我正在尝试使用
JavaFX制作屏幕录像机.我正在谷歌搜索如何制作一个,当我看到
this文章,我尝试了它并且非常喜欢它,所以我决定用它提供的代码制作一个JavaFX FXML应用程序.
@FXML
void startOnAction(ActionEvent event) {
FXMLDocumentController FXML = new FXMLDocumentController();
FXML.console.setText("######### Starting Screen Recorder #########");
try {
Thread.sleep(250);
} catch (InterruptedException ex) {
}
Dimension screen = Toolkit.getDefaultToolkit().getScreenSize();
FXML.console.appendText("Your Screen [Width, Height]: " + "[" + screen.getWidth() + "," + screen.getHeight() + "]\nWhen the Recording starts, this window will minimize, to stop them recording, open this window.");
try {
Thread.sleep(1000);
} catch (InterruptedException ex) {
}
FXML.console.appendText("The recording will start in 5 seconds");
int num = 5;
for (int i = 0; i <= 5; i++) {
System.out.print(num);
try {
Thread.sleep(1000);
} catch (InterruptedException ex) {
}
num = num - 1;
}
FXML.console.appendText("Start!");
File f = new File(store);
if (!f.exists()) {
f.mkdir();
}
startRecord();
Recorder R = new Recorder();
R.stage.setIconified(true);
R.stage.focusedProperty().addListener((ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean newValue) -> {
focusState(newValue);
});
}
这是FXMLDocumentController中的一个方法,我想让我的TextArea变量’console’打印出我希望它打印出来的文本.
但是,我使用的所有行都使用了一个对象,这些FXMLDocumentController FXML = new FXMLDocumentController();和记录器R = new Recorder();
有一个错误.
这是错误：
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$MouseEventNotification.run(GlassViewEventHandler.java:380)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:294)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEvent$354(GlassViewEventHandler.java:416)
at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:389)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:415)
at com.sun.glass.ui.View.handleMouseEvent(View.java:555)
at com.sun.glass.ui.View.notifyMouse(View.java:937)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$148(WinApplication.java:191)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)
at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1769)
... 48 more
Caused by: java.lang.NullPointerException
at recorder.FXMLDocumentController.startOnAction(FXMLDocumentController.java:127)
... 58 more
Line 127 is `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$MouseEventNotification.run(GlassViewEventHandler.java:380)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:294)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEvent$354(GlassViewEventHandler.java:416)
at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:389)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:415)
at com.sun.glass.ui.View.handleMouseEvent(View.java:555)
at com.sun.glass.ui.View.notifyMouse(View.java:937)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$148(WinApplication.java:191)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)
at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1769)
... 48 more
Caused by: java.lang.NullPointerException
at recorder.FXMLDocumentController.startOnAction(FXMLDocumentController.java:127)
... 58 more`
第127行是第4行,在我上面发布的代码中.
完整代码如下……
主要课程：
package recorder;
import javafx.application.Application;
import static javafx.application.Application.launch;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;
public class Recorder extends Application {
public Stage stage;
@Override
public void start(Stage stage) throws Exception {
Parent root = FXMLLoader.load(getClass().getResource("FXMLDocument.fxml"));
Scene scene = new Scene(root);
stage.setResizable(false);
stage.setScene(scene);
stage.show();
}
public static void main(String[] args) {
launch(args);
}
}
FXML文件：
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.control.Button?>
<?import javafx.scene.control.TextArea?>
<?import javafx.scene.control.TextField?>
<?import javafx.scene.layout.ColumnConstraints?>
<?import javafx.scene.layout.GridPane?>
<?import javafx.scene.layout.RowConstraints?>
<GridPane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="639.0" prefWidth="578.0" xmlns="http://javafx.com/javafx/8.0.60" xmlns:fx="http://javafx.com/fxml/1" fx:controller="recorder.FXMLDocumentController">
<columnConstraints>
<ColumnConstraints hgrow="SOMETIMES" minWidth="578.0" prefWidth="578.0" />
</columnConstraints>
<rowConstraints>
<RowConstraints maxHeight="1.7976931348623157E308" minHeight="10.0" prefHeight="95.0" vgrow="SOMETIMES" />
<RowConstraints maxHeight="245.0" minHeight="9.0" prefHeight="12.0" vgrow="SOMETIMES" />
<RowConstraints maxHeight="481.0" minHeight="10.0" prefHeight="478.0" vgrow="SOMETIMES" />
</rowConstraints>
<children>
<Button fx:id="start" maxHeight="1.7976931348623157E308" maxWidth="1.7976931348623157E308" mnemonicParsing="false" onAction="#startOnAction" prefHeight="220.0" prefWidth="578.0" text="Start Recording" />
<TextArea fx:id="console" editable="false" prefHeight="200.0" prefWidth="200.0" promptText="Console" wrapText="true" GridPane.rowIndex="2" />
<TextField fx:id="input" prefHeight="105.0" prefWidth="578.0" promptText="File Name" GridPane.rowIndex="1" />
</children>
</GridPane>
FXMLDocumentController(代码片段来自)：
package recorder;
import java.awt.Dimension;
import java.awt.Rectangle;
import java.awt.Robot;
import java.awt.Toolkit;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.OutputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ResourceBundle;
import java.util.Vector;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.beans.value.ObservableValue;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Button;
import javafx.scene.control.TextArea;
import javafx.scene.control.TextField;
import javax.imageio.ImageIO;
import javax.media.MediaLocator;
import javax.swing.JOptionPane;
public class FXMLDocumentController implements Initializable {
File file;
/**
* Screen Width.
