Re: How can I force the redraw of buttons which overlay a picture bitmap in a Dialog - C / C++ / MFC Discussion Boards

How can I force the redraw of buttons which overlay a picture bitmap in a Dialog

Neil Urquhart15-Sep-09 4:31

15-Sep-09 4:31

Using MFC Dialog App with VC6

I need some help to force redraw of buttons?

I have a bitmap image displayed in my dialog using the picture control and have positioned over the top of it number of CButton's (ie the buttons overlap the image). I want to get the buttons to remain displayed when I change the bitmap image in the button selected function.

If I have an "OnSel" function for each button with code like this :

void CDesignEditDlg::OnButtonSel3() <br />
{<br />
	// TODO: Add your control notification handler code here<br />
	MessageBox("Button 3 Pressed", "Select", MB_OK) ;<br />
	<br />
}

When I run the app and press a button it is all fine, ie I get the button pressed message pops up and all the buttons are still shown.

Since I want to change the image displayed while the button is pressed I tried to modify my code to something like this.

void CDesignEditDlg::OnButtonSel2() <br />
{<br />
	// TODO: Add your control notification handler code here<br />
	// Set new image<br />
	m_ctrlPageImage.SetBitmap(cBmp[1]);<br />
<br />
	MessageBox("Button 2 Pressed", "Select", MB_OK) ;<br />
<br />
	// Put old image back<br />
	m_ctrlPageImage.SetBitmap(cBmp[0]);<br />
}

This works in that it changes the displayed image while the popup message is on screen but all the buttons other than the one I pressed have disappeared.

Is there a way to force MFC to redraw my buttons over the top of the image after I have changed it ??

Re: How can I force the redraw of buttons which overlay a picture bitmap in a Dialog

Code-o-mat15-Sep-09 4:48

Code-o-mat

15-Sep-09 4:48

Try adding the WS_CLIPSIBLINGS[^] style to your picture control, maybe add WS_CLIPCHILDREN to the dialog itself. If all that doesn't help, try using RedrawWindow[^] on your buttons.

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Sometimes you just have to hate coding to do it well. <

Re: How can I force the redraw of buttons which overlay a picture bitmap in a Dialog

Neil Urquhart15-Sep-09 6:02

Neil Urquhart

15-Sep-09 6:02

Could'nt find WS_CLIPSIBLINGS as property to my Picture Control ! I tired setting WS_CLIPCHILDREN in the dialog, it had no effect.

RedrawWindow seems to be "half" working in that it is redrawing the buttons before my pop dialog displays. But after exiting the popup and reverting the image to the orignal bitmap the button redraw does not have any effect. ie After finishing the ButtonPressed func all the buttons have dissappeared again except the one I pressed.

Any more thoughts ?

My code is now like this in the button selection.

void CDesignEditDlg::ButtonPressed(int btn)<br />
{<br />
	m_ctrlPageImage.SetBitmap(cBmp[1]);<br />
<br />
	CButton* pImage ;<br />
	int b ;<br />
	for(b = 0 ; cButPos[b].id > 0 ; b++) {<br />
		// Move the button<br />
		pImage = (CButton*)GetDlgItem(cButPos[b].id);<br />
		pImage->RedrawWindow() ;<br />
	}<br />
<br />
	CColourFaderDlg dlg;<br />
	int nResponse = dlg.DoModal();<br />
	if (nResponse == IDOK)<br />
	{<br />
		// TODO: Place code here to handle when the dialog is<br />
		//  dismissed with OK<br />
	}<br />
	else if (nResponse == IDCANCEL)<br />
	{<br />
		// TODO: Place code here to handle when the dialog is<br />
		//  dismissed with Cancel<br />
	}<br />
<br />
	for(b = 0 ; cButPos[b].id > 0 ; b++) {<br />
		// Move the button<br />
		pImage = (CButton*)GetDlgItem(cButPos[b].id);<br />
		pImage->RedrawWindow() ;  // Seems to have no effect<br />
	}<br />
<br />
	m_ctrlPageImage.SetBitmap(cBmp[1]);<br />
}

Re: How can I force the redraw of buttons which overlay a picture bitmap in a Dialog

Neil Urquhart15-Sep-09 6:09

Neil Urquhart

15-Sep-09 6:09

Ignore pervious message, I goofed !!

