Never-ending WM_PAINT messages!!? - C / C++ / MFC Discussion Boards

Carlos Antollini7-Dec-01 2:25

7-Dec-01 2:25

John, you can see in the MSJ January 2000. I that isue paul Dilascia, shown how implement a CHTMLView in a Dialog Box, if you read that article you will can implement a CView Class in a Dialog.

I hope to Help...

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Today is Friday!!!! Beer | [beer]

Free for all CP!!!!

Carlos Antollini.
Sonork ID 100.10529 cantollini

Re: CView in a Dialog box

Lars Dirks7-Dec-01 1:33

Lars Dirks

7-Dec-01 1:33

Yes, I have used a treecontrol, and subclassed it to my own view derived from CScrollView, By using a treecontrol, you don't have to worry about not getting all mouse actions and things like that.

So yes it can be done!

Re: CView in a Dialog box

#realJSOP7-Dec-01 1:49

#realJSOP

7-Dec-01 1:49

Can you possibly provide some sample code? Smile | :)

I tried the article mentioned above and it asserts in wincore.

"...the staggering layers of obscenity in your statement make it a work of art on so many levels." - Jason Jystad, 10/26/2001

Re: CView in a Dialog box

Giles7-Dec-01 2:59

Giles

7-Dec-01 2:59

Hi John,

In an app I am currently working on which is MDI, I wanted each MDI View to be a CFormView with a dialog resource. The problem I had was making the window look like a dialog box. I was trying to port the look and functionality of an Access form into an MDI arcitecture.

I had to modify the CChildFrame and the main CFormView derived classes.

If this sounds like what your looking for I can send you the sample code.

Giles

Re: CView in a Dialog box

#realJSOP7-Dec-01 3:14

#realJSOP

7-Dec-01 3:14

Actually, all I need is a place to draw some stuff (using GDI calls and such). It doesn't have to scroll, it doesn't need to respond to mouse clicks, it doesn't even need to open a document. I think I'll try just creating a CWnd and attaching it to the dialog somehow.

I figured using a CView would be easier, but it's been a pain in the ass.

Let's also not forget that this is a dialog-based app where I did not elect to support doc/view. Smile | :)

"...the staggering layers of obscenity in your statement make it a work of art on so many levels." - Jason Jystad, 10/26/2001

Propertysheet of ActiveX

Mazdak6-Dec-01 7:15

Mazdak

6-Dec-01 7:15

I wrote ActiveX with ATL,I add background color
property when I insert control into project,How can I add
property sheet,for this stock property?

Re: Propertysheet of ActiveX

J Patel7-Dec-01 11:38

J Patel

7-Dec-01 11:38

Try adding

PROP_ENTRY("BackColor", DISPID_BACKCOLOR, CLSID_StockColorPage)

in between your BEGIN_PROP_MAP and END_PROP_MAP in your header file.

HTH

Jignesh

Never-ending WM_PAINT messages!!?

Jamie Hale6-Dec-01 5:30

Jamie Hale

6-Dec-01 5:30

I have several applications that use custom CWnd controls. And for some reason, when I use GetDC() and ReleaseDC() while handling a WM_PAINT message, as soon as OnPaint() is done, it gets called again. This craziness seems to go away when I use a local CPaintDC.

Trouble is, I'm now trying to fix an old app that uses a seperate thread to handle the drawing. OnPaint() puts a custom PAINT message in a queue for the thread, which in turn uses GetDC() on a hWnd (GetSafeHwnd()). I can't seem to construct a CPaintDC without MFC ASSERTing that the CWnd is invalid.

void OnPaint() {
  queue.PushEvent(PAINT, currentRange);
}

int ThreadProc(CWnd *pWnd) {
  while(1) {
    t = queue.PopEvent();
    switch(t) {
      case PAINT:
        HWND hWnd = pWnd->GetSafeHwnd();
        HDC hDC = GetDC(hWnd);
        CDC *pDC = CDC::FromHandle(hDC);
        ...
        ReleaseDC(hWnd, hDC);
        break;
      ...
    }
  }
}

When I try CPaintDC dc(pWnd), it ASSERTs.

So...

Q1) Has anyone else ever seen the never-ending stream of WM_PAINT messages? And if so, any idea how to prevent it?

