子控制器未注入主控制器

Question

我有一个BorderPane(与MainController相关联),BorderPane的FXML用于在BorderPane <fx:include>的底部区域包含一个Label(带有控制器StatusBarController).不幸的是,StatusBarController没有注入到MainController类实例中,我无法理解为什么.

main.fxml:包含状态栏的BorderPane

<fx:root type="javafx.scene.layout.BorderPane" fx:id="borderPane" xmlns:fx="http://javafx.com/fxml" fx:controller="com.example.controllers.MainController">
  <bottom>
    <fx:include source="statusbar.fxml" />
  </bottom>
</fx:root>

statusbar.fxml:Label及其关联的控制器

<Label fx:id="statusbar" text="A label simulating a status bar" xmlns:fx="http://javafx.com/fxml" fx:controller="com.example.controllers.StatusBarController" />

带有StatusBarController字段的MainController:

public class MainController
{
    @FXML
    private StatusBarController statusbarController; // PROBLEM HERE: I would expect the StatusBarController to be injected but this does not happen!


    // Implementing Initializable Interface no longer required on JavaFX 2.2 according to
    // http://docs.oracle.com/javafx/2/fxml_get_started/whats_new2.htm
    // (I also tested this, the initialize() method is being called)
    @SuppressWarnings("unused") // only called by the FXMLLoader
    @FXML // This method is called by the FXMLLoader when initialization is complete
    private void initialize() {
        // initialize your logic here: all @FXML variables will have been injected
        assert borderPane != null : "fx:id=\"borderPane\" was not injected: check your FXML file 'main.fxml'.";
        System.out.println("MainController initialize()");

        //statusbarController.setStatusText("Hello from MainController"); // PROBLEM HERE: this fails because statusbarController is not injected as expected
    }
}

并且应用程序的开始:

public void start(Stage primaryStage) 
    {       
        Parent root = null;

        try {
            root = FXMLLoader.load(getClass().getResource("/resources/main.fxml"));
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        primaryStage.setTitle("Demo");
        primaryStage.setScene(new Scene(root, 800, 600));
        primaryStage.show();
    }

我的样本的完整源代码可以在http://codestefan.googlecode.com/svn/trunk/SubcontrollerAccess/上找到.

所以问题是:为什么StatusBarController没有注入到MainController的statusbarController变量中？

谢谢你的提示!

Answer 1

要使用@FXML您必须提供的标签fx:id.

更新你的main.fxml:

<bottom>
    <fx:include fx:id="statusbar" source="statusbar.fxml" />
</bottom>

之后你可以使用你的下一个常量MainController.java:

@FXML
Label statusbar; // node itself
@FXML
private StatusBarController statusbarController; // controller

注意,这statusbarController不是一个部分小写的类名,而是fx:id+ Controllerword.