I had the redraw of the buttons before changing the bitmap instead of after.

Re: How can I force the redraw of buttons which overlay a picture bitmap in a Dialog

Code-o-mat15-Sep-09 6:13

Code-o-mat

15-Sep-09 6:13

Use ModifyStyle[^] to add the WS_CLIPSIBLINGS style (piccontrol.ModifyStyle(0, WS_CLIPSIBLINGS);). If that still doesn't work, do the redrawing of the windows after you call SetBitmap on your picture control, not before it. Btw if i were you i would go another way with this, having overlapped controls on a dialog is imho nothing but trouble.

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Sometimes you just have to hate coding to do it well. <

Re: How can I force the redraw of buttons which overlay a picture bitmap in a Dialog [modified]

Moak15-Sep-09 14:09

Moak

15-Sep-09 14:09

Neil Urquhart wrote:
I have a bitmap image displayed in my dialog using the picture control and have positioned over the top of it number of CButton's (ie the buttons overlap the image). I want to get the buttons to remain displayed when I change the bitmap image in the button selected function.

Hi! I suggest to make the buttons child controls of the image. They have to be child controls, because overlapping siblings are poorly supported by Windows (see KB79981). Yes the MSDN article is one of the worst I have ever read and left me also confused the first time I read it. Even if you would manage to make overlapping controls work somehow else (e.g. by using transparency), you will sooner or later see redraw artefacts such as parts not been redrawn correctly.

Create your buttons as child controls from the start or use SetParent() in CDesignEditDlg::OnInitDialog().

Let me know if this works for you. Smile | :)

/M

[Edit: Fixed name of message handler and added some swearing]

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modified on Tuesday, September 15, 2009 8:32 PM

Re: How can I force the redraw of buttons which overlay a picture bitmap in a Dialog

Neil Urquhart15-Sep-09 20:04

Neil Urquhart

15-Sep-09 20:04

I tried using SetParent on all the buttons as below but now I don't see any buttons anywhere ! Did I miss something ? Do I need to set some extra things ?

BOOL CDesignEditDlg::OnInitDialog() <br />
{<br />
	CDialog::OnInitDialog();<br />
<br />
	<br />
	// TODO: Add extra initialization here<br />
	CWnd* pImage ;<br />
	WINDOWPLACEMENT wpImage ;<br />
	CRect rect;<br />
	CPoint imgPos ;<br />
<br />
	// Get the current top left position of the window<br />
	pImage = GetDlgItem(IDC_PAGEIMAGE) ;<br />
	pImage->GetWindowPlacement(&wpImage);<br />
	imgPos.x = wpImage.rcNormalPosition.left ;<br />
	imgPos.y = wpImage.rcNormalPosition.top ;<br />
<br />
	//pImage->ModifyStyle(0, WS_CLIPSIBLINGS);<br />
<br />
	int b ;<br />
	for(b = 0 ; cButPos[b].id > 0 ; b++) {<br />
		// Move the button<br />
		pImage = GetDlgItem(cButPos[b].id);<br />
		pImage->GetWindowRect(rect);<br />
		pImage->MoveWindow(imgPos.x + cButPos[b].x, imgPos.y + cButPos[b].y, rect.Width(), rect.Height(), TRUE);<br />
<br />
		// Make each CButton a child to CDesignEditDlg<br />
		pImage->SetParent(this) ;<br />
	}<br />
<br />
	<br />
	// Load the page images<br />
	cBmp[0].LoadBitmap(IDB_IMAGE0);	// This is the unselect version<br />
	cBmp[1].LoadBitmap(IDB_IMAGE1);<br />
/*	cBmp[2].LoadBitmap(IDB_IMAGE2);<br />
	cBmp[3].LoadBitmap(IDB_IMAGE3);<br />
	cBmp[4].LoadBitmap(IDB_IMAGE4);<br />
	cBmp[5].LoadBitmap(IDB_IMAGE5);<br />
	cBmp[6].LoadBitmap(IDB_IMAGE6);<br />
	cBmp[7].LoadBitmap(IDB_IMAGE7);<br />
	cBmp[8].LoadBitmap(IDB_IMAGE8);<br />
	cBmp[9].LoadBitmap(IDB_IMAGE9);<br />
	cBmp[10].LoadBitmap(IDB_IMAGE10);<br />
	cBmp[11].LoadBitmap(IDB_IMAGE11);<br />
	cBmp[12].LoadBitmap(IDB_IMAGE12);<br />
	cBmp[13].LoadBitmap(IDB_IMAGE13);<br />
	cBmp[14].LoadBitmap(IDB_IMAGE14);<br />
	cBmp[15].LoadBitmap(IDB_IMAGE15);<br />
	cBmp[16].LoadBitmap(IDB_IMAGE16);<br />
	cBmp[17].LoadBitmap(IDB_IMAGE17);<br />
	cBmp[18].LoadBitmap(IDB_IMAGE18);*/<br />
	<br />
	return TRUE;  // return TRUE unless you set the focus to a control<br />
	              // EXCEPTION: OCX Property Pages should return FALSE<br />
}

