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Enter key code for Java key event handlers

I am writing a code for a simple web browser for my school project. Currently I want to have the code to be able to visit the site entered in the url when pressed the enter key. All of my buttons work (back, forward, refresh, etc) but I cant seem to get the keyboard event handlers working.
The error that I am currently faced with in the event handler is that its not getting the code for the enter key. I already looked at many different sources like this one Trying to get the char code of ENTER key but they havent been much help to solve my issue.
Here is the code I'm working on:
package application;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.application.Application;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TextField;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.text.Text;
import javafx.scene.web.WebEngine;
import javafx.scene.web.WebHistory;
import javafx.scene.web.WebView;
public class Main extends Application {
private BorderPane root;
private WebView webView;
private WebEngine webEngine;
private HBox addressBar;
private HBox statusBar;
private Text domain;
private WebHistory history;
private final String homePage = "https://google.ca";
//------------------------------------------------------
private void setupAddressBar() {
addressBar = new HBox();
Button home = new Button("Home");
Button back = new Button("<--");
Button forward = new Button("-->");
Button refresh = new Button("Refresh");
TextField url = new TextField();
addressBar.getChildren().addAll(home,back,forward,refresh,url);
class HomeButton implements EventHandler<ActionEvent>{
#Override
public void handle(ActionEvent e) {
homePage();
}
}
class BackButton implements EventHandler<ActionEvent>{
#Override
public void handle(ActionEvent e) {
back();
}
}
class ForwardButton implements EventHandler<ActionEvent>{
#Override
public void handle(ActionEvent e) {
forward();
}
}
class RefreshButton implements EventHandler<ActionEvent>{
#Override
public void handle(ActionEvent e) {
refreshPage();
}
}
class KeyboardPressedHandler implements EventHandler<KeyEvent>{
#Override
public void handle(KeyEvent event) {
KeyCode key = event.getCode();
if(key == Keycode.ENTER ) {
loadPage();
}
}
}
HomeButton homeButton = new HomeButton();
home.setOnAction(homeButton);
BackButton backButton = new BackButton();
back.setOnAction(backButton);
ForwardButton forwardButton = new ForwardButton();
forward.setOnAction(forwardButton);
RefreshButton refreshButton = new RefreshButton();
refresh.setOnAction(refreshButton);
KeyboardPressedHandler pressedHandler = new KeyboardPressedHandler();
url.setOnKeyReleased(pressedHandler);
}
//----------------------------------------------------
private void setupStatusBar() {
statusBar = new HBox();
domain = new Text("google.ca");
Text separator = new Text("|");
Text copyright = new Text("JavaFX -- All Rights Reserved.");
statusBar.getChildren().addAll(domain, separator, copyright);
}
//-------------------------------------------------
public void setupWebView() {
webView = new WebView();
webEngine = webView.getEngine();
webEngine.load(homePage);
}
public void initialize(URL arg0, ResourceBundle arg1) {
webEngine = webView.getEngine();
loadPage();
}
public void loadPage() {
webEngine.load("http://" + domain.getText());
}
public void homePage() {
webEngine.load("http://google.ca");
}
public void refreshPage() {
webEngine.reload();
}
public void forward() {
history = webEngine.getHistory();
ObservableList<WebHistory.Entry> entries = history.getEntries();
history.go(1);
domain.setText(entries.get(history.getCurrentIndex()).getUrl());
}
public void back() {
history = webEngine.getHistory();
ObservableList<WebHistory.Entry> entries = history.getEntries();
history.go(-1);
domain.setText(entries.get(history.getCurrentIndex()).getUrl());
}
public void start(Stage stage) {
root = new BorderPane();
//---------------------------------
this.setupAddressBar();
this.setupWebView();
this.setupStatusBar();
//----------------------------------
root.setTop(addressBar);
root.setBottom(statusBar);
root.setCenter(webView);
//----------------------------------
Scene scene = new Scene(root);
stage.setScene(scene);
//stage.getFullScreen(true);
stage.setWidth(1200);
stage.setHeight(1000);
stage.setResizable(false);
stage.setTitle("JavaFX Browser");
stage.show();
;
}
public static void main(String[] args) {
launch(args);
}
}

JavaFX Simple Update Label (Threading)

