C / C++ / MFC

14-Jun-07 4:19

In my application I have a button to start another application (a different program altogether). I use the old WinExec which works fine. The problem is that I don't want multiple instances of the other application. (For example the user clicks on the first application and again it gets control and then he clicks on the button again.)

What I would like to do is transfer control to that program if it is running and not start and new instance of it. (This would be the equivalent of clicking on its icon on the bar on the bottom of the screen.) Is there a way to do such a thing?

Thanks,
Ilan

led mike14-Jun-07 4:26

led mike

14-Jun-07 4:26

IlanTal wrote:
Is there a way to do such a thing?

There are many ways. See Inter-process communication[^]

IlanTal14-Jun-07 8:10

14-Jun-07 8:10

I don't want to send any information between the programs, just give the second program control - like you do when you click on the task bar.

David Crow14-Jun-07 4:46

14-Jun-07 4:46

If you have access to the other application's source code, see here.

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

IlanTal14-Jun-07 8:13

14-Jun-07 8:13

Today in the second program I use a mutex to detect the second instance and kill it.
The reply below this one is correct in the sense that I want to give it focus.
However I don't know what it means to give focus to a totally different process.

David Crow14-Jun-07 8:41

14-Jun-07 8:41

IlanTal wrote:
However I don't know what it means to give focus to a totally different process.

The one and only instance of your "second program" does this with a call to SetForegroundWindow().

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

IlanTal14-Jun-07 23:47

14-Jun-07 23:47

Thank you very much. That is my missing link.

DjinnKahn14-Jun-07 5:03

DjinnKahn

14-Jun-07 5:03

maybe:

Use ::FindWindow() to check if the other program is running, and get the window handle if it is.

Use something like ::SetFocus() or ::SetForegroundWindow() to give the other program control (now that you have its window handle).

David Crow14-Jun-07 5:39

14-Jun-07 5:39

DjinnKahn wrote:
Use ::FindWindow()...

...to cause a potential deadlock situation.

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

IlanTal14-Jun-07 8:15

Creating array/object at runtime.

14-Jun-07 8:15

So I don't use FindWindow(). If I would use something better, how could I give focus?

Sameer_Thakur14-Jun-07 4:07

Sameer_Thakur

14-Jun-07 4:07

Hi.

I want to know how I can create an array/object at runtime if I don’t know about its data type.
For example,
I have an array Say Arr, but I don’t have any information about the data type of elements it stores. It might be an array of int, float, char or even user defined data type (user defined class).
I can get the information about its class or data type by using ‘type_info’, but how can I create an array/object of same data type at runtime?
Like if I want to copy the contents of an array Arr into another array say ‘NewArr’; of the same type at runtime, how can I create that second array NewArr, i.e. what should I specify as a data type of ‘NewArr’?

Thanks
Sameer Thakur

Re: Creating array/object at runtime.

David Crow14-Jun-07 4:47

Re: Creating array/object at runtime.

14-Jun-07 4:47

Sounds like a job for a template.

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

Mark Salsbery14-Jun-07 7:28

Mark Salsbery

14-Jun-07 7:28

Sameer_Thakur wrote:
how can I create an array/object of same data type at runtime?

AFAIK, there's no way to do this directly in C++.

You can, however, design a system of classes that are capable of creating/cloning themselves at
runtime and/or being created by type.

For an example implementation, check out the source code for MFC's CRuntimeClass and CObject
classes and the DECLARE_DYNAMIC/IMPLEMENT_DYNAMIC macros. This implementation has a common
base class which includes methods for runtime object creation based on a class name.
Because C++ has no built-in way to do this, the CRuntimeClass implements a list that maps
class names to creator functions.

Depending on the source of your source arrays, serialization may be useful as well.

Regardless, at the heart of these solutions is code that creates objects of a specific class,
which is all that C++ allows.