Re: How can I force the redraw of buttons which overlay a picture bitmap in a Dialog

Neil Urquhart15-Sep-09 20:57

Neil Urquhart

15-Sep-09 20:57

Ah ha !

Got it sussed. I should have used SetParent on the picture control and all its overlaping buttons to make them all children of the CDialog. I had to set the WS_CLIPCHILDREN/WS_CLIPSIBLINGS for the dialog/picture control to make it work. Without setting these properties the buttons don't display.

My code now looks like this with no "button redraw's" in the buttons select function.

BOOL CDesignEditDlg::OnInitDialog() 
{
	CDialog::OnInitDialog();

	
	// TODO: Add extra initialization here
	CWnd* pImage ;
	WINDOWPLACEMENT wpImage ;
	CRect rect;
	CPoint imgPos ;

	// Set CDesignEditDlg WS_CLIPCHILDREN
	ModifyStyle(0, WS_CLIPCHILDREN) ;

	// Get the current top left position of the picture control window
	pImage = GetDlgItem(IDC_PAGEIMAGE) ;
	pImage->GetWindowPlacement(&wpImage);
	imgPos.x = wpImage.rcNormalPosition.left ;
	imgPos.y = wpImage.rcNormalPosition.top ;

	// Set picture control WS_CLIPSIBLINGS
	pImage->ModifyStyle(0, WS_CLIPSIBLINGS);

	// Make picture control child to CDesignEditDlg
	pImage->SetParent(this) ;

	CWnd* pButton ;
	int b ;
	for(b = 0 ; cButPos[b].id > 0 ; b++) {
		// Move the button
		pButton = GetDlgItem(cButPos[b].id);
		pButton->GetWindowRect(rect);
		pButton->MoveWindow(imgPos.x + cButPos[b].x - (rect.Width()/2), imgPos.y + cButPos[b].y, rect.Width(), rect.Height(), TRUE);

