FXMLLoader getController 返回 NULL? [英] FXMLLoader getController returns NULL?

问题描述

我的主应用程序类可以很好地执行以下操作:

I have the main application class that does the following just fine:

   @Override
   public void start(Stage primaryStage) {
      try {
         FXMLLoader loader = new FXMLLoader(getClass().getResource(
               "RecordScreen.fxml"));
         Parent root = (Parent) loader.load();
         Scene newScene = new Scene(root);
         Stage newStage = new Stage();
         newStage.setScene(newScene);
         newStage.show();
      } catch (Exception e) {
         e.printStackTrace();
      }
   }

它启动一个显示人物的表格视图.我选择一个人，点击编辑按钮，然后尝试启动一个窗口，让我编辑他们.

It launches a table view that displays people. I select a person, hit the edit button, and try to launch a window that will let me edit them.

   @FXML
   public void editPerson() {
      try {
         FXMLLoader loader = new FXMLLoader(getClass().getResource(
               "PersonEditor.fxml"));
         PersonEditorCtrl ctrl = loader.getController();
         ctrl.init(table.getSelectionModel().getSelectedItem());
         Parent root = (Parent) loader.load();
         Scene newScene = new Scene(root);
         Stage newStage = new Stage();
         newStage.setScene(newScene);
         newStage.show();
      } catch (Exception e) {
         e.printStackTrace();
      }
   }

问题是，getController 返回 null.过去 2 周我一直遵循这种模式，没有任何问题.我现在做错了什么?这些无法追踪的错误正在加剧！！！

The problem is, getController is returning null. I have been following this pattern for the past 2 weeks with no problems whatsoever. What am I doing wrong now? These untraceable bugs are aggravating!!!

这是我的两个 fxml:

Here are my two fxmls:

带有 tableview 的屏幕:

The screen with tableview:

<AnchorPane xmlns:fx="http://javafx.com/fxml/1" xmlns="http://javafx.com/javafx/2.2" fx:controller="application.RecordsCtrl">
  <!-- TODO Add Nodes -->
  <children>
    <VBox id="VBox" alignment="CENTER" spacing="0.0" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="0.0">
      <children>
        <TableView fx:id="table" prefHeight="-1.0" prefWidth="-1.0">
          <columns>
            <TableColumn prefWidth="75.0" text="Name" fx:id="nameCol" />
            <TableColumn prefWidth="75.0" text="Age" fx:id="ageCol" />
          </columns>
        </TableView>
        <Button mnemonicParsing="false" onAction="#editPerson" text="Edit" />
      </children>
    </VBox>
  </children>
</AnchorPane>

个人

<AnchorPane xmlns:fx="http://javafx.com/fxml/1" xmlns="http://javafx.com/javafx/2.2" fx:controller="application.PersonEditorCtrl">
  <!-- TODO Add Nodes -->
  <children>
    <VBox layoutX="0.0" layoutY="0.0" prefHeight="-1.0" prefWidth="-1.0">
      <children>
        <TextField fx:id="nameField" prefWidth="200.0" />
        <TextField fx:id="ageField" prefWidth="200.0" />
        <Button mnemonicParsing="false" text="Button" />
      </children>
    </VBox>
  </children>
</AnchorPane>

推荐答案

改变这个

@FXML
   public void editPerson() {
      try {
         FXMLLoader loader = new FXMLLoader(getClass().getResource(
               "PersonEditor.fxml"));
         PersonEditorCtrl ctrl = loader.getController();
         ctrl.init(table.getSelectionModel().getSelectedItem());
         Parent root = (Parent) loader.load();
         Scene newScene = new Scene(root);
         Stage newStage = new Stage();
         newStage.setScene(newScene);
         newStage.show();
      } catch (Exception e) {
         e.printStackTrace();
      }
   }

为此:

@FXML
   public void editPerson() {
      try {
         FXMLLoader loader = new FXMLLoader(getClass().getResource(
               "PersonEditor.fxml"));
         Parent root = (Parent) loader.load();
         PersonEditorCtrl ctrl = loader.getController();
         ctrl.init(table.getSelectionModel().getSelectedItem());

         Scene newScene = new Scene(root);
         Stage newStage = new Stage();
         newStage.setScene(newScene);
         newStage.show();
      } catch (Exception e) {
         e.printStackTrace();
      }
   }

你首先必须运行 loader.load() 然后你才能得到控制器.

You first have to run loader.load() then you can get the Controller.

帕特里克

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