Toolbar icon tinting on Android

Question

I've noticed that using AppCompat themes, default toolbar icons get tinted by the attribute colorControlNormal in my style.

<style name="MyTheme" parent="Theme.AppCompat">
    <item name="colorControlNormal">@color/yellow</item>
</style>

As you can see above, however, it does not happen with all icons. I provided the "plus" sign, which I got from the official icons, and it does not get tinted (I used the "white" version of the png). From what I have understood from this question, system tints only icons with just an alpha channel. Is this true?

If so: Is there a place where I can find alpha-defined, official material icons? If not - and if Toolbar icons need to be alpha-only to be tinted - how is Google expecting us to use provided icons in a Toolbar?

Somewhere in the SDK I found some icons ending in _alpha.png, and they actually get tinted well. However I need the full set of material icons, and from the official sources I could only find white, grey600 and black ones.

Applying a ColorFilter at runtime would be slightly painful, and my actual Toolbar - with some icons tinted, some others not - looks quite bad.

Answer 1

I see this question is getting some views so I'm going to post an answer for those who don't read the comments.

My conjectures in the question were all wrong and it is not a matter of alpha channels, at least not externally. The fact is simply that, quoting @alanv ,

AppCompat only tints its own icons. For now, you will need to manually tint any icons that you're providing separately from AppCompat.

This might change in the future but also might not. From this answer you can also see the list of icons (they all belong to the internal resource folder of appcompat, so you can't change them) that are automatically tinted and with which color.

Personally I use a colorControlNormal which is black or white (or similar shades), and import the icons with that particular color. Colored icons on a colored background look a little bad. However, another solution I found pleasant is this class on github. You just call MenuColorizer.colorMenu() when you create the menu.