I'm trying to demonstrate to a few beginner programmers how to set a label on a JavaFX app to auto update. Basically they would like the value to decrease every minute or so on the label without any user interaction.
Java isn't my strong point and looking through some previous questions I get that I need to deal with threads and Runnable().
I have put the code together below that works, but I was just wondering if there is a better way of doing this or an easier way to demonstrate the same outcome with simpler code.
public class MainTimer2 extends Application {
private int count = 100;
private Label response = new Label(Integer.toString(count));
public static void main(String[] args) {
launch(args);
}
//Update function
private void decrementCount() {
count--;
response.setText(Integer.toString(count));
}
#Override
public void start(Stage myStage) {
myStage.setTitle("Update Demo");
//Vertical and horizontal gaps set to 10px
FlowPane rootNode = new FlowPane(10, 10);
rootNode.setAlignment(Pos.CENTER);
Scene myScene = new Scene(rootNode, 200, 100);
myStage.setScene(myScene);
Thread thread = new Thread(new Runnable() {
#Override
public void run() {
Runnable updater = new Runnable() {
#Override
public void run() {
decrementCount();
}
};
while (true) {
try {
Thread.sleep(1000);
} catch (InterruptedException ex) {
System.out.println("Timer error");
}
// UI update is run on the Application thread
Platform.runLater(updater);
}
}
});
// don't let thread prevent JVM shutdown
thread.setDaemon(true);
thread.start();
rootNode.getChildren().addAll(response);
myStage.show();
}
}

Count down by using PauseTransition:
import javafx.animation.PauseTransition;
import javafx.application.Application;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.layout.FlowPane;
import javafx.stage.Stage;
import javafx.util.Duration;
public class MainTimer2 extends Application {
private int count = 100;
private Label response = new Label(Integer.toString(count));
public static void main(String[] args) {
launch(args);
}
#Override
public void start(Stage myStage) {
myStage.setTitle("Update Demo");
//Vertical and horizontal gaps set to 10px
FlowPane rootNode = new FlowPane(10, 10);
rootNode.setAlignment(Pos.CENTER);
Scene myScene = new Scene(rootNode, 200, 100);
myStage.setScene(myScene);
rootNode.getChildren().addAll(response);
myStage.show();
update();
}
private void update() {
PauseTransition pause = new PauseTransition(Duration.seconds(1));
pause.setOnFinished(event ->{
decrementCount();
pause.play();
});
pause.play();
}
//Update function
private void decrementCount() {
count = (count > 0) ? count -1 : 100;
response.setText(Integer.toString(count));
}
}
Alternatively you could use Timeline:
private void update() {
KeyFrame keyFrame = new KeyFrame(
Duration.seconds(1),
event -> {
decrementCount();
}
);
Timeline timeline = new Timeline();
timeline.setCycleCount(Animation.INDEFINITE);
//if you want to limit the number of cycles use
//timeline.setCycleCount(100);
timeline.getKeyFrames().add(keyFrame);
timeline.play();
}

Running a thread by toggling a flag externally (from GUI)

I am making a simple JavaFX college course project and I need a good way of dealing with threads, mainly running them while a certain flag is activated.
This is a simple sketch I came up with:
public class ListenerService extends Thread {
private static ArrayList<ListenerService> listeners = new ArrayList<>();
private ToggleButton button;
private File folder;
private SimpleBooleanProperty active = new SimpleBooleanProperty();
ListenerService(ToggleButton button, String pathname) {
this.button = button;
this.folder = new File(pathname);
button.setOnAction(event -> active.set(button.isSelected()));
active.addListener((ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean newValue)
-> {if (newValue.booleanValue()) start();});
listeners.add(this);
}
#Override
public void run() {
while(active.get())
System.out.print(".");
}
The process is as following:
The user dynamically creates a ToggleButton on the form. A
ListenerService object is created, to which a button and a directory
are assigned.
A listener is assigned to the button - if it's clicked - activate
the flag. Otherwise, deactivate. The flag here is a
SimpleBooleanProperty instance.
If the flag is switched on, run the thread. The thread will run
while the flag is active. If the user toggles the button again and
deactivates it, the condition in the while loop would fail and
thread should stop running.
As soon as I run the program, it freezes. I tried making the flag volatile, but nothing changed. Since the flag is controlled externally (from GUI), there isn't a way to make this method synchronized.
What am I doing wrong?

