JavaFX Content Rendering & Resizing and Font Bugs In Linux

Siddhesh Rane siddheshrane at
Thu Jan 17 18:55:04 UTC 2019

January 16, 2019 11:31 PM, "Ty Young" <youngty1997 at> wrote:

> How else is percentage based UI sizing besides DoubleBinding(s)? Isn't column restraints just the
> same thing but aligns everything to a column?
> I have to ask(again) as to why minWidth/maxWidth, minHeight/maxHeight, prefWidth/prefHeight aren't
> read only if this is going to be an *always* realistically going to be an issue.

Column constraints don't use any bindings, neither do any other layout panes.
{min,pref,max} width/height are merely hints for a parent to layout the child. They are not the final authority on child size. The actual final size of a child is set by calling Node#resize on it, which is what the parent does during the Parent#layoutChildren call. During this call the parent knows about its own size and can split that space among the children.
A rogue parent could completely ignore these hints and resize the child to whatever it wants.

On your second point, it is only an issue if you use it in the wrong way, without understanding.
You bound the minWidth of a scrollpane's content to 85% of the scrollpane's widthProperty (which is actual width).
When you resize the scrollpane to <85% of its original size, its content still has the old minWidth property which is greater than the current width of the scroll pane. So the scrollpane shows horizontal bar. This is not a bug. widthProperty is supposed to be valid after layout.

Use bindings for size if you want to do some advanced sizing. Like size matching unrelated nodes with different parents to get some visual effect. You could create a custom textarea that binds minWidth to the number of characters in the first line.
I have never had a use case but someone else might.
Use it for cases where there is no mutual dependency or "race condition".

>> I saw your code and I can confirm this is the main cause.
>> If you want a 15-85 % split, you should have used a GridPane with two columns with the given
>> percentage constraints.
> This works for the buttons/scrollpane but what about the subcontent? TableView's scrollbars also
> glitch out in the exact same way.

Set scrollpane to fit to width. Add a gridpane with a single column whose column width is set to 85%. Set gridpane alignment to center. Drop the bindings and your problems will be solved.

> SceneBuilder's lack of UI snapping compared to Netbean's Swing builder makes it incredibly
> difficult to get anything remotely pixel perfect without banging your head against a wall. Separate
> controller classes and FXML annotations everywhere isn't really desirable either. I originally
> entertained the idea of doing it all in FXML only to quickly discard the idea.

If you are talking about snapping like in aligning to other UI elements, then its there and you dont need it with the rought layout. If you mean snapping to pixels, JavaFX has it inbuilt and on by default.


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