ios searchDisplayController搜索界面显示“无结果”、"No Results"

“无结果”其实是一个UILabel来的，是searchDisplayController.searchResultsTableView的subview， 实现这个方法就可以隐藏掉：

-(BOOL)searchDisplayController:(UISearchDisplayController )controller shouldReloadTableForSearchString:(NSString )searchString {
dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, 0.001);
dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
for (UIView* v in self.searchDisplayController.searchResultsTableView.subviews) {
if ([v isKindOfClass: [UILabel class]]) {
v.hidden = YES;
break;
}
}
});
return YES;
}