		// Make each CButton a child to CDesignEditDlg
		pButton->SetParent(this) ;
	}

	
	// Load the page images
	cBmp[0].LoadBitmap(IDB_IMAGE0);	// This is the unselect version
	cBmp[1].LoadBitmap(IDB_IMAGE1);
/*	cBmp[2].LoadBitmap(IDB_IMAGE2);
	cBmp[3].LoadBitmap(IDB_IMAGE3);
	cBmp[4].LoadBitmap(IDB_IMAGE4);
	cBmp[5].LoadBitmap(IDB_IMAGE5);
	cBmp[6].LoadBitmap(IDB_IMAGE6);
	cBmp[7].LoadBitmap(IDB_IMAGE7);
	cBmp[8].LoadBitmap(IDB_IMAGE8);
	cBmp[9].LoadBitmap(IDB_IMAGE9);
	cBmp[10].LoadBitmap(IDB_IMAGE10);
	cBmp[11].LoadBitmap(IDB_IMAGE11);
	cBmp[12].LoadBitmap(IDB_IMAGE12);
	cBmp[13].LoadBitmap(IDB_IMAGE13);
	cBmp[14].LoadBitmap(IDB_IMAGE14);
	cBmp[15].LoadBitmap(IDB_IMAGE15);
	cBmp[16].LoadBitmap(IDB_IMAGE16);
	cBmp[17].LoadBitmap(IDB_IMAGE17);
	cBmp[18].LoadBitmap(IDB_IMAGE18);*/
	
	return TRUE;  // return TRUE unless you set the focus to a control
	              // EXCEPTION: OCX Property Pages should return FALSE
}



void CDesignEditDlg::ButtonPressed(int btn)
{
	// Set the selected button Image
	m_ctrlPageImage.SetBitmap(cBmp[1]);

/*	CButton* pImage ;
	int b ;
	for(b = 0 ; cButPos[b].id > 0 ; b++) {
		// Move the button
		pImage = (CButton*)GetDlgItem(cButPos[b].id);
		pImage->RedrawWindow() ;
	}*/

	CColourFaderDlg dlg;
	dlg.iFaderLineNo = btn ;
	int nResponse = dlg.DoModal();
	if (nResponse == IDOK)
	{
		// TODO: Place code here to handle when the dialog is
		//  dismissed with OK
	}
	else if (nResponse == IDCANCEL)
	{
		// TODO: Place code here to handle when the dialog is
		//  dismissed with Cancel
	}

	// Replace the original image
	m_ctrlPageImage.SetBitmap(cBmp[0]);

/*	for(b = 0 ; cButPos[b].id > 0 ; b++) {
		// Move the button
		pImage = (CButton*)GetDlgItem(cButPos[b].id);
		pImage->RedrawWindow() ;
	}*/

}


void CDesignEditDlg::OnButtonSel1() 
{
	// TODO: Add your control notification handler code here
	TRACE("Button 1\n") ;
	ButtonPressed(1) ;

}

Re: How can I force the redraw of buttons which overlay a picture bitmap in a Dialog

Moak15-Sep-09 23:21

Moak

15-Sep-09 23:21

Neil Urquhart wrote:
// Make each CButton a child to CDesignEditDlg
pButton->SetParent(this) ;

No, as I said make the buttons child controls of the image. In your code this would probably be pButton->SetParent(pImage) and you do not necessarily need WS_CLIPCHILDREN/WS_CLIPSIBLINGS in this case.

Here a visualisation of how the client-parent hierachy should look like:

dialog
  |_____image
  |       |_____button1 over image
  |       |_____button2 over image
  |       |_____button3 over image, etc
  |_____ other controls

Overlapping controls must not be siblings, hope this makes it more clear.

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Re: How can I force the redraw of buttons which overlay a picture bitmap in a Dialog

Neil Urquhart16-Sep-09 2:53

Neil Urquhart

16-Sep-09 2:53

I am afraid this doose not seem to work in that the buttons are displayed but when I click on the overlapped buttons nothing happens. I think the picture control is taking the input and not passing it onto the buttons.

My version that makes the picture control and buttons children of the dialog does work. Requires the WS_CLIPCHILDREN & WS_CLIPSIBLINGS properties also.