*/
public static int screenWidth = (int) Toolkit.getDefaultToolkit()
.getScreenSize().getWidth();
/**
* Screen Height.
*/
public static int screenHeight = (int) Toolkit.getDefaultToolkit()
.getScreenSize().getHeight();
/**
* Interval between which the image needs to be captured.
*/
public static int captureInterval = 50;
/**
* Temporary folder to store the screenshot.
*/
public static String store = "tmp";
/**
* Status of the recorder.
*/
public static boolean record = false;
@FXML
private Button start;
@FXML
private TextArea console;
@FXML
private TextField input;
public static void startRecord() {
Thread recordThread = new Thread() {
@Override
public void run() {
Robot rt;
int cnt = 0;
try {
rt = new Robot();
while (cnt == 0 || record) {
BufferedImage img = rt.createScreenCapture(new Rectangle(screenWidth, screenHeight));
ImageIO.write(img, "jpeg", new File("./" + store + "/"
+ System.currentTimeMillis() + ".jpeg"));
if (cnt == 0) {
record = true;
cnt = 1;
}
Thread.sleep(captureInterval);
}
} catch (Exception e) {
e.printStackTrace();
}
}
};
recordThread.start();
}
/**
* @throws MalformedURLException
*
*/
public static void makeVideo(String movFile) throws MalformedURLException {
FXMLDocumentController FXML = new FXMLDocumentController();
FXML.console.appendText("Processing Video... please wait");
JpegImagesToMovie imageToMovie = new JpegImagesToMovie();
Vector<String> imgLst = new Vector<String>();
File f = new File(store);
File[] fileLst = f.listFiles();
for (int i = 0; i < fileLst.length; i++) {
imgLst.add(fileLst[i].getAbsolutePath());
}
// Generate the output media locators.
MediaLocator oml;
if ((oml = imageToMovie.createMediaLocator(movFile)) == null) {
FXML.console.appendText("Error in processing");
System.exit(0);
}
imageToMovie.doIt(screenWidth, screenHeight, (1000 / captureInterval), imgLst, oml);
}
@FXML
void setOnAction(ActionEvent event) {
String path = JOptionPane.showInputDialog("Type in the File Path", "C:/Users/" + System.getProperty("user.name") + "/Desktop");
file = new File(path);
}
@FXML
void startOnAction(ActionEvent event) {
FXMLDocumentController FXML = new FXMLDocumentController();
FXML.console.setText("######### Starting Screen Recorder #########");
try {
Thread.sleep(250);
} catch (InterruptedException ex) {
}
Dimension screen = Toolkit.getDefaultToolkit().getScreenSize();
FXML.console.appendText("Your Screen [Width, Height]: " + "[" + screen.getWidth() + "," + screen.getHeight() + "]\nWhen the Recording starts, this window will minimize, to stop them recording, open this window.");
try {
Thread.sleep(1000);
} catch (InterruptedException ex) {
}
FXML.console.appendText("The recording will start in 5 seconds");
int num = 5;
for (int i = 0; i <= 5; i++) {
System.out.print(num);
try {
Thread.sleep(1000);
} catch (InterruptedException ex) {
}
num = num - 1;
}
FXML.console.appendText("Start!");
File f = new File(store);
if (!f.exists()) {
f.mkdir();
}
startRecord();
Recorder R = new Recorder();
R.stage.setIconified(true);
R.stage.focusedProperty().addListener((ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean newValue) -> {
focusState(newValue);
});
}
;
private void focusState(boolean value) {
if (value) {
System.out.println("Focus Gained");
record = false;
try {
makeVideo(input.getText() + ".mov");
} catch (MalformedURLException ex) {
}
} else {
}
}
@Override
public void initialize(URL url, ResourceBundle rb) {
}
}
我希望我正确地遵循了你的指导方针和内容.
最佳答案 您只是创建一个FXMLDocumentController实例,该实例与任何已加载FXMLLoader的fxml无关.
然而,FXMLLoader负责注入字段值,它只会在加载fxml文件时将字段注入FXMLLoader使用的控制器类的实例(即FXMLLoader基于fx：controller属性创建的一个或者一个使用setController提供;在这两种情况下,可以在调用load之后直接使用FXMLLoader.getController检索实例.
从未修改的字段仍包含默认值null,这会导致NPE,例如这里：
FXMLDocumentController FXML = new FXMLDocumentController();
FXML.console.setText("######### Starting Screen Recorder #########");
this.console.setText("######### Starting Screen Recorder #########");
可能会成功,但请注意您使用Thread.sleep阻止代码中的应用程序线程几秒钟,这将使应用程序暂停…
要在添加场景后检索窗口,您可以使用场景内的节点：
Stage stage = (Stage) this.console.getScene().getWindow();
stage.setIconified(true);
stage.focusedProperty()...
