import javafx.scene.control.ButtonType;
import javafx.scene.control.Dialog;
import javafx.scene.control.ButtonBar.ButtonData;

public class TestDialog extends Dialog<String> {
    
    public TestDialog() {

        this.setTitle("Teszt");
        ButtonType type = new ButtonType("Ok", ButtonData.OK_DONE);
        this.getDialogPane().getButtonTypes().add(type);
        this.setContentText("Teszt");
    }
    
}