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Hi,
I'm in the process of writing a button control that has "dead man" behaviour. The button will be used to control some machinery, and the customer has asked for this button control that will only allow activity to happen while the mouse button is pressed on it.
I'm making a control that intercepts messages WM_LBUTTONDOWN and WM_LBUTTONUP so that it can notify the backend when the user presses/releases the button. My question is this: Is there is any chance (even the slightest most skinny chance) that delivery of the WM_LBUTTONUP message might fail? I'd imagine that there might be a 1 in a million chance. So does anyone have any advice for implementing this safely?
Joel Holdsworth
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Try pressing the mouse button over the control, moving the mouse away and then releasing the button.
I think this can cause problems but I think you might have to put it over a larger conrol and catch the mouse movements on the larger control, thus the larger control acts as a 'guard rail'.
It's many years since I saw this issue so can't give more info off hand.
Elaine ![Rose | [Rose]](https://codeproject.freetls.fastly.net/script/Forums/Images/rose.gif)
The tigress is here 
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Even having a "guard rail" larger control might not work if the user moves the mouse entirely outside of the application window and then releases the button. The best way to deal with that is to use the SetCapture() function so that the necessary window receives mouse events even if they occur outside the window.
Sincerely,
Alexander Wiseman
Est melior esse quam videri
It is better to be than to seem
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A better way to set up the "Guard Rail" would be to restrict the mouse cursor using the ClipCursor function. See ClipCursor and GetClipCursor in MSDN.
"You're obviously a superstar." - Christian Graus about me - 12 Feb '03
"Obviously ??? You're definitely a superstar!!!" mYkel - 21 Jun '04
Within you lies the power for good - Use it!
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Good point. ClipCursor will prevent the mouse from even going outside the boundary. For allowing the user to bring the mouse outside the boundary and still handling messages you would use SetCapture.
Thanks for the tip.
Sincerely,
Alexander Wiseman
Est melior esse quam videri
It is better to be than to seem
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Joel Holdsworth wrote:
Is there is any chance (even the slightest most skinny chance) that delivery of the WM_LBUTTONUP message might fail?
It depends what you mean by "fail". The message will be sent (barring a malfunction in Windows), but the time between the user clicking the button and the delivery of the message could be significant. See this[^] article for an alternative way to implement the dead man's feature.
/ravi
My new year's resolution: 2048 x 1536
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ravib@ravib.com
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I understand that Microsoft are now giving their Visual C++ Toolkit away for free. 
Some websites claim that the compiler is equivalent to the Standard C++ compiler (i.e. not optimizing). On the other hand, Microsoft claim the compiler is the same as their Professional compiler. This seems too good to be true! 
Surely one of the main incentives for purchasing .NET Professional is that you get an optimizing compiler? 
In other words, what's to stop me just buying C++ .NET Standard (which comes pretty cheap) and, when I've finished developing my app, using the free toolkit to build the final, optimized, distributable exe?
In a nutshell: what's the catch? 
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As I understand it, it is the full optimizing compiler.
LiquidEyes wrote:
Surely one of the main incentives for purchasing .NET Professional is that you get an optimizing compiler?
Well, you also get the other three languages if that's of any use to you.
LiquidEyes wrote:
In other words, what's to stop me just buying C++ .NET Standard (which comes pretty cheap) and, when I've finished developing my app, using the free toolkit to build the final, optimized, distributable exe?
As far as I can see - nothing.
Kevin
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Kewl. Thanks for the info.
Given that I'm not interested in the other languages, is there anything else about .NET Professional I should be particularly interested in?
MS seem to imply that it has superior debugging facilities compared with the Standard edition, but if we're just talking fancy-pants stuff like remote debugging and such-like, then I'm not too fussed.
I just want to write Visual C++ apps on my home PC (ultimately, with a view to distributing my apps). I use .NET Pro at work, so I'm wondering whether, when I buy C++ .NET Standard for home use, I'm suddenly going to realise there are a load of missing features that I badly want! 
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You can also copy and replace the standard edition's compiler/linker files for the toolkit's compiler/linker files. It has been working for me without problems.
Happy Programming and may God Bless!
"Your coding practices might be buggy, but your code is always right."
Internet::WWW::CodeProject::bneacetp
N-Tech Productions
http://www.n-tp.com/
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But can you set the compiler's "Optimize" switches? The Standard IDE won't let you select any optimization, and I wonder if it removes any that you manually add...
Any experience with optimized output from Standard Edition with replaced compiler/linker files?
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Unfortunately, it appears that the optimization switches are still disabled with or without the compiler files in place.
