I am just changing from AWT to JavaFX and im wondering how to work with focus.
For Exampe: In AWT I wrote something like that:
Button bFocus = new Button("Focus");
bFocus.addFocusListener(new FocusListener() {
public void focusGained(FocusEvent e) {
System.out.println("Having the Focus");
}
public void focusLost(FocusEvent e) {
System.out.println("Lost the Focus");
}
});
But how does it work in JavaFX? I tried many different things, but that doesnt work...
JavaFX has an API that defines observable properties with which you can register listeners and respond when they change. Almost all state that belongs to UI elements in JavaFX is represented by these properties, allowing you to register a listener that responds when they change.
So, for example, the superclass of all UI elements, Node has a ReadOnlyBooleanProperty called focused, with which you can register a listener:
Button bFocus = new Button("Focus");
bFocus.focusedProperty().addListener((obs, wasFocused, isNowFocused) -> {
if (isNowFocused) {
System.out.println("Having the Focus");
} else {
System.out.println("Lost the Focus");
}
});
I thought it might be helpful to see an example which specifies the ChangeListener as an anonymous inner class like James_D mention here.
TextField yourTextField = new TextField();
yourTextField.focusedProperty().addListener(new ChangeListener<Boolean>()
{
#Override
public void changed(ObservableValue<? extends Boolean> arg0, Boolean oldPropertyValue, Boolean newPropertyValue)
{
if (newPropertyValue)
{
System.out.println("Textfield on focus");
}
else
{
System.out.println("Textfield out focus");
}
}
});
I hope this answer is helpful!
Related
I'm writing a JavaFX program with a TableView called 'table' and 2 buttons called 'previous' & 'next'.
Here is part of the code:
previous.setOnAction(event -> {
table.getSelectionModel().selectPrevious();
});
next.setOnAction(event -> {
table.getSelectionModel().selectNext();
});
However, if I keep pressing the buttons, the table will not scroll automatically to keep the selected item visible. So I modified the code like this :
previous.setOnAction(event -> {
table.getSelectionModel().selectPrevious();
table.scrollTo(table.getSelectionModel().getSelectedItem());
});
next.setOnAction(event -> {
table.getSelectionModel().selectNext();
table.scrollTo(table.getSelectionModel().getSelectedItem());
});
But it will always try to keep the selected item at the top of the visible region. If I keep pressing 'next'. The selected item will stay at the top instead of staying at the bottom.
I want to mimic the natural behavior of a tableview in the way that if I press up or down on the keyboard with something selected, the tableview will scroll automatically to keep the selected item visible.
How should I modify the code to make the auto scrolling more natural when I press the buttons?
Thanks
The problem is
missing fine-grained control of scrollTo target location on application level
the (somewhat unfortunate) implementation of virtualizedControl.scrollTo(index) which (ultimately) leads to calling flow.scrollToTop(index)
There's a long-standing RFE (reported 2014!) requesting better control from application code. Actually, VirtualFlow has public methods (scrollToTop, scrollTo, scrollPixels) providing such, only they are not passed on to the control layer (getVirtualFlow in VirtualContainerBase is final protected), so can't be overridden in a custom skin. Since fx12, we can hack a bit, and expose the onSelectXX of Tree/TableViewSkin and use those, either directly in application code (example below) or in a custom TableView.
Example code:
public class TableSelectNextKeepVisible extends Application {
/**
* Custom table skin to expose onSelectXX methods for application use.
*/
public static class MyTableSkin<T> extends TableViewSkin<T> {
public MyTableSkin(TableView<T> control) {
super(control);
}
/**
* Overridden to widen scope to public.
*/
#Override
public void onSelectBelowCell() {
super.onSelectBelowCell();
}
/**
* Overridden to widen scope to public.
