Something like this should do it...
const var myKnob = Content.getComponent("myKnob");
const var myLabel = Content.getComponent("myLabel");
inline function onmyButtonControl(component, value)
{
if(value)
myKnob.setMode("TempoSync");
else
myKnob.setMode("Frequency");
};
Content.getComponent("myButton").setControlCallback(onmyButtonControl);
inline function onmyKnobControl(component, value)
{
local mode = myKnob.get("mode");
if(mode == "TempoSync")
myLabel.set("text", Engine.getTempoName(value));
else
myLabel.set("text", value + " Hz");
};
Content.getComponent("myKnob").setControlCallback(onmyKnobControl);