tornadofx-guide

4. Basic Controls
If you need to save references to controls such as the TextFields, you can save them to
variables or properties since the functions return the produced controls. Until we learn more
robust modeling techniques, it is recommended you use the singleAssign() delegates to
ensure the properties are only assigned once.
import javafx.scene.control.TextField
import tornadofx.*
class MyView : View() {
var firstNameField: TextField by singleAssign()
var lastNameField: TextField by singleAssign()
}
override val root = vbox {
hbox {
label("First Name")
firstNameField = textfield()
}
hbox {
label("Last Name")
lastNameField = textfield()
}
button("LOGIN") {
useMaxWidth = true
action {
println("Logging in as ${firstNameField.text} ${lastNameField.text}")
}
}
}
Note that non-builder extension functions and properties have been added to different
controls as well. The useMaxWidth is an extended property for Node , and it sets the Node
to occupy the maximum width allowed. We will see more of these helpful extensions
throughout the next few chapters. We will also see each corresponding builder for each
JavaFX control. With the concepts understood above, you can read about these next
chapters start to finish or as a reference.
Builders for Basic Controls
The rest of this chapter will cover builders for common JavaFX controls like Button ,
Label , and TextField . The next chapter will cover builders for data-driven controls like
ListView , TableView , and TreeTableView .
Button
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