You could set the caption label to the value.

1. /**
2.  * ControlP5 Knob
3.  * by andreas schlegel, 2009
4.  */
5.  
6. import controlP5.*;
7. ControlP5 controlP5;
8. int myColorBackground = color(0,0,0);
9. int knobValue = 100;
10. Knob myKnobA;
11. Knob myKnobB;
12. void setup() {
13.   size(400,400);
14.   smooth();
15.   controlP5 = new ControlP5(this);
16.   myKnobA = controlP5.addKnob("knob",0,360,0,100,160,40);
17.   myKnobA.setCaptionLabel(""+myKnobA.getValue());
18.   myKnobB = controlP5.addKnob("knobValue",100,200,128,100,240,40);
19.   myKnobB.setCaptionLabel(""+myKnobB.getValue());
20.   myKnobA.setOffsetAngle(-HALF_PI);
21. }
22. void draw() {
23.   background(myColorBackground);
24.   fill(knobValue);
25.   rect(0,0,width,100);
26. }
27. void knob(int theValue) {
28.   myColorBackground = color(theValue);
29.   myKnobA.setCaptionLabel(""+theValue);
30.   println("a knob event. setting background to "+theValue);
31. }
32. void knobValue(int theValue) {
33.   myKnobB.setCaptionLabel(""+theValue);
34. }
35. void keyPressed() {
36.   myKnobA.setValue(180);
37. }

It gives an error message:


    The fonction getValue() does not exist.

I think current release probably has it as .value(), but it's been depreciated in recent builds in favor of getValue().  Sorry for the confusion.

Anyway it gives me an idea, thank you Jeff.

I had written that last bit from my phone, so sorry for not including the complete instruction.  You can download the latest version that works with the above code from Google code.  Otherwise, there is probably a few lines in there that might not work, such as setCaptionLabel() is probably just setLabel().  In any case, setting the value to the control label should do what you want.

I'm actually using the last version (0.6.12) but still it's not working.