在Controller中处理/更改FXML中的元素

时间：2017-11-13 02:53:28

标签： java javafx fxml scenebuilder fxmlloader

第一次问这里，我对使用SceneBuilder的javafx和FXML很新。我正在尝试将标签的文本更改为用户在按下按钮时在文本字段中输入的内容，但是我收到错误。当我将按钮的“on-action-method”设置为仅打印一些随机单词时，它可以正常工作。

主：

public class Controller {

    @FXML private TextField critTF;
    @FXML private Label label4;

    @FXML
    private void calculateButtonClicked (ActionEvent event){

        label4.setText(critTF.getText());
    }   
}

控制器：

<AnchorPane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="476.0" prefWidth="376.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="sample.Controller">
   <children>
      <GridPane layoutX="44.0" layoutY="138.0" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="25.0">
        <columnConstraints>
          <ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
          <ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
        </columnConstraints>
        <rowConstraints>
          <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
          <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
          <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
            <RowConstraints maxHeight="85.0" minHeight="10.0" prefHeight="38.0" vgrow="SOMETIMES" />
            <RowConstraints maxHeight="160.0" minHeight="10.0" prefHeight="142.0" vgrow="SOMETIMES" />
        </rowConstraints>
         <children>
            <Label text="Haste">
               <padding>
                  <Insets bottom="20.0" left="20.0" right="20.0" top="20.0" />
               </padding>
            </Label>
            <Label text="Critical Strike" GridPane.rowIndex="1">
               <GridPane.margin>
                  <Insets bottom="20.0" left="20.0" right="20.0" top="20.0" />
               </GridPane.margin>
            </Label>
            <Label text="Mastery" GridPane.rowIndex="2">
               <GridPane.margin>
                  <Insets bottom="20.0" left="20.0" right="20.0" top="20.0" />
               </GridPane.margin>
            </Label>
            <Label text="Versatility" GridPane.rowIndex="3">
               <GridPane.margin>
                  <Insets bottom="20.0" left="20.0" right="20.0" top="20.0" />
               </GridPane.margin>
            </Label>
            <TextField id="hasteTF" GridPane.columnIndex="1">
               <GridPane.margin>
                  <Insets right="20.0" />
               </GridPane.margin>
            </TextField>
            <TextField id="critTF" GridPane.columnIndex="1" GridPane.rowIndex="1">
               <GridPane.margin>
                  <Insets right="20.0" />
               </GridPane.margin>
            </TextField>
            <TextField id="masteryTF" GridPane.columnIndex="1" GridPane.rowIndex="2">
               <GridPane.margin>
                  <Insets right="20.0" />
               </GridPane.margin>
            </TextField>
            <TextField id="versaTF" GridPane.columnIndex="1" GridPane.rowIndex="3">
               <GridPane.margin>
                  <Insets right="20.0" />
               </GridPane.margin>
            </TextField>
            <Button mnemonicParsing="false" onAction="#calculateButtonClicked" prefHeight="81.0" prefWidth="151.0" text="Calculate" GridPane.rowIndex="4">
               <GridPane.margin>
                  <Insets bottom="20.0" left="20.0" right="20.0" top="20.0" />
               </GridPane.margin>
            </Button>
            <GridPane GridPane.columnIndex="1" GridPane.rowIndex="4">
              <columnConstraints>
                <ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
                <ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
              </columnConstraints>
              <rowConstraints>
                <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
                <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
                <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
              </rowConstraints>
               <children>
                  <Label text="Label" />
                  <Label text="Label" GridPane.rowIndex="1" />
                  <Label text="Label" GridPane.rowIndex="2" />
                  <Label id="label4" text="Label" GridPane.columnIndex="1" />
                  <Label text="Label" GridPane.columnIndex="1" GridPane.rowIndex="1" />
                  <Label text="Label" GridPane.columnIndex="1" GridPane.rowIndex="2" />
               </children>
            </GridPane>
         </children>
      </GridPane>
      <MenuBar layoutX="82.0" layoutY="2.0" prefHeight="25.0" prefWidth="128.0" AnchorPane.bottomAnchor="451.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="0.0">
        <menus>
          <Menu mnemonicParsing="false" text="About">
            <items>
              <MenuItem mnemonicParsing="false" text="Close" />
            </items>
          </Menu>
        </menus>
      </MenuBar>
   </children>
</AnchorPane>

fx：在FXML文件中将id设置为critTF和label4，并将fx：controller设置为根元素上的sample.Controller，这是正确的路径。

任何帮助表示感谢，谢谢！

修改

FXML：

Exception in thread "JavaFX Application Thread" java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1774)
at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(FXMLLoader.java:1657)
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.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:8413)
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.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$MouseHandler.process(Scene.java:3757)
at javafx.scene.Scene$MouseHandler.access$1500(Scene.java:3485)
at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1762)
at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2494)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:381)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:295)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEvent$354(GlassViewEventHandler.java:417)
at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:389)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:416)
at com.sun.glass.ui.View.handleMouseEvent(View.java:555)
at com.sun.glass.ui.View.notifyMouse(View.java:937)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$148(WinApplication.java:191)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at sun.reflect.misc.Trampoline.invoke(Unknown Source)
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at sun.reflect.misc.MethodUtil.invoke(Unknown Source)
at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1769)
... 48 more
Caused by: java.lang.NullPointerException
at sample.Controller.calculateButtonClicked(Controller.java:21)
... 58 more

WO1

0 个答案:

没有答案
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