How do I use ProgressEventHandler?

[xchellx]

How exactly do I use ProgressEventHandler? There is only a progress value for ProgressEventArgs. There is no way to get and set the max progress...

[otuncelli]

Its range is from 0 to 100 (percentage). AFAIK, There is no max value setter. You need to do the calculations.

[xchellx]

@otuncelli How do I set the max size that way?

[Rick Brewster]

You don't set the max size. You report progress from 0 to 100.

[otuncelli]

ProgressEventArgs should have taken integer parameter, not double. The precision doesn't get used. Paint.NET UI doesn't show decimal places when saving.

 

1. progress = (current_index / maximum) * 100

2 Then round this value to nearest integer

3. Check the value if it equals to the previous calls' progress value.

4. If it's not equal, call the event handler, otherwise don't call it. Because you wouldn't want to call the event handler too frequently with the same values. This would just make UI thread busy and slows down the process. I don't know if Paint.NET prevents unnecessary calls here.

Edited January 19, 2022 by otuncelli

[xchellx]

@otuncelli Thank you 👍

[Rick Brewster]

2 hours ago, otuncelli said:

2 Then round this value to nearest integer

3. Check the value if it equals to the previous calls' progress value.

4. If it's not equal, call the event handler, otherwise don't call it. Because you wouldn't want to call the event handler too frequently with the same values. This would just make UI thread busy and slows down the process. I don't know if Paint.NET prevents unnecessary calls here.

 

Don't worry about these. Paint.NET already does the right thing here.

[midora]

The progress handler allows paint.net to throw the OperationCanceledException (if SupportsCancellation is set). This may be important to allow a fluid change of parameters by the user if the save operation is slow and/or the image is quite large. So you should not suppress progress calls.

 

I'm happy that the progress parameter is not an int. This allows to show a higher granulation without an interface change.