JavaFX – how to set default active control

javajavafxjavafx-2

I've got single window JavaFX application, created from one of the JavaFX tutorial.

I'm setting new window content by following function:

private Initializable replaceSceneContent(final String fxml) throws Exception {

    // wczytanie fxml
    FXMLLoader loader = new FXMLLoader();
    InputStream in = Main.class.getResourceAsStream(fxml);
    loader.setBuilderFactory(new JavaFXBuilderFactory());
    loader.setLocation(Main.class.getResource(fxml));
    AnchorPane page;
    try {
        page = (AnchorPane) loader.load(in);
    } finally {
        in.close();
    }

    Scene scene = new Scene(page, w, h);
    stage.setScene(scene);
    return (Initializable) loader.getController();
}

But i want to choose one of TextFields from this fxml file to be active by default. How to do this? I've tried to call requestFocus method in controller's initialize method but it didn't work. I haven't found any suitable property in TextField class either in AnchorPane class (AnchorPane is root element of fxml controls tree).

Best Answer

Try wrapping your requestFocus() call with PlatForm.runlater

Platform.runLater(new Runnable() {
    public void run() {
        textField.requestFocus();
    }
});

Related Solutions

Java – How to test a class that has private methods, fields or inner classes

Update:

Some 10 years later perhaps the best way to test a private method, or any inaccessible member, is via @Jailbreak from the Manifold framework.
@Jailbreak Foo foo = new Foo();
// Direct, *type-safe* access to *all* foo's members
foo.privateMethod(x, y, z);
foo.privateField = value;
This way your code remains type-safe and readable. No design compromises, no overexposing methods and fields for the sake of tests.

If you have somewhat of a legacy Java application, and you're not allowed to change the visibility of your methods, the best way to test private methods is to use reflection.

Internally we're using helpers to get/set private and private static variables as well as invoke private and private static methods. The following patterns will let you do pretty much anything related to the private methods and fields. Of course, you can't change private static final variables through reflection.

Method method = TargetClass.getDeclaredMethod(methodName, argClasses);
method.setAccessible(true);
return method.invoke(targetObject, argObjects);

And for fields:

Field field = TargetClass.getDeclaredField(fieldName);
field.setAccessible(true);
field.set(object, value);

Notes:
1. TargetClass.getDeclaredMethod(methodName, argClasses) lets you look into private methods. The same thing applies for getDeclaredField.
2. The setAccessible(true) is required to play around with privates.

Java – How to efficiently iterate over each entry in a Java Map

Map<String, String> map = ...
for (Map.Entry<String, String> entry : map.entrySet()) {
    System.out.println(entry.getKey() + "/" + entry.getValue());
}

On Java 10+:

for (var entry : map.entrySet()) {
    System.out.println(entry.getKey() + "/" + entry.getValue());
}

Best Answer

Related Solutions

Java – How to test a class that has private methods, fields or inner classes

Java – How to efficiently iterate over each entry in a Java Map

Related Topic