Does wrapping the action code in runLater() help?
b1.setOnAction((ev) -> {
Platform.runLater(() -> {
if (b1.getParent() == cb1) {
...
-andy
From: openjfx-dev <openjfx-dev-r...@openjdk.org> on behalf of John Hendrikx
<john.hendr...@gmail.com>
Date: Thursday, 2022/12/01 at 09:14
To: Nir Lisker <nlis...@gmail.com>
Cc: openjfx-dev@openjdk.org <openjfx-dev@openjdk.org>
Subject: Re: Setting graphics of a Labeled does not show the Label correctly
The mechanism does seem like it is a bit poorly designed, as it is easy to
create inconsistencies.
Luckily it seems that you can't remove a graphic yourself from a Control
(getChildren is protected).
I don't think there is an easy solution though...
I think that once you set a graphic on a Labeled, you need to somehow mark it
as "in use". Normally you could just check parent != null for this, but it is
trickier than that. The Skin ultimately determines if it adds the graphic as
child, which may be delayed or may even be disabled (content display property
is set to showing TEXT only).
Perhaps Skins should always add the graphic and just hide it (visible false,
managed false), but that's going to be hard to enforce.
Marking the graphic as "in use" could be done with:
- a property in `getProperties`
- a new "owner" or "ownedBy" property
- allowing "parent" to be set without adding it to children (probably going to
mess up stuff)
--John
On 01/12/2022 15:21, Nir Lisker wrote:
Technically it doesn't appear elsewhere in the scenegraph, it is the child of
only one label. It's set as the graphics property of 2 labels though. The
mismatch is that being set as a graphics property isn't a 1-to-1 relationship
with being a child of the label.
Something has to be fixed along this chain of inconsistency, I just wasn't sure
where. It seems like the IAE that you mentioned should be thrown, but isn't. I
can write a PR for that. One thing I'm not sure about is: in a situation where
the graphic belongs to a label that is detached from a scene, and that graphic
is set to a label that *is* part of a scene, should an IAE be thrown as well.
Even if the Labeled is part of the Scene, the graphic may not be (depending on
Skin used and on Content Display property for the default skin).
By the way, changing to throwing an IAE is going to cause some new exceptions.
There is a possibility that some VirtualFlow things will break because that
mechanism recycles nodes and re-attaches their properties. Then again, it might
just mean that it was done wrong.
On Thu, Dec 1, 2022 at 3:49 PM John Hendrikx
<john.hendr...@gmail.com<mailto:john.hendr...@gmail.com>> wrote:
Sorry, I meant on the first click already.
--John
On 01/12/2022 14:46, John Hendrikx wrote:
Setting the same Node for multiple graphics is not allowed. Your program
should IMHO throw "IllegalArgumentException" on the 2nd click.
* An optional icon for the Labeled. This can be positioned relative to the
* text by using {@link #setContentDisplay}. The node specified for this
* variable cannot appear elsewhere in the scene graph, otherwise
* the {@code IllegalArgumentException} is thrown. See the class
* description of {@link Node} for more detail.
--John
On 01/12/2022 13:38, Nir Lisker wrote:
That's my point. Currently, a node can serve as the graphics property for
multiple Labels, but will appear only in 1 because it can only have a single
parent in the scenegraph. While this is technically fine, it causes issues like
the one I showed above. I'm not sure if a node is supposed to be able to serve
as multiple graphics (and displayed only in the last Label it was set to?), or
removed from other Labels' graphic properties just like is done for children in
the scenegraph. Personally, I find it confusing that label.getGraphics() will
return a node that isn't shown in that label.
On Thu, Dec 1, 2022 at 2:21 PM John Hendrikx
<john.hendr...@gmail.com<mailto:john.hendr...@gmail.com>> wrote:
Internally the graphics is just a child node, and nodes can't be part of
the scene graph twice (this is done in LabeledSkinBase).
It showing up only once is probably because it is getting removed from
the other labels.
I think things are probably getting out of sync, where the graphics
property may think it still has a certain node as its graphics, but it
is no longer a child of the label.
--John
On 01/12/2022 11:23, Nir Lisker wrote:
> Hi,
>
> Given the following code
>
> var cb1 = new Label("1");
> var cb2 = new Label ("2");
> var b1 = new Button("A");
> cb1.setGraphic(b1);
> b1.setOnAction(e -> {
> if (b1.getParent() == cb1) {
> // cb1.setGraphic(null);
> cb2.setGraphic(b1);
> } else {
> // cb2.setGraphic(null);
> cb1.setGraphic(b1);
> }
> });
>
> Pressing the first button will move it (the graphic) to the second
> label, however, pressing it again will not move it back to the first
> label. It's required to set the graphics to null prior to moving them
> as in the commented lines. This looks like a bug to me. I would think
> that when a graphic is moved, it will appear in its new label
> immediately, like moving a child. Apparently a single node can be the
> graphics for multiple Labeled nodes, but it will appear only in 1. Is
> this intentional?
>
> - Nir
