android 调出系统menu键

Window window = getWindow();
        try {
            window.addFlags(WindowManager.LayoutParams.class.getField("FLAG_NEEDS_MENU_KEY").getInt(null));
        }
        catch (NoSuchFieldException e) {
// Ignore since this field won't exist in most versions of Android
        }
        catch (IllegalAccessException e) {
            Log.w("====", "Could not access FLAG_NEEDS_MENU_KEY in addLegacyOverflowButton()", e);
        }