错误 javafx：未指定页面语言

Question

我用 JAVAFx 制作了一个图形界面，在 NETBEANS 7.3.1 上，我遇到了问题；堆栈跟踪是

Executing com.javafx.main.Main from C:\Users\Guillaume\Documents\NetBeansProjects4\JavaFXApplication1\dist\run1976733325\JavaFXApplication1.jar using platform C:\Program Files\Java\jdk1.7.0_80/bin/java
Page language not specified.
file:/C:/Users/Guillaume/Documents/NetBeansProjects4/JavaFXApplication1/dist/run1976733325/JavaFXApplication1.jar!/javafxapplication1/Sample.fxml:30
  at javafx.fxml.FXMLLoader$Element.processEventHandlerAttributes(FXMLLoader.java:510)
  at javafx.fxml.FXMLLoader$ValueElement.processEndElement(FXMLLoader.java:594)
  at javafx.fxml.FXMLLoader.processEndElement(FXMLLoader.java:2472)
  at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2177)
  at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2069)
  at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2830)
  at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2809)
  at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2795)
  at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2782)
  at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2771)
  at javafxapplication1.JavaFXApplication1.start(JavaFXApplication1.java:21)
  at com.sun.javafx.application.LauncherImpl$5.run(LauncherImpl.java:319)
  at com.sun.javafx.application.PlatformImpl$5.run(PlatformImpl.java:219)
  at com.sun.javafx.application.PlatformImpl$4$1.run(PlatformImpl.java:182)
  at com.sun.javafx.application.PlatformImpl$4$1.run(PlatformImpl.java:179)
  at java.security.AccessController.doPrivileged(Native Method)
  at com.sun.javafx.application.PlatformImpl$4.run(PlatformImpl.java:179)
  at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:76)
  at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
  at com.sun.glass.ui.win.WinApplication.access$100(WinApplication.java:17)
  at com.sun.glass.ui.win.WinApplication$3$1.run(WinApplication.java:67)
  at java.lang.Thread.run(Thread.java:745)

Exception in Application start method
java.lang.reflect.InvocationTargetException
    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:606)
    at com.javafx.main.Main.launchApp(Main.java:698)
    at com.javafx.main.Main.main(Main.java:871)
Caused by: java.lang.RuntimeException: Exception in Application start method
    at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:403)
    at com.sun.javafx.application.LauncherImpl.access$000(LauncherImpl.java:47)
    at com.sun.javafx.application.LauncherImpl$1.run(LauncherImpl.java:115)
    at java.lang.Thread.run(Thread.java:745)
Caused by: javafx.fxml.LoadException: Page language not specified.
    at javafx.fxml.FXMLLoader$Element.processEventHandlerAttributes(FXMLLoader.java:510)
    at javafx.fxml.FXMLLoader$ValueElement.processEndElement(FXMLLoader.java:594)
    at javafx.fxml.FXMLLoader.processEndElement(FXMLLoader.java:2472)
    at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2177)
    at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2069)
    at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2830)
    at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2809)
    at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2795)
    at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2782)
    at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2771)
    at javafxapplication1.JavaFXApplication1.start(JavaFXApplication1.java:21)
    at com.sun.javafx.application.LauncherImpl$5.run(LauncherImpl.java:319)
    at com.sun.javafx.application.PlatformImpl$5.run(PlatformImpl.java:219)
    at com.sun.javafx.application.PlatformImpl$4$1.run(PlatformImpl.java:182)
    at com.sun.javafx.application.PlatformImpl$4$1.run(PlatformImpl.java:179)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.application.PlatformImpl$4.run(PlatformImpl.java:179)
    at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:76)
    at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
    at com.sun.glass.ui.win.WinApplication.access$100(WinApplication.java:17)
    at com.sun.glass.ui.win.WinApplication$3$1.run(WinApplication.java:67)
    ... 1 more
Java Result: 1

fxml 文件是：

<?xml version="1.0" encoding="UTF-8"?>

<?import java.lang.*?>
<?import java.util.*?>
<?import javafx.collections.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>

<AnchorPane id="AnchorPane" prefHeight="307.0" prefWidth="503.0" xmlns:fx="http://javafx.com/fxml/1" xmlns="http://javafx.com/javafx/2.2">
  <children>
    <Label id="lb_config" layoutX="14.0" layoutY="4.0" prefHeight="37.0" prefWidth="252.0" text="Configuration de compteurs SDM120" />
    <Label id="lb_select" layoutX="93.0" layoutY="70.0" text="Selection compteur adresse n°" />
    <Label id="lb_config_act" layoutX="82.0" layoutY="126.0" text="Configuration actuelle :" />
    <Label id="lb_vit" layoutX="93.0" layoutY="154.0" text="Vitesse de transmission" />
    <Label id="lb_tps" layoutX="208.0" layoutY="203.0" text="Temps" />
    <Label id="lb_imp" layoutX="134.0" layoutY="244.0" text="Sortie à impulsion" />
    <Button fx:id="bt_modif" layoutX="364.0" layoutY="273.0" mnemonicParsing="false" text="Modifier" />
    <TextField fx:id="tf_vit" layoutX="281.0" layoutY="154.0" prefWidth="200.0" />
    <TextField fx:id="tf_tps" layoutX="281.0" layoutY="203.0" prefWidth="200.0" />
    <TextField fx:id="tf_imp" layoutX="281.0" layoutY="241.0" prefWidth="200.0" />
    <ComboBox fx:id="me_sel" layoutX="298.0" layoutY="67.0" prefWidth="183.0" promptText="Adresse du compteur">
      <items>
        <FXCollections fx:factory="observableArrayList">
          <String fx:value="Item 1" />
          <String fx:value="Item 2" />
        </FXCollections>
      </items>
    </ComboBox>
    <Button fx:id="bt_visualiser" layoutX="357.0" layoutY="105.0" mnemonicParsing="false" onAction="buttonAction" text="Visualiser" />
  </children>
</AnchorPane>

Answer 1

您正在为根本没有上下文的按钮指定一个动作处理程序：

<Button ... onAction="buttonAction" ... />

根据文档，事件处理程序要么被指定为控制器方法（最常见的方式），要么使用脚本语言（很少见）。要使用控制器，您需要指定并实现一个控制器类，并在处理事件的方法名称前加上#. 例如：

package my.package ;

public class MyControllerClass {

    // ...

    @FXML
    private void buttonAction() {
        // code to execute when button is fired
    }
}

然后在 FXML 中执行：

<Button ... onAction="buttonAction" ... />

如果 for 属性onAction不以 开头#，则将其解释为脚本代码。这是一种不太常见的处理事件的方法。为此，您必须language在 FXML 序言中有一个指令，并且该onAction属性的内容必须是有效的脚本代码：

package my.package ;

public class MyControllerClass {

    // ...

    @FXML
    private void buttonAction() {
        // code to execute when button is fired
    }
}

（并且您可以在<script>标签中定义函数，可以从此属性引用等。再次，请参阅文档。）

在您的代码中，由于该onAction属性没有开始#，FXML 解析器需要脚本代码，但由于您没有language指令，它无法尝试解释它；因此例外。