我正在尝试使用FXML和Scene Builder创建我的第一个JavaFX程序。 因此一切正常，直到我尝试扩展Canvas并创建自定义画布为止。
我的代码：
package View;
import javafx.scene.canvas.Canvas;
import javafx.scene.canvas.GraphicsContext;
public class mazeDisplayer extends Canvas {
int[][] mazeData;
public void setMazeData(int[][] mazeData) {
this.mazeData = mazeData;
}
public void redraw() {
if(mazeData != null) {
double W = getWidth();
double H = getHeight();
double w = W/mazeData[0].length;
double h = H/mazeData.length;
GraphicsContext gc = getGraphicsContext2D();
for(int i=0;i<mazeData.length;i++)
for(int j=0;j<mazeData[i].length;j++) {
if(mazeData[i][j]!=0) {
gc.fillRect(w*j,h*i,w,h);
}
}
}
}
}
在我的主视图上，这是我的代码：
public class MainWindowController implements Observer {
ViewModel vm;
@FXML
Pane manualPane,autoPilotPane,homePane;
@FXML
TextArea textArea;
@FXML
TextField ipTextX,portTextY;
@FXML
Circle smallCircle,bigCircle;
@FXML
Slider rudderSlider,throttleSlider;
@FXML
mazeDisplayer mazeDisplayer;
DoubleProperty aileron,elevator;
public MainWindowController() {
aileron = new SimpleDoubleProperty();
elevator = new SimpleDoubleProperty();
}
public void setViewModel(ViewModel vm) {
this.vm = vm;
vm.ipText.bind(ipTextX.textProperty());
vm.portText.bind(portTextY.textProperty());
vm.textAreaAutoPilot.bind(textArea.textProperty());
vm.throttle.bind(throttleSlider.valueProperty());
vm.rudder.bind(rudderSlider.valueProperty());
vm.aileron.bind(aileron);
vm.elevator.bind(elevator);
}
public void draw() {
mazeDisplayer.setMazeData(vm.drawCanvas());
mazeDisplayer.redraw();
}
public void moveJoystick() {
smallCircle.setOnMouseDragged((MouseEvent e)-> {
if(e.getX() < (bigCircle.getRadius() - smallCircle.getRadius())
&& e.getX() > -(bigCircle.getRadius() - smallCircle.getRadius())
&& e.getY() < (bigCircle.getRadius() - smallCircle.getRadius())
&& e.getY() > -(bigCircle.getRadius() - smallCircle.getRadius()))
{
smallCircle.setCenterX(e.getX());
smallCircle.setCenterY(e.getY());
aileron.set(e.getX()/bigCircle.getRadius());
elevator.set(e.getY()/bigCircle.getRadius());
vm.moveAileron();
vm.moveElevator();
}
});
smallCircle.setOnMouseReleased((MouseEvent e)->{
smallCircle.setCenterX(0);
smallCircle.setCenterY(0);
});
}
public void moveThrottleSlider() {
vm.moveThrottle();
}
public void moveRudderSlider() {
vm.moveRudder();
}
public void onConnect() {
vm.connect();
}
public void displayHomePane() {
autoPilotPane.setVisible(false);
manualPane.setVisible(false);
homePane.setVisible(true);
}
public void displayManualPane() {
autoPilotPane.setVisible(false);
homePane.setVisible(false);
manualPane.setVisible(true);
}
public void displayAutoPilotlPane() {
homePane.setVisible(false);
manualPane.setVisible(false);
autoPilotPane.setVisible(true);
}
public void loadScriptDATA() {
FileChooser fc = new FileChooser();
fc.setTitle("open CSV file");
fc.setInitialDirectory(new File("./resources"));
File chosen = fc.showOpenDialog(null);
//showText(chosen);
}
public void loadScriptAutoPilot() {
FileChooser fc = new FileChooser();
fc.setTitle("open CSV/text file");
fc.setInitialDirectory(new File("./resources"));
File chosen = fc.showOpenDialog(null);
showText(chosen);
// chosen.renameTo(new File("cmd.txt"));
}
public void onStartAutoPilot() {
vm.startAutoPilot();
}
public void showText(File choose) {
textArea.setWrapText(true);
try (Scanner s = new Scanner(choose)) {
while(s.hasNextLine()) {
textArea.appendText(s.nextLine()+"\n");
}
} catch (FileNotFoundException e) {e.printStackTrace();}
}
/**
* This method is called whenever the observed object is changed. An
* application calls an <tt>Observable</tt> object's
* <code>notifyObservers</code> method to have all the object's
* observers notified of the change.
*
* @param o the observable object.
* @param arg an argument passed to the <code>notifyObservers</code>
*/
@Override
public void update(Observable o, Object arg) {
}
}
这使我的程序抛出异常，我在此附加这些异常。 希望有人能知道为什么我不能制作自定义Canvas并正确运行它。
"C:\Program Files\Java\jdk1.8.0_211\bin\java.exe" "-javaagent:C:\Program Files\JetBrains\IntelliJ IDEA 2019.1.3\lib\idea_rt.jar=53689:C:\Program Files\JetBrains\IntelliJ IDEA 2019.1.3\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.8.0_211\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_211\jre\lib\rt.jar;C:\projectIntel\mile_stone_5-master\out\production\mile_stone_5;C:\projectIntel\mile_stone_5-master\out\production\my_mile_stone_4" View.Main
Exception in Application start method
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:498)
at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:389)
at com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:328)
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:498)
at sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:767)
Caused by: java.lang.RuntimeException: Exception in Application start method
at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:917)
at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$159(LauncherImpl.java:182)
at java.lang.Thread.run(Thread.java:748)
Caused by: javafx.fxml.LoadException:
unknown path
at javafx.fxml.FXMLLoader.constructLoadException(FXMLLoader.java:2601)
at javafx.fxml.FXMLLoader.importClass(FXMLLoader.java:2848)
at javafx.fxml.FXMLLoader.processImport(FXMLLoader.java:2692)
at javafx.fxml.FXMLLoader.processProcessingInstruction(FXMLLoader.java:2661)
at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2517)
at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2425)
at View.Main.start(Main.java:16)
at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$166(LauncherImpl.java:863)
at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$179(PlatformImpl.java:326)
at com.sun.javafx.application.PlatformImpl.lambda$null$177(PlatformImpl.java:295)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.application.PlatformImpl.lambda$runLater$178(PlatformImpl.java:294)
at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$152(WinApplication.java:177)
... 1 more
Caused by: java.lang.ClassNotFoundException
at javafx.fxml.FXMLLoader.loadType(FXMLLoader.java:2899)
at javafx.fxml.FXMLLoader.importClass(FXMLLoader.java:2846)
... 14 more
Exception running application View.Main
Process finished with exit code 1
这是我在fxml文件中创建带有ID的自定义Canvas的行：
<mazeDisplayer fx:id="mazeDisplayer" height="300" width="300" BorderPane.alignment="CENTER" />
主应用程序中的异常：
Parent root = fxl.load(getClass().getResource("sample.fxml").openStream());