Fix Text Color to Meet WCAG 2.0 Contrast Minimum

[sstream17]

Currently the text color is not possible to see for some colors and themes.

For example, when the color is too bright, the text will appear white and it is very hard to read.

This change sets the project to follow the WCAG 2.0 Contrast Minimum when setting text colors.

The same color now sets the text to be black.

I have followed the guideline recommendation of setting the ratio to be 4.5:1.

[Serubin]

This looks awesome. I wasn't able to reproduce the issue with that particular green color, but I've definitely seen this be an issue.

I added a couple of nitpicks - should be good to merge once we resolve those.

Thanks for submitting this!

[klinker24]

Sorry it took awhile for me to look at this, but I do have some thoughts around it. I am also holding off deploying this until I can get Android prepared with the same changes.

While I definitely agree that improvements can and should be made in this area, I honestly think that 4.5:1 is too much. For example, it marks this color as needing dark text, which I don't agree with and think that just looks bad:

In my opinion, using 0.3 is a better number than 0.233. That will, at least, make this message use white text. Obviously this is completely opinion based, but it is my name on the app listing and me that has to deal with people complaining about changes 🙈frankly, I will get complaints about a UI change like this. This change is pretty drastic and seems to affect tons of different colors/conversations

[sstream17]

In my opinion, using 0.3 is a better number than 0.233

I agree! Feel free to change the value to anything you prefer. I set the initial ratio to 4.5:1 because that is what the guideline recommended. I did notice that many reds displayed black text using that ratio and I did think it was more difficult to see them.

[Serubin]

Apologies - jumped the gun on the merge

[klinker24]

No worries, usually I am much faster at getting to PRs. I was just slower on this one