*/
#Override
public void onSelectAboveCell() {
super.onSelectAboveCell();
}
}
private Parent createContent() {
TableView<Locale> table = new TableView<>(FXCollections.observableArrayList(Locale.getAvailableLocales())) {
#Override
protected Skin<?> createDefaultSkin() {
return new MyTableSkin<>(this);
}
};
TableColumn<Locale, String> country = new TableColumn<>("Column");
country.setCellValueFactory(new PropertyValueFactory<>("displayLanguage"));
table.getColumns().addAll(country);
Button next = new Button("next");
next.setOnAction(e -> {
table.getSelectionModel().selectNext();
// scrolls to top
// table.scrollTo(table.getSelectionModel().getSelectedIndex());
((MyTableSkin<?>) table.getSkin()).onSelectBelowCell();
});
Button previous = new Button("previous");
previous.setOnAction(e -> {
table.getSelectionModel().selectPrevious();
// scrolls to top
// table.scrollTo(table.getSelectionModel().getSelectedIndex());
((MyTableSkin<?>) table.getSkin()).onSelectAboveCell();
});
BorderPane content = new BorderPane(table);
content.setBottom(new HBox(10, next, previous));
return content;
}
#Override
public void start(Stage stage) throws Exception {
stage.setScene(new Scene(createContent()));
stage.show();
}
public static void main(String[] args) {
launch(args);
}
}
try using getSelectedIndex as follows instead of using getSelectedItem
previous.setOnAction(event -> {
table.getSelectionModel().selectPrevious();
table.scrollTo(table.getSelectionModel().getSelectedIndex());
});
Platform.runLater( () -> TABLE_NAME.scrollTo(TABLE_INFORMATION_LIST.getList().size()-index) );
should work if you call it whenever you add information to the table.
i've been trying to get the grasp of afterburner.fx for few days now but i cant figure out this problem. please help
there are three tabs in a tab pane
tabPane.getTabs().get(0).setContent(new FirstView().getView());
tabPane.getTabs().get(1).setContent(new SecondView().getView());
tabPane.getTabs().get(2).setContent(new ThirdView().getView());
these are not named firstview, secondview etc. it's for demonstration...
now each of these views have a reload method:
firstView.reload()
secondView.reload()
thirdView.reload()
and i have setup a listener for tab changes so that i can reload these views once they come into view
tabPane.getSelectionModel().selectedItemProperty().addListener((o, oldValue, newValue) -> {
newValue.getView().reload(); // of course this cant be done like this
})
how to reload the view of the tab once it comes into view.?
You can add listeners to the individual tabs instead of to the tab pane:
FirstView firstView = new FirstView();
Tab tab0 = tabs.getTabs().get(0);
tab0.selectedProperty().addListener((obs, wasSelected, isSelected) -> {
if (isSelected) {
firstView.reload();
}
});
tab0.setContent(firstView.getView());
// etc
i managed to find a work around for this. i made two new classes, one that extends FXMLView and another that extends Tab.
public abstract class ReloadableView extends FXMLView {
public abstract void reload();
}
and
public class ReloadingTab<V extends ReloadableView> extends Tab {
private V view;
public ReloadingTab(String text, V view) {
super(text, view.getView());
this.view = view;
}
public V getView() {
return view;
}
}
and finally added the listener
tabPane.getSelectionModel().selectedItemProperty().addListener((o, oldValue, newValue) -> {
ReloadingTab tab = (ReloadingTab) newValue;
tab.getView().reload();
});
sorry if my question didnt make any sense. i hope someone finds this useful.
I have a log in form that i was creating and i want the TextField ActionEvent to be used also in the Button but I don't know what to do. In Swing I've seen it that it can recycle an ActionEvent and use it in other like TextField but i don't know how to do it in JavaFX.
