我需要一个显示客户名称的组合框，并在选择其中一个项目时给予customerId。组合框我意识到正确的方式工作，但当它失去焦点，或者我按下回车键时，我收到以下错误：
Exception in thread "JavaFX Application Thread" java.lang.ClassCastException: java.lang.String cannot be cast to kinema.classi.NomeCodice
at kinema.ASediController$1.changed(ASediController.java:104)
at com.sun.javafx.binding.ExpressionHelper$Generic.fireValueChangedEvent(ExpressionHelper.java:347)
at com.sun.javafx.binding.ExpressionHelper.fireValueChangedEvent(ExpressionHelper.java:80)
at javafx.beans.property.ReadOnlyObjectWrapper$ReadOnlyPropertyImpl.fireValueChangedEvent(ReadOnlyObjectWrapper.java:176)
at javafx.beans.property.ReadOnlyObjectWrapper.fireValueChangedEvent(ReadOnlyObjectWrapper.java:142)
at javafx.beans.property.ObjectPropertyBase.markInvalid(ObjectPropertyBase.java:112)
at javafx.beans.property.ObjectPropertyBase.set(ObjectPropertyBase.java:145)
at javafx.scene.control.SelectionModel.setSelectedItem(SelectionModel.java:102)
at javafx.scene.control.ComboBox$2.changed(ComboBox.java:221)
at com.sun.javafx.binding.ExpressionHelper$Generic.fireValueChangedEvent(ExpressionHelper.java:347)
at com.sun.javafx.binding.ExpressionHelper.fireValueChangedEvent(ExpressionHelper.java:80)
at javafx.beans.property.ObjectPropertyBase.fireValueChangedEvent(ObjectPropertyBase.java:105)
at javafx.beans.property.ObjectPropertyBase.markInvalid(ObjectPropertyBase.java:112)
at javafx.beans.property.ObjectPropertyBase.set(ObjectPropertyBase.java:145)
at javafx.scene.control.ComboBoxBase.setValue(ComboBoxBase.java:167)
at com.sun.javafx.scene.control.skin.ComboBoxListViewSkin.setTextFromTextFieldIntoComboBoxValue(ComboBoxListViewSkin.java:512)
at com.sun.javafx.scene.control.skin.ComboBoxListViewSkin.access$200(ComboBoxListViewSkin.java:57)
at com.sun.javafx.scene.control.skin.ComboBoxListViewSkin$3.handle(ComboBoxListViewSkin.java:162)
at com.sun.javafx.scene.control.skin.ComboBoxListViewSkin$3.handle(ComboBoxListViewSkin.java:150)
at com.sun.javafx.event.CompositeEventHandler$NormalEventFilterRecord.handleCapturingEvent(CompositeEventHandler.java:282)
at com.sun.javafx.event.CompositeEventHandler.dispatchCapturingEvent(CompositeEventHandler.java:98)
at com.sun.javafx.event.EventHandlerManager.dispatchCapturingEvent(EventHandlerManager.java:223)
at com.sun.javafx.event.EventHandlerManager.dispatchCapturingEvent(EventHandlerManager.java:180)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchCapturingEvent(CompositeEventDispatcher.java:43)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:52)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54)
at javafx.event.Event.fireEvent(Event.java:204)
at javafx.scene.Scene$KeyHandler.process(Scene.java:3949)
at javafx.scene.Scene$KeyHandler.access$2100(Scene.java:3896)
at javafx.scene.Scene.impl_processKeyEvent(Scene.java:2036)
at javafx.scene.Scene$ScenePeerListener.keyEvent(Scene.java:2493)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$KeyEventNotification.run(GlassViewEventHandler.java:170)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$KeyEventNotification.run(GlassViewEventHandler.java:123)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleKeyEvent(GlassViewEventHandler.java:197)
at com.sun.glass.ui.View.handleKeyEvent(View.java:517)
at com.sun.glass.ui.View.notifyKey(View.java:927)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.access$300(WinApplication.java:39)
at com.sun.glass.ui.win.WinApplication$4$1.run(WinApplication.java:112)
at java.lang.Thread.run(Thread.java:744)
以下是错误的行代码:( ASediController.java:104行代码）。
ComboAzienda.getSelectionModel().selectedItemProperty().addListener(new ChangeListener<NomeCodice>() {
@Override
public void changed(ObservableValue<? extends NomeCodice> selected,
NomeCodice VecchiaAzienda, NomeCodice NuovaAzienda) {
try {
CaricaAzienda(NuovaAzienda.getIdCodice());
} catch (SQLException ex) {
Logger.getLogger(ASediController.class.getName()).log(Level.SEVERE, null, ex);
}
}
});
这是Nomecodice类：
public class NomeCodice {
private int TIdCodice;
private String TDenominazione ;
public NomeCodice(String Denominazione,int IdCodice) {
this.TDenominazione = Denominazione;
this.TIdCodice = IdCodice;
}
public int getIdCodice() {
return TIdCodice;
}
public void setIdCodice(int fCodice) {
TIdCodice= fCodice;
}
public String getTDenominazione() {
return TDenominazione;
}
public void setTDenominazione(String fDenominazione) {
TDenominazione = fDenominazione;
}
@Override
public String toString() {
return TDenominazione ;
}
}
我是java的新手，所以我很确定这是我的错误，但我无法找到它。您的建议将不胜感激。
答案 0 :(得分：3)
您的ComboBox是可编辑的，但您没有为StringConverter提供正确的ComboBox转换器。像这样设置转换器属性：
ComboAzienda.setConverter(new StringConverter<NomeCodice>() {
@Override
public String toString(NomeCodice object) {
if (object == null) return null;
return object.toString();
}
@Override
public NomeCodice fromString(String string) {
// replace this with approquiate implementation of parsing function
// or lookup function
return new NomeCodice(string, 0);
}
});
至少我可以找到尝试重现错误的内容。
当然，防止出现错误的一种更简单的方法是使ComboBox不可编辑，但我认为您是故意编辑的。