I'm trying to change the colors of my app, in particular

I'm trying to change the colors of my app, in particular the bar at the top I want that to be black and main background where person logs in to be gray behind my logo.

So I followed instructions and went to colors.xml file and I changed the "wordpress_blue" hex to #000 thinking that this was the blue bar at the top.

Nothing changed.

I then went back and changed it to #000000. Nothing happened.

I then changed hex to #00000000. Nothing happened.

I then changed all the variables' hex codes to #000, #000000, and #00000000 and each time nothing happened although all the hex codes were changed for each variable. Matter of fact, I didn't notice any changes at all although all variables were changed to black.

I thought that maybe it was my system not refreshing the app after each "clean" and so I made a temporary change to the help url in the strings.xml to Google.com and refreshed and cleaned everything. And voila! That worked, so I know that my app is picking up these changes because it picked up that change. And I also swapped an image out and it picked up that change as well.

I just want to know that based on what I'm saying, am I missing something because other than this hiccup, everything else is going to plan. I even uploaded the apk to my phone and it works there like a charm. I just want to have a more suitable color scheme for my brand that totally doesn't look like the Wordpress App which is basically what this app is.

I really like this app and it is quite practical for what I plan to use it for. Just need a little bit more customization options, that's all.

Is anyone else having problems with adjusting the color scheme of their app or can anyone who's knowledgeable of this help point me in right direction?

Thanks!