Progress Bar Cancel?


We are developing a new command that can take a while to execute and so we want to add a progress bar and the option to cancel the operation. I see that there is the ShowProgressMeter() ( ) method which can be used to display a progress meter in the status bar, but there doesn’t seem to be a built-in way to cancel a command or display a cancel button (next to the progress meter for example) in the RhinoCommon API.

My question is:
Can the the status bar / progress bar be customized using the Eto framework? Or do we need to create our own dialog with progress bar + cancel button if we want to have the cancel option?

Thank you.

Hi @benoit.deschenes, you might offer a condition to cancel (eg with ESC and observe the key press). Below example is using Python , should be similar in RhinoCommon.

import Rhino
import scriptcontext
import rhinoscriptsyntax as rs

def DoSomething():
    Rhino.UI.StatusBar.ShowProgressMeter(0, 5000, "Processing", True, True)
    Rhino.RhinoApp.SetCommandPrompt("Hold ESC To cancel")
    for i in xrange(5000):
        if scriptcontext.escape_test(False): 
        if i % 100 == 0: 
            Rhino.UI.StatusBar.UpdateProgressMeter(i, True)



Hi @clement,

Your’re right I could listen for some Keyboard input, but I’m more interested to know if there is a graphical UI option in the API for that kind of behavior, or if we have to code it ourselves if we need it.

Thank you.

Hi @benoit.deschenes, i don’t think there is something pre-canned. But you could do it like this:

  1. Setup a key value pair Cancel=False as document user string before the process starts*
  2. Start your process
  3. Open a modeless ETO Form with a single button. If the button is pressed, set Cancel=True
  4. In your process, check the value similar as i check for ESC press
  5. If Cancel is True, abort the process and hide the progress bar
  6. Set Cancel=False so it is functional for a next run

*instead of a user string, you might also use a global variable in C#

Leaving the final solution here for posterity:
We ended up using the RhinoApp.EscapeKeyPressed event in order to trigger our task cancellation, this does not require any additional UI creation.