tornadofx-guide

3. Components
Components
JavaFX uses a theatrical analogy to organize an Application with Stage and Scene
components.
TornadoFX builds on this by providing View , Controller , and Fragment components.
While the Stage , and Scene are used by TornadoFX, the View , Controller , and
Fragment introduces new concepts that streamline development. Many of these
components are automatically maintained as singletons, and can communicate to each
other through TornadoFX's simple dependency injections or direct instantiation.
You also have the option to utilize FXML which will be discussed in Chapter 10. But first, lets
extend App to create an entry point that launches a TornadoFX application.
App and View Basics
To create a TornadoFX application, you must have at least one class that extends App . An
App is the entry point to the application and specifies the initial View . It does in fact extend
JavaFX Application , but you do not necessarily need to specify a start() or main()
method.
Extend App to create your own implementation and specify the primary view as the first
constructor argument.
class MyApp: App(MyView::class)
A View contains display logic as well as a layout of Nodes, similar to the JavaFX Stage . It
is automatically managed as a singleton. When you declare a View you must specify a
root property which can be any Parent type, and that will hold the View's content.
In the same Kotlin file or in a new file, extend a class off of View . Override the abstract
root property and assign it VBox or any other Node you choose.
class MyView: View() {
}
override val root = VBox()
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