Q2) Can anyone come up with a nice way of creating a CPaintDC from a CWnd inside a thread? I can't easily (and safely) create the DC outside the thread and pass it in.

J

Fixed it I think...

Jamie Hale6-Dec-01 6:42

Jamie Hale

6-Dec-01 6:42

Found CWnd::BeginPaint() and CWnd::EndPaint(). That got rid of the never-ending messages. I'd still like to know what that happens...

I have other problems remaining, but I'm pretty sure they're unrelated.

Anyone else out there detest debugging other people's old ugly code?

J

Draw problem

6-Dec-01 3:45

Hi,

I have got a dialog(CDialog). In OnInitDialog() I create second dialog(CPropertyPage), which is child of first dialog. When I execute app, second dialog is redrawed only when I resizing the app window ?? Why ??

(routeing messages ?? )

Re: Draw problem

Michael P Butler6-Dec-01 3:57

Michael P Butler

6-Dec-01 3:57

Does the second dialog appear at all, or is this just a problem with the redraw. You'll have to post your code so we can see what is wrong.

Michael Smile | :)

Painting dialog background

6-Dec-01 4:12

Ufff

Its now ok,but :

Where must i write the code for painting dialog background ? When i put the code in OnPaint(), all control are redrawed by background.

Re: Painting dialog background

Christian Graus6-Dec-01 9:17

Christian Graus

6-Dec-01 9:17

OnEraseBkgnd.

Christian

After all, there's nothing wrong with an elite as long as I'm allowed to be part of it!! - Mike Burston Oct 23, 2001

Sonork ID 100.10002:MeanManOzI live in Bob's HungOut now

Re: Painting dialog background

Michael Dunn6-Dec-01 9:33

Michael Dunn

6-Dec-01 9:33

Wizard_01 wrote:
Where must i write the code for painting dialog background ?

Handle WM_ERASEBKGND and paint the background in that handler.

--Mike--
http://home.inreach.com/mdunn/
Help! Help! I'm being repressed!!
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your

with

and

Sonork - 100.10414 AcidHelm

Looking for panacea...Type of the control...I have only CWnd pointer

Ahmad996-Dec-01 3:07

Ahmad99

6-Dec-01 3:07

Suppose IDC_EDIT1 is the ID of the edit box, so if i do

if (GetDlgItem(IDC_EDIT1)->IsKindOf(RUNTIME_CLASS(CEdit)))
AfxMessageBox("Type of the class is CEdit");

Message should be displayed.but it is not displaying.

I want to check the type of control, and i have only CWnd pointer , what should i do.

EXPLANATION
............
I have a CWnd Pointer and from this pointer i want to check what was the type of the control,whether it is CEdit, or CButton etc.
what should i do

Re: Looking for panacea...Type of the control...I have only CWnd pointer

Rickard Andersson²⁰6-Dec-01 3:24

Rickard Andersson²⁰

6-Dec-01 3:24

The use of RUNTIME_CLASS may not return the right stuff for ya because you perhaps haven't declared DECLARE_DYNAMIC, DECLARE_DYNCREATE, or DECLARE_SERIAL in your class:

"RUNTIME_CLASS returns a pointer to a CRuntimeClass structure for the class specified by class_name. Only CObject-derived classes declared with DECLARE_DYNAMIC, DECLARE_DYNCREATE, or DECLARE_SERIAL will return pointers to a CRuntimeClass structure." <-- From MSDN Library

------------------------------
©0d3 ©®4©k3® - That's me! Smile | :)

------------------------------

Re: Looking for panacea...Type of the control...I have only CWnd pointer

Jon Hulatt6-Dec-01 6:06

Jon Hulatt

6-Dec-01 6:06

if (GetDlgItem(IDC_EDIT1)->IsKindOf(RUNTIME_CLASS(CEdit)))
        AfxMessageBox("Type of the class is CEdit");

...is never going to work because...

CWnd *p_MyWnd=GetDlgItem(IDC_EDIT1);
CRuntimeClass *p_RTC=p_MyWnd->GetRuntimeClass();

in the debugger shows p_RTC to be a kind of CTempWnd. Your class is of no particular type until your pointer is cast as the desired type. Basically, GetDlgItem(IDC_EDIT1) is NOT a CEdit, until you cast it as CEdit.

