在我的舞台上，我像往常一样在顶部插入一个菜单栏。我想在舞台内的另一个上下文中给出ALT键（连同箭头键）一些逻辑。但每当我按下ALT和箭头时，我也会无意中浏览菜单栏的菜单。
我想避免或更好地完全禁用此助记符行为。 将所有菜单的mnemonicParsing属性设置为false失败。我也试过这种方法但没有成功：
menubar.addEventFilter(KeyEvent.ANY, e -> e.consume());
答案 0 :(得分：3)
当按下 ALT 时，第一个菜单会聚焦，当菜单有焦点时，箭头键会导致它们之间的导航，无论是否按下 ALT 。因此，为了防止出现这种情况，您需要在按下 ALT 时阻止第一个菜单获得焦点。
查看MenuBarSkin班级＆＃39;构造函数源代码，给我们解决方案：
public MenuBarSkin(final MenuBar control) { ... Utils.executeOnceWhenPropertyIsNonNull(control.sceneProperty(), (Scene scene) -> { scene.getAccelerators().put(acceleratorKeyCombo, firstMenuRunnable); // put focus on the first menu when the alt key is pressed scene.addEventHandler(KeyEvent.KEY_PRESSED, e -> { if (e.isAltDown() && !e.isConsumed()) { firstMenuRunnable.run(); } }); }); ... }
正如您已经猜到的那样，解决方案是在 ALT 关闭时使用该事件，但您需要将EventHandler添加到scene而不是menubar：
scene.addEventHandler(KeyEvent.KEY_PRESSED, new EventHandler<KeyEvent>() {
@Override
public void handle(KeyEvent event) {
// your desired behavior
if(event.isAltDown())
event.consume();
}
});
答案 1 :(得分：0)
或者你可以重写MenuBar皮肤。 当ALT键按下，而不是已发布时，Javafx做出了选择（或是一个错误？），重点是MenuBar，是Eclipse，Netbeans中的标准行为.... 此外，当按下或释放ALT_GRAPH键时，不应该关注MenuBar。
这是我建议的补丁。 请注意，只有第一个差异是相关的，最后一个差异只是当一个人无法访问代码时编译的代码。 基本上我已经拆分了＆＃34; firstMenuRunnable＆＃34;在3个函数中
仅在按下F10键时使用firstMenuRunnable
当menuBar具有焦点且ALT键为时，使用deselectOnKeyPressed
当menuBar没有时，使用focusOnFirstMenuOnKeyReleased 焦点和ALT键已发布
因此，人们可以拥有标准行为，允许加速器使用ALT键，而不会被MenuBar 占用。
--- com/sun/javafx/scene/control/skin/MenuBarSkin.java in C:\Program Files (x86)\Java\jdk1.8.0_131\javafx-src.zip
+++ C:\Users\daniel\dev\xxx\Layout\src\com\stimulus\control\MenuBarSkin.java
@@ -372,12 +491,21 @@
scene.getAccelerators().put(acceleratorKeyCombo, firstMenuRunnable);
// put focus on the first menu when the alt key is pressed
+ scene.addEventFilter(KeyEvent.KEY_PRESSED, e -> {
+ altDown = false;
+ });
scene.addEventHandler(KeyEvent.KEY_PRESSED, e -> {
- if (e.isAltDown() && !e.isConsumed()) {
- firstMenuRunnable.run();
+ if (e.isAltDown() && !e.isConsumed() && e.getCode().equals(KeyCode.ALT)) {
+ deselectMenusOnKeyPressed.run();
+ altDown = true;
}
});
+ scene.addEventHandler(KeyEvent.KEY_RELEASED, e -> {
+ if (altDown) {
+ focusOnFirstMenuOnKeyReleased.run();
+ }
});
+ });
ParentTraversalEngine engine = new ParentTraversalEngine(getSkinnable());
engine.addTraverseListener(this);
@@ -434,7 +453,50 @@
}
};
+ private boolean menuDeselectedOnKeyPressed = false;
+ Runnable deselectMenusOnKeyPressed = new Runnable() {
+ public void run() {
+ /*
+ ** check that this menubar's container has contents,
+ ** and that the first item is a MenuButton....
+ ** otherwise the transfer is off!
+ */
+ menuDeselectedOnKeyPressed = false;
+ if (container.getChildren().size() > 0) {
+ if (container.getChildren().get(0) instanceof MenuButton) {
+// container.getChildren().get(0).requestFocus();
+ if (focusedMenuIndex >= 0) {
+ unSelectMenus();
+ menuDeselectedOnKeyPressed = true;
+ }
+ }
+ }
+ }
+ };
+ Runnable focusOnFirstMenuOnKeyReleased = new Runnable() {
+ public void run() {
+ /*
+ ** check that this menubar's container has contents,
+ ** and that the first item is a MenuButton....
+ ** otherwise the transfer is off!
+ */
+ if (container.getChildren().size() > 0) {
+ if (container.getChildren().get(0) instanceof MenuButton) {
+// container.getChildren().get(0).requestFocus();
+ if (focusedMenuIndex == -1 && !menuDeselectedOnKeyPressed) {
+ unSelectMenus();
+ menuModeStart(0);
+ openMenuButton = ((MenuBarButton) container.getChildren().get(0));
+ openMenu = getSkinnable().getMenus().get(0);
+ openMenuButton.setHover();
+ }
+ }
+ }
+ }
+ };
+
private boolean pendingDismiss = false;
// For testing purpose only.
@@ -650,9 +712,23 @@
menuButton.textProperty().bind(menu.textProperty());
menuButton.graphicProperty().bind(menu.graphicProperty());
menuButton.styleProperty().bind(menu.styleProperty());
+ // patch because MenuButtonSkin.AUTOHIDE is private
+ final String AUTOHIDE;
+ {
+ try {
+ Class<?> clazz = MenuButtonSkin.class;
+// System.out.println("fields = " + Arrays.asList(clazz.getDeclaredFields()).toString());
+ Field field = clazz.getDeclaredField("AUTOHIDE");
+ field.setAccessible(true);
+ AUTOHIDE = (String) field.get(this);
+ field.setAccessible(false);
+ } catch (NoSuchFieldException | SecurityException | IllegalAccessException | IllegalArgumentException ex) {
+ throw new UnsupportedOperationException(ex);
+ }
+ }
menuButton.getProperties().addListener((MapChangeListener<Object, Object>) c -> {
- if (c.wasAdded() && MenuButtonSkin.AUTOHIDE.equals(c.getKey())) {
- menuButton.getProperties().remove(MenuButtonSkin.AUTOHIDE);
+ if (c.wasAdded() && AUTOHIDE.equals(c.getKey())) {
+ menuButton.getProperties().remove(AUTOHIDE);
menu.hide();
}
});
以下是我的MenuBar的完整代码：
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package com.stimulus.control;
import javafx.scene.control.Menu;
import javafx.scene.control.MenuBar;
import javafx.scene.control.Skin;
/**
*
* @author daniel
*/
public class CustomMenuBar extends MenuBar {
public CustomMenuBar() {
}
public CustomMenuBar(Menu... menus) {
super(menus);
}
@Override
protected Skin<?> createDefaultSkin() {
return new MenuBarSkin(this) {
};
}
}