如何处理ListView项目单击操作？ [英] How to handle ListView item clicked action?

问题描述

我有我的JavaFX 2.0应用程序，在用户单击ListView元素中的项目后，我需要做一些操作。为了构建用户GUI我正在使用FXML，其中我有这样的东西：

I have my JavaFX 2.0 application, where i need to make some action, after user clicked an item in ListView element. To construct user GUI i'm using FXML, in which i have something like this:

        <children>
            <ListView fx:id="listView" GridPane.columnIndex="0" 
            GridPane.rowIndex="1" labelFor="$pane" 
            onPropertyChange="#handleListViewAction"/>
        </children>

以下是我在此次活动的控制器中所拥有的内容：

And here is what i have in a Controller for this event:

        @FXML protected void handleListViewAction(ActionEvent event) {
           System.out.println("OK");
        }

这是一个错误，我接受，当场景，这是这个gui是构造的：

And here is an error, i recieve, when the scene, which is for this gui is constructed:

javafx.fxml.LoadException: java.lang.String does not define a property model for "property".
at javafx.fxml.FXMLLoader$Element.processEventHandlerAttributes(Unknown Source)
at javafx.fxml.FXMLLoader$ValueElement.processEndElement(Unknown Source)
at javafx.fxml.FXMLLoader.processEndElement(Unknown Source)
at javafx.fxml.FXMLLoader.load(Unknown Source)
at javafx.fxml.FXMLLoader.load(Unknown Source)
at javafx.fxml.FXMLLoader.load(Unknown Source)
at fxmlexample.FXMLExampleController.handleSubmitButtonAction(FXMLExampleController.java:49)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(Unknown Source)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
at com.sun.javafx.event.EventUtil.fireEventImpl(Unknown Source)
at com.sun.javafx.event.EventUtil.fireEvent(Unknown Source)
at javafx.event.Event.fireEvent(Unknown Source)
at javafx.scene.Node.fireEvent(Unknown Source)
at javafx.scene.control.Button.fire(Unknown Source)
at com.sun.javafx.scene.control.behavior.ButtonBehavior.mouseReleased(Unknown Source)
at com.sun.javafx.scene.control.skin.SkinBase$5.handle(Unknown Source)
at com.sun.javafx.scene.control.skin.SkinBase$5.handle(Unknown Source)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
at com.sun.javafx.event.EventUtil.fireEventImpl(Unknown Source)
at com.sun.javafx.event.EventUtil.fireEvent(Unknown Source)
at javafx.event.Event.fireEvent(Unknown Source)
at javafx.scene.Scene$MouseHandler.process(Unknown Source)
at javafx.scene.Scene$MouseHandler.process(Unknown Source)
at javafx.scene.Scene$MouseHandler.access$1300(Unknown Source)
at javafx.scene.Scene.impl_processMouseEvent(Unknown Source)
at javafx.scene.Scene$ScenePeerListener.mouseEvent(Unknown Source)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(Unknown Source)
at com.sun.glass.ui.View.handleMouseEvent(Unknown Source)
at com.sun.glass.ui.View.notifyMouse(Unknown Source)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.access$100(Unknown Source)
at com.sun.glass.ui.win.WinApplication$2$1.run(Unknown Source)
at java.lang.Thread.run(Thread.java:722) java.lang.NullPointerException
at javafx.scene.Scene.doCSSPass(Unknown Source)
at javafx.scene.Scene.access$2900(Unknown Source)
at javafx.scene.Scene$ScenePulseListener.pulse(Unknown Source)
at com.sun.javafx.tk.Toolkit.firePulse(Unknown Source)
at com.sun.javafx.tk.quantum.QuantumToolkit.pulse(Unknown Source)
at com.sun.javafx.tk.quantum.QuantumToolkit$8.run(Unknown Source)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.access$100(Unknown Source)
at com.sun.glass.ui.win.WinApplication$2$1.run(Unknown Source)
at java.lang.Thread.run(Thread.java:722)

此异常的最后一个块（来自此处java.lang.NullPointerException）是循环的。

And the last block of this exception (from here java.lang.NullPointerException) is looped.

推荐答案

FXML属性和值直接映射到FX API。因此，要了解如何编写处理程序，您可以首先通过API创建所需的实体。

FXML attributes and values are directly mapped to FX API. So to find out how to write handler you can first create required entities by API.

似乎您想在鼠标单击时在ListView元素上添加操作，因此您需要添加鼠标单击处理程序在API中它看起来是下一个方式：

It seems you want to add action on ListView element on mouse click, so you need to add mouse click handler. In API it looks next way:

    final ListView lv = new ListView(FXCollections.observableList(Arrays.asList("one", "2", "3")));
    lv.setOnMouseClicked(new EventHandler<MouseEvent>() {

        @Override
        public void handle(MouseEvent event) {
            System.out.println("clicked on " + lv.getSelectionModel().getSelectedItem());
        }
    });

查看该代码，您可以找到FXML中需要覆盖的属性 onMouseClicked ：

Looking at that code you can find out what in FXML you need to overrided attribute onMouseClicked:

<ListView fx:id="listView" onMouseClicked="#handleMouseClick"/>

在控制器中你需要提供处理程序 MouseEvent 参数：

And in controller you need to provide handler with MouseEvent parameter:

@FXML
private ListView listView;

@FXML public void handleMouseClick(MouseEvent arg0) {
    System.out.println("clicked on " + listView.getSelectionModel().getSelectedItem());
}

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