Accelerator + System MenuBar

[abhinayagarwal]

Background

If the accelerator set on a MenuItem, placed on a MenuBar, is similar to the key events pre-defined on a control, the accelerator shouldn't fire the action of the MenuItem. This can be observed in edit actions of a TextInputControl. When an edit action (like copy, paste etc.) are defined as actions on a MenuItem using KeyEvent(s), these are only fired when the focus is not on a TextInputControl.

Bug

The above mentioned contract is invalid when useSystemMenuBar property of the MenuBar is set to true on a mac. In case of a system menu bar, actions like paste ( CMD+V ) triggers the event for both TextInputControl and MenuItem.

The following example can be used to reproduce the issue on a mac:

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Menu;
import javafx.scene.control.MenuBar;
import javafx.scene.control.MenuItem;
import javafx.scene.control.TextField;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyCodeCombination;
import javafx.scene.input.KeyCombination;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;

public class MenuBarAcceleratorBug extends Application {

    @Override
    public void start(Stage stage) {
        
        TextField textField = new TextField();
        
        MenuItem paste = new MenuItem("Paste");
        paste.setOnAction(e -> textField.paste());
        paste.setAccelerator(new KeyCodeCombination(KeyCode.V, KeyCombination.META_DOWN));
        
        Menu menu = new Menu("Edit");
        menu.getItems().add(paste);
        MenuBar menuBar = new MenuBar(menu);
        menuBar.setUseSystemMenuBar(true);
        
        BorderPane pane = new BorderPane(textField);
        pane.setTop(menuBar);
        
        stage.setScene(new Scene(pane, 300, 200));
        stage.show();
    }
}

[tymur-berezhnoi]

Here is the original issue found https://github.com/gluonhq/scenebuilder/issues/221

So, yes, the bug can be easily reproduced

[johanvos]

The problem is in - (BOOL)performKeyEquivalent:(NSEvent *)theEvent in native-glass/mac/GlassView3D.m That method always return NO, allowing the regular key processing to do its work. In case the action is processed by the application, we should return YES here.

[Siedlerchr]

The bug is still present in javafx15, the only option is to use a workaround and filter out the first event. https://bugs.openjdk.java.net/browse/JDK-8205915