RFR: 8344981: [REDO] JDK-6672644 JComboBox still scrolling if switch to another window and return back [v4]

[Prasanta Sadhukhan]

On Fri, 14 Feb 2025 20:20:27 GMT, Damon Nguyen <dnguyen at openjdk.org> wrote:

>> Redo for JComboBox infinite scrolling issue. The issue is that when a scrollbar is clicked and held, if the user switches focus (ex: ALT+TAB) while scrolling, when focused is returned to the scrolling application, the JComboBox will still be scrolling even though nothing it being clicked.
>> 
>> Previously, a KeyboardFocusListener was added to determine the focus. However, there was a memory leak on Windows and Ubuntu. This current implementation uses the current FocusManager and is overall a cleaner, simpler approach.
>> 
>> CI testing is green on all platforms.
>
> Damon Nguyen has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Review suggestions

src/java.desktop/share/classes/javax/swing/plaf/basic/BasicScrollBarUI.java line 1614:

> 1612:             // If scrollbar isn't visible, stop the timer
> 1613:             if (!scrollbar.isShowing()) {
> 1614:                 ((Timer)e.getSource()).stop();

It seems there is duplication of these lines with l1626-1628 which can be placed in a helper method..

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PR Review Comment: https://git.openjdk.org/jdk/pull/23451#discussion_r1957521044