item state chang item event object target target object old valu model facad multipl target note multipl combo box target set caus event user action sure consid chang follow logic state chang item event select combo text multipl combo box select item old valu combo text equal model facad old valu object multi model data type factori creat multipl combo text multi model core helper set multipl target model core helper set multipl target multi old valu model uml factori delet old valu multipl combo box set enabl multipl combo box set edit multipl combo box set enabl multipl combo box set edit model core helper set multipl target old valu model uml factori delet old valu 