android popupwindow的实现

View view=getLayoutInflater().inflate(R.layout.layout_popupwindow,null,false);
final PopupWindow popupwindow = new PopupWindow(view, ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT, true);
popupwindow.setTouchable(true);
popupwindow.setTouchInterceptor(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
return false;
}
});
popupwindow.setBackgroundDrawable(new ColorDrawable(0x00000000));
RelativeLayout bottom=(RelativeLayout)findViewById(R.id.bottom);
popupwindow.showAtLocation(bottom, Gravity.BOTTOM,0,bottom.getHeight());