RFR: 8310072: JComboBox/DisabledComboBoxFontTestAuto: Enabled and disabled ComboBox does not match in these LAFs: GTK+ [v3]

[Damon Nguyen]

On Wed, 17 Apr 2024 09:55:43 GMT, Abhishek Kumar <abhiscxk at openjdk.org> wrote:

> > As far as I understand the test creates two enabled-JComboBox, then disables both, and then compares the disabled and enabled images. Why there are some differences in sizes and colors?
> 
> Difference in size is specific to LAFs like in case on Metal and Motif the sizes are same but in Nimbus and GTK it differs in size. For Nimbus when DefaultListCellRenderer is used the width is 2px more than when SynthComboBoxRenderer is used. This is due to the difference in Inset values. In case of DefaultListCellRenderer the Insets value (left and right) are 1 px more than the insets value for SynthComboBoxRenderer.
> 
> Similarly in GTK LAF also the insets values are different in DefaultListCellRenderer and SynthComboBoxRenderer.
> 
> Color difference is only in the background color for Windows LAF which is slightly different.

This sounds about right. I looked into this difference briefly in my original fix, and checked the insets, bounds, and borders. Now that you mention it, I remember it was the insets that differed between the two renderers. Didn't seem related to the issue/fix and may be intended, so I left it as is and modified my test to use a midline scan to compare the pixel colors between the two comboboxes.

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

PR Comment: https://git.openjdk.org/jdk/pull/18644#issuecomment-2064335397