I'm trying to use Event Registration Method setOnKeyPressed twice inside the start method, but the method I invoke first doesn't work.
For example when I run this code and I click on a key from the keyboard Wow Wow Wow is not printed! And when I invoke the other method first, and I run the code and I click on the keyboard, also nothing shows up on the Pane but I get Wow Wow Wow printed on the console. I don't know why!
Here's the code:
public class Test extends Application {
String sms = "";
public static void main(String[] args) {
launch(args);
}
#Override
public void start(Stage stage) throws Exception {
Pane pane = new Pane();
Text txt = new Text();
txt.setLayoutX(30);
txt.setLayoutY(30);
pane.getChildren().add(txt);
pane.setOnKeyPressed(e -> {
System.out.println("Wow Wow Wow");
});
pane.setOnKeyPressed(e -> {
sms = sms + e.getText();
txt.setText(sms);
});
Scene scene = new Scene(pane, 300, 300);
stage.setScene(scene);
stage.setResizable(false);
stage.show();
pane.requestFocus();
}
}
The setOnXxx() are really convenience methods, behind the scenes it uses addEventHandler(EventType, EventHandler<Event>) which allows more than one handler per type.
addEventHandler(KeyEvent.KEY_PRESSED, evt -> doSomething());
Related
My controller class has a moveButton method that on button click moves the button to a new location. This works fine and is called by a number of buttons which do the same thing. I want to add a key listener so when a button has been clicked once, until a different button is clicked, the user can use the up arrow to move the button (ie call the same moveButton function). The below is how I have tried to implement it, I also tried putting the key listener in the initialize method but neither seem to be working. Any advice would be greatly appreciated!
public void moveButton(ActionEvent actionEvent) {
Button buttonPressed = (Button) actionEvent.getSource();
double newAnchor = getNewAnchor(AnchorPane.getBottomAnchor(buttonPressed)) // separate method that returns new anchor location
AnchorPane.setBottomAnchor(buttonPressed, newAnchor);
buttonPressed.getScene().setOnKeyPressed(new EventHandler<KeyEvent>() {
#Override
public void handle(KeyEvent event) {
if(event.getCode() == KeyCode.UP){
moveButton(actionEvent);
}
}
});
}
Don't treat the events like data that you need to pass around. Use them as triggers to do work. Generally, don't write generic event handlers that are called from multiple events and multiple nodes. Write short event handlers that just call methods to do something, and pass them the minimum from the event that they need to do the job.
If you do this, then it changes your thinking about how all of this stuff works and then it's just plain old Java, with no magic. And it's simple:
public class MoveButton extends Application {
private Node activeButton;
private Pane pane;
#Override
public void start(Stage primaryStage) throws Exception {
pane = new Pane();
Scene scene = new Scene(pane, 1200, 800);
primaryStage.setScene(scene);
primaryStage.show();
Button button1 = new Button("Button 1");
Button button2 = new Button("Button 2");
button2.setTranslateX(80);
button1.setOnAction(evt -> buttonClick(button1));
button2.setOnAction(evt -> buttonClick(button2));
pane.getChildren().addAll(button1, button2);
pane.setOnKeyPressed(evt -> moveButton(evt.getCode()));
}
private void moveButton(KeyCode keyCode) {
switch (keyCode) {
case UP -> activeButton.setTranslateY(activeButton.getTranslateY() - 30);
case RIGHT -> activeButton.setTranslateX(activeButton.getTranslateX() + 30);
case DOWN -> activeButton.setTranslateY(activeButton.getTranslateY() + 30);
case LEFT -> activeButton.setTranslateX(activeButton.getTranslateX() - 30);
}
}
private void buttonClick(Node button) {
activeButton = button;
pane.requestFocus();
}
}
This seems like it should be easy, so I must be missing something obvious: I have 4 standalone applications in the same package, us.glenedwards.myPackage,
myClass1 extends Application
myClass2 extends Application
etc...
I need each class to act as its own standalone application. Yet I want to be able to start the other 3 classes from the one I'm in by clicking a link. Android allows me to do this using Intents:
Intent intent = new Intent(this, EditData.class);
overridePendingTransition(R.layout.edit_data_scrollview, R.layout.state);
startActivity(intent);
I've tried starting myClass2 from myClass1 using
myClass2.launch("");
But I get an error, "Application launch must not be called more than once". The only way I can get it to work is if I remove both "extends application" and the start() method from myClass2, which means that myClass2 is no longer a standalone application.
How can I start myClass2, myClass3, or myClass4 from myClass1 with all 4 of them being standalone applications?
You can make this work by calling start(...) directly on a new instance of one of the Application subclasses, but it kind of feels like a bit of a hack, and is contrary to the intended use of the start(...) method. (Just semantically: a method called start in a class called Application should be executed when your application starts, not at some arbitrary point after it is already running.)
You should really think of the start method as the replacement for the main method in a traditional Java application. If you had one application calling another application's main method, you would (hopefully) come to the conclusion that you had structured things incorrectly.
