RFR: 8092102: Labeled: truncated property [v4]

[Marius Hanl]

On Tue, 12 Mar 2024 15:50:21 GMT, Andy Goryachev <angorya at openjdk.org> wrote:

>> modules/javafx.controls/src/main/java/javafx/scene/control/skin/TreeTableCellSkin.java line 133:
>> 
>>> 131:     protected double computePrefWidth(double height, double topInset, double rightInset, double bottomInset,
>>> 132:             double leftInset) {
>>> 133:         if (LabeledHelper.isUseContentWidth() || isDeferToParentForPrefWidth) {
>> 
>> I'm not conviced that this is the correct solution here. 
>> First of all I would keep this PR simple and ONLY add the truncated Property.
>> Second, I would rather want to see if this can be changed without adding some flags which once again will not help application developers that may want to extend something like this.
>> 
>> IMO, the separation of concern is wrong. A Cell should always give back the prefWidth, other callers should think if they want to use the pref width or the table column width.
>> 
>> In order to move this forward, I would like to see only the necessary changes, which is the truncated property. Some tests for it would be good as well.
>
> Thank you for the feedback! 
> 
> The property is being added to Labeled, which happens to be a base class for the cells' skins.  The truncated property therefore must work in all the subclasses, even those where computePrefWidth is hacked via `Properties.DEFER_TO_PARENT_PREF_WIDTH`.
> 
>> Second, I would rather want to see if this can be changed without adding some flags which once again will not help application developers that may want to extend something like this.
> 
> This is a much more difficult task:  First, it needs a careful discussion on which APIs to add, if any (there is a possibility that some people might say that no new APIs are needed as one can always create an instance of Text or Label and use it to get the sizing).  There might be a need to undo the hacks made by the founding father such as `Properties.DEFER_TO_PARENT_PREF_WIDTH`.  I would say all this is out of scope for this PR, as it achieves its goal without introducing the new APIs.
> 
>> IMO, the separation of concern is wrong. A Cell should always give back the prefWidth, other callers should think if they want to use the pref width or the table column width.
> 
> Why cells are controls is slightly beyond me, but who am I to ask?  I would say there should be one control in this picture, and that is TableView (or any other cell-based control) whose job is to size and lay out its various parts.  The current design is different, and it is out of scope for this PR to change the design.
> 
>> In order to move this forward, I would like to see only the necessary changes
> 
> And that 's exactly what you see here - only the necessary changes (that unfortunately include undoing the earlier hacks in cells).
> 
> As for tests - I certainly agree, but that would be a manual test.  The behavior can be verified with the examples in JDK-8205211, I just felt the value of a manual test is rather low.  What I would rather see is an automated test that actually verifies the new property behavior down to a pixel.  Any ideas how to make one?

Okay.

Tests: Well, there are some properties we can test here:
- wrapText = true -> height should be used -> check truncated 
- width changed -> check truncated 
- text changed -> check truncated

-------------

PR Review Comment: https://git.openjdk.org/jfx/pull/1389#discussion_r1526007604