Thank you to My Best Teacher @MohamedTamer for teaching me so many things.
Thank you to My Best Friend @vknow360 for helping me.
And Also Thanks to @WatermelonIce And @Kumaraswamy for helping me too.
Thank you very much for the suggestion @Taifun, actually I want to make it as you say, but I don't know why I really like hex color and I think hex color is not too complicated like RGB,
and actually I don't know how to use the App Inventor RGB code in my extension.
So can you give me a simple code that can use RGB App inventor?
it doesn't really matter what you prefer personally...
App Inventor already uses the color blocks... this was a design descision some years ago by the App Inventor team... everybody is used to work with the color blocks... and to be compatible with the color blocks therefore is the way to go...
just look at the App Inventor sources... you will find examples how to do the conversion...
and if you have questions, start a new thread in the Open Source Development category
thank you