Hi folks. A couple of weeks ago I took some time to review the Ambiance theme. I concentrated on the theming of GTK controls, rather than Shell/Firefox/LibreOffice (though those are important too).
1. Orange wash
Orange gets a bit tiresome over large areas. And when it is used as a transparent tint on a grey area, it almost appears pink.
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Perhaps the focus appearance could avoid using a tinted background.
2. Header bar button height
Buttons in the header bar are taller than they are just about everywhere else.
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I’m glad to see that this is one of the things improved in Ambiance-RW!
3. Header bar button focus
We used to have orange commit buttons — and Ambiance in Qt unfortunately still does. The problem is that it looks quite similar to red for danger (while really dangerous buttons are often left plain).
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Unfortunately, Gnome has copied iOS in moving commit buttons to the header bar. This layout saves space on small-screen iPhones. But on the screens that Gnome runs on, it makes these buttons very difficult to find. It goes against the whole flow of the window contents, and it’s inconsistent with Windows, macOS, and popular non-Gnome apps like LibreOffice.
We can’t restore the button position in a theme, because it’s hard-coded into individual apps. The next best thing, I thought, would be to use a bright color to make the positive buttons a bit easier to find. So I suggested using the Suru green.
However, this introduces a new problem: when the button is focused, the orange focus ring is hard to see between the green button and the dark grey background.
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I’m not sure what to do about this. Just making the focus ring thicker would help, but the colors would clash. Perhaps there’s a different way to make header bar buttons more visible, a style that can also be used for buttons outside header bars, and one that makes focus more visible.
4. Link mouseover
When you hover over a link, it changes to look like a button. This is distracting and unnecessary (Adwaita doesn’t do it).
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5. Checkbox and radio button size
Checkboxes and radio buttons seem to be much smaller, compared with other controls, than they are in other toolkits.
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6. Checkbox focus
If you focus a checkbox, that highlights its label, and often highlights a large empty space next to the label — but it doesn’t highlight the actual checkbox! Adwaita’s dotted focus rings are very Windows-95-ish, but at least they enclose the checkbox.
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7. Radio button focus
If you focus a radio button, that highlights … nothing at all. Oops.
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8. Checkboxes vs. radio buttons
The rounded corners of checkboxes makes them look needlessly similar to radio buttons. There’s no confusion when they’re checked — but when they’re unchecked, or in their mixed value, they’re harder to distinguish. This is a case where rounded corners are a bad idea.
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9. Selection color in text fields, combo boxes, and lists
When you move focus away from a text field, combo box, or list, any selection remains bright orange. This is distracting, and makes it harder to see where the focus is. On other platforms, selections in unfocused controls are usually grey. (In this case, Adwaita has the same problem.)
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10. Text field error state
When a text field is in the error state, it becomes solid red. This is excessive. (Unfortunately I don’t have a screenshot of this.)
11. Step field background
The grey background of a step field’s buttons bleeds into the field itself. (You may need to tilt your screen to notice this.)
12. Incomplete focus rings
When focus is on a combo box’s text field, a combo box’s button, a text field with a clear button, the clear button itself, or a button or menubutton that touches another control, the focus ring covers only two or three sides of the control, rather than all four.
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13. Radio menus vs. menubuttons
A radio menu (the kind that, when closed, shows the one currently-chosen item) looks identical to a menubutton (the kind that, when closed, shows a title). Things that behave differently should look different.
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Other platforms solve this by giving a radio menu a double triangle, rather than a single triangle. (This also hints that the menu will open both upward and downward, rather than just downward.)
14. Indeterminate progress bars
If you glance at it at the wrong moment, an indeterminate progress bar looks identical to a determinate progress bar. Things that behave differently should look different.
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Other platforms use a barberpole pattern or pulsing color to distinguish indeterminate progress bars. This might not be fixable in a GTK theme, though.
15. Sliders
If you mouse down on a slider thumb, it doesn’t go slightly darker like a button does.
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Separately, if you mouse down on a slider thumb and don’t move for a couple of seconds, the thumb weirdly gets smaller. Adwaita doesn’t have this problem (it does something differently weird).
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Some of these glitches might be baked into GTK, not fixable in a theme alone.