<Swing Dev> [Accessibility]Focus unable to traverse in the menubar

[Frank Ding]

Hi Pavel,
   I think pointing out the special behavior in javadoc makes more 
sense.  Could you please take a look at my draft below?
   http://cr.openjdk.java.net/~dingxmin/8000326/webrev.01
   Note that I think in the sentence "By default, methods of this class 
with return a Component only if it is" it should be "will" not "with", 
shouldn't it?

   Expecting your reply.
Best regards,
Frank

On 10/8/2012 7:47 PM, pavel porvatov wrote:
> Hi Jonathan,
>> Hi Pavel,
>>
>> On 10/02/2012 11:31 PM, Pavel Porvatov wrote:
>>> Hi Jonathan,
>>>> Hi Pavel,
>>>>
>>>> I've filed bug 7198816 for this problem,
>>>>
>>>> Regards, Pavel
>>>> http://bugs.sun.com/view_bug.do?bug_id=7198816
>>> This bug was not ported to jira, so I created another bug:
>>> https://jbs.oracle.com/bugs/browse/JDK-8000326
>>
>> Thanks for porting, but I have trouble with opening that link.
> Sorry, use the following link:
> http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=8000326
>
> but the bug is not available yet... It contains the same description 
> as the original bug.
>
>> Any comments on the patch?
> The fix looks dangerous for me. After the fix the 
> setFocusTraversalKeysEnabled method doesn't work for JMenuBar (when 
> ContainerOrderFocusTraversalPolicy is used) - it ignores this property...
>
> Regards, Pavel
>>
>> best regards
>> Jonathan
>>
>>>
>>> Regards, Pavel
>>>>
>>>> On 11/09/2011 07:25 PM, Pavel Porvatov wrote:
>>>>> Hi Jing,
>>>>>> Thanks Pavel,
>>>>>>
>>>>>>      It seems fine to me, if no other suggestions/opinions, I 
>>>>>> guess we can move on with this?
>>>>> Yes, we can. Could you please file a bug for the problem as well?
>>>>>
>>>>> Thanks, Pavel
>>>>>>
>>>>>> On 2011/11/2 19:58, Pavel Porvatov wrote:
>>>>>>> Hi Jing,
>>>>>>>>
>>>>>>>> Hello Anton,
>>>>>>>>
>>>>>>>>     Thanks for the review. I am still trying to figure out some 
>>>>>>>> real case and provide more detail the customer may fail.
>>>>>>>>     Anyway, I agree we'd better update the java spec to make it 
>>>>>>>> clear for the customers. I'd like to know if anyone can help 
>>>>>>>> with that?
>>>>>>> I'm not sure that javadoc changing is a good decision in this 
>>>>>>> case. ContainerOrderFocusTraversalPolicy is designed for AWT, 
>>>>>>> but I don't know why that policy cannot be used for Swing 
>>>>>>> components as well. I see several problems:
>>>>>>> 1. We cannot change javadoc of 
>>>>>>> ContainerOrderFocusTraversalPolicy because of backward 
>>>>>>> compatibility
>>>>>>> 2. We cannot remove setFocusTraversalKeysEnabled(false) from the 
>>>>>>> JMenuBar#JMenuBar() constructor because of backward compatibility
>>>>>>>
>>>>>>> May be the best decision is to specify, that JMenuBar creates 
>>>>>>> menu with the focusTraversalKeysEnabled = false
>>>>
>>>> Did you mean that for the new menu 
>>>> setFocusTraversalKeysEnabled(false) ? I've tried, but it does not 
>>>> seem to work for this problem.
>>>>
>>>>  if my understanding is incorrect, please help to fix me.
>>>>
>>>>>>>
>>>>>>> Regards, Pavel
>>>>>>>>
>>>>>>>> On 2011/10/12 20:54, Anton Tarasov wrote:
>>>>>>>>> Hi Neil,
>>>>>>>>>
>>>>>>>>> On 10/10/2011 7:01 PM, Neil Richards wrote:
>>>>>>>>>> On Mon, 2011-10-10 at 16:56 +0400, Anton Tarasov wrote:
>>>>>>>>>>> Hi Neil and Jing,
>>>>>>>>>>> I'm afraid that it's wrong to use 
>>>>>>>>>>> ContainerOrderFocusTraversalPolicy
>>>>>>>>>>> for swing components. This policy is designed for AWT.
>>>>>>>>>>> JMenuBar calls setFocusTraversalKeysEnabled(false) in its 
>>>>>>>>>>> ctor which
>>>>>>>>>>> means that it "swallows" focus traversal keys (like 
>>>>>>>>>>> TAB/SHIFT-TAB
>>>>>>>>>>> etc.)
