See http://forum.processing.org/topic/control-p5-textlabel-doesn-t-seem-to-erase-previous-value-when-value-is-changed

Thanks Chrisir, but unless I'm missing something that example doesn't help me change the label background color. I did see the  .setColorValue(0xffcccccc); method, which was very helpful and I can now use that to change the text color. However I still can't change the label background color - perhaps this control is always transparent?

Assuming you are already using the latest ControlP5 0.7.5...

Indeed there is no direct way to set the label background color.

There are three ways of setting the color of the text: setColor(), setColorValue() and setColorValueLabel()

When I try some trickery it says: "WARNING: Image-based or custom displays are not yet implemented for this type of controller. (controlP5.Textlabel)". So the alternative is to get the position and dimensions and manually display a rect. As it turns out the getWidth() and getHeight() methods are returning incorrect values at the moment. If you want, you can file a bug for this so Andreas knows about it. The getPosition() works and with some magic numbers for the width and height of the rect, you can manually create a 'label background'. It's a bit of a workaround, but perhaps it serves your purpose. See the example below.

Code Example

1. import controlP5.*;
2. ControlP5 cp5;
3.  
4. Textlabel myTextlabelA;
5. Textlabel myTextlabelB;
6. Textlabel myTextlabelC;
7.  
8. void setup() {
9.   size(700,400);
10.   cp5 = new ControlP5(this);
11.  
12.   myTextlabelA = cp5.addTextlabel("labelA")
13.                     .setText("A single ControlP5 textlabel, in red.")
14.                     .setPosition(100,50)
15.                     .setColor(0xffff0000)
16.                     .setFont(createFont("Georgia",20))
17.                     ;
18.  
19.   myTextlabelB = cp5.addTextlabel("labelB")
20.                     .setText("A single ControlP5 textlabel, in green.")
21.                     .setPosition(100,150)
22.                     .setColorValue(color(0,255,0))
23.                     .setFont(createFont("Georgia",20))
24.                     ;
25.  
26.   myTextlabelC = cp5.addTextlabel("labelC")
27.                     .setText("A single ControlP5 textlabel, in blue.")
28.                     .setPosition(100,250)
29.                     .setColorValueLabel(0xff0000ff)
30.                     .setFont(createFont("Georgia",20))
31.                     ;
32. }
33.  
34. void draw() {
35.   background(0);
36.   PVector pos = myTextlabelB.getPosition();
37.   fill(125);
38.   rect(pos.x, pos.y, 345, 28); // manually width & height since the methods don't work properly
    
39. }