Failed to load AppCompat ActionBar with unknown error.Android Studio 3.1.3

Question

This was my first time using Android studio and I dont know what are those errors mean or what they implyenter image description here

[Render Problem Fa

Answer 1

Missing Constraints in Constraint Layout :-

It means some constraints values are not given like distance from the top ,bottom left and right .Here's a link to solve this problem.

And another link if you want to know more about constraint layout

If you are first time using Android studio then you should start with some simple layouts like linear or relative layout.

Hardcoded text :-

Ths is not an error but a warning. As a general rule, you should never use hardcoded strings in your layout but always use string resources (which means the all strings are stored in one separate file where they are easily changeable for different languages and so on).

To convert a hard coded String to a string ressource:

1:put the curser on the hard coded string

2:press ALT + Enter

3:enter a name for your resource

4:click OK