Of course, this doesn't help you much, but it might help you sleep at night Smile | :)

My tuppence aimed at actually solving your problem though:

work out the window class (not the same as a C++ class.

Sorry to dissapoint you all with my lack of a witty or poignant signature.

Re: Looking for panacea...Type of the control...I have only CWnd pointer

Alvaro Mendez6-Dec-01 10:13

Alvaro Mendez

6-Dec-01 10:13

I recommend you use the window's class name instead:

CString strClassName;
::GetClassName(GetDlgItem(IDC_EDIT1).GetSafeHwnd(), strClassName.GetBuffer(100), 100);
strClassName.ReleaseBuffer();
 
if (strClassName == "EDIT")
   AfxMessageBox("It's an edit box");

Take a look at CreateWindow for a list of possible class names.

Regards,
Alvaro

Re: Looking for panacea...Type of the control...I have only CWnd pointer

Jon Hulatt6-Dec-01 22:29

Jon Hulatt

6-Dec-01 22:29

Take a look at CreateWindow for a list of possible class names....

.... or play with Spy++. Spy++ really is great. Anyone want to form the Spy++ appreciation society with me?

Sorry to dissapoint you all with my lack of a witty or poignant signature.

Please Help !!!

The_Server6-Dec-01 1:26

The_Server

6-Dec-01 1:26

I have a BMP file- MyBmp.BMP.

How can I display it grayscaled ?

I'm will use MFC if I'll need but I must see it grayscale.

10x.

BTW: come to #CodeProject on DalNet (mIRC)

Re: Please Help !!!

Jon Hulatt6-Dec-01 2:28

Jon Hulatt

6-Dec-01 2:28

Use photoshop or paint shop pro to greyscale it first?

Sorry to dissapoint you all with my lack of a witty or poignant signature.

Re: Please Help !!!

Christian Graus6-Dec-01 9:19

Christian Graus

6-Dec-01 9:19

Were did my reply go ? Anyhow, I said that you can use Paintlib, or add a gray function to Chris's DIBSECTION wrapper. The latter is probably faster.

Christian

After all, there's nothing wrong with an elite as long as I'm allowed to be part of it!! - Mike Burston Oct 23, 2001

Sonork ID 100.10002:MeanManOzI live in Bob's HungOut now

Enum...

Bernhard6-Dec-01 1:10

Bernhard

6-Dec-01 1:10

i really like to know much bout things i use.. and today there are enums..
i've tried to find some informations in 3 sources (msdn, stroustrup the c++ programming language and thinking in c++).. and i couldn't really find an answer for my questions..

* what is the difference between named and unnamed enums

enum num1
{
    value1
};
enum
{
    value2
}

* do i HAVE to call them qualified ? (num1::value)
* what is the big advantage of using enums instead of #defines (outside of classes)
* "thinking in c++" said that you should use static const - var's instead of enums, is this really better ?

i hope somebody can help me to answer these questions..
thanks in advance

Bernhard

"There are three roads to ruin: women, gambling and technicians. The most pleasant is with women, the quickest is with gambling, but the surest is with technicians." Georges Pompidou

Re: Enum...

BlackSmith6-Dec-01 11:00

BlackSmith

6-Dec-01 11:00

The greatest atvantage about enum is that compiler (C++'s) does strong type
checking on'em.

take e.g.:

enum Days{SUNDAY, MONDAY,...};

void MyClass::CheckDay(Days day)
{
switch(day)
case SUNDAY : cout << "Sunday";
//.....
}

(We know that SUNDAY == 0)

MyClass dayChecker;
dayChecker.CheckDay(0); //Compiler error: The method expects to
// receive Days data type
dayChecker.CheckDay(SUNDAY); //This will.

--BlackSmith--

"With the help of all mighty", 2001, Me.

Thank you all for your great help

Bernhard6-Dec-01 19:20

Bernhard

6-Dec-01 19:20

<eom>

"There are three roads to ruin: women, gambling and technicians. The most pleasant is with women, the quickest is with gambling, but the surest is with technicians." Georges Pompidou

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