Delphi – Disabling progress bar animation on Vista Aero

aerodelphiprogress-barvclwindows-vista

I'm using a Delphi 2009 VCL TProgressBar as a kind of "empty/full" gauge.

On Vista, with Aero theme enabled, this has an animation associated with it, which is annoying and inappropriate for an gauge.

Is there any way of disabling this (NOT by adjusting user's theme settings!) to prevent the animation on this control?

To clarify, I want something basically identical to the 'disk space used' meters in Windows Explorer. No animation, but still with a nice border and shading effects.

Update:

I understand that I need a "meter", rather than a true progress bar. How can a themed meter be implemented using the standard windows progress bar control?

Best Answer

As per the Vista UI guidelines for progress bars you should not be using a TProgressBar for such purposes at all, it states:

Use progress bars only for progress. Use meters to indicate percentages that aren't related to progress.

There are a lot of Third-Party components (for example Abakus VCL) that are aimed at Process Automation applications and the like, maybe you could use one of these controls instead?

Related Solutions

R – How to programmatically disable window animation under Vista Aero

The link in the comment from Shoban led me in the right direction. A quick check showed a wrapper for the DwmApi in the VCL and from that it went straight forward. Here is the code I successfully use now:

uses DwmApi;
...
  SaveDwmCompositionEnabled := DwmCompositionEnabled;
  if SaveDwmCompositionEnabled then
    DwmEnableComposition(DWM_EC_DISABLECOMPOSITION);
...
  if SaveDwmCompositionEnabled then
    DwmEnableComposition(DWM_EC_ENABLECOMPOSITION);

Windows 7 Aero Theme Progress Bar Bug

It has to do with the animation of the progress bar. If your progress bar is at 0% and you set it to 100% then it will not jump there, but animate the progress bar smoothly filling up. If this is too slow, you will be done before the progress bar finished animating. So even though you have already set it to 80, 90 and 100%, the animation still lags behind.

I never found a way to turn this off, however I have a workaround. The animation is only being done if you increment the progress bar. If you move it backwards, it will immediately jump to that position. So if I want the progress bar to be at x% (x != 100) then I move it to x+1 and then to x. If I want it at 100% I move it to 100, 99 and 100%. (Or whatever values you use, you get the idea.) This works fast enough to not to be visible, and you can leave this code in for previous Windows versions as well (though I don't).

Best Answer

Related Solutions

R – How to programmatically disable window animation under Vista Aero

Windows 7 Aero Theme Progress Bar Bug

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