I want to show fontAwesome icons in my app.
I can show with string type icons like this:
<Text style={{fontFamily: 'fontAwesome'}}></Text>
print icon. Working well.
But I need to show icons with variable like this:
let icon2 = "";
<Text style={{fontFamily: 'fontAwesome'}}>{icon}</Text>
then print to screen 
not icon.
I share with you expo snack link. You can try this easily.
Instead of
let icon2 = "";
you need to define it as;
let icon2 = "\uf0e8";
In javascript, you need to define unicode characters with "\u"
when you assign it to a variable. So it can recognize and parse unicode characters properly.
Edited for your question in your comment;
Your icons are hexadecimal. So we can delete first 3 character from icon. After that, we parse that unicode value as integer and we can convert to
a unicode string by String.fromCharCode
.
icon2 = icon2.substr(3);
icon2 = String.fromCharCode(parseInt(icon2, 16));