我想通过值而不是索引在JComboBox中设置选定的索引。怎么做？示例publicclassComboItem{privateStringvalue;privateStringlabel;publicComboItem(Stringvalue,Stringlabel){this.value=value;this.label=label;}publicStringgetValue(){returnthis.value;}publicStringgetLabel(){returnthis.label;}@OverridepublicStringtoString(){returnlabel;
