Live CSS tampering

CSSPlayground.java

package me.coley.recaf.ui.controls.theme;

import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.SplitPane;
import javafx.scene.image.Image;
import javafx.scene.input.KeyCode;
import javafx.stage.Stage;
import me.coley.recaf.ui.controls.text.TextPane;
import me.coley.recaf.ui.controls.text.model.Languages;

import java.io.*;
import java.lang.management.ManagementFactory;
import java.lang.management.PlatformLoggingMXBean;

import static me.coley.recaf.util.ClasspathUtil.resource;

public class CSSPlayground extends Application {
	public static void main(String[] args) {
		launch(args);
	}

	@Override
	public void start(Stage stage) throws Exception {


		FXMLLoader loader = new FXMLLoader(CSSPlayground.class.getResource("/sampler.fxml"));
		Parent root = loader.load();
		SplitPane sp = new SplitPane();

		Scene scene = new Scene(sp);
		scene.getStylesheets().add("style/text-theme-default.css");


		TextPane cssContent = new TextPane(null, Languages.find("css"));
		cssContent.setText(".text-area {}");
		cssContent.setEditable(true);
		cssContent.setOnKeyReleased(e -> {
			if(e.isControlDown() && e.getCode() == KeyCode.S) {
				String css = cssContent.getText();
				try {
					File temp = File.createTempFile("recaf", "tmpcss");
					temp.deleteOnExit();
					BufferedWriter bw = new BufferedWriter(new FileWriter(temp));
					bw.write(css);
					bw.close();
					scene.getStylesheets().clear();
					scene.getStylesheets().add("style/text-theme-default.css");
					scene.getStylesheets().add(temp.toURI().toString());
				} catch(Exception ex) {}
			}
		});


		sp.getItems().add(cssContent);
		sp.getItems().add(root);



		// Disable CSS logger, it complains a lot about non-issues
		ManagementFactory.getPlatformMXBean(PlatformLoggingMXBean.class).setLoggerLevel("javafx" +
				".css", "OFF");

		stage.setScene(scene);
		stage.getIcons().add(new Image(resource("icons/logo.png")));
		stage.setTitle("CSS Playground");
		stage.show();
	}
}

sampler.fxml

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

<?import javafx.scene.control.Button?>
<?import javafx.scene.control.CheckBox?>
<?import javafx.scene.control.ComboBox?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.control.ListView?>
<?import javafx.scene.control.Menu?>
<?import javafx.scene.control.MenuBar?>
<?import javafx.scene.control.MenuItem?>
<?import javafx.scene.control.SplitPane?>
<?import javafx.scene.control.Tab?>
<?import javafx.scene.control.TabPane?>
<?import javafx.scene.control.TableColumn?>
<?import javafx.scene.control.TableView?>
<?import javafx.scene.control.TextArea?>
<?import javafx.scene.control.TextField?>
<?import javafx.scene.control.TreeView?>
<?import javafx.scene.layout.AnchorPane?>
<?import javafx.scene.layout.BorderPane?>


<BorderPane xmlns="http://javafx.com/javafx/8.0.1" xmlns:fx="http://javafx.com/fxml/1">
   <top>
      <MenuBar BorderPane.alignment="CENTER">
        <menus>
          <Menu mnemonicParsing="false" text="File">
            <items>
              <MenuItem mnemonicParsing="false" text="Close" />
            </items>
          </Menu>
          <Menu mnemonicParsing="false" text="Edit">
            <items>
                  <MenuItem mnemonicParsing="false" text="Copy" />
                  <MenuItem mnemonicParsing="false" text="Cut" />
              <MenuItem mnemonicParsing="false" text="Delete" />
            </items>
          </Menu>
          <Menu mnemonicParsing="false" text="Help">
            <items>
              <MenuItem mnemonicParsing="false" text="About" />
            </items>
          </Menu>
        </menus>
      </MenuBar>
   </top>
   <center>
      <SplitPane dividerPositions="0.29797979797979796" prefHeight="366.0" prefWidth="657.0" BorderPane.alignment="CENTER">
        <items>
            <BorderPane>
               <center>
                  <TreeView editable="true" prefHeight="200.0" prefWidth="200.0" BorderPane.alignment="CENTER" />
               </center>
            </BorderPane>
            <TabPane SplitPane.resizableWithParent="false">
               <tabs>
                  <Tab text="Tab 1">
                     <content>
                      <AnchorPane minHeight="0.0" minWidth="0.0" prefHeight="160.0" prefWidth="100.0">
                           <children>
                              <Button layoutX="106.0" layoutY="14.0" mnemonicParsing="false" prefHeight="25.0" prefWidth="122.0" text="Button" />
                              <Label layoutX="14.0" layoutY="18.0" text="Example Text" />
                              <Label layoutX="14.0" layoutY="61.0" text="Example Text" />
                              <CheckBox layoutX="106.0" layoutY="61.0" mnemonicParsing="false" prefHeight="17.0" prefWidth="94.0" text="CheckBox" />
                              <Label layoutX="14.0" layoutY="101.0" text="Example Text" />
                              <ComboBox layoutX="106.0" layoutY="97.0" prefHeight="25.0" prefWidth="124.0" promptText="Prompt Text" />
                              <Button disable="true" layoutX="260.0" layoutY="16.0" mnemonicParsing="false" prefHeight="25.0" prefWidth="122.0" text="Button" />
                              <CheckBox disable="true" layoutX="260.0" layoutY="63.0" mnemonicParsing="false" prefHeight="17.0" prefWidth="94.0" text="CheckBox" />
                              <ComboBox disable="true" layoutX="260.0" layoutY="99.0" prefHeight="25.0" prefWidth="124.0" promptText="Prompt Text" />
                              <Label layoutX="14.0" layoutY="139.0" text="Example Text" />
                              <ListView layoutX="106.0" layoutY="139.0" prefHeight="200.0" prefWidth="126.0" />
                              <ListView layoutX="258.0" layoutY="139.0" prefHeight="200.0" prefWidth="126.0" />
                           </children>
                        </AnchorPane>
                     </content>
                  </Tab>
                  <Tab text="Tab 2">
                     <content>
                        <BorderPane>
                           <center>
                              <AnchorPane minHeight="0.0" minWidth="0.0" prefHeight="160.0" prefWidth="100.0">
                                 <children>
                                    <TextField layoutX="14.0" layoutY="14.0" prefHeight="25.0" prefWidth="200.0" text="Textfield" />
                                    <TextField disable="true" layoutX="229.0" layoutY="14.0" prefHeight="25.0" prefWidth="200.0" text="Textfield" />
                                    <TextArea layoutX="14.0" layoutY="50.0" prefHeight="97.0" prefWidth="199.0" text="# Sample Text&#10;Text: Area&#10;Example: Text" />
                                    <TextArea disable="true" layoutX="230.0" layoutY="50.0" prefHeight="97.0" prefWidth="199.0" text="# Sample Text&#10;Text: Area&#10;Example: Text" />
                                    <TableView layoutX="14.0" layoutY="159.0" prefHeight="163.0" prefWidth="410.0" tableMenuButtonVisible="true">
                                      <columns>
                                        <TableColumn prefWidth="75.0" text="C1" />
                                        <TableColumn prefWidth="75.0" text="C2" />
                                      </columns>
                                    </TableView>
                                 </children>
                              </AnchorPane>
                           </center>
                        </BorderPane>
                     </content>
                  </Tab>
               </tabs>
            </TabPane>
        </items>
      </SplitPane>
   </center>
</BorderPane>