专家!我只是想为这对控制器使用一个按钮,这样我就可以让我的代码变短。在boderpane的底部,我创建了用于更改borderpane中心视图的按钮,一旦点击下一个按钮,它就会改变位于borderpane中心的另一个视图。但是,如果我点击检查按钮,我预计displayMassageLabel的按摩会出现,但它会出错..有没有人来解决这个问题..? 以下是我在下面简单介绍的示例代码。
ChangeControllerTestMain.java
package javafxapplication2;
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;
/**
*
* @author James
*/
public class ChangeControllerTestMain extends Application {
@Override
public void start(Stage stage) throws Exception {
Parent root = FXMLLoader.load(getClass().getResource("Main.fxml"));
Scene scene = new Scene(root);
stage.setScene(scene);
stage.show();
}
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
launch(args);
}
}
Main.fxml
<?xml version="1.0" encoding="UTF-8"?>
<?import java.lang.*?>
<?import java.util.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<BorderPane fx:id="borderPane" maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="javafxapplication2.MainController">
<bottom>
<HBox alignment="CENTER" prefHeight="39.0" prefWidth="600.0" spacing="100.0" BorderPane.alignment="CENTER">
<children>
<Button fx:id="backButton" mnemonicParsing="false" onAction="#handleBackButtonAction" text="<Back" />
<Button fx:id="checkButton" mnemonicParsing="false" onAction="#handleCheckButtonAction" text="Check" />
<Button fx:id="nextButton" mnemonicParsing="false" onAction="#handleNextButtonAction" text="Next>" />
</children></HBox>
</bottom>
</BorderPane>
MainColtroller.java
package javafxapplication2;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.fxml.Initializable;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.layout.AnchorPane;
import javafx.scene.layout.BorderPane;
/**
*
* @author James
*/
public class MainController implements Initializable {
@FXML
private BorderPane borderPane;
private AnchorPane anchorPane;
private Label displayMassageLabel;
@FXML
private Button backButton;
@FXML
private Button checkButton;
@FXML
private Button nextButton;
private int currentMenuNum;
private String currentViewerPath;
private String pathList[] = {"StartDisplay.fxml", "Menu1Display.fxml", "Menu2Display.fxml", "Menu3Display.fxml"};
private Menu1DisplayController menu1DisplayController = new Menu1DisplayController();
private Menu2DisplayController menu2DisplayController = new Menu2DisplayController();
private Menu3DisplayController menu3DisplayController = new Menu3DisplayController();
@Override
public void initialize(URL url, ResourceBundle rb) {
// TODO
currentMenuNum = 0;
currentViewerPath = pathList[currentMenuNum];
System.out.println(currentViewerPath);
setControlItems(currentViewerPath, currentMenuNum);
}
private void setControlItems(String path, int currentMenuNum) {
//Display setting for menu
FXMLLoader fxmlLoader = new FXMLLoader();
try {
fxmlLoader.setLocation(getClass().getResource(path));
anchorPane = fxmlLoader.load();
//connectionViewerController = (ConnectionViewerController) fxmlLoader.getController();
} catch (Exception e) {
System.out.println(e.getStackTrace().toString());
System.out.println(e.getMessage());
}
borderPane.setCenter(anchorPane);
if (currentMenuNum == 1) {
menu1DisplayController = (Menu1DisplayController) fxmlLoader.getController();
} else if (currentMenuNum == 2) {
menu2DisplayController = (Menu2DisplayController) fxmlLoader.getController();
} else if (currentMenuNum == 3) {
menu3DisplayController = (Menu3DisplayController) fxmlLoader.getController();
}
}
private String getCurrentViewerPath(int currentMenuNum) {
currentViewerPath = pathList[currentMenuNum];
return currentViewerPath;
}
@FXML
private void handleBackButtonAction(ActionEvent event) {
if (currentMenuNum == 0) {
return;
}
currentMenuNum = currentMenuNum - 1;
currentViewerPath = getCurrentViewerPath(currentMenuNum);
setControlItems(currentViewerPath, currentMenuNum);
}
@FXML
private void handleNextButtonAction(ActionEvent event) {
currentMenuNum = currentMenuNum + 1;
currentViewerPath = getCurrentViewerPath(currentMenuNum);
