class_docstr: WidgetParameterItem subclass providing comboBox that lets the user select from a list of options.
class_docstr_tok: ["WidgetParameterItem","subclass","providing","comboBox","that","lets","the","user","select","from","a","list","of","options","."]
code: def limitsChanged(self, param, limits):
      # set up forward / reverse mappings for name:value
  
      if len(limits) == 0:
          limits = [
              ""
          ]  ## Can never have an empty list--there is always at least a singhe blank item.
  
      self.forward, self.reverse = ListParameter.mapping(limits)
      try:
          self.widget.blockSignals(True)
          val = self.targetValue
  
          self.widget.clear()
          for k in self.forward:
              self.widget.addItem(k)
              if k == val:
                  self.widget.setCurrentIndex(self.widget.count() - 1)
                  self.updateDisplayLabel()
      finally:
          self.widget.blockSignals(False)
  
file_path: pyqtgraph/pyqtgraph/parametertree/parameterTypes/list.py
imports: import warnings
  from collections import OrderedDict
  from ...None import functions
  from ...Qt import QtWidgets
  from ..Parameter import Parameter
  from .basetypes import WidgetParameterItem
label_desc: Use image node_id 5 for calling the ListParameterItem obj's underlying member method code with example usage: obj.limitsChanged(param, limits) without return types