code: @Override
      public void setEnabled(boolean enabled) {
          if (enabled == false) {
              closePopup();
          }
          setTextFieldToValidStateIfNeeded();
          super.setEnabled(enabled);
          toggleTimeMenuButton.setEnabled(enabled);
          timeTextField.setEnabled(enabled);
          zDrawTextFieldIndicators();
      }
docs: setEnabled, This enables or disables the time picker. When the time picker is enabled, times
  can be selected by the user using any methods that are allowed by the current settings. When
  the time picker is disabled, there is no way for the user to interact with the component.
  More specifically, times cannot be selected with the mouse, or with the keyboard, and the
  time picker components change their color scheme to indicate the disabled state. Any
  currently stored text and last valid time values are retained while the component is
  disabled.