>>>>>>>>>>> and so it can't be a member of a focus traversal chain. Swing's
>>>>>>>>>>> default traversal policy (LayoutFocusTraversalPolicy) excludes
>>>>>>>>>>> JMenuBar
>>>>>>>>>>> from a focus traversal cycle. 
>>>>>>>>>>> ContainerOrderFocusTraversalPolicy is
>>>>>>>>>>> not "aware" about JMenuBar and so it allows it.
>>>>>>>>>>>
>>>>>>>>>>> So, either a default Swing policy should be used, or a 
>>>>>>>>>>> custom policy.
>>>>>>>>>>> At worst, ContainerOrderFocusTraversalPolicy should be 
>>>>>>>>>>> overriden
>>>>>>>>>>> to exclude JMenuBar from a cycle (override its 
>>>>>>>>>>> accept(Component)
>>>>>>>>>>> method).
>>>>
>>>> I agree that backward compatibility should not be broken by the 
>>>> fix, so here's a patch from me for the worst case, could you please 
>>>> help to take a look?
>>>>
>>>> http://cr.openjdk.java.net/~luchsh/7198816/
>>>>
>>>> Thanks
>>>> Jonathan
>>>>
>>>>>>>>>>>
>>>>>>>>>>> Thanks,
>>>>>>>>>>> Anton.
>>>>>>>>>> Hi Anton,
>>>>>>>>>> Thanks for reviewing the suggestion, and for your insights 
>>>>>>>>>> into this
>>>>>>>>>> scenario.
>>>>>>>>>>
>>>>>>>>>> > From the Javadoc, it seems that 
>>>>>>>>>> setFocusTraversalKeysEnabled() is mainly
>>>>>>>>>> concerned with choosing whether focus traversal key presses 
>>>>>>>>>> (normally
>>>>>>>>>> TAB and SHIFT-TAB) are processed "automatically" (when 
>>>>>>>>>> 'true') or are
>>>>>>>>>> delivered to the Component as key events (for the component's 
>>>>>>>>>> code to
>>>>>>>>>> process "manually").
>>>>>>>>>>
>>>>>>>>>> (In the case of JMenuBar, it makes them come through as key 
>>>>>>>>>> events, but
>>>>>>>>>> doesn't do anything special to process these events, which is 
>>>>>>>>>> why they
>>>>>>>>>> get discarded.)
>>>>>>>>>
>>>>>>>>> That is right, though it doesn't directly relate to the issue 
>>>>>>>>> we're talking about =)
>>>>>>>>>
>>>>>>>>>> Your description above, though, seems to suggest that it is 
>>>>>>>>>> generally
>>>>>>>>>> undesirable for the JMenuBar to be given the focus, as all the
>>>>>>>>>> Swing-aware focus traversal policies make a point of not 
>>>>>>>>>> giving focus to
>>>>>>>>>> JMenuBar items.
>>>>>>>>>>
>>>>>>>>>> If this is so, then wouldn't it make sense to call 
>>>>>>>>>> setFocusable(false)
>>>>>>>>>> from its constructor (too), to ensure it doesn't get focus ?
>>>>>>>>>>
>>>>>>>>>> Or, to put it another way, could you explain a little of the 
>>>>>>>>>> reasoning
>>>>>>>>>> or scenario behind why it is desirable for JMenuBar items to be
>>>>>>>>>> generally focusable, even though they aren't focus-traversable ?
>>>>>>>>>>
>>>>>>>>>> I think such an explanation would be really helpful in 
>>>>>>>>>> clearing up my
>>>>>>>>>> confusion on this point.
>>>>>>>>>>
>>>>>>>>>> Thanks, Neil
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Well, I suspect that the core of the problem is that adding 
>>>>>>>>> JMenuBar as JComponent to a swing
>>>>>>>>> container doesn't make much sense. Though it is not directly 
>>>>>>>>> prohibited, doing so may cause
>>>>>>>>> side effects like the one you've discovered. When JMenuBar is 
>>>>>>>>> set properly onto a JFrame its focus
>>>>>>>>> is managed by JRootPane and its focusability just isn't taken 
>>>>>>>>> into account. That's may be the reason
>>>>>>>>> it's not declared unfocusable. Honestly, I can't tell you 
>>>>>>>>> exactly.
>>>>>>>>>
>>>>>>>>> If you do it, you probably won't make any harm, but I 
>>>>>>>>> personally don't think this is a vital fix
>>>>>>>>> (unless you have a good use case of the scenario you've 
>>>>>>>>> provided). Anyway, this is a swing question
>>>>>>>>> (I'm, as an AWT dev member, leaving the decision to swing guys).
>>>>>>>>>
>>>>>>>>> Thanks,
>>>>>>>>> Anton.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>