How to set preferred width and height in fxml dynamically based on screen resolution javafx

Question

I am new to javafx. Is it possible to dynamically set preferred width and height in an fxml file based on screen resolution? I know how to get screen resolution and set it

Answer 1

You can (sort of) do this in FXML, but not with Scene Builder (as far as I am aware). You can use a fx:factory attribute to get the primary screen and define it in a <fx:define> block. Then use an expression binding to bind the prefWidth and prefHeight of the root pane to the width and height of the screen.

This looks like

MaximizedPane.fxml:

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

<?import javafx.scene.layout.StackPane?>
<?import javafx.scene.control.Label?>
<?import javafx.stage.Screen?>

<StackPane xmlns:fx="http://javafx.com/fxml/1"
           prefWidth="${screen.visualBounds.width}" 
           prefHeight="${screen.visualBounds.height}" >
    <fx:define>
        <Screen fx:factory="getPrimary" fx:id="screen"/>
    </fx:define>
    <Label text="A maximized pane"/>    
</StackPane>

and here's a quick test harness:

import java.io.IOException;

import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Scene;
import javafx.stage.Stage;

public class MaximizedFXMLPane extends Application {

    @Override
    public void start(Stage primaryStage) throws IOException {
        Scene scene = new Scene(FXMLLoader.load(getClass().getResource("MaximizedPane.fxml")));
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
}

(The reason there's no way to do this with Scene Builder is that it doesn't support any mechanism for inserting <fx:define> blocks in your FXML, among other things.)