Handling DPI changes in my vb6 app
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From: Mojo on 14 Jun 2010 05:53 Hi All I have created a multiple form app (only shows 1 form at a time though!) and it looks and works fine on most Win2000 - 7 machines. However, if a machine has been set up for any other dpi than the default setting of 96dpi (eg 120dpi) then my app has a huge grey appendedge to it and all of the buttons, scrollbars, etc go awol. I have to be a genius with the old mouse and click into nothingness to get the app to quit or do a Ctrl+Alt+Del job. I have to do this as the app is completely unusable yet all other apps seem fine. Did I miss something in programming pre-school??? Is there no way I can just have my app at a desired set size irrespective of the dpi? Thanks
From: BeeJ on 14 Jun 2010 12:51 "Mojo" <please(a)dont.spam.com> wrote in message news:1dGdnZXvecWmYYjRnZ2dnUVZ7oCdnZ2d(a)brightview.co.uk... > Hi All > > I have created a multiple form app (only shows 1 form at a time though!) > and > it looks and works fine on most Win2000 - 7 machines. > > However, if a machine has been set up for any other dpi than the default > setting of 96dpi (eg 120dpi) then my app has a huge grey appendedge to it > and all of the buttons, scrollbars, etc go awol. > > I have to be a genius with the old mouse and click into nothingness to get > the app to quit or do a Ctrl+Alt+Del job. I have to do this as the app is > completely unusable yet all other apps seem fine. > > Did I miss something in programming pre-school??? > > Is there no way I can just have my app at a desired set size irrespective > of > the dpi? > > Thanks > > Hmmm ... My Windows Vista Ultimate is set to 120 DPI (always has been) and I have no issues as you describe with any of the VB6 apps that I created. I use all available controls and even have some that I created. No problems. Maybe it is your display adapter/driver? Have you tried on other PCs with them set to 120 DPI or otherwise? I do have one app that does have similar issues, but that is a commercial app produced by Punch software (Home Design).
From: Helmut Meukel on 14 Jun 2010 14:26 "BeeJ" <beejuice(a)live.com> schrieb im Newsbeitrag news:hv5mpf$5u3$1(a)news.eternal-september.org... > > "Mojo" <please(a)dont.spam.com> wrote in message > news:1dGdnZXvecWmYYjRnZ2dnUVZ7oCdnZ2d(a)brightview.co.uk... >> Hi All >> >> I have created a multiple form app (only shows 1 form at a time though!) and >> it looks and works fine on most Win2000 - 7 machines. >> >> However, if a machine has been set up for any other dpi than the default >> setting of 96dpi (eg 120dpi) then my app has a huge grey appendedge to it >> and all of the buttons, scrollbars, etc go awol. >> >> I have to be a genius with the old mouse and click into nothingness to get >> the app to quit or do a Ctrl+Alt+Del job. I have to do this as the app is >> completely unusable yet all other apps seem fine. >> >> Did I miss something in programming pre-school??? >> >> Is there no way I can just have my app at a desired set size irrespective of >> the dpi? >> >> Thanks >> >> > Hmmm ... My Windows Vista Ultimate is set to 120 DPI (always has been) and I > have no issues as you describe with any of the VB6 apps that I created. I use > all available controls and even have some that I created. No problems. > Maybe it is your display adapter/driver? Have you tried on other PCs with > them set to 120 DPI or otherwise? > I do have one app that does have similar issues, but that is a commercial app > produced by Punch software (Home Design). > > I've seen such behavior in some non-VB6 apps and once in an VB3 app I wrote years back. (AFAIK it would have been the same with VB6). But this was a special case, there was no problem with any of the intrinsic controls. I used a huge PictureBox to display a drawing of a waste-water heat regeneration system with tanks, pipes, valves, pumps. I had used an InvisibleButton control put over the places in the drawing where the pumps and valves were. So the user could switch to 'manual mode' and click onto a valve or pump and it changed its state - open/closed, stopped/running. The positions and sizes of the InvisibleButtons were set at design-time in twips, while the drawing used pixels. This was no problem - the program was used on only one machine - until the customer replaced the display unit and changed the dpi setting. With the resulting other TwipsPerPixel ratio the InvisibleButtons were too small and in the wrong place. What the customer baffled was that some pumps and valves still worked while others didn't react at all. Those in the top left corner worked, for the others you had to guess where to click. So if the OP is working with different units (twips, pixels, himetrics) without correcting positions and sizes due to the different dpi settings he is in trouble. Helmut.
From: Schmidt on 14 Jun 2010 15:27 "Helmut Meukel" <Helmut_Meukel(a)NoProvider.de> schrieb im Newsbeitrag news:hv5s88$n95$1(a)news.eternal-september.org... [industrial GUI-controls] > This was no problem - the program was used on only > one machine - until the customer replaced the display > unit and changed the dpi setting. > With the resulting other TwipsPerPixel ratio the InvisibleButtons were > too small and in the wrong place. > What the customer baffled was that some pumps and valves > still worked while others didn't react at all. Those in the > top left corner worked, for the others you had to guess > where to click. Uff, may I ask, if this by any chance was used in some "atomic power plant"? ;-) D&R (in the true sense) <g> Olaf
From: Helmut Meukel on 14 Jun 2010 16:57
"Schmidt" <sss(a)online.de> schrieb im Newsbeitrag news:hv5vqc$t81$1(a)speranza.aioe.org... > > "Helmut Meukel" <Helmut_Meukel(a)NoProvider.de> schrieb im Newsbeitrag > news:hv5s88$n95$1(a)news.eternal-september.org... > > [industrial GUI-controls] >> This was no problem - the program was used on only >> one machine - until the customer replaced the display >> unit and changed the dpi setting. >> With the resulting other TwipsPerPixel ratio the InvisibleButtons were >> too small and in the wrong place. >> What the customer baffled was that some pumps and valves >> still worked while others didn't react at all. Those in the >> top left corner worked, for the others you had to guess >> where to click. > > Uff, may I ask, if this by any chance was used in some > "atomic power plant"? ;-) > > D&R (in the true sense) <g> > > Olaf > No, normally the program ran in 'automatic mode', which meant it just displayed actual values it got from the PLC which did all the work. In 'manual mode' the user could start/stop pumps und open/close valves by clicking on the display. The VB program did however only transfer these user actions to the PLC and the PLC processed them -- if they were valid. That is it checked if the desired action was within the safety bounds of its program. Helmut. BTW, I programmed this in 1993 in VB3 running on a NT3.51 box. About 2001 I upgraded it to VB6 without any substantial change and it was used til autumn 2008, when they shut-down the plant. |