UIsearchBar iOS11 像之前的版本那样没有内容居

@property(nonatomic,assign)CGFloatwidth;

//判断版本

if(@available(iOS11.0, *)){

UITextField *textField = [self.searchBar valueForKey:@"searchField"];

[textField sizeToFit];

//记录一下这个时候的宽度

_width= textField.frame.size.width;

[_searchBar setPositionAdjustment:UIOffsetMake((_searchBar.width-_width)/2.0,0)forSearchBarIcon:UISearchBarIconSearch];

}

然后在代理方法 searchBarTextDidBeginEditing:(UISearchBar*)searchBar 调整位置

if(@available(iOS11.0, *)){

[_searchBar setPositionAdjustment:UIOffsetMake(0,0)forSearchBarIcon:UISearchBarIconSearch];

}

结束的方法  searchBarTextDidEndEditing:(UISearchBar*)searchBar 判断是否有内容

if(@available(iOS11.0, *)){

if(!_searchBar.text.length) {

[_searchBar setPositionAdjustment:UIOffsetMake((_searchBar.width-_width)/2.0,0) forSearchBarIcon:UISearchBarIconSearch];

}

}