mfc >> Three MFC Questions

by Joseph M. Newcomer » Sun, 25 Apr 2004 23:17:41 GMT

See below...
On Sun, 25 Apr 2004 10:00:39 -0500, "Todd L. Peters" < XXXX@XXXXX.COM >
wrote:

>I am new to MFC and have three questions.
>
>1. I would like to write a dialog box that allows users to choose the color
>for various entities in the program, say apples and oranges. Next to
>"Apples", the user can press a button, and the standard MFC Dialog for color
>picking comes up. This much is not a problem. However, how can I, after
>(and before) the color is picked, color the face of the button with the
>currently selected color?
*****
Use an owner-draw button, and in the OnDrawItem, draw the background using PatBlt or
FillSolidRect.
*****
>The only way I know of is by displaying bitmaps,
>and it certainly seems impractical to have 256 (or more) bitmaps to display
>each and every possible color pick. Perhaps there is a way to color the
>face of the button with a color code?
****
No bitmaps required. Besides, you'd need 16MB of bitmap, but if you used bitmaps, you
would want to create it on-the-fly. But as I point out, it isn't necessary.

You can get an example of an owner-draw button by taking a look at my Better Bitmap Button
on my MVP Tips site. Throw away the code that works with the bitmap, and just retain the
core structure.
*****
>
>2. I have been writing Dialog Boxes that dynamically configure and resize
>based on user selections within the dialog box. I have been using
>this->setWindowPos within the dialog box class to resize the window.
>However, is there a way to ensure that my "Accept" and "Cancel" buttons stay
>docked at the bottom of the dialog box, or do I have to move them as well?
>How do I move them?
****
SetWindowPos, same as all your other buttons. There is no concept of "docking" at runtime.
****
>
>3. How do I control the size and position of the application when it starts
>up? Do I do this by calling setWindowPos in the OnInit or Create functions
>for my MainFrm and ChildFrm classes, or is there another way?
****
SetWindowPos your dialog in OnInitDialog. In a dialog-based (as opposed to
CFormView-based) app, there is no MainFrm.cpp or ChildFrm.cpp.

In a CFormView-based app, you would do this, as you point out, in your CMainFrame class,
probably in the OnCreate.
*****
>
>Thank you,
>Todd L. Peters
>

Joseph M. Newcomer [MVP]
email: XXXX@XXXXX.COM
Web: http://www.flounder.com
MVP Tips: http://www.flounder.com/mvp_tips.htm

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The output of the compiled code with g++ on debian etch is:

Default constructor of Exmpl **
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Copy constructor is called
Copy constructor is called **
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0
4.5
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4.5
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Destructor for class is used
Destructor for class is used
Destructor for class is used
Destructor for class is used
Destructor for class is used
Destructor for class is used
Destructor for class is used
Destructor for class is used
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