Java 如何从FilteredList中删除项目?
我正在使用JavaFX8。我尝试过滤一个TableView,我做到了,但我还有一些其他功能,比如修改和删除表中的项目。添加过滤后,修改工作正常,但不支持删除!! 这是我实施的:Java 如何从FilteredList中删除项目?,java,javafx,Java,Javafx,我正在使用JavaFX8。我尝试过滤一个TableView,我做到了,但我还有一些其他功能,比如修改和删除表中的项目。添加过滤后,修改工作正常,但不支持删除!! 这是我实施的: public void setMainApp(MainApp mainApp) { this.mainApp = mainApp; refreshCategories(); FilteredList<Product> filteredProducts = new FilteredLi
public void setMainApp(MainApp mainApp) {
this.mainApp = mainApp;
refreshCategories();
FilteredList<Product> filteredProducts = new FilteredList<>(mainApp.getProductData(), p -> true);
categoryCombo.getSelectionModel().selectedItemProperty().addListener((observable, oldValue, newValue) -> {
filteredProducts.setPredicate(product -> {
if (newValue == null || newValue.isEmpty() || newValue.equals("None"))
return true;
String lowerCaseFilter = newValue.toLowerCase();
if (product.getCategory().toLowerCase().indexOf(lowerCaseFilter) == -1) {
return false;
}
return true;
});
});
productTable.setItems(filteredProducts);
}
这是导致异常的行:
productTable.getItems().remove(selectedIndex);
最后,这是异常消息:
Exception in thread "JavaFX Application Thread" java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1762)
at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(FXMLLoader.java:1645)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
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:49)
at javafx.event.Event.fireEvent(Event.java:198)
at javafx.scene.Node.fireEvent(Node.java:8216)
at javafx.scene.control.Button.fire(Button.java:185)
at com.sun.javafx.scene.control.behavior.ButtonBehavior.mouseReleased(ButtonBehavior.java:182)
at com.sun.javafx.scene.control.skin.BehaviorSkinBase$1.handle(BehaviorSkinBase.java:96)
at com.sun.javafx.scene.control.skin.BehaviorSkinBase$1.handle(BehaviorSkinBase.java:89)
at com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(CompositeEventHandler.java:218)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:80)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
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:198)
at javafx.scene.Scene$MouseHandler.process(Scene.java:3724)
at javafx.scene.Scene$MouseHandler.access$1500(Scene.java:3452)
at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1728)
at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2461)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:348)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:273)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:382)
at com.sun.glass.ui.View.handleMouseEvent(View.java:553)
at com.sun.glass.ui.View.notifyMouse(View.java:925)
at com.sun.glass.ui.gtk.GtkApplication._runLoop(Native Method)
at com.sun.glass.ui.gtk.GtkApplication.lambda$null$45(GtkApplication.java:126)
at com.sun.glass.ui.gtk.GtkApplication$$Lambda$42/584634336.run(Unknown Source)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)
at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1759)
... 51 more
Caused by: java.lang.UnsupportedOperationException
at java.util.AbstractList.remove(AbstractList.java:161)
at dz.bilaldjago.homekode.controller.ProductOverviewController.handleDelete(ProductOverviewController.java:103)
... 61 more
我的主要问题是:只读列表是否可能接受修改而不接受删除!
我希望这是一个清晰明了的答案。我知道这是一个迟来的答案,但也许有人会发现它很有用。就在今天,我偶然发现了这个问题。我正在开发一个应用程序,它将成为一个小型商店的简单仓库管理器。主要部分是一个TableView组件,它可以通过添加、删除或过滤项来动态更新 事实上,您不能向FilteredList添加od remove items或从中删除items,因为它将抛出UnsupportedOperationException,即使对于操作本身,您将使用基本ObservableList将其包装。我们可以做的是分别保留TableView项的ObservableList和FilteredList,如果需要更新,则只更新第一个,然后将其包装在FilteredList中,然后将其用作TableView.setItems()方法的源 演示代码:
public class DynamicFilteredList {
@FXML
private TableView tableView;
@FXML
private TextField searchField;
private ObservableList tableItems;
private FilteredList filteredTableItems;
private void wrapListAndAddFiltering() {
//Wrap ObservableList into FilteredList
filteredTableItems = new FilteredList<>(tableItems, p -> true);
//Add change listener to searchField component to filter the table view
searchField.textProperty().addListener((observable, oldValue, newValue) -> {
filteredTableItems.setPredicate(item -> {
if (newValue == null || newValue.isEmpty()) {
return true;
}
String query = newValue.toLowerCase();
if (item.getName().toLowerCase().contains(query)) {
return true;
}
return false;
});
});
}
private void add(Item item) {
tableItems.add(item);
wrapListAndAddFiltering();
tableView.setItems(filteredTableItems);
}
private void remove(Item item) {
tableItems.remove(item);
wrapListAndAddFiltering();
tableView.setItems(filteredTableItems);
}
}
公共类动态过滤列表{
@FXML
私有TableView TableView;
@FXML
私有文本字段搜索字段;
私人可观察列表项目;
private FilteredList filteredTableItems;
私有void wrapListAndAddFiltering(){
//将ObservableList包装到FilteredList中
filteredTableItems=新的FilteredList(tableItems,p->true);
//将更改侦听器添加到searchField组件以筛选表视图
searchField.textProperty().addListener((可观察、旧值、新值)->{
filteredTableItems.setPredicate(项->{
if(newValue==null | | newValue.isEmpty()){
返回true;
}
字符串查询=newValue.toLowerCase();
if(item.getName().toLowerCase().contains(查询)){
返回true;
}
返回false;
});
});
}
专用作废添加(项目){
tableItems.添加(项目);
WraplistandFiltering();
tableView.setItems(filteredTableItems);
}
私人作废删除(项目){
tableItems。删除(项目);
WraplistandFiltering();
tableView.setItems(filteredTableItems);
}
}
我看到这种方法的主要缺点是,在非常大的列表的情况下,它可能会消耗资源(特别是内存),并且可能会对应用程序的整体性能产生负面影响。我也有同样的问题,我发现,您可以使用
myFilteredList.getSource()
在我的例子中,我使用了ObservableList,并且能够使用
myFilteredList.getSource().remove(itemReference);
我希望这会有所帮助
myFilteredList.getSource().remove(itemReference);