Some general questions about JavaFX

[Kevin Rushforth]

As noted in the project README [1] on GItHub, JBS [2] is the official 
bug tracker for the OpenJFX project. The GitHub issue tracker is just 
for convenience. Before a bug can be fixed we need a JBS bug. Bugs can 
be filed here [3].

-- Kevin

[1] https://github.com/javafxports/openjdk-jfx#issue-tracking
[2] https://bugs.openjdk.java.net/
[3] http://bugreport.java.com/


On 4/15/2019 7:37 AM, Jason Shattu wrote:
> Hi all,
>
> From a developer who wants to use JavaFX 11+ and as someone that wants 
> to raise bugs, what's the difference between the Oracle Java Bug 
> Database (which is very difficult to use) and the GitHub repo issues 
> list.
>
> I've found 3 annoying bugs with JavaFX in the recent 11+ version (not 
> present in the Java 8 SDK), but i'm finding it hard to find out if 
> these are being worked up or will ever be worked on.
>
> Im thinking of going back to JavaFX 8, but that means downgrading to 
> Java 8 too, unless someone can tell me if there is a JavaFX 8 bundle I 
> can use
>
> The Oracle Java Bug Database seem to just very old bugs and has 
> limited facilities to search.
>
> Guidance anyone?
>
> ------ Original Message ------
> From: "Kevin Rushforth" <kevin.rushforth at oracle.com>
> To: openjfx-dev at openjdk.java.net
> Sent: 15/04/2019 13:27:49
> Subject: Re: JDK-8220272: Found the problem + possible fix
>
>> Hi Thiago,
>>
>> If you are interested in contributing a fix, please see 
>> CONTRIBUTING.md [1] for instructions. Before we can evaluate your 
>> proposed fix, we will need is a signed OCA [2] from you.
>>
>> Thank you.
>>
>> -- Kevin
>>
>> [1] 
>> https://github.com/javafxports/openjdk-jfx/blob/develop/.github/CONTRIBUTING.md
>> [2] http://www.oracle.com/technetwork/community/oca-486395.html
>>
>> On 4/14/2019 5:46 PM, Thiago Milczarek Sayao wrote:
>>> * THE PROBLEM *
>>>
>>> In GlassApplication.cpp, the GDK_FOCUS_CHANGE event gets called from 
>>> the last window to the first on my setup (I suspect "out-of-order" 
>>> on some setups and even occasionally in the expected order). So the 
>>> code to keep the latest enabled window fails (refering to 
>>> WindowStage.java activeWindows) - that's why the "First Window" (on 
>>> the code to reproduce the bug report) shows on top - because openjfx 
>>> thinks it was the latest window. In WindowStage.java:
>>>
>>>      final void handleFocusDisabled() {
>>>          if (activeWindows.isEmpty()) {
>>>              return;
>>>          }
>>>          WindowStage window = activeWindows.get(activeWindows.size() 
>>> - 1); //<-- HERE!!
>>>          window.setIconified(false);
>>>          window.requestToFront();
>>>          window.requestFocus();
>>>      }
>>>
>>> When there is a WINDOW_MODAL this code gets called because the modal 
>>> window disable it's parents (so they do not get events - it's 
>>> correct). So openjfx brings up what it thinks it's the latest window 
>>> - but since the out of order GDK_FOCUS_CHANGE - it's the wrong 
>>> window (activeWindows list has not the correct order).
>>>
>>> The Gtk docs states GDK_FOCUS_CHANGE is true "if the window has 
>>> gained the keyboard focus" which may not be directly correlated to 
>>> openjfx's WindowEvent.FOCUS_GAINED.
>>>
>>> * THE FIX *
>>>
>>> To fix this, WindowEvent.FOCUS_GAINED must be called in order of 
>>> which window is shown (because the window is inserted on 
>>> activeWindows at this event).
>>>
>>> So I have modified glass_window.cpp to immediately call 
>>> WindowEvent.FOCUS_GAINED when showing the window:
>>>
>>> void WindowContextBase::set_visible(bool visible) {
>>>      if (visible) {
>>>          gtk_widget_show_all(gtk_widget);
>>>
>>>          //JDK-8220272 - fire event first because GDK_FOCUS_CHANGE 
>>> is not always in order
>>>          if(jwindow && isEnabled()) {
>>>              mainEnv->CallVoidMethod(jwindow, jWindowNotifyFocus, 
>>> com_sun_glass_events_WindowEvent_FOCUS_GAINED);
>>>          }
>>>      } else {
>>>          gtk_widget_hide(gtk_widget);
>>>          if (jview && is_mouse_entered) {
>>>              is_mouse_entered = false;
>>>              mainEnv->CallVoidMethod(jview, jViewNotifyMouse,
>>>                      com_sun_glass_events_MouseEvent_EXIT,
>>> com_sun_glass_events_MouseEvent_BUTTON_NONE,
>>>                      0, 0,
>>>                      0, 0,
>>>                      0,
>>>                      JNI_FALSE,
>>>                      JNI_FALSE);
>>>              CHECK_JNI_EXCEPTION(mainEnv)
>>>          }
>>>      }
>>> }
>>>
>>> Did some tests and it seems to fix the problem.
>>>
>>> I do not have permission to make a PR, so posting the fix here. Will 
>>> happily do the PR if required.
>>>
>>> Thanks.
>>>
>>