Here is a code for my TextField with an ActionEvent
and I want to apply this also to my Button so I dont have to create another method with just the same function but different Component. Thanks
passField.setOnKeyPressed(new EventHandler<KeyEvent>()
{
#Override
public void handle(KeyEvent e)
{
if(e.getCode().equals(KeyCode.ENTER))
{
if(admin.equals(userField.getText()) && password.equals(passField.getText()))
{
textInfo.setText("WELCOME " + passField.getText());
textInfo.setTextFill(Color.BLACK);
}
else
{
userField.clear();
passField.clear();
textInfo.setText("Incorrect username or password");
textInfo.setTextFill(Color.RED);
}
}
}
});
You will have to find a shared Event that both the Button and the TextField support.
In your example you are attaching a handler for a KeyEvent watching for the ENTER key, which is equivalent to an ActionEvent. luckily the Button supports it too.
Create a shared EventHandler:
final EventHandler<ActionEvent> myHandler = e -> {
if(admin.equals(userField.getText()) && password.equals(passField.getText())) {
textInfo.setText("WELCOME " + passField.getText());
textInfo.setTextFill(Color.BLACK);
}
else {
userField.clear();
passField.clear();
textInfo.setText("Incorrect username or password");
textInfo.setTextFill(Color.RED);
}
}
Which you can now attach twice (or even more often):
button.setOnAction(myHandler);
passField.setOnAction(myHandler);
EDIT
Without lambda expression:
final EventHandler<ActionEvent> myHandler = new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent e)
{
if(admin.equals(userField.getText()) && password.equals(passField.getText())) {
textInfo.setText("WELCOME " + passField.getText());
textInfo.setTextFill(Color.BLACK);
}
else {
userField.clear();
passField.clear();
textInfo.setText("Incorrect username or password");
textInfo.setTextFill(Color.RED);
}
}
});
Ok if i have the following code:
protected void makebutton(String name){
JButton button = new JButton(name);
mypanel.add(button);
}
then:
makebutton("Button1");
makebutton("Button2");
makebutton("Button3");
How can i add ActionListener to them. Which name do I use for ActionListener, tried many combination but no success.
What you could do is make the method return a Button. Thats way you can use the button variable else where in your program. What's happening in your case is that the button is encapsulated. so you can't access from anywhere else in your code. Something like this
private JButton makeButton(String name){
JButton button = new JButton(name);
button.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
// code action to perform
}
});
return button;
}
You can use the method when you declare the button
JButton aButton = makeButton();
panel.add(aButton);
The more reasonable way to do it is just create the buttons without a method.
JButtton button = new JButton("Button");
panel.add(button);
button.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
// code action to perform
}
});
I don't really see the need for a method.
Another option is to create a custom listener class
public class GUI {
JButton button1;
JButton button2;
public GUI(){
button1 = new JButton();
button2 = new JButton();
button1.addActionListner(new ButtonListener());
button2.addActionListner(new ButtonListener());
}
private class ButtonListener implements ActionListener{
public void actionPerformed(ActionEvent e){
if (e.getSource() == button1){
// do something
} else if (e.getSource() == button2){
// something
}
}
}
}
protected void makebutton(String name){
final String n = name;
JButton button = new JButton(name);
mypanel.add(button);
button.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
if(n=="Button1"){
button1ActionListener();
}else if(n=="Button2"){
button2ActionListener();
}
}
});
}
you have to create more methods for every button.
I think peeskillet's second code is the good one.
I want to know whether how to capture the button clicked with AspectJ and get its parameter (eg. button name). I think for having more generalized capturing with AspectJ, it shoudl be used MouseListener so it can capture other UI elements in general!
Example:
In a GUI example I have defined 2 buttons that take some actions
public JButton btn1 = new JButton("Test1");
public JButton btn2 = new JButton("Test2");
btn1.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
//take some actions
}
}
btn2.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
//take some actions
}
}
How to capture these buttons with AspectJ, and get their parameters (eg. name)?
It is possible. I have provided two examples. The first that prints out for every JButton that has an ActionListener. The other example only prints out if a specific buttons is clicked.
