wifi设置页面的源码是WiFiSettings.java 类，该类实际就是一个PreferenceFragment的子类，下面是源码，工作原理在注释中说明
FrameLayout.LayoutParams returnLayoutparams = new FrameLayout.
LayoutParams(LayoutParams.MATCH_PARENT, );
returnLayoutparams.gravity = Gravity.BOTTOM|Gravity.RIGHT;
RelativeLayout returnLayout = new RelativeLayout(getActivity());
returnLayout.setPadding(, , , );
returnLayout.setBackgroundResource(android.R.color.transparent);