Javafx：单击按钮时更改 Imageview 中的图像

Question

控制器类：

import com.jfoenix.controls.JFXButton;
import javafx.fxml.FXML;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;

public class ControllerBuildingPlans {
    @FXML public ImageView imgView;
    @FXML public JFXButton bldingBtn1;
    @FXML public JFXButton bldingBtn2;

    @FXML public void bldingBtnClick1() {
        imgView.setImage(new Image("com/application/Menu/viewBuildingPlans/building1 plan.jpg"));
    }

    @FXML
    public void bldingBtnClick2() {
        imgView.setImage(new Image("com/application/Menu/viewBuildingPlans/building2 plan.jpg"));
    }
}

fxml 类：

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

<?import com.jfoenix.controls.JFXButton?>
<?import javafx.geometry.Insets?>
<?import javafx.scene.control.Hyperlink?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.image.Image?>
<?import javafx.scene.image.ImageView?>
<?import javafx.scene.layout.AnchorPane?>
<?import javafx.scene.layout.HBox?>
<?import javafx.scene.text.Font?>
<?import javafx.scene.text.TextFlow?>

<AnchorPane prefHeight="502.0" prefWidth="682.0" style="-fx-background-color: #2D3447;" xmlns="http://javafx.com/javafx/8.0.141" xmlns:fx="http://javafx.com/fxml/1" fx:controller="com.application.Menu.viewBuildingPlans.ControllerBuildingPlans">
    <children>
      <HBox alignment="CENTER_RIGHT" layoutX="-1.0" layoutY="4.0" nodeOrientation="LEFT_TO_RIGHT" prefHeight="135.0" prefWidth="682.0">
         <children>
            <AnchorPane prefHeight="135.0" prefWidth="551.0">
               <children>
                  <TextFlow fx:id="Logout" layoutX="7.0" layoutY="7.0" prefHeight="120.0" prefWidth="165.0">
                     <children>
                        <Hyperlink fx:id="lgout" prefHeight="36.0" prefWidth="67.0" text="Logout">
                           <font>
                              <Font size="16.0" />
                           </font>
                        </Hyperlink>
                     </children>
                     <padding>
                        <Insets left="-5.0" />
                     </padding>
                  </TextFlow>
                  <Label layoutX="265.0" layoutY="14.0" prefHeight="57.0" prefWidth="211.0" text="UGNiP Staff System" textAlignment="CENTER" textFill="WHITE">
                     <font>
                        <Font size="24.0" />
                     </font>
                  </Label>
                  <Label alignment="CENTER" contentDisplay="CENTER" layoutX="301.0" layoutY="90.0" prefHeight="57.0" prefWidth="139.0" text="Building Plans" textFill="#f5f5f5">
                     <font>
                        <Font size="21.0" />
                     </font>
                  </Label>
               </children>
               <padding>
                  <Insets left="310.0" right="-233.0" />
               </padding>
            </AnchorPane>
            <AnchorPane prefHeight="200.0" prefWidth="200.0">
               <children>
                    <ImageView fitHeight="120.0" fitWidth="211.0" layoutX="-23.0" layoutY="8.0" nodeOrientation="INHERIT" opacity="0.8" pickOnBounds="true" preserveRatio="true">
                        <image>
                            <Image url="file:/C:/Users/muizu/Documents/codes/cwk3/src/Icons/image.jpeg" />
                        </image>
                    </ImageView>
               </children>
            </AnchorPane>
         </children>
      </HBox>
        <JFXButton fx:id="bldingBtn1" layoutX="610.0" layoutY="185.0" prefHeight="47.0" prefWidth="118.0" style="-fx-background-color: #3C5BFA;" text="Building 1" textFill="#f5f5f5">
            <font>
                <Font size="18.0" />
            </font>
        </JFXButton>
      <JFXButton fx:id="bldingBtn2" layoutX="610.0" layoutY="310.0" onAction="#bldingBtnClick2" prefHeight="47.0" prefWidth="118.0" style="-fx-background-color: #3C5BFA;" text="Building 2" textFill="#f5f5f5">
         <font>
            <Font size="18.0" />
         </font>
      </JFXButton>
      <JFXButton fx:id="Back" layoutY="404.0" prefHeight="47.0" prefWidth="86.0" style="-fx-background-color: #3C5BFA;" text="Back" textFill="#f5f5f5">
         <font>
            <Font size="18.0" />
         </font>
      </JFXButton>
      <ImageView fx:id="imgViewer" fitHeight="313.0" fitWidth="483.0" layoutX="118.0" layoutY="150.0" pickOnBounds="true" preserveRatio="true" />
    </children>
</AnchorPane>

错误信息：

线程“JavaFX 应用程序线程”中的异常 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) 在 com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86) 在 com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238) 在 com.sun.javafx。 event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191) 在 com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59) 在 com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Basic:javaEvent8DispatchEvent)在 com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) 在 com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56) 在 com.sun.javafx. t(EventDispatchChainImpl.java:114) at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56) at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:11s) .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) 在 com.sun.javafx.scene.control.skin.BehaviorSkinBase$1.handle(BehaviorSkinBase.java:96) 在 com.sun.javafx.scene.control.skin.BehaviorSkinBase$1.handle(BehaviorSkinBase.java: 89) 在 com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(CompositeEventHandler.java:218) 在 com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:80) 在 com.su n.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238) 在 com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191) 在 com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(Composite. java:59) 在 com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58) 在 com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) 在 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.dispatch6) at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) 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) 在 javafx.event.Event.fireEvent(E vent.java:198) 在 javafx.scene.Scene$MouseHandler.process(Scene.java:3757) 在 javafx.scene.Scene$MouseHandler.access$1500(Scene.java:3485) 在 javafx.scene.Scene.impl_processMouseEvent( Scene.java:1762) at javafx.scene.Scene$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) 在 java.security.AccessController.doPrivileged(Native Method) 在 com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEventView$354(GlassViewEventView$354(GlassEventHandler) .java:417) 在 com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:389) 在 com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:416) 在 com。 sun.glass.ui.View.handleMouseEvent(View.java:555) at com.sun.glass.ui.View.notifyMouse(View.java:937) at com.sun.glass.ui.win.WinApplication。 _runLoop(Native Method) at com.sun.glass.ui.win.WinApplication.lambda$null$148(WinApplication.java:191) at java.lang.Thread.run(Thread.java:748) 由：java.lang .reflect.InvocationTargetException at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java.java:43) .reflect.Method.invoke(Method.java:498) at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71) at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke (DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275) at javafx.fxml.FXMLLoader$MethodHandler。 invoke(FXMLLoader.java:1771) ... 48 more 引起：java.lang.NullPointerException at com.application.Menu.viewBuildingPlans.ControllerBuildingPlans.bldin gBtnClick2(ControllerBuildingPlans.java:16) ... 58 更多

我希望能够在单击每个按钮时更改图像。

Answer 1

在fx:id=imageViewer应改为fx:id=imgView在类的字段名称，也同样为所有fx:id在它们应与在类的字段名的FXML。

Answer 2

您在 fxml 文件中为 ImageView 设置了错误的 id。 在 fxml 和 java 文件中都应该是 Imgview 或 Imgviewer