This is the code that does not work :

BOOL CDesignEditDlg::OnInitDialog() 
{
	CDialog::OnInitDialog();

	
	// TODO: Add extra initialization here
	CWnd* pImage ;
	WINDOWPLACEMENT wpImage ;
	CRect rect;
	CPoint imgPos ;

	// Set CDesignEditDlg WS_CLIPCHILDREN
	//ModifyStyle(0, WS_CLIPCHILDREN) ;

	// Get the current top left position of the picture control window
	pImage = GetDlgItem(IDC_PAGEIMAGE) ;
	pImage->GetWindowPlacement(&wpImage);
	imgPos.x = wpImage.rcNormalPosition.left ;
	imgPos.y = wpImage.rcNormalPosition.top ;

	// Set picture control WS_CLIPSIBLINGS
	//pImage->ModifyStyle(0, WS_CLIPSIBLINGS);

	// Make picture control child to CDesignEditDlg
	pImage->SetParent(this) ;

	CWnd* pButton ;
	int b ;
	for(b = 0 ; cButPos[b].id > 0 ; b++) {
		// Move the button
		pButton = GetDlgItem(cButPos[b].id);
		pButton->GetWindowRect(rect);
		pButton->MoveWindow(imgPos.x + cButPos[b].x - (rect.Width()/2), imgPos.y + cButPos[b].y, rect.Width(), rect.Height(), TRUE);

		// Make each CButton a child to CDesignEditDlg
		//pButton->SetParent(this) ;
		pButton->SetParent(pImage) ;
	}

This version of the code does work though!!

BOOL CDesignEditDlg::OnInitDialog() 
{
	CDialog::OnInitDialog();

	
	// TODO: Add extra initialization here
	CWnd* pImage ;
	WINDOWPLACEMENT wpImage ;
	CRect rect;
	CPoint imgPos ;

	// Set CDesignEditDlg WS_CLIPCHILDREN
	ModifyStyle(0, WS_CLIPCHILDREN) ;

	// Get the current top left position of the picture control window
	pImage = GetDlgItem(IDC_PAGEIMAGE) ;
	pImage->GetWindowPlacement(&wpImage);
	imgPos.x = wpImage.rcNormalPosition.left ;
	imgPos.y = wpImage.rcNormalPosition.top ;

	// Set picture control WS_CLIPSIBLINGS
	pImage->ModifyStyle(0, WS_CLIPSIBLINGS);

	// Make picture control child to CDesignEditDlg
	pImage->SetParent(this) ;

	CWnd* pButton ;
	int b ;
	for(b = 0 ; cButPos[b].id > 0 ; b++) {
		// Move the button
		pButton = GetDlgItem(cButPos[b].id);
		pButton->GetWindowRect(rect);
		pButton->MoveWindow(imgPos.x + cButPos[b].x - (rect.Width()/2), imgPos.y + cButPos[b].y, rect.Width(), rect.Height(), TRUE);

		// Make each CButton a child to CDesignEditDlg
		pButton->SetParent(this) ;
		//pButton->SetParent(pImage) ;
	}

Re: How can I force the redraw of buttons which overlay a picture bitmap in a Dialog

Moak16-Sep-09 3:19

Moak

16-Sep-09 3:19

Neil, are you sure the second example works reliable? I wonder because, it does nothing regarding client-parent hierachy, SetParent(this) in a dialog just sets the existing parent again.

If you want the dialog to receive notifications from the buttons use SetOwner(this) additional to SetParent(pImage). Alternatively, let the image control handle the button clicks.

Cheers
/M

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Re: How can I force the redraw of buttons which overlay a picture bitmap in a Dialog

Neil Urquhart16-Sep-09 3:56

Neil Urquhart

16-Sep-09 3:56

Second example is definatley the one that works !!

I tried again making buttons SetParent(pImage) and SetOwner(this) and still the buttons don't respond to clicks.

Re: How can I force the redraw of buttons which overlay a picture bitmap in a Dialog

Moak16-Sep-09 4:21

Moak

16-Sep-09 4:21

Please try the following: Show your dialog, take another window (e.g. Windows Explorer) and move it over your dialog a couple of times. Does the redrawing work as it should, image and buttons are visible?

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Re: How can I force the redraw of buttons which overlay a picture bitmap in a Dialog

Neil Urquhart16-Sep-09 4:41

Neil Urquhart

16-Sep-09 4:41

Works great !!

