Using the JavaFX UI Controls - JavaFX 8: A Definitive Guide to Building Desktop, Mobile, and Embedded Java Clients - page 259

As shown in the following snippet from Listing 6-12, the content of a ScrollPane is a Node subclass, in this case
a VBox that contains several nodes. When the contents are larger than the viewable area of the ScrollPane , horizontal
and/or vertical scrollbars appear according to the specified hbarPolicy and vbarPolicy .

ScrollPane scrollPane = new ScrollPane(variousControls);
scrollPane.setHbarPolicy(ScrollPane.ScrollBarPolicy.NEVER);
scrollPane.setVbarPolicy(ScrollPane.ScrollBarPolicy.AS_NEEDED);
scrollPane.setOnMousePressed((MouseEvent me) -> {
if (me.getButton() == MouseButton.SECONDARY) {
contextMenu.show(stage, me.getScreenX(), me.getScreenY());
}
});

Other useful ScrollPane properties include:
•

pannable , which enables the user to pan the contents of the ScrollPane by dragging it with
the mouse

fitToWidth/fitToHeight , which causes the content node (if resizable) to be stretched to fit
the width/height of the ScrollPane
Note that we're using an onMousePressed() event handler in the previous snippet. We walk through that
functionality after discussing some of the UI controls that are contained within our ScrollPane , beginning with
the CheckBox .

•

Using a CheckBox
As you experienced in Step 17 of the exercise, the ScrollPane shown in Figure 6-9 contains a CheckBox .
When the CheckBox is clicked, a message is printed to the Java console indicating the state of its selected property.
The following code snippet, from Listing 6-12, implements this functionality in the StarterApp program:

final CheckBox checkBox = new CheckBox("CheckBox");
checkBox.setOnAction(e -> {
System.out.print(e.getEventType() + " occurred on CheckBox");
System.out.print(", and selectedProperty is: ");
System.out.println(checkBox.selectedProperty().getValue());
});

A CheckBox may also represent a third indeterminate state by setting its allowIndeterminate property to
true. This third state is typically represented in the CheckBox with a dash, and is useful for indicating that the state
represented by the CheckBox is unknown.

Defining a RadioButton
In Step 18 of the previous exercise, you selected each of the RadioButton controls shown in Figure 6-9 . As a result,
a message was printed to the Java console indicating which RadioButton was selected. The following code snippet,
from Listing 6-12, implements this functionality in the StarterApp program:

final ToggleGroup radioToggleGroup = new ToggleGroup();
RadioButton radioButton1 = new RadioButton("RadioButton1");
radioButton1.setToggleGroup(radioToggleGroup);