So I would recommend refactoring your design so that your individual components are not application subclasses, but just plain old regular classes:
public class FirstModule {
// can be any Parent subclass:
private BorderPane view ;
public FirstModule() {
// create view; you could also just load some FXML if you use FXML
view = new BorderPane();
// configure view, populate with controls, etc...
}
public Parent getView() {
return view ;
}
// other methods as needed...
}
and, similarly,
public class SecondModule {
private GridPane view ;
public SecondModule {
view = new GridPane();
// etc etc
}
public Parent getView() {
return view ;
}
}
Now you can just do things like
FirstModule firstModule = new FirstModule();
Scene scene = new Scene(firstModule.getView());
Stage stage = new Stage();
stage.setScene(scene);
stage.show();
anywhere you need to do them. So you can create standalone applications for each module:
public class FirstApplication extends Application {
#Override
public void start(Stage primaryStage) {
Scene scene = new Scene(new FirstModule().getView());
primaryStage.setScene(scene);
primaryStage.show();
}
}
or you can instantiate them as part of a bigger application:
public class CompositeModule {
private HBox view ;
public CompositeModule() {
Button first = new Button("First Module");
first.setOnAction(e -> {
Parent view = new FirstModule().getView();
Scene scene = new Scene(view);
Stage stage = new Stage();
stage.initOwner(first.getScene().getWindow());
stage.setScene(scene);
stage.show();
});
Button second = new Button("Second Module");
second.setOnAction(e -> {
Parent view = new SecondModule().getView();
Scene scene = new Scene(view);
Stage stage = new Stage();
stage.initOwner(second.getScene().getWindow());
stage.setScene(scene);
stage.show();
});
HBox view = new HBox(10, first, second);
view.setAlignment(Pos.CENTER);
}
public Parent getView() {
return view ;
}
}
and
public class CompositeApplication extends Application {
#Override
public void start(Stage primaryStage) {
Scene scene = new Scene(new CompositeModule().getView(), 360, 150);
primaryStage.setScene(scene);
primaryStage.show();
}
}
The way I think of this is that Application subclasses represent an entire running application. Consequently it makes sense only to ever instantiate one such class once per JVM, so you should consider these inherently not to be reusable. Move any code you want to reuse into a different class somewhere.
have you tried this?
Runtime.getRuntime().exec("myClass1 [args]"); //put all args as you used in command
Also, handle/catch the exceptions, as needed.
I was right; it was a no-brainer. That's what I get for writing code on 4 hours of sleep:
myClass2 class2 = new myClass2();
try {
class2.start(stage);
} catch (Exception e) { e.printStackTrace(); } }
I'm writing a program in netbeans with javaFX
The view has several buttons in it with some bad buttons(like bombs is minesweeper), I'm trying to freeze the program when a bad button is pushed but i don't find how to do it
thanks!
There are various solutions to your problem. 2 among them are simply ignoring the action event or disabling the buttons like this:
public class ButtonAction extends Application {
final BooleanProperty buttonActionProperty = new SimpleBooleanProperty();
public static void main(String[] args) {
Application.launch(args);
}
#Override
public void start(Stage primaryStage) {
FlowPane root = new FlowPane();
CheckBox checkBox = new CheckBox( "Enabled");
checkBox.setSelected(true);
// solution 1: check if action is allowed and process it or not
buttonActionProperty.bind( checkBox.selectedProperty());
Button button = new Button( "Click Me");
button.setOnAction(e -> {
if( buttonActionProperty.get()) {
System.out.println( "Allowed, processing action");
} else {
System.out.println( "Not allowed, no action");
}
});
// solution 2: remove comments to activate the code
// button.disableProperty().bind(buttonActionProperty.not());
root.getChildren().addAll(checkBox, button);
primaryStage.setScene(new Scene(root, 600, 200));
primaryStage.show();
}
}
Add a ROOT typed event filter that consumes all kind of events (mouse, keyboard etc.)
btnThatHasHiddenMine.setOnAction(( ActionEvent event ) ->
{
System.out.println("Ohh no! You just stepped over the mine!");
getGameboardPane().addEventFilter( EventType.ROOT, Event::consume );
});
Add the filter to your GameboardPane only, since we don't want to freeze other part of the app.
first post on here so please be gentle...
I am fairly new to JavaFX and have successfully set up quite a complicated GUI which reads a csv file in order to populate certain components within the GUI.
I'm using a timeline in the intialize function for the GUI Controller which fires a button every second on the GUI - the button calls a function which reads the csv file form disc.. all this is working fine.
When I quit/exit the GUI stage I want to stop the timeline from running... but can't seem to manage this...
