Action Bar height difference between the attr and runtime

Question

If I do this:

final TypedArray styledAttributes = getBaseContext().getTheme().obtainStyledAttributes(
            new int[]{R.attr.actionBarSize});
    mActionBarHeight = (int) styledAttributes.getDimension(0, 0);
    styledAttributes.recycle();

mActionBarHeight = 144

If I do this:

mActionBarHeight = getSupportActionBar().getHeight() ;

mActionBarHeight = 168

Is there a way of obtaining the same value on the onCreate method of my Activity. If i ran the second option on the onCreate method I get 0, of course.