title: How to bind the text of a textarea in fxml to a custom property in the controller?
body: <p>I have a fxml file:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
  
  &lt;?import javafx.scene.control.*?&gt;
  &lt;?import javafx.scene.layout.*?&gt;
  
  &lt;HBox maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity"
        prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1"
        fx:controller="my.AppController"&gt;
      &lt;children&gt;
          &lt;TextArea prefHeight="200.0" prefWidth="200.0" text="${ddd}"/&gt;
      &lt;/children&gt;
  &lt;/HBox&gt;
  </code></pre>
  
  <p>You can see I want to use <code>${ddd}</code> to bind the text of textarea to a custom property from <code>my.AppController</code>.</p>
  
  <p>The code of <code>my.AppController</code>:</p>
  
  <pre><code>public class AppController {
  
    @FXML
    public StringProperty ddd = new SimpleStringProperty("dddddddddd");
  }
  </code></pre>
  
  <p>When I run this javafx application, it doesn't show anything in the textarea, seems it can't bind to the <code>ddd</code> from <code>AppController</code>.</p>
  
  <p>What's the correct way to do it?</p>