setControlItems(currentViewerPath, currentMenuNum);
}
@FXML
private void handleCheckButtonAction(ActionEvent event) {
displayMassageLabel.setText("Welcome Menu " + currentMenuNum);
}
}
StartDisplay.fxml
<?xml version="1.0" encoding="UTF-8"?>
<?import java.lang.*?>
<?import java.util.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<AnchorPane id="AnchorPane" prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1">
<children>
<VBox alignment="CENTER" layoutX="10.0" layoutY="10.0" prefHeight="361.0" prefWidth="600.0" spacing="20.0">
<children>
<Label text="Display Message" />
<Label text="Start Display" />
<Label fx:id="displayMassageLabel" />
</children>
</VBox>
</children>
</AnchorPane>
Menu1DisplayController.java
package javafxapplication2;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Label;
/**
* FXML Controller class
*
* @author James
*/
public class Menu1DisplayController implements Initializable {
@FXML
private Label displayMassageLabel;
/**
* Initializes the controller class.
*/
@Override
public void initialize(URL url, ResourceBundle rb) {
// TODO
}
@FXML
private void handleCheckButtonAction(ActionEvent event) {
displayMassageLabel.setText("Welcome Menu 1");
}
}
Menu1Display.fxml
<?xml version="1.0" encoding="UTF-8"?>
<?import java.lang.*?>
<?import java.util.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<AnchorPane id="AnchorPane" prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="javafxapplication2.Menu1DisplayController">
<children>
<VBox alignment="CENTER" layoutX="10.0" layoutY="10.0" prefHeight="361.0" prefWidth="600.0" spacing="20.0">
<children>
<Label text="Display Message" />
<Label text="Current Menu is 1" />
<Label fx:id="displayMassageLabel" />
</children>
</VBox>
</children>
</AnchorPane>
menu2和3的FXML文件和控制器与菜单1相同。 请求帮助我。
这些是错误..
Exception in thread "JavaFX Application Thread" java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1770)
at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(FXMLLoader.java:1653)
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:8390)
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$MouseHandler.process(Scene.java:3758)
at javafx.scene.Scene$MouseHandler.access$1500(Scene.java:3486)
at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1762)
at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2495)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:350)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:275)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEvent$350(GlassViewEventHandler.java:385)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$$Lambda$105/472212858.get(Unknown Source)
at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:404)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:384)
at com.sun.glass.ui.View.handleMouseEvent(View.java:555)
at com.sun.glass.ui.View.notifyMouse(View.java:927)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$145(WinApplication.java:101)
at com.sun.glass.ui.win.WinApplication$$Lambda$36/1963387170.run(Unknown Source)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)
at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1765)
... 50 more
Caused by: java.lang.NullPointerException
at javafxapplication2.MainController.handleCheckButtonAction(MainController.java:101)
... 60 more
答案 0 :(得分:0)
添加功能
public void setDisplayMessageLabel(String message){
displayMassageLabel.setText(message);
}
到所有Menu1DisplayControllers(Menu1,Menu2,...)。 知道你可以从你的MainContorller中调用这个函数,如
@FXML
private void handleCheckButtonAction(ActionEvent event) {
if (currentMenuNum == 1) {
menu1DisplayController.setDisplayMassageLabel("Welcome Menu " + currentMenuNum;
} else if (currentMenuNum == 2) {
menu2DisplayController.setDisplayMassageLabel("Welcome Menu " + currentMenuNum;
} else if (currentMenuNum == 3) {
menu3DisplayController.setDisplayMassageLabel("Welcome Menu " + currentMenuNum;
}
}