Re: How can I force the redraw of buttons which overlay a picture bitmap in a Dialog

Moak16-Sep-09 5:12

Moak

16-Sep-09 5:12

Great! If you see some painting problems in the future, feel free to post again. Smile | :)

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I want to know which os am using from C code.Is it is possible?

mohant$.net15-Sep-09 2:20

mohant$.net

15-Sep-09 2:20

Hi All,

I want to know which OS am using from C code.Is it is possible?.

Thanks

Mohan t

Re: I want to know which os am using from C code.Is it is possible?

David Crow15-Sep-09 2:36

David Crow

15-Sep-09 2:36

Have you looked at GetVersion()? (it's platform dependent)

"Old age is like a bank account. You withdraw later in life what you have deposited along the way." - Unknown

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

Re: I want to know which os am using from C code.Is it is possible?

CPallini15-Sep-09 2:46

CPallini

15-Sep-09 2:46

Does Linux provide that? Big Grin | :-D

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Re: I want to know which os am using from C code.Is it is possible?

mohant$.net15-Sep-09 3:17

mohant$.net

15-Sep-09 3:17

Actually i have created one dll USING Windows OS AND ONE MORE DLL USING Unix,so i want to know which dll created from which OS(from C programming).

Gimme an IDEA Frown | :(

.

Thanks,
Mohan.T

Mohan tC

Re: I want to know which os am using from C code.Is it is possible?

CPallini15-Sep-09 3:30

CPallini

15-Sep-09 3:30

Well, since you've already created the platform-independant code then both your dynamic libraries may provide a function, say tellMeTheOS().
Smile | :)

Re: I want to know which os am using from C code.Is it is possible?

Stuart Dootson15-Sep-09 7:07

Stuart Dootson

15-Sep-09 7:07

If you've used the right naming conventions, the Windows one will have a .dll extension, the Unix one a .so (for shared object) extension

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Re: I want to know which os am using from C code.Is it is possible?

Moak15-Sep-09 23:26

Moak

15-Sep-09 23:26

You can't. In your build system you need to handle this, for example on Windows you will build a DLL/LIB and on Linux a SO/A. Once you know on which target you are, you can find out on runtime which Windows version or Linux distibution the code runs on. So you will need specific C/C++ code for different platforms.

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Get pixel data from PBITMAPINFO struct?

Sauce!15-Sep-09 2:15

Sauce!

15-Sep-09 2:15

I'm capturing image data from a webcam using a simple class found here[^].

CVFWCapture cap;
PBITMAPINFO pBitmap = NULL;
ULONG BitmapSize;

if(!cap.Initialize())
{
	MessageBox(NULL, _T("Failed to initialise capture device. Terminating."), _T("Error!"), MB_OK);
	return 0;
}

//Capture an image from the capture device.
if(!cap.CaptureDIB(&pBitmap, 0, &BitmapSize))
{
	MessageBox(NULL, _T("Failed to capture image from device. Terminating."), _T("Error!"), MB_OK);
	return 0;
}
else
{
	//Do something with pixel data.
}

With the above code, I get a PBITMAPINFO structure which contains all the header data of the file, but there's no way for me to access the pixel data from this struct (obviously the struct is the header of a bmp file only). Is there a function I can use to get a pointer to the pixel data from this struct? From the way the class was advertised in the article, I was under the impression this class is used to capture image data - surely there isn't much use in only being able to access header info... Am I wrong or am I just missing something?

Re: Get pixel data from PBITMAPINFO struct? [modified]

CPallini15-Sep-09 2:31

CPallini

15-Sep-09 2:31

Sauce! wrote:
Is there a function I can use to get a pointer to the pixel data from this struct?

AFAIK no.

[added]
From a quick look at article source code, it looks like the pixel data section (after the CaptureDIB call) is in memory just after the BITMAPINFO struct (like bitmap files).
[/added]

Smile | :)

modified on Tuesday, September 15, 2009 8:39 AM

Re: Get pixel data from PBITMAPINFO struct?

Sauce!15-Sep-09 2:58

Sauce!

15-Sep-09 2:58

In that case, does anybody know of any existing libraries that will allow me to simply capture pixel data from a video device?

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