Set Text On Existing Instance

[chitgoks]

Is your feature request related to a problem? Please describe.
Once i have created a progress dialog, there is no way to set the label.

Describe the solution you'd like
I am using this dialog to do more than 1 task so a way to be able to change the existing text would be nice.

[fayaz07]

@chitgoks , please read the docs first, unnecessarily don't create issues here. There is already a method called update is provided. Go ahead and read docs first.