C / C++ / MFC

CEvent Syncronization Class!

12-Mar-02 19:36

Line for line I can't help you, but there are examples of what I think you are looking for here at CP, the greatest place on earth (virtual anyways).

Do a search for IE Toolbar.

Cheers!

"An expert is someone who has made all the mistakes in his or her field" - Niels Bohr

MarkPQ12-Mar-02 13:58

MarkPQ

12-Mar-02 13:58

I am making a multithreaded app that connects to a serial port and already lots of people here have been a great help!

At the moment I have several threads, two in particular (which coincidentally I have put in a seperate dll) are called RxThread and TxThread, obviously controlling the transmission and receiving of data from the serial port.

What I am trying to do is have a CEvent that I can signal with the RxThread when I have received a reply from a message sent using TxThread (to serial). I know in TxThread I want to WaitForSingleObject for a little while, and if timedout check for messages to TxThread (ie WM_QUIT, not serial messages) and Retry sending (to Serial)!

The trouble is I'm not sure how to create the CEvent object so that I can set it with the RxThread each time I get a reply, and wait for it in TxThread so I can block the thread for a little while!

Thanks for any help
-Mark

Re: CEvent Syncronization Class!

Serge Krynine12-Mar-02 14:16

Serge Krynine

12-Mar-02 14:16

Option 1. The RxThread and TxThread belongs to the same process:
- create unnamed CEvent object;
- create RxThread object and pass the reference to the unnamed CEvent object;
- create TxThread object and pass the reference to the unnamed CEvent object;

Option 2: The RxThread and TxThread belongs to different processes:
Both threads must create named CEvent class object with the same name.

Creating Styles...

CDuddley12-Mar-02 13:49

CDuddley

12-Mar-02 13:49

How would you create and implement styles into your own custom class? Thanks for you replies in advance.

-CDuddley

Maximilien12-Mar-02 15:20

Maximilien

12-Mar-02 15:20

CDuddley wrote:
styles

Styles ???

Max.

alex.barylski12-Mar-02 15:49

12-Mar-02 15:49

I'll assume you mean styles like WS_VSCROLL and such...?

Umm...well I dunno if windows reserves all 32 bits of the DWORD nStyle paramter, but you could find out pretty easy and use bit locations that weren't used or use a DOWRD StyleEx and set your own bits using bitwise OR's.

Like this overloaded version of Create

Create(CWnd* pParent, DWORD nStyle)
{
  //Extract the bits your interested in using bitwise AND's
  //(i think) and basically do what you want to/with them before 
  //sending the rest to default Create.
  CWnd::Create(nSytle...blah);
}

For instance if bit 17 wasn't already used by CreateWindow() you could use it to specifiy SHOW/HIDE 3D borders around custom button control.

Cheers!

"An expert is someone who has made all the mistakes in his or her field" - Niels Bohr

CDuddley12-Mar-02 16:27

CDuddley

12-Mar-02 16:27

How do you handle them I guess is what I was wondering. Say you have an enumeration.

enum { ID_STYLE1 = 0, ID_STYLE2 = 1, ID_STYLE3 = 2 };
How do you handle the those styles in a function with the bitwize OR and AND ops? Thanks for the inputs in advance.

-CDuddley

Serge Krynine12-Mar-02 17:02

Serge Krynine

12-Mar-02 17:02

Hope this is what you are after.
Serge

class MyClass

{

public:

enum Style

{

Style1 = 1 << 0, // bit 0

Style2 = 1 << 1, // bit 1

Style3 = 1 << 2, // bit 2

// so on

};

MyClass() : m_styles(0) {}

void SetStyle(Style style) {m_styles |= style;}

void ClearStyle(Style style) {m_styles &= ~style;}

void Dump() {printf("Style = 0x%08X\n", m_styles);}

private:

unsigned int m_styles;

};

void main()

{

MyClass mc;

mc.SetStyle(MyClass::Style1);

mc.Dump();

mc.SetStyle(MyClass::Style2);

mc.Dump();

mc.SetStyle(MyClass::Style3);

mc.Dump();

mc.ClearStyle(MyClass::Style3);

mc.Dump();

mc.ClearStyle(MyClass::Style2);

mc.Dump();

mc.ClearStyle(MyClass::Style1);

mc.Dump();

}

alex.barylski12-Mar-02 19:29

12-Mar-02 19:29

#define CWS_3DBORDER  0x01  //First bit of DWORD style is now used by child window style (CWS)

//Create custom control window with custom style
m_wndChild.Create(this, WS_CHILD | WS_VISIBLE | CWS_3DBORDER);

//Custom control overloaded Create function
CCustom::Create(CWnd* pParent, DWORD nStyle)
{
  m_b3DBorder = nStyle & MASK;
}

//CCustom control OnPaint handler
CCustom::OnPaint()
{
  CPaintDC dc(this);
  if(m_b3DBorder)
    //Draw 3d border cuz it was specified in style flag

  //Continue with normal drawing code
}

You may have to give the and operation the once over
I dunno how accurate my attempt at masking bits is in the above...but you should figure it out easily. I did try and give a solid example of how I would use custom flags.

Cheers!

"An expert is someone who has made all the mistakes in his or her field" - Niels Bohr

CPP question

alex.barylski12-Mar-02 13:01

12-Mar-02 13:01

I have created a control from scratch derived from CWnd.
The only problem I had was deriving from this control at first I couldn't figure out why nothing was happening after the overloadded Create function was called. I quickly figured out how t fix it, but i'm not 110% sure why?

Basically in my newly derived class I had to implement(???) each function that was implemented in the base class and call the base class version in the derived class.

Is there another way around this...?

Cheers!

"An expert is someone who has made all the mistakes in his or her field" - Niels Bohr

Rick York12-Mar-02 14:59

Rick York

12-Mar-02 14:59

I would be puzzled too because, generally speaking, you do not have to do this. You only need to implement functions that are overridden in derived classes or those that are pure virtual (not implemented in the base class.)

Something strange is afoot at the Circle-K.

alex.barylski12-Mar-02 15:37

12-Mar-02 15:37

I can't figure it out...i've done nothing out of the ordinary...my computer is definetly screwing up though.

default paramters in one of my member functions compiled fine, but the classwizrd wouldn't locate the function...so I had to remove one default parameter and everything worked fine again.

Thanx

"An expert is someone who has made all the mistakes in his or her field" - Niels Bohr

Jon Hulatt12-Mar-02 22:25

Jon Hulatt

12-Mar-02 22:25

Did you really have to implement every function? CWnd has an awful lot of functions.

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