Dark Mode support in HTMLTextView

[mhdostal]

This adds dark mode support through CSS elements in the HTML for the TextPopupElement and the HTML view. It also changes the color of the round rect border from .black to .primary, in order to catch light/dark mode changes.

Light Mode:

Dark Mode:

[dfeinzimer]

Everything looks good to me other than the 1 small suggestion above.

[dfeinzimer]

Looks good!

[dfeinzimer]

Turns out black isn't black, but #1C1C1E, when in DarkMode

Nice find!

[mhdostal]

@dfeinzimer Based on team feedback, I've removed the round rect border from the text element.

[dfeinzimer]

Latest changes look good.

This may be better under it's own issue/PR but I noticed that when switching from one popup to another (without closing the panel in-between), the newly selected popup fails to display.

I tried a quick sanity test (showing the latest identify point instead of PopupView) to see if this was an issue with Floating Panel but that worked okay.

Any idea?

[mhdostal]

This may be better under it's own issue/PR but I noticed that when switching from one popup to another (without closing the panel in-between), the newly selected popup fails to display.

@dfeinzimer Thanks. It's an issue with the example and has been reported already. I noticed it a few weeks ago, and fixed it, but I broke it again with recent changes to the example.

[mhdostal]

On some devices, the Dark Mode background color is a dark, dark gray, not black. On other devices, it is true black. Need to dynamically insert the dark mode color into the HTML.

[mhdostal]

On some devices, the Dark Mode background color is a dark, dark gray, not black. On other devices, it is true black. Need to dynamically insert the dark mode color into the HTML.

I'm seeing different background colors on the iPhone 13 mini simulator and the iPad Pro 9.7 simulator. I also see the difference in the "example" list (if you look closely, the background of the list doesn't match the background of the rest of the screen):

The solution is to make the background of the HTML view transparent. This way it will just expose the view background, whether dark or white. The foreground (text) color will remain black or white. This provides the following interesting effect, if you have a slightly (or greatly) transparent background for the floating panel:

[mhdostal]

@dfeinzimer Ok, hopefully one last time.