javafx
FXML and Controllers
Define Blocks and
Example
Sometimes a element needs to be created outside of the usual object structure in the fxml.
This is where Define Blocks come into play:
Contents inside a <fx:define> element are not added to the object created for the parent element.
Every child element of the <fx:define> needs a fx:id attribute.
Objects created this way can be later referenced using the <fx:reference> element or by using expression binding.
The <fx:reference> element can be used to reference any element with a fx:id attribute that is handled before the <fx:reference> element is handled by using the same value as the fx:id attribute of the referenced element in the source attribute of the <fx:reference> element.
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.text.*?>
<?import java.lang.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<VBox xmlns:fx="http://javafx.com/fxml/1" prefHeight="300.0" prefWidth="300.0" xmlns="http://javafx.com/javafx/8">
<children>
<fx:define>
<String fx:value="My radio group" fx:id="text" />
</fx:define>
<Text>
<text>
<!-- reference text defined above using fx:reference -->
<fx:reference source="text"/>
</text>
</Text>
<RadioButton text="Radio 1">
<toggleGroup>
<ToggleGroup fx:id="group" />
</toggleGroup>
</RadioButton>
<RadioButton text="Radio 2">
<toggleGroup>
<!-- reference ToggleGroup created for last RadioButton -->
<fx:reference source="group"/>
</toggleGroup>
</RadioButton>
<RadioButton text="Radio 3" toggleGroup="$group" />
<!-- reference text defined above using expression binding -->
<Text text="$text" />
</children>
</VBox>