You basically create a new Thread that runs as long as the button is selected and exits when the button is not selected.
import javafx.application.Application;
import static javafx.application.Application.launch;
import javafx.scene.Scene;
import javafx.scene.control.ToggleButton;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;
public class ThreadApp extends Application {
public class Worker implements Runnable{
private boolean active;
public void setActive(boolean active) {
this.active = active;
}
#Override
public void run() {
while(active)
{
System.out.println("Active! " + System.currentTimeMillis());
}
}
}
public class WorkerToggle extends ToggleButton {
Worker worker;
public WorkerToggle(String text) {
super(text);
this.worker = new Worker();
setOnAction((event) -> {
if(isSelected())
{
worker.setActive(true);
Thread thread = new Thread(worker);
thread.setDaemon(true);
thread.start();
}else
{
worker.setActive(false);
}
});
}
}
#Override
public void start(Stage primaryStage) {
BorderPane rootPane = new BorderPane();
Scene scene = new Scene(rootPane);
rootPane.setCenter(new WorkerToggle("toggle me"));
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
This should work fine, but creating Threads can be expensive, so you might want to look into ThreadPoolExecutor if you notice some performance problems there.

In JavaFX you have the ability to use a scheduled service to run things off the main FX thread. Here is simple sample that might help.
public class JavaFXApplication3 extends Application {
#Override
public void start(Stage primaryStage) throws Exception {
PollingService service = new PollingService();
service.setPeriod(Duration.millis(1000)); // sysout every second
ToggleButton tb = new ToggleButton("Start Process");
tb.setOnAction(event -> {
System.out.println(tb.isSelected());
if(tb.isSelected()){
service.reset();
service.start();
}else {
service.cancel();
}
});
VBox vbox = new VBox(tb);
Scene scene = new Scene(vbox);
primaryStage.setScene(scene);
primaryStage.show();;
}
private class PollingService extends ScheduledService<Void> {
#Override
protected Task<Void> createTask() {
return new Task<Void>() {
#Override
protected Void call() {
System.out.print(".#.");
return null;
}
};
}
}
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
launch(args);
}
}

JavaFX 8: Unstable interactive TabPane when adding new Tab

I am making a highly interactive TabPane for viewing contact lists in JavaFX 8. For this I have made my own subclass of Tab, EditableTab, which has functionality for changing the name of the tab by double clicking on the name in the overview. When the user clicks the + sign to create a new contact list, I want the program to create a new tab, select it, then focus the name and select all the text - it is natural to name the contact list at once (similar to when you create a new file in windows).
My problem: This seems to be very unstable. Most of the times, it seems some kind of animation/transition problem arises, and the tab name ends up empty. Here is a screenshot of what usually, but not always, happens when the + button is clicked:
And here is what I want:
Here is the code for my EditableTab:
public class EditableTab extends Tab {
private Label lbl;
private TextField txtField;
public EditableTab(String text, Node content) {
super();
setContent(content);
lbl = new Label(text);
txtField = new TextField(text);
txtField.setStyle("-fx-background-color: transparent");
setGraphic(lbl);
setupInteractivity();
}
public TextField getTextField() {
return txtField;
}
private void setupInteractivity() {
lbl.setOnMouseClicked((mouseEvent) -> {
if (mouseEvent.getClickCount() == 2) {
showTextField();
}
});
txtField.setOnAction(event -> setGraphic(lbl));
txtField.focusedProperty().addListener(
(observable, oldValue, newValue) -> {
if (! newValue) {
lbl.setText(txtField.getText());
setGraphic(lbl);
}
});
}
public void showTextField() {
txtField.setPrefWidth(lbl.getWidth());
txtField.setText(lbl.getText());
setGraphic(txtField);
txtField.selectAll();
txtField.requestFocus();
}
}
And here is the code where the functionality is implemented:
private void addNewContactlist() {
Contactlist newList = new Contactlist();
newList.setName("New contact list");
contactlistApp.getContactlistData().add(newList);
ListView<Person> lv = new ListView<Person>(newList.getContacts());
setupListView(lv);
int position = tabPane.getTabs().size() - 1;
EditableTab tab = createEditableTab("New contact list", lv);
tabPane.getTabs().add(position, tab);
tabPane.getSelectionModel().select(tab);
tab.showTextField();
}
I suspect that the problem comes from some animation/transition timings, but that is really just a guess. I tried wrapping the showTextField() call in a Platform.runLater() with no luck.
Here is a small test app to replicate the issue:
public class TestApp extends Application {
TabPane tabPane = new TabPane();
#Override
public void start(Stage primaryStage) throws Exception {
Tab addNewContactlistTab = new Tab();
addNewContactlistTab.setClosable(false);
Label lbl = new Label("\u2795");
lbl.setOnMouseClicked(mouseEvent -> {
if (tabPane.getTabs().size() == 1) {
addNewTab();
}
});
addNewContactlistTab.setGraphic(lbl);
tabPane.getTabs().add(addNewContactlistTab);
addNewContactlistTab.selectedProperty().addListener(
(observable, oldValue, newValue) -> {
if (newValue && tabPane.getTabs().size() != 1) {
addNewTab();
}
});
Scene scene = new Scene(tabPane);
primaryStage.setScene(scene);
primaryStage.setWidth(600);
primaryStage.setHeight(400);
primaryStage.show();
}
private void addNewTab() {
int insertionIndex = tabPane.getTabs().size() - 1;
ListView<String> lv = new ListView<String>();
EditableTab tab = new EditableTab("Unnamed", lv);
tabPane.getTabs().add(insertionIndex, tab);
tabPane.getSelectionModel().select(tab);
tab.showTextField();
}
public static void main(String[] args) {
launch();
}
}