Prints the text for every JButton clicked with an ActionListener:
#Pointcut("execution(* *.actionPerformed(*)) && args(actionEvent)")
public void buttonPointcut(ActionEvent actionEvent) {}
#Before("buttonPointcut(actionEvent)")
public void beforeButtonPointcut(ActionEvent actionEvent) {
if (actionEvent.getSource() instanceof JButton) {
JButton clickedButton = (JButton) actionEvent.getSource();
System.out.println("Button name: " + clickedButton.getText());
}
}
Prints the text for a specific JButton:
public static JButton j1;
#Pointcut("execution(* *.actionPerformed(*)) && args(actionEvent) && if()")
public static boolean button1Pointcut(ActionEvent actionEvent) {
return (actionEvent.getSource() == j1);
}
#Before("button1Pointcut(actionEvent)")
public void beforeButton1Pointcut(ActionEvent actionEvent) {
// logic before the actionPerformed() method is executed for the j1 button..
}
UPDATED:
You can do this in many different ways. For example add your buttons to the aspect directly. But I prefere to use a enum object between (ButtonManager in this case), so the code does not know about the aspect. And since the ButtonManager is an enum object, it is easy for the aspect to retrieve values from it.
I just tested it with a Swing button class from Oracle and it works. In the Swing class:
b1 = new JButton("Disable middle button", leftButtonIcon);
ButtonManager.addJButton(b1);
AspectJ is extremely powerful when it comes to manipulating classes, but it can not weave advises into specific objects since objects is not created at the time of weaving. So you can only work with objects at runtime and that is why I have added the addJButton(..) method above. That enables the aspect to check the advised button against a list of registered buttons.
The ButtonManager class:
public enum ButtonManager {
;
private static Collection<JButton> buttonList = new LinkedList<JButton>();
public static void addJButton(JButton jButton) {
buttonList.add(jButton);
}
public static Collection<JButton> getButtonList() {
return buttonList;
}
}
Modified pointcut and advice to only print the name of the buttons registered in the ButtonManager:
#Pointcut("execution(* *.actionPerformed(*)) && args(actionEvent) && if()")
public static boolean buttonListPointcut(ActionEvent actionEvent) {
Collection<JButton> buttonList = ButtonManager.getButtonList();
JButton registeredButton = null;
for (JButton jButton : buttonList) {
if (actionEvent.getSource() == jButton) {
registeredButton = jButton;
}
}
return registeredButton != null;
}
#Before("buttonListPointcut(actionEvent)")
public void beforeButtonListPointcut(ActionEvent actionEvent) {
JButton clickedButton = (JButton) actionEvent.getSource();
System.out.println("Registered button name: " + clickedButton.getText());
}
UPDATED 2
Okay, I believe I understand what you want. You want to listen to mouse events. That is possible. The downside is that you have to register all your GUI components that you want to listen for clicks with a mouse listener. It is not enough to register the JPanel of the JFrame with a MouseListener. So if you only have registered an ActionListener for your buttons, you also have to add a mouse listener.
I have created a quick solution that works for me. It only shows that it works. I have not tried to make the solution generic with many different GUI objects. But that should be quite easy to refactor in when you have got the basics to work.
In the Swing class:
private class MouseListener extends MouseInputAdapter {
public void mouseClicked(MouseEvent e) {}
}
In the init method of the Swing class:
MouseListener myListener = new MouseListener();
btn1.addMouseListener(myListener);
btn2.addMouseListener(myListener);
In the Aspect class:
#Pointcut("execution(* *.mouseClicked(*)) && args(mouseEvent)")
public void mouseEventPointcut(MouseEvent mouseEvent) {}
#Before("mouseEventPointcut(mouseEvent)")
public void beforeMouseEventPointcut(MouseEvent mouseEvent) {
if (mouseEvent.getSource() instanceof JButton) {
JButton clickedButton = (JButton) mouseEvent.getSource();
System.out.println("aspectJ --> mouseClicked: " + clickedButton.getText());
}
}
This results in the following output in the console:
aspectJ --> mouseClicked: Test1
I hope it helps!