I think to add a comment to this line like the following:
``` java
// Typeface.createFromAsset doesn't work in the layout editor.
if (isInEditMode()) {
return;
}
TypedArray values = context.obtainStyledAttributes(attrs, R.styleable.RobotoTextView);
int typefaceValue = values.getInt(R.styleable.RobotoTextView_typeface, 0);
values.recycle();

setTypeface(obtaintTypeface(context, typefaceValue));
```