UIView*titleView = [[UIViewalloc]initWithFrame:CGRectMake(0,0,winWidth-87,30)];
_searchBar= [[UISearchBaralloc]initWithFrame:CGRectMake(0,0,winWidth-87,30)];
_searchBar.layer.cornerRadius=16;
_searchBar.layer.masksToBounds=YES;
//_searchBar.layer.borderWidth=1;
//_searchBar.layer.borderColor= [UIColoryellowColor].CGColor;
_searchBar.placeholder=@"关键字查询";
[titleViewaddSubview:_searchBar];
self.navigationItem.titleView= titleView;