Re: How to do a SetPixel with GDI+ - C / C++ / MFC Discussion Boards

Brian van der Beek20-Feb-02 8:48

20-Feb-02 8:48

Thanks for your reply but I already found the answer. Instead of using DialogBox to create the dialog I should use DialogBoxParam. This allows you to pass the this pointer of the class in the lparam of the WM_INITDIALOG message. Problem solved.

Re: DialogProc

Paul M Watt20-Feb-02 9:17

Paul M Watt

20-Feb-02 9:17

Store a pointer to your dialog class in the window data field of the actual dialog window.
Use the SetWindowLong function and set the GWL_USERDATA field.

Then in your static member function of the dialog class that you are using as your dialog proc function, call:

<br />
CYourDialog *pDlg = dynamic_cast<CYourDialog*>(GetWindowLong(hWnd, GWL_USERDATA));<br />
if (!pDlg)<br />
{<br />
    // this message is not for you.<br />
}<br />
<br />
    //Otherwise handle all of your code here.<br />
<br />

This trick will also work for regular windows. If you already have data stored in the USERDATA field, then you can simply convert this data to a structure and include the pointer to your object, or move the data into your class and still hold the this pointer in the USERDATA field.

Button Menu

Anthony988720-Feb-02 7:12

Anthony9887

20-Feb-02 7:12

I'm trying to add a drop down menu to a button using Windows SDK not MFC.

Thanks

Re: Button Menu

Joaquín M López Muñoz20-Feb-02 7:19

Joaquín M López Muñoz

20-Feb-02 7:19

I guess

<a href="http://msdn.microsoft.com/library/default.asp?url=/library/en-us/shellcc/platform/CommCtls/winui/menus_0hdi.asp">TrackPopupMenu</a>

is the place to start from.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Re: Button Menu

Ravi Bhavnani20-Feb-02 7:23

Ravi Bhavnani

20-Feb-02 7:23

You need to create and track a popup menu in response to the button click. See CreatePopupMenu() and TrackPopupMenu.

/ravi

"There is always one more bug..."
http://www.ravib.com
ravib@ravib.com

How to do a SetPixel with GDI+

20-Feb-02 7:04

Hi,

I'm migrating from GDI to GDI+ under Visual C++ 6.0.
I was calling SetPixelV on a device context. Now with a HDC and a graphics object, how to do a SetPixel ?

Thanks for your help

Nicolas

Re: How to do a SetPixel with GDI+

Mazdak20-Feb-02 7:30

Mazdak

20-Feb-02 7:30

I don't know the answer,but Christian Graus has some articles about GDI+,put message there ,maybe he knows it.Check this

Mazy

"So,so you think you can tell,
Heaven from Hell,
Blue skies from pain,...
How I wish,how I wish you were here."
Wish You Were Here-Pink Floyd-1975

Re: How to do a SetPixel with GDI+

Jon Gohr20-Feb-02 9:15

Jon Gohr

20-Feb-02 9:15

Check out the SetPixel method the System.Drawing.Bitmap class? Wink | ;)

Re: How to do a SetPixel with GDI+

20-Feb-02 11:53

I know this method exists but how to get a Bitmap reference of an existing DC with already drawn things in it ?

How to Hide Dialog window in a thread

sanskypotov20-Feb-02 6:30

sanskypotov

20-Feb-02 6:30

In an EXE I have a Dialog and I have another Dialog
which is started with DoModal()
in another thread using AfxBeginThread.
I want to hide this second Dialog

I have already tried to
ShowWindow( SW_HIDE );
MoveWindow( 0 , 0 , 0 , 0 , false );

But I still see the window on the taskbar.
Can anyone offer any solution.
Thanks,
Sansky
Big Grin | :-D

Re: How to Hide Dialog window in a thread

Joaquín M López Muñoz20-Feb-02 6:50

Joaquín M López Muñoz

20-Feb-02 6:50

Cannot test this now, but I think that having the first dialog as the parent of the second one will prevent the latter from appearing on the taskbar.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Dialog Bars?

20-Feb-02 6:19

Hi There,

I've gota project where I'll be using some dialog bars. I need to implement a tree control on the left side of the main frame that navigates between different screens, kind of like visual studio. I've embedded a CDialogBar member in the CMainFrame class, called create on it. I've got a dialog template where I'll stick a tree control, I guess.

At any rate, I imagine I'm not the first person to try this. Any tips? Any sample code you could recommend?

Thanks,

Aaron

Re: Dialog Bars?

yellowine20-Feb-02 8:12

yellowine

20-Feb-02 8:12

There are several examples which fit what you have described, take a look at the article below:

CSizingControlBar - a resizable control bar

Hope this is what you need.

Quick Queustion

Steve Thresher20-Feb-02 6:13

Steve Thresher

20-Feb-02 6:13

Is it possible to use the Win32 API to setup user groups on Windows NT/2000/XP? If it is could someone please point me at the appropriate API calls.

Thanks for any help you can provide.

Systems AXIS Ltd - Software for Business ...

