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Visual Studio67
From what I understand, when I create a dialog in the editor it is created

for a 96 DPI screen.



How do I deal with different DPI's? When I take my dialog app to a

different screen ( at a different DPI ) everything moves around.



I am trying to have my controls line up on a background image, so placement

is important.



TIA


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Read these articles. I am not an expert in DPI aware programing, but I have

used the info in these articles with my Windows XP apps and they work.



msdn2.microsoft.com/en-us/library/ms838191.aspx">msdn2.microsoft.com/en-us/library/ms838191.aspx

msdn2.microsoft.com/en-us/library/ms969894.aspx">msdn2.microsoft.com/en-us/library/ms969894.aspx



AliR.



"Golum256" <Golum256@discussions.microsoft.com>wrote in message



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Generally, this is a fundamentally losing idea. Dialogs are dynamically resized based on

a HUGE number of parameters OTHER than dpi (display size, display driver behavior, default

user font, phase of the moon, angular separation of Mars and Jupiter, who knows?) so the

basic premise is that you have NO control over what is happening.



There is no guaranteed correct solution, because the windows resize as appropriate.

Frankly, I had one of these programs cross my desk about ten years ago, and the first

thing I did was convince the client that the whole idea was fundamentally unsound. We

simply removed the fancy bitmap from the background.



However, there are some alternatives, but none of them are pleasant. You will have to

deal with the fact that ifyou create a bitmap of fixed size, it won't localize very well

(the controls may need more space in German, or Finnish, for example), it won't work if

the user is (like me) visually impaired (it's called "being over 45") and has selected a

default font larger than the normal linstalled font. So you would need a bitmap that had

a layout suitable for every possible combination of driver, screen size, resolution, and

default font selection (and I haven't even gotten into the issues of high-contrast support

for people who are seriously visually handicapped, or who need to use really large fonts).



But we had one situation where we were putting maps up on the screen. What we did with

those maps is do edge detection of areas of the map, and resize the controls to fit into

those areas. However, this worked because the areas were ALWAYS substantially larger than

the captions that were associated with them. We got away with it because we had a

different problem to solve.



If you assume localized bitmaps, and just make active areas on the bitmap, then it is

easier than placing controls. For exmple, for a pushbutton I was able to fit the

pushbutton into the region in question, but I created an owner-draw pushbutton with and

empty DrawItem handler, so what I ended up with was a reactive section of the bitmap. So

you have to fit the controls to the bitmap, and this has to be done by parsing the bitmap.

I know of no other reliable way of accomplishing this



(The situation we had was the original program was designed for a 640x480 screen, and the

entire OnInitDialog handler had MoveWindow calls with absolute positions in them. Then

all their customers got 800x600 monitors, but wanted the app to run full-screen, and it

was absolutely insane. It didn't help that a lot of the laptops of those days did not

support 256 colors and the fancy background used a 256-color bitmap. My own display was

already 1024x768, and I explained that every display was going to require a new bitmap and

massive changes in the program, most likely the thing to do would be to create a

configuration map that mapped controls to rectangles and this, too, would be a maintenance

nightmare. Given I was about to add 50 controls to the dialog to add the features they

wanted (in addition to the 800x600 enhancement) I considered this whole plan to be a truly

abysmal design. I still consider it abysmal design)

joe



On Tue, 17 Jul 2007 08:08:02 -0700, Golum256 <Golum256@discussions.microsoft.com>wrote:



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