Set FXML properties of custom type as attributes for custom javafx component

Question

I created custom JavaFX component as described in http://docs.oracle.com/javafx/2/fxml_get_started/custom_control.htm .

// Component.fxml
<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.control.Label?>
<?import javafx.scene.layout.VBox?>
<fx:root type="javafx.scene.layout.VBox" xmlns:fx="http://javafx.com/fxml">
    <Label fx:id="label"/>
</fx:root>

// Component.java
public class Component extends VBox {

    private final Entity entity;
    @FXML private Label label;

    public Component(@NamedArg("entity") Entity entity) {
        this.entity = entity;
        FXMLLoader fxmlLoader = new FXMLLoader();
        fxmlLoader.setLocation(Component.class.getResource("/Component.fxml"));
        fxmlLoader.setRoot(this);
        fxmlLoader.setController(this);

        try {
            fxmlLoader.load();
        } catch (IOException exception) {
            throw new RuntimeException(exception);
        }
    }

    @FXML
    private void initialize() {
        label.textProperty().set(this.entity.toString());
    }
}

Now i import it into root layout (custom component too).

// Root.fxml
<?xml version="1.0" encoding="UTF-8"?>

<?import foo.bar.javafx.Component?>
<?import javafx.scene.layout.AnchorPane?>
<fx:root type="javafx.scene.layout.AnchorPane"xmlns:fx="http://javafx.com/fxml">
// TODO How to pass entity?
<Component entity=?>
</Component>

// Root.java
public class Root extends AnchorPane {

    public Root() {
        FXMLLoader fxmlLoader = new FXMLLoader();
        fxmlLoader.setLocation(Root.class.getResource("/Root.fxml"));
        fxmlLoader.setRoot(this);
        fxmlLoader.setController(this);

        try {
            fxmlLoader.load();
        } catch (IOException exception) {
            throw new RuntimeException(exception);
        }
    }

}

How can i pass entity to Component? I know how to pass String - it's just <Component entity="text"> . But how to pass instance of arbitary class? PS Don't want to use Singleton pattern for this.

Answer 1

The solution for your problem could be that to separate the components from the controller like creating a Controller class for each of your controller: While the component is a VBox you can define an .fxml for it like:

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.layout.VBox?>
<VBox xmlns="http://javafx.com/javafx"
      xmlns:fx="http://javafx.com/fxml"
      fx:controller="stackoverflow.one.ComponentController">

</VBox>

It's controller which contains an entity:

public class ComponentController implements Initializable{

    private Entity entity;

    @Override
    public void initialize(URL location, ResourceBundle resources) {

    }

    public Entity getEntity() {
        return entity;
    }

    public void setEntity(Entity entity) {
        this.entity = entity;
    }
}

You can also change the Roor like this:

<?import javafx.scene.layout.AnchorPane?>
<AnchorPane xmlns="http://javafx.com/javafx"
            xmlns:fx="http://javafx.com/fxml"
            fx:controller="stackoverflow.one.RootController">
    <fx:include source="ComponentController.java" fx:id="component"/>

</AnchorPane>

Then in the controller you can get a reference of the ComponentController and you can set the entity, that you got from a service for example.

public class RootController implements Initializable {

    @FXML
    private ComponentController componentController;

    @Override
    public void initialize(URL location, ResourceBundle resources) {
        // getting Entity from a service or from any other sources
        //You may replace this line with an appropriate one for you.
        Entity entity = getEntity();
        componentController.setEntity(entity);
    }
}

Now you have separated the controllers and the view-components, you don't even need to load them because the FXMLLoader does it for you. This would be the basic concept how to pass an object to another view's controller.