Re: Quick Queustion

Joaquín M López Muñoz20-Feb-02 7:03

Joaquín M López Muñoz

20-Feb-02 7:03

Check Microsoft Network Management API.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Rendering Points and Lines in DirectX

20-Feb-02 6:18

I have a small problem rendering lines in DirectX (Version 8) with DrawPrimitive, except, that there seems to be no way to set the width of the line. The same applies to points.

Does anybody know a solution!?

Thanks in advance.

Klaus

Reading lines in CAsyncSocket

Jon Hulatt20-Feb-02 5:57

Jon Hulatt

20-Feb-02 5:57

Hi,

I've got a CAsyncSocket derived class, trying to implement my own high level protocol.

My command structure consists of a variable length line of text. The kind of thing that a CStdioFile::Readline() likes.

I have an OnReceive() handler which successfully reads the data. To break it into lines, i'm appending my data to a buffer as i receive it, then searching the buffer for \r\n. then, chopping out the left most part of the buffer based on the offset i found the \r\n.

It's all a bit slow though. I'm pretty sure that wanting data line by line is a pretty common need when using CAsyncSocket. How do other people implement this, efficiently?

Jon

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

Re: Reading lines in CAsyncSocket

Joaquín M López Muñoz20-Feb-02 6:41

Joaquín M López Muñoz

20-Feb-02 6:41

Your method is essentially the only way to go. Winsock has no built-in support for breaking input into lines. So, if your app is lacking for speed, your only solution is trying to implement this search and cut algorithm more efficiently.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Re: Reading lines in CAsyncSocket

Tim Deveaux20-Feb-02 7:00

Tim Deveaux

20-Feb-02 7:00

Just wondering if you have the option of just sending one line at a time.

Some command protocols are blessed with this type of exchange because there's nothing to do till the 1st one line finishes and data is returned to the client, others might use an app level ACK/NACK scheme - either way, each command is atomic.

Re: Reading lines in CAsyncSocket

Joaquín M López Muñoz20-Feb-02 7:14

Joaquín M López Muñoz

20-Feb-02 7:14

Just wondering if you have the option of just sending one line at a time.

In general, no you can't. For connection-oriented sockets (TCP/IP), there's no guarantee at all as to how data chunks are to be received on the other end of the connection. In some cases, data chunks will be coalesced, in others they will be chopped. As a general rule, it is very bad design to assume that "boundary integrity" is preserved in any manner. Having this integrity for a particular network does not mean it'll be kept on another configuration (e.g. with different subnetworks) or even when the conditions on the network change (e.g. high traffic).
For connectionless sockets, aka datagrams (UDP), chunk integrity is preserved. But one has to be careful to not assume some fixed maximum datagram size (it can vary for different stacks and scenarios).

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Re: Reading lines in CAsyncSocket

Tim Deveaux20-Feb-02 7:22

Tim Deveaux

20-Feb-02 7:22

Yes, fine, but if the client sends a line and waits for ack from the server before sending another...

Re: Reading lines in CAsyncSocket

Joaquín M López Muñoz20-Feb-02 7:44

Joaquín M López Muñoz

20-Feb-02 7:44

Yes, that'd work. Another solution for preserving chunk boundaries is sending first the length of each chunk. This way the receiver always knows how many bytes to gather for each block. This solution can be mounted as a microprotocol on top of TCP/IP and hidden to the user by some CSocket-like class.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Re: Reading lines in CAsyncSocket

Dharminder20-Feb-02 20:15

Dharminder

20-Feb-02 20:15

There is a slightly more efficient approach that you can use, but only if you have control over how the client program generates the message.

What I tend to do is preceed each message with a header. In my particular case, I've been using long integers, in network byte format to be compatible with all types of machines, to indicate the length of the following data.

In my case my program reads the 4 bytes and knows immediately how long the subsequent data is and accordingly waits for the buffer to fill up sufficiently. This saves significant processing as there is no scan necessary to find the end of the message.

However, as I said, all this depends upon whether or not you have control over the client program. If you can modify it to provide the message in this way then it can work. Otherwise your approach is essentially the only one that can be taken.

Good Luck!

Dharminder S. Birdi

Debugging MFC app in VS .Net?

Stan Shannon20-Feb-02 5:19

Stan Shannon

20-Feb-02 5:19

Is anyone having problems trying to debug a MFC app in the new VS .Net? I can create a brand new MFC app under .Net, add nothing to it, compile it, then select "start" and the entire application (.Net) hangs. I have to restart it. The application I'm trying to run does seem to start but it never becomes accessible.

It runs fine if I select the "start without debugging" option.

Confused | :confused:

"Thank you, thank you very much" Elvis.

Re: Debugging MFC app in VS .Net?

Mazdak20-Feb-02 5:31

Mazdak

20-Feb-02 5:31

I have no problem with it.
Check your debug configuration:Tools-->options
and also your project setting.

Change some of them and see what happend,also if you use win2000 or xp,maybe you login
with username that doesn't have debugging permission.

After all of them,maybe you need to reinstall VS.NET again Smile | :)

Mazy

"So,so you think you can tell,
Heaven from Hell,
Blue skies from pain,...
How I wish,how I wish you were here."
Wish You Were Here-Pink Floyd-1975

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.