Here is my code for the RenamableTab class:
import javafx.application.Platform;
import javafx.scene.Node;
import javafx.scene.control.Label;
import javafx.scene.control.Tab;
import javafx.scene.control.TextField;
public class RenamableTab extends Tab {
private final Label label;
private final TextField textField;
public RenamableTab() {
this("New Tab", null);
}
public RenamableTab(String text) {
this(text, null);
}
public RenamableTab(String text, Node content) {
super();
label = new Label(text);
textField = new TextField(text);
setContent(content);
textField.setStyle("-fx-background-color: transparent");
setGraphic(label);
label.setOnMouseClicked((mouseEvent) -> {
if (mouseEvent.getClickCount() == 2) {
rename();
}
});
textField.setOnAction(event -> setGraphic(label));
textField.focusedProperty().addListener((observable, oldValue, newValue) -> {
if (!newValue) {
label.setText(textField.getText());
setGraphic(label);
}
});
}
public TextField getTextField() {
return textField;
}
public void rename() {
//textField.setPrefWidth(label.getWidth());
//textField.setText(label.getText());
setGraphic(textField);
new Thread() {
#Override
public void run() {
try {
Thread.sleep(300);
} catch (InterruptedException e) {
e.printStackTrace();
}
Platform.runLater(new Runnable() {
#Override
public void run() {
textField.selectAll();
textField.requestFocus();
}
});
}
}.start();
}
}
And here is my code for the FancyTabPane:
import javafx.event.EventHandler;
import javafx.scene.control.Label;
import javafx.scene.control.Tab;
import javafx.scene.control.TabPane;
import javafx.scene.input.MouseEvent;
public class FancyTabPane extends TabPane {
public FancyTabPane() {
Tab newTabTab = new Tab();
newTabTab.setClosable(false);
Label addLabel = new Label("\u2795");
addLabel.setOnMouseClicked(new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent paramT) {
System.out.println("mouse click");
addTab();
}
});
/*
* getSelectionModel().selectedItemProperty().addListener(new ChangeListener<Tab>() {
* #Override
* public void changed(ObservableValue<? extends Tab> paramObservableValue, Tab paramT1, Tab
* paramT2) {
* System.out.println("model");
* if (paramT1 == newTabTab) {
* System.out.println("tab");
* addTab();
* }
* }
* });
*/
newTabTab.setGraphic(addLabel);
getTabs().add(newTabTab);
}
public void addTab() {
RenamableTab newTab = new RenamableTab();
getTabs().add(getTabs().size() - 1, newTab);
getSelectionModel().select(newTab);
newTab.rename();
}
}
I am having issued with the new tab button when another tab is selected, not sure how you overcame that.

