QProgressbar resets to -1

[Megamouse]

Hi,

I was wondering why our progressbars in the dialogs never reached the maximum.
The backend only increased the value by a delta, which was then handled in the dialog with something like:

myBar->SetValue(myBar->value() + delta);

As it turned out the Progressbar initializes with value = -1.
Why is that?

best,
Megamouse

[jsulm]

@Megamouse Is it possible that at some point

myBar->value() + delta

were bigger than what you set using setRange()?

[J.Hilk]

@jsulm actually from what I remember, set range does not change the current value.

e.g
value == 20 -> setRange(0,10) -> value still at 20

I don't know why its done, but creating a QProgressBar or calling reset() on an existing one will set the current value to -1;

I would assume that this is done, to allow the valueChanged() signal to be emitted when the value is set to 0?

[jsulm]

@J.Hilk I mean other way around: you set max to 10 and then setValue(11) - not sure what will happen.

[Megamouse]

@jsulm no the value wasn't exceeding the max. (but that was another issue later as you can read below)

I think this whole implementation is simply weird.

as J.Hilk said: the reset and init of any progressbar/dialog set the value to minimum-1 (apart from the QWinTaskBarProgress).

Also apart from that... any increase/decrease above/below the min and max just returns without doing anything.....
I think that is just wrong. the progressbar should always increase until max is reached. There is no logical explanation for this choice of implementation ...