Enable/Disable controls dynamically

[AntwanSherif]

I want to limit the user to only draw one polygon at a time. If they want to add another one they have to delete it first and then redraw another one.

To achieve this, I have an internal state used as a flag of whether to show or hide "polygonControl", but the component is not re-rendering, which makes the polygon control always displayed.

Is there any shortcut to achieve this? Or even better to disable the polygon button dynamically?