
wnd_Edit is a member of your dialog, right, and not a a function local variable?
What is wnd_Edit exactly? If it's a local variable in that function, that is likely the problem. The CWnd destructor destroys the window associated with the CWnd. So when wnd_Edit goes out of scope, the edit box is destroyed too.
If that's not it, check the return value of Create(). Is it NULL? If it is, check the value of GetLastError().