dat.gui/src/DAT/GUI/ControllerBoolean.js

DAT.GUI.ControllerBoolean = function() {

  this.type = "boolean";
  DAT.GUI.Controller.apply(this, arguments);

  var _this = this;
  var input = document.createElement('input');
  input.setAttribute('type', 'checkbox');

  input.checked = this.getValue();
  this.setValue(this.getValue());

  this.domElement.addEventListener('click', function(e) {
    input.checked = !input.checked;
    e.preventDefault();
    _this.setValue(input.checked);
  }, false);

  input.addEventListener('mouseup', function(e) {
    input.checked = !input.checked; // counteracts default.
  }, false);

  this.domElement.style.cursor = "pointer";
  this.propertyNameElement.style.cursor = "pointer";
  this.domElement.appendChild(input);

  this.updateDisplay = function() {
    input.checked = _this.getValue();
  };


  this.setValue = function(val) {
    if (typeof val != "boolean") {
      try {
        val = eval(val);
      } catch (e) {
      }
    }
    return DAT.GUI.Controller.prototype.setValue.call(this, val);
  };

};
DAT.GUI.extendController(DAT.GUI.ControllerBoolean);