RFR: 8255572: Axis does not compute preferred height properly when autoRanging is off [v6]

[Jonathan Vusich]

On Mon, 26 Apr 2021 21:06:41 GMT, Kevin Rushforth <kcr at openjdk.org> wrote:

>> Well, it's complicated. The algorithm that calculates the required space for the tick labels does not take into account the tick label rotation. I did not look into adding this at this time because that opens up a lot of other potential pathways that seem broader in scope. With these changes, if the application detects that there is not enough space to display the text at the current rotation (which is assumed to be either 90 or 0 degrees), we rotate it by 90 degrees and remeasure. If that second remeasuring shows that the tick labels can be fully displayed at that rotation, the tick label rotation is overwritten to either 0 or 90 degrees. Theoretically if a user defines a set tick label rotation, it can be overwritten under these circumstances. However, I think this is reasonable given that when `autoRanging` is disabled a number of other properties are also overwritten in a similar manner.
>
> Yeah, it is complicated, and I agree doesn't work entirely correctly today, but this change breaks setting the axis tick label rotation completely, even in case where will fit without forcing the rotation to 90.
> 
> To reproduce this problem, run the Ensemble8 app with your fix, select the Bar Chart sample, and attempt to change the X axis `tickLabelRotation`, either using the slider or entering a number in the text field. You will be unable to change the value since the code you added will overwrite it.
> 
> If you run it without your fix, you can change the X axis `tickLabelRotation`. It won't take effect right away (that's a bug), but if you uncheck and then recheck `tickLabelsVisible` it will re-layout the chart and the axis labels will be drawn rotated.
> 
> With auto-ranging selected, if you run with your fix, you can change the axis, but it won't actually do anything, even in the case where the label fits.
> 
> Without your fix, you can rotate the labels with the slider just fine.
> 
> So while I agree that improving the situation when a rotation is set could be done as a follow-up bug, we need a solution that won't break existing use cases that are working.

@kevinrushforth Thank you for pointing this out, I was not aware of the Ensemble8 app that provided a testbed for this functionality. I will dig into this again and figure out a better solution. 

On a somewhat unrelated note to this PR, are there any instructions for how to get the JavaFX repository set up in an IDE? I have had a terrible time dealing with compile warnings in my IntelliJ IDE even though I can run everything successfully through Gradle on the command line.

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PR: https://git.openjdk.java.net/jfx/pull/342