Just my 2-cents,
Mark

"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder

window caption

Neeraj Sinha14-Jun-07 3:56

Neeraj Sinha

14-Jun-07 3:56

I am trying to create a custom window caption for SDI application.I have
taken help from http://www.codeproject.com/gdi/customcaption.asp
The project on the above link use WM_NCPAINT,WM_NCACTIVATE and WM_SETTEXT handlers in the window procedure to draw and paint the caption bar.In this
project whole caption bar has been customized.

In my application,I don't want to draw and paint minimize,maximize and close buttons and let them be like the system's created default buttons.Actually these default buttons are getting drawn and painted but are not visible when the mainframe window gets activated.When I move the mouse on that region, then only those buttons are visible and work fine on clicking them.So, Can you please suggest me why those buttons may not be getting visible when the mainframe window gets activated?

With Regards

Neeraj Sinha

Re: window caption

Nelek14-Jun-07 19:46

Nelek

14-Jun-07 19:46

Have you checked out if button->ShowWindow (TRUE) works?

It would help if you post a bit of your code.

Greetings.

--------
M.D.V.

If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?

Getting Office language settings in MFC

Tarek Jabri14-Jun-07 3:23

Tarek Jabri

14-Jun-07 3:23

Hi everyone
i am developing a com add-in for MSWord in MFC, and i need to get the current UI language of the MSWord to make it the UI language of the add-in

i know that there is a method in the application class called get_LangaugeSetting , but in MFC this will retrun a dispatch, i need the LanguageSettings class to attach it with the dispatch
and i dont know where to get this class from

any help please
thanks all

Printing html displayed in WebBrowser2

SgLife14-Jun-07 2:21

SgLife

14-Jun-07 2:21

I am creating a dialog based application with a CWebBrowser2 control. I need to print the page displayed in the browser in landscape or portrait format without displaying the PrintDialog. Landscape or Portrait is decided by some other inputs.

I have two methods in my App class for setting the orientation and for starting the printing. Now the probelm for me is how to get the content in the browser or in other words how to get the html displayed in the browser? what to do after a m_Browser.GetDocument() call ?? I dont know how I can associate the html with DOCINFO structure ( setting the file name does not work of course). Landscape/Portrait modes and a dc.TextOut() for a hardcoded string works fine. But how to print the html displayed in the browser?

Please note: setting the orientation and using the ExecWb() function does not work because I am always getting portrait mode only.

Excpecting your valuable comments. Thanks.

Re: Printing html displayed in WebBrowser2

SgLife14-Jun-07 14:42

SgLife

14-Jun-07 14:42

Guys....any tips regarding this ?? Setting printing orientation, getting the content from a Webbrowser control and printing it. I dont want the print dialog to appear and the ExecWb() method always prints in portrait.

C++ Exception

T.RATHA KRISHNAN14-Jun-07 2:19

T.RATHA KRISHNAN

14-Jun-07 2:19

Hi ! I?'ve an application developed using MFC. When I run the project, a window will open. If I close the window manually (i.e by clicking the cross mark at the top left corner of the window), then an exception occurs.

It states:
Unhandled exception at 0x7c918fea in Perspective.exe: 0xC0000005: Access violation writing location 0x00000010.

If I break this exception,
Program control goes to a file called free.c

How do I resolve this Exception?

SandipG 14-Jun-07 2:25

SandipG

14-Jun-07 2:25

Check call stack you will be deleting some memory which is already freed or not allocated. May be Pointer will have some gabage value which you are trying to free.

prasad_som14-Jun-07 2:51

prasad_som

14-Jun-07 2:51

As sugeested earlier, it may be due to incorrect handling of memory, or writting out of bounds.
Run app in debug mode. See if call stack helps you.

Prasad
MS MVP - VC++

T.RATHA KRISHNAN14-Jun-07 2:54

T.RATHA KRISHNAN

14-Jun-07 2:54

How to view the call Stack? There is no tool bar icon for Call Stack in the VC++ Editor.