FXML + Guice

FXML + Guice

There has been a very interesting thread in the JavaFX OTN forums about FXML and dependency injection. I went and downloaded Google Guice and wrote a small sample to try it all out. Things are not perfect quite yet (I still need full Unified Expression Language support added to FXML), but so very, very, very close!

What I ultimately hope to accomplish with FXML and CSS in JavaFX enterprise applications is that we (a) fully separate the visuals from the “controller”, (b) are left with a very simple “controller” that is highly testable, and (c) everything is highly modular.

CSS allows the designer to come in after the fact and modify the look of a UI without the developer’s help, and without a full build cycle. FXML allows a developer or designer to alter the structure of the view without a full build cycle. So (a) should be well in hand, especially if the controller itself can be injected rather than declared directly in the FXML file as it is today. (I’m OK with, even prefer, saying “I would like to have a FooController for this FXML file, if you please”, but what would really rock is if the FooController were an interface or abstract class rather than always being a concrete class, such that a DI framework like Guice could find the appropriate implementation and supply it).
(more…)

Correctly Checking KeyEvents

I was just writing a quick little application and I wanted to do something special whenever the user released the enter key inside a TextArea. You might be tempted to do it like this:

final TextArea editor = new TextArea();
editor.setOnKeyReleased(new EventHandler<KeyEvent>() {
    public void handle(KeyEvent t) {
        if (t.getCode() == KeyCode.ENTER) {
            System.out.println(editor.getText());
        }
    }
});

Can anybody spot the problem in this code? It correctly gets the key event, and it only prints out the text if the code of the key event is ENTER. The problem is that it also executes this code if you typed ALT+ENTER, or CTRL+ENTER, or any other combination of modifiers with the key code! JavaFX 2.0 contains a handy little class called KeyCombination which will handle all the annoying checking of key modifiers + key code to see if a specific key event matches. Here is the more correct version:

final TextArea editor = new TextArea();
editor.setOnKeyReleased(new EventHandler<KeyEvent>() {
    final KeyCombination combo = new KeyCodeCombination(KeyCode.ENTER);
    public void handle(KeyEvent t) {
        if (combo.match(t)) {
            System.out.println(editor.getText());
        }
    }
});

One extra line of code, and you get correct matching of the key events. Sweet!

FXML: Why It Rocks, And The Next Phase

JavaFX 2.0 shipped with a declarative XML-based language for defining user interfaces, called FXML. FXML is a key part of our strategy around making it easier to create user interfaces in Java. Certainly having a markup language has been attractive to web developers since it is a familiar and comfortable way to approach describing a user interface. But there are other key strategic reasons why FXML is important, how it fits into the broader JavaFX ecosystem, and how it helps you write testable user interfaces with minimal fuss. In essence, FXML helps you follow best practices while also making your life easier.

(more…)

JavaFX sessions at JavaOne 2011 online

The audio + slides for many of the JavaFX sessions at JavaOne 2011 are available on parleys.com. I have embedded a few we recommend you watch. There will be more arriving on parleys.com over the next couple weeks as they get processed.

Introduction to JavaFX :: Nicolas Lorain

JavaFX Architecture :: Richard Bair

JavaFX Architecture II :: Richard Bair