Group switching

This sketch demonstrates how to use group enable/disable to implement page or mode switching. This is useful when you have a limited number of physical controls but want them to serve different functions depending on the active mode.

In this example, a "mode" button switches between two groups:

• Group A: the potentiometer controls volume.
• Group B: the potentiometer controls filter cutoff.

Only one group is active at a time. The potentiometer is registered to both groups, but only the enabled group's handler fires.

The code

Copy#include <CtrlGroup.h>
#include <CtrlBtn.h>
#include <CtrlPot.h>

CtrlGroup volumeGroup;
CtrlGroup filterGroup;

CtrlPot knob(A0, 127, 0.5);

void onVolumeChange(Groupable& pot, int value) {
  Serial.print("Volume: ");
  Serial.println(value);
}

void onFilterChange(Groupable& pot, int value) {
  Serial.print("Filter: ");
  Serial.println(value);
}

void onModeSwitch() {
  if (volumeGroup.isEnabled()) {
    volumeGroup.disable();
    filterGroup.enable();
    knob.setGroup(&filterGroup);
    Serial.println("Switched to Filter mode");
  } else {
    filterGroup.disable();
    volumeGroup.enable();
    knob.setGroup(&volumeGroup);
    Serial.println("Switched to Volume mode");
  }
}

CtrlBtn modeButton(2, 15, onModeSwitch);

void setup() {
  Serial.begin(9600);

  volumeGroup.setOnValueChange(onVolumeChange);
  filterGroup.setOnValueChange(onFilterChange);

  knob.setGroup(&volumeGroup);

  // Start with volume mode active, filter mode disabled.
  volumeGroup.enable();
  filterGroup.disable();

  Serial.println("Volume mode active");
}

void loop() {
  modeButton.process();

  volumeGroup.process();
  filterGroup.process();
}