I don't really have any experience with optimized output in the Standard Edition. After looking through one of my Visual C++.NET project files, it looks like Optimization through the Standard IDE is a no-show. Sorry to deliver the bad news.
Happy Programming and may God Bless!
"Your coding practices might be buggy, but your code is always right."
Internet::WWW::CodeProject::bneacetp
N-Tech Productions
http://www.n-tp.com/
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hi,
I have a "first.dll" ..Now I want to generate C++ code from that DLL.Can I do that?.if possible, pleae send me reply where I can find that..
Thanks.....
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pubba wrote:
Now I want to generate C++ code from that DLL.Can I do that?.
No.
"When I was born I was so surprised that I didn't talk for a year and a half." - Gracie Allen
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I thought you could back-engineer programs? (mostly not legal)
I wouldn't know how or what though.
Maybe you know what backwards engineering is, because I thought it was creating code from dll's/exe's...?
(and we're learning every day  )
tnx.
"If I don't see you in this world, I'll see you in the next one... and don't be late." ~ Jimi Hendrix
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V. wrote:
I thought you could back-engineer programs?
Reverse-engineering is possible, but you cannot get C++ code from an EXE or DLL. The best you could hope for is barely-legible assembly.
"When I was born I was so surprised that I didn't talk for a year and a half." - Gracie Allen
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There are products that can generate high level code from machine code.
Tim Smith
I'm going to patent thought. I have yet to see any prior art.
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Do tell.
"When I was born I was so surprised that I didn't talk for a year and a half." - Gracie Allen
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Aside from the site containing lots of broken links, some of which take you to adult-related sites, I saw nothing about producing high-level code as a result of reverse-engineering an EXE or DLL. This might have been a better choice.
"When I was born I was so surprised that I didn't talk for a year and a half." - Gracie Allen
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Right, ny intention was to provide a starting point for reverse engineering, and since i've seen Mammon's capable contribution to rev eng, it would be a good place to start learning about it.
Wasnt intending to supply a "decompile to C source code" site.
Bikram Singh
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Hello,
This is the second (and last) time I (try) to approach this issue -- I'm posting a second time because I don't quite understand ScrollDC's mechanics, so please forgive for the (almost) duplicated post.
Righ then, I have this (custom) control which outputs text within a RECT viewport and, at some point in time, there is the need to scroll its contents (either down or up -- always vertically though).
The problem I keep getting is that whenever a window hovers the control, the DC does not scroll the contents properly. Lets imagine the following situation:
My custom control's pos/size: [0,0] - [100, 200] // [x0,y0] - [width,height]
Now imagine a window, say a dialog box, hovering at [75, 60] - [500, 350]
My custom control's DC does not scroll from [75,0] - [100,60] , I keep getting "garbage" on that location
I know I'm doing something wrong here, but I just don't know what.
This is the call I'm doing to the ScrollDC:
DCHandle -> ScrollDC(0, iYScroll, &ViewArea, &ViewArea, NULL, NULL);
iYScroll represents the amount of pixels to scroll up/down
ViewArea is basically the viewport area
Any comments and/or suggestions are welcome.
Thank you for taking the time,
David
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Would you be willing to send me your code so I can look at it? I don't really have time to pull together something which has this scenario and I don't think I can answer your question off the top of my head.
Of course, MSDN doesn't say anything about this situation in ScrollDC, but I did find this comment:
[MSDN]
An application should use the ScrollWindow member function of class CWnd when it is necessary to scroll the entire client area of a window. Otherwise, it should use ScrollDC.
[/MSDN]
ScrollWindow's description in MSDN: "CWnd::ScrollWindow: Scrolls the contents of the client area of the current CWnd object."
ScrollDC's description in MSDN: "CDC::ScrollDC: Scrolls a rectangle of bits horizontally and vertically."
It may be that ScrollDC simply isn't suited for what you are doing, since you probably want the whole client area of your custom control to be scrolled. I'm not sure if using the other function will solve the problem. Give it a try and if it doesn't work I would be willing to look through your code if you would be willing to send it (Alexander@wisemanweb.com).
Sincerely,
Alexander Wiseman
Est melior esse quam videri
It is better to be than to seem
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To Hello,
Created dynamically an 2-D array CButtons in the CFormView.
How do you add the message handler?
Thanks.
S1189216G
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Use this macro to map a contiguous range of control IDs to a single message handler function for a specified Windows notification message, such as BN_CLICKED.
ON_CONTROL_RANGE(wNotifyCode, id1, id2, memberFxn )
From the MSDN library
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