[Android] Set LayoutParams Programmatically

* 注意：如果要保險的話，就使用 new LayoutParams(int width, int height), 盡量不要用getLayoutParams()

* TextView margin

lp.setMargins(50, 0, 0, 0); // lp.setMargins(left, top, right, bottom);

* RelativeLayout: toLeftOf, toRightOf, below

lp.addRule(RelativeLayout.RIGHT_OF, R.id.my_view); 

* alignParentLeft, alignParentTop, alignParentRight, alignParentBottom

lp.addRule(RelativeLayout.ALIGN_PARENT_RIGHT);