<Swing Dev> [9] Review request for 8044371: setOneTouchExpandable functionality of JSplitPane will reduce vertical Scrollbar

[anton nashatyrev]

Hi Alexander,

     this works on the current testcase.
     What makes me more confident is that before the fix JDK-4502121 a 
negative dimension was also possible and the methods you mentioned might 
be called with such values. It seems the class didn't changed 
dramatically since that time.

Thanks!
Anton.

On 25.06.2014 17:12, Alexander Scherbatiy wrote:
>
>  Removing isEmpty variable checking logic leads that some methods 
> (adjustForVSB(...), viewport.toViewCoordinates(...)) could use a 
> rectangle with negative sizes.
>  Do these methods work properly in this case?
>
>  Thanks,
>  Alexandr.
>
> On 6/24/2014 8:31 PM, anton nashatyrev wrote:
>> Hello,
>>     could you please review the following fix:
>>
>> fix: http://cr.openjdk.java.net/~anashaty/8044371/9/webrev.00/ 
>> <http://cr.openjdk.java.net/%7Eanashaty/8044371/9/webrev.00/>
>> bug: https://bugs.openjdk.java.net/browse/JDK-8044371
>>
>> Problem:
>>     After the ScrollPane which is scrolled to the bottom resized to 
>> the width 0 and then back its vertical scroll position changes.
>>
>> Evaluation:
>>     this is the regression from the fix JDK-4502121 
>> <https://bugs.openjdk.java.net/browse/JDK-4502121>.
>>     When the viewport size is 0 the ScrollPaneLayout.layoutContainer 
>> decides not to paint/layout the scrollbars and the viewport height is 
>> calculated with no respect to horizontal scrollbar height. The 
>> viewport height thus becomes larger and its position shifts 25 pixels 
>> (the height of the horisontal scrollbar) up. The expand action 
>> doesn't revert the position which is a normal behavior.
>>
>> Fix:
>>     modify the fix for JDK-4502121 
>> <https://bugs.openjdk.java.net/browse/JDK-4502121>, so it still 
>> solves the original problem, but doesn't add the unwanted behavior: 
>> the layout should take into account the scrollbars even if the size 
>> of the scrollpane is 0.
>>
>> Thanks!
>> Anton.
>