javafx how to use thread in fxml controller

I want to use thread I can use in simple program, but I can't use threads in fxml controller
Simple program:
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package javafxapplication3;
import java.util.Timer;
import java.util.TimerTask;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.application.Application;
import javafx.application.Platform;
import javafx.concurrent.Task;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.ProgressBar;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
/**
*
* #web http://java-buddy.blogspot.com/
*/
public class JavaFX_TimerTask extends Application {
final int MAX = 100;
Thread myTaskThread;
Thread myRunnableThread;
Timer myTimer;
MyTask myTask;
MyRunnable myRunnable;
MyTimerTask myTimerTask;
#Override
public void start(Stage primaryStage) {
myTask = new MyTask();
ProgressBar progressBarTask = new ProgressBar();
progressBarTask.setProgress(0);
progressBarTask.progressProperty().bind(myTask.progressProperty());
ProgressBar progressBarRunnable = new ProgressBar();
progressBarRunnable.setProgress(0);
myRunnable = new MyRunnable(progressBarRunnable);
ProgressBar progressBarTimerTask = new ProgressBar();
progressBarTimerTask.setProgress(0);
myTimerTask = new MyTimerTask(progressBarTimerTask);
Button btnStart = new Button("Start Task");
btnStart.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent t) {
myTaskThread = new Thread(myTask);
myTaskThread.start();
myRunnableThread = new Thread(myRunnable);
myRunnableThread.start();
myTimer = new Timer();
myTimer.scheduleAtFixedRate(myTimerTask, 80, 100);
}
});
VBox vBox = new VBox();
vBox.setPadding(new Insets(5, 5, 5, 5));
vBox.setSpacing(5);
vBox.getChildren().addAll(
new Label("Run in Thread(Task)"),
progressBarTask,
new Label("Run in Thread(Runnable)"),
progressBarRunnable,
new Label("Run in Timer and TimerTask"),
progressBarTimerTask,
btnStart);
StackPane root = new StackPane();
root.getChildren().add(vBox);
Scene scene = new Scene(root, 300, 250);
primaryStage.setTitle("java-buddy.blogspot.com");
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
class MyTask extends Task<Void>{
#Override
protected Void call() throws Exception {
for (int i = 1; i <= MAX; i++) {
updateProgress(i, MAX);
Thread.sleep(100);
}
return null;
}
}
class MyRunnable implements Runnable{
ProgressBar bar;
public MyRunnable(ProgressBar b) {
bar = b;
}
#Override
public void run() {
for (int i = 1; i <= MAX; i++) {
final double update_i = i;
//Not work if update JavaFX UI here!
//bar.setProgress(i/MAX);
//Update JavaFX UI with runLater() in UI thread
Platform.runLater(new Runnable(){
#Override
public void run() {
bar.setProgress(update_i/MAX);
}
});
try {
Thread.sleep(100);
} catch (InterruptedException ex) {
Logger.getLogger(JavaFX_TimerTask.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
}
class MyTimerTask extends TimerTask{
ProgressBar bar;
double count;
public MyTimerTask(ProgressBar b) {
bar = b;
count = 0;
}
#Override
public void run() {
bar.setProgress(count++/MAX);
if(count >= MAX){
myTimer.cancel();
}
}
}
}
Now, I want to use thread in a fxml controller:
public class DashboardController implements Initializable {
#Override
public void initialize(URL url, ResourceBundle rb) {
}
}
When I use thread, in initialize it doesn't show me any output.
How can I use thread?
Thank you.

JavaFx already runs threads -
JavaFx thread for GUI
Launch thread for background services.
If you need to make something like progress bar in which you want to run something over javafx thread then i would suggest use Services instead of thread as it can be used again and again while threads can't be.
Service<Void> ser = new Service<Void>() {
#Override protected Task createTask() {
return new Task<Void>() {
#Override protected Void call() throws InterruptedException {
// You code you want to execute in service backgroundgoes here
return null;
}
};
}
};
ser.setOnSucceeded((WorkerStateEvent event) -> {
// Anything which you want to update on javafx thread (GUI) after completion of background process.
});
ser.start();
You can use the service again and again with any variation like loop/recursion/switch -
ser.restart(); // Restart the service
ser.reset(); // Stops the service

Is your Controller initialized?
Do you set it (in the fxml/FXMLoader)?
If it your Controller is loaded this should work.
public class DashboardController implements Initializable {
#Override
public void initialize(URL url, ResourceBundle rb) {
myTask = new MyTask();
myTaskThread = new Thread(myTask);
myTaskThread.start();
}
}