JavaFX, SceneBuilder, MenuItem --> Image - javafx

Question

I recently found the google-material-icons and now i want to make my application more good looking using icons. Right now i want to add an image to the application close MenuItem. With SceneBuilder you can just add items, but what i now wanna do is at least still use fxml. I have two questions:
Can I edit the fxml without it being overwritten by scenebuilder again?
how can i add the icon to MenuItems?
Thank you very much. In case you need it, here my FXML:
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.geometry.Insets?>
<?import javafx.scene.control.Menu?>
<?import javafx.scene.control.MenuBar?>
<?import javafx.scene.control.MenuItem?>
<?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.layout.BorderPane?>
<?import javafx.scene.layout.VBox?>
<BorderPane fx:id="borderPane" maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="400.0" prefWidth="600.0" stylesheets="#../styles/Styles.css" xmlns="http://javafx.com/javafx/8.0.111" xmlns:fx="http://javafx.com/fxml/1" fx:controller="de.freakyonline.ucone.FXMLController">
<center>
<TabPane prefHeight="167.0" prefWidth="600.0" tabClosingPolicy="UNAVAILABLE" BorderPane.alignment="CENTER">
<tabs>
<Tab closable="false" text="Players">
<content>
<TableView fx:id="playerTable" editable="true" onContextMenuRequested="#handlePTContextMenuRequest" onInputMethodTextChanged="#handleTextChanged" prefHeight="200.0" prefWidth="200.0">
<columns>
<TableColumn fx:id="nickColumn" onEditCommit="#handlePlayerEditCommit" prefWidth="75.0" text="Nickname" />
<TableColumn fx:id="groupColumn" onEditCommit="#handlePlayerEditCommit" prefWidth="75.0" text="Group" />
<TableColumn fx:id="yearOfBirthColumn" onEditCommit="#handlePlayerEditCommit" prefWidth="94.0" text="Year of Birth" />
<TableColumn fx:id="ageColumn" onEditCommit="#handlePlayerEditCommit" prefWidth="72.0" text="Age" />
<TableColumn fx:id="genderColumn" onEditCommit="#handlePlayerEditCommit" prefWidth="59.0" text="Gender" />
<TableColumn fx:id="lastQuitColumn" onEditCommit="#handlePlayerEditCommit" prefWidth="75.0" text="Last Quit" />
</columns>
<padding>
<Insets bottom="3.0" left="5.0" right="5.0" top="3.0" />
</padding>
</TableView>
</content>
</Tab>
<Tab fx:id="consoleOneTab" closable="false" onSelectionChanged="#handleConsoleOneTabSelected" text="ConsoleOne">
<content>
<VBox prefHeight="200.0" prefWidth="100.0">
<children>
<TextArea fx:id="consoleOneTextArea" editable="false" wrapText="true" VBox.vgrow="ALWAYS" />
<TextField fx:id="consoleOneTextField" alignment="TOP_LEFT" onAction="#handleConsoleOneAction" promptText="type here ..." />
</children>
</VBox>
</content></Tab>
</tabs>
</TabPane>
</center>
<top>
<MenuBar fx:id="mainMenuBar" BorderPane.alignment="CENTER">
<menus>
<Menu mnemonicParsing="false" text="File">
<items>
<MenuItem mnemonicParsing="false" onAction="#handleFileClose" text="Close" />
</items>
</Menu>
<Menu mnemonicParsing="false" text="Help">
<items>
<MenuItem mnemonicParsing="false" onAction="#handleHelpAbout" text="About" />
</items>
</Menu>
</menus>
</MenuBar>
</top>
</BorderPane>

Answer 1

Yes, you can add an Image in your MenuItem without affect on fxml.
First, add FX:ID to your menu-item.
<MenuItem fx:id="close_item" mnemonicParsing="false" onAction="#handleFileClose" text="Close" />
Now use setGraphic() method to add an ImageView in your menu-item.
#FXML MenuItem close_item;
#Override
public void initialize(URL url, ResourceBundle rb) {
ImageView menuIcon = new ImageView(new Image("/path/image.png"));
menuIcon.setFitHeight(20);
menuIcon.setFitWidth(20);
close_item.setGraphic(menuIcon);
//...
//...
}