<Swing Dev> [9] Review request for 8074883: Tab key should move to focused button in a button group

[Semyon Sadetsky]

On 11/8/2016 4:00 PM, Sergey Bylokhov wrote:
> On 02.11.16 10:51, Semyon Sadetsky wrote:
>> On 11/1/2016 10:37 PM, Sergey Bylokhov wrote:
>>
>>> On 28.10.16 11:20, Semyon Sadetsky wrote:
>>>>> probably it is possible to change the while loop to something? 
>>>>> just to
>>>>> hide the usage of Enumeration? like
>>>>> Enumiration.asIterator().forEachRemaining()?
>>>> I did not get why. What is wrong with Enumeration?
>>>
>>> It is an old style iterator, and we can hide its usage.
>> Okay. http://cr.openjdk.java.net/~ssadetsky/8074883/webrev.02/
>
> But what about the question to specification, is it the spac below is 
> true when the selected toggle button is disabled?:
>
> 48 * If this toggle button is a member of the {@link ButtonGroup} 
> which has an another focusable toggle button selected, and the focus 
> cause argument denotes window activation or focus traversal action of 
> any direction the result of the method execution is the same as 
> calling {@link Component#requestFocus(FocusEvent.Cause)} on the toggle 
> button selected in the group.
>
> Because the current implementation filter out disabled components(the 
> same question is about invisible, non-displayable), but according to 
> the spec results should be the same like we call the method directly 
> on the selected button.
Probably you missed my previous answer to this question:

If a component is disabled it cannot receive input focus, see 
java.awt.Component#isEnabled specs.  The proposed spec clearly states :

  247      * If this toggle button is a member of the {@link 
ButtonGroup} which has
  248      * an another ***focusable*** toggle button selected, and the 
focus cause argument

in Swing a component may not receive focus if it is disabled, invisible, 
non-displayable...
According to the spec the result will be the same if you call 
Component#requestFocus on ***this*** toggle button.
>
>>>
>>>>>
>>>> If a component is disabled it cannot receive input focus, see
>>>> java.awt.Component#isEnabled specs.  The proposed spec clearly 
>>>> states :
>>>>
>>>>  247      * If this toggle button is a member of the {@link 
>>>> ButtonGroup}
>>>> which has
>>>>  248      * an another ***focusable*** toggle button selected, and the
>>>> focus cause argument
>>>>
>>>>> It seems that the code in getGroupSelection() will focus the first
>>>>> element in the group, but what elements will be focused if we call
>>>>> Component#requestFocus(FocusEvent.Cause) directly for this disabled
>>>>> compoenent? Will the the same(first) element be selected?
>>>> I did find any mentions of "first element" in the proposed spec. 
>>>> Please
>>>> clarify this question.
>>>> According to the proposed spec the case when
>>>> Component#requestFocus(FocusEvent.Cause) is called on disabled 
>>>> component
>>>> will be handled as:
>>>>
>>>>  253      * In all other cases the result of the method is the same as
>>>> calling
>>>>  254      * {@link Component#requestFocus(FocusEvent.Cause)} on this
>>>> toggle button.
>>>
>>> The specification states that the call to
>>> this.requestFocus(FocusEvent.Cause cause);
>>> and the call to
>>> selected.requestFocus(FocusEvent.Cause cause);
>>> produce the same result "If this toggle button is a member of the
>>> {@link ButtonGroup} which has an another focusable toggle button
>>> selected, and the focus cause argument denotes window activation or
>>> focus traversal action of any direction"
>>>
>>> The question was "is that always true if the selected element is
>>> disabled(but focusable)"? I guess that the implementation in the fix
>>> will select the first "this"(the button on which requestFocus() was
>>> called), but in the second case something different will be selected.
>>>
>>>>>> On 10/25/2016 3:14 PM, Alexandr Scherbatiy wrote:
>>>>>>> On 10/19/2016 8:14 PM, Semyon Sadetsky wrote:
>>>>>>>> Hello,
>>>>>>>>
>>>>>>>> Please review fix for JDK9:
>>>>>>>>
>>>>>>>> bug: https://bugs.openjdk.java.net/browse/JDK-8074883
>>>>>>>>
>>>>>>>> webrev: http://cr.openjdk.java.net/~ssadetsky/8074883/webrev.00/
>>>>>>>>
>>>>>>>> To avoid unexpected selection change the selected button of a 
>>>>>>>> button
>>>>>>>> group should always grab focus when focus is transferred form
>>>>>>>> component outside the group to any unselected button inside the
>>>>>>>> group
>>>>>>>> in case of traversal or initial container activation actions.
>>>>>>>   - It is better to pass the cause and boolean focusInWindow
>>>>>>> arguments
>>>>>>> to the getGroupSelection() method to avoid some code duplication 
>>>>>>> like
>>>>>>> switching over the same cause values.
>>>>>>>   - The fix will require a CCC request because it updates a javadoc
>>>>>>> for the publci method.
>>>>>>>
>>>>>>>   Thanks,
>>>>>>>   Alexandr.
>>>>>>>>
>>>>>>>> --Semyon
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>
>>>
>>>
>>
>
>