A visual widget that shows the progress of a task or an operation. It appears as a bar that fills up gradually, representing the completion status of a process.
local progress = ProgressBar()
.. function:: setRange(start, end) :noindex: Sets the progress range
.. function:: setValue(value) Sets the current value
.. function:: getValue() Returns the current value
.. function:: setOrientation(orientation) Sets the orientation: ``horizontal`` or ``vertical``