I have a small function which loads the Stage and also has an event listener to detect when it's closed... what I'd like to do is be able to close the timeline at the commented line... in the try/catch section.
public void Show_MACD() throws IOException
{
Parent root = FXMLLoader.load(getClass().getResource("MACD Turbo.fxml"));
Scene scene = new Scene(root);
Stage stage = new Stage();
stage.setScene(scene);
stage.setTitle("FX AlgoTrader MACD Turbo");
stage.show();
JavaFX.thisstage=stage;
stage.setOnCloseRequest(new EventHandler<WindowEvent>() {
#Override
public void handle(WindowEvent we) {
LoginController sp=new LoginController();
try {
//how can I stop the timeline here?
sp.Show_Products(); // this loads up another stage - a menu in fact
} catch (IOException ex) {
Logger.getLogger(MACD_Controller.class.getName()).log(Level.SEVERE, null, ex);
}
}
});
//System.out.println("running");
}
Here's the section in the initialize function where the timeline is set up and run from....(this is in the same class as the controller called 'MACD_Controller' which is also home to the 'Show_MACD' function which has a event listener for window close events.. that's kind of where I would like to stop the timeline ie when the window closes)
#Override
public void initialize(URL url, ResourceBundle rb) {
final Timeline timeline = new Timeline(new KeyFrame(Duration.seconds(1), new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent actionEvent)
{
Refresh.fire(); //Refresh is a button on the GUI which calls the csv file
}
}));
timeline.setCycleCount(Timeline.INDEFINITE);
timeline.play();
}
I know I need to somehow create a reference to 'timeline' so that I can use the 'timeline.stop' function... I've tried all sorts of mumbo jumbo but I keep getting an NPE.
I know this is super basic but I'm a bit stuck..
Cheers
Crispin
I can't figure out how to create a modal window in JavaFX. Basically I have file chooser and I want to ask the user a question when they select a file. I need this information in order to parse the file, so the execution needs to wait for the answer.
I've seen this question but I've not been able to find out how to implement this behavior.
In my opinion this is not good solution, because parent window is all time active.
For example if You want open window as modal after click button...
private void clickShow(ActionEvent event) {
Stage stage = new Stage();
Parent root = FXMLLoader.load(
YourClassController.class.getResource("YourClass.fxml"));
stage.setScene(new Scene(root));
stage.setTitle("My modal window");
stage.initModality(Modality.WINDOW_MODAL);
stage.initOwner(
((Node)event.getSource()).getScene().getWindow() );
stage.show();
}
Now Your new window is REALY modal - parent is block.
also You can use
Modality.APPLICATION_MODAL
Here is link to a solution I created earlier for modal dialogs in JavaFX 2.1
The solution creates a modal stage on top of the current stage and takes action on the dialog results via event handlers for the dialog controls.
JavaFX 8+
The prior linked solution uses a dated event handler approach to take action after a dialog was dismissed. That approach was valid for pre-JavaFX 2.2 implementations. For JavaFX 8+ there is no need for event handers, instead, use the new Stage showAndWait() method. For example:
Stage dialog = new Stage();
// populate dialog with controls.
...
dialog.initOwner(parentStage);
dialog.initModality(Modality.APPLICATION_MODAL);
dialog.showAndWait();
// process result of dialog operation.
...
Note that, in order for things to work as expected, it is important to initialize the owner of the Stage and to initialize the modality of the Stage to either WINDOW_MODAL or APPLICATION_MODAL.
There are some high quality standard UI dialogs in JavaFX 8 and ControlsFX, if they fit your requirements, I advise using those rather than developing your own. Those in-built JavaFX Dialog and Alert classes also have initOwner and initModality and showAndWait methods, so that you can set the modality for them as you wish (note that, by default, the in-built dialogs are application modal).
You can create application like my sample. This is only single file JavaFX application.
public class JavaFXApplication1 extends Application {
#Override
public void start(Stage primaryStage) {
Button btn = new Button();
btn.setText("Say 'Hello World'");
btn.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent event) {
Stage stage;
stage = new Stage();
final SwingNode swingNode = new SwingNode();
createSwingContent(swingNode);
StackPane pane = new StackPane();
pane.getChildren().add(swingNode);
stage.initModality(Modality.APPLICATION_MODAL);
stage.setTitle("Swing in JavaFX");
stage.setScene(new Scene(pane, 250, 150));
stage.show();
}
});
StackPane root = new StackPane();
root.getChildren().add(btn);
Scene scene = new Scene(root, 300, 250);
primaryStage.setTitle("Hello World!");
primaryStage.setScene(scene);
primaryStage.show();
}
private void createSwingContent(final SwingNode swingNode) {
SwingUtilities.invokeLater(() -> {
try {
Path currentRelativePath = Paths.get("");
String s = currentRelativePath.toAbsolutePath().toString();
JasperDesign jasperDesign = JRXmlLoader.load(s + "/src/reports/report1.jrxml");
String query = "SELECT * FROM `accounttype`";
JRDesignQuery jrquery = new JRDesignQuery();
jrquery.setText(query);
jasperDesign.setQuery(jrquery);
JasperReport jasperReport = JasperCompileManager.compileReport(jasperDesign);
JasperPrint JasperPrint = JasperFillManager.fillReport(jasperReport, null, c);
//JRViewer viewer = new JRViewer(JasperPrint);
swingNode.setContent(new JRViewer(JasperPrint));
} catch (JRException ex) {
Logger.getLogger(AccountTypeController.class.getName()).log(Level.SEVERE, null, ex);
}
});
}
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
launch(args);
}
}