How do I access layout_height from within my custom view?

You can use this:

public CustomView(Context context, AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);

    int[] systemAttrs = {android.R.attr.layout_height};
    TypedArray a = context.obtainStyledAttributes(attrs, systemAttrs);
    int height = a.getDimensionPixelSize(0, ViewGroup.LayoutParams.WRAP_CONTENT);
    a.recycle();
}

that work :)... you need to change "android" for "http://schemas.android.com/apk/res/android"

public CustomView(final Context context, AttributeSet attrs) {
    super(context, attrs);
    String height = attrs.getAttributeValue("http://schemas.android.com/apk/res/android", "layout_height");
    //further logic of your choice..
}