private void addViewByCode(){
View subView = new View(context);
subView.setBackgroundColor(Color.RED);
//subView的宽高
int subViewwidth = 700;
int subViewHeight = 300;
RelativeLayout.LayoutParams relLayoutParams = new RelativeLayout.LayoutParams(subViewwidth, subViewHeight);
//addRule默认是ALIGN_PARENT_LEFT+ALIGN_PARENT_TOP
relLayoutParams.addRule(RelativeLayout.ALIGN_PARENT_LEFT);
relLayoutParams.addRule(RelativeLayout.ALIGN_PARENT_TOP);
int left = 300;
int top = 200;
relLayoutParams.setMargins(left, top, 0, 0);
root_RelativeLayout.addView(subView, relLayoutParams);
}