问题

所以我试图让我的JavaFX应用程序在按下CTRL + Alt + D时可见（我正在使用[jkeymaster][1]）。但每次我在我的HotKeyListener中写入Stage.show();时，我都会得到“线程中的异常“AWT-EventQueue-0”java.lang.IllegalStateException: Not on FX application thread; currentThread = AWT-EventQueue-0（第7行）”（我还测试过在我的热键监听器中和监听器外显示文件选择器，如果我做第二件事，就不会出现错误）。而且，如果我只在我的热键监听器中放入“System.out.println("Test")”而没有其他的东西，它只会输出它，我不会出现错误。

```java
public class Main extends Application {

    public static Stage s;

    @Override
    public void start(Stage stage) throws Exception {
        Scene scene = new Scene(FXMLLoader.load(getClass().getResource("Main.fxml")));
        stage.setScene(scene);
        stage.setTitle("Test");
        stage.setResizable(false);
        s = stage;

    }
}

Controller:

public class Controller {

    public void initialize() {
        Provider provider = Provider.getCurrentProvider(true);
        openSaveDialog(Main.s); //没有错误
        HotKeyListener l = hotKey -> {
            Main.s.show();
            openSaveDialog(Main.s);
            // 返回错误
        };
        provider.register(KeyStroke.getKeyStroke("control alt D"), l);
    }

    public File openSaveDialog(Stage s) {
        FileChooser chooser = new FileChooser();
        chooser.setTitle("Select the output");
        return chooser.showSaveDialog(s);
    }
}

<details>
<summary>英文:</summary>

So I&#39;m trying to make my JavaFX Application visible, if I press CTRL + Alt + D (I&#39;m using [jkeymaster][1]). But everytime I write Stage.show(); in my HotKeyListener I get `Exception in thread &quot;AWT-EventQueue-0&quot; java.lang.IllegalStateException: Not on FX application thread; currentThread = AWT-EventQueue-0 (line 7)` (I also tested to show a file chooser in my hot key listener and outside of the listener and if I do the second thing I get no error). And also if I just put `System.out.println(&quot;Test&quot;)` in my hot key listener without the other things it just outputs it and I get no error

    public class Main extends Application {

    public static Stage s;

    @Override
    public void start(Stage stage) throws Exception {
        Scene scene = new Scene(FXMLLoader.load(getClass().getResource(&quot;Main.fxml&quot;)));
        stage.setScene(scene);
        stage.setTitle(&quot;Test&quot;);
        stage.setResizable(false);
        s = stage;

    }
}

Controller:

        public class Controller {
    
        public void initialize() {
            Provider provider = Provider.getCurrentProvider(true);
            openSaveDialog(Main.s); //No error
            HotKeyListener l = hotKey -&gt; {
                Main.s.show();
                openSaveDialog(Main.s);
                //Returns an error
            };
            provider.register(KeyStroke.getKeyStroke(&quot;control alt D&quot;), l);
        }
    
        public File openSaveDialog(Stage s) {
            FileChooser chooser = new FileChooser();
            chooser.setTitle(&quot;Select the output&quot;);
            return chooser.showSaveDialog(s);
        }
    }


  [1]: https://github.com/tulskiy/jkeymaster

</details>


# 答案1
**得分**: 1

如果您尝试将`HotKeyListener`的内容包装在对`Platform.runLater()`的调用中，这应该可以解决问题。因为您正在修改JavaFX场景图，所以这项工作必须在应用程序线程上完成。

```java
HotKeyListener l = hotKey -> {
    Platform.runLater(() -> {
        Main.s.show();
        openSaveDialog(Main.s);
    });
};

不过，与其使用AWT HotKeyListener，您真的应该通过JavaFX的事件来注册一个键盘监听器。那样的话，您就不需要调用Platform.runLater()了。

HotKeyListener l = hotKey -> {
    Platform.runLater(() -> {
        Main.s.show();
        openSaveDialog(Main.s);
    });
};