How do I cover the “no results” text in UISearchDisplayController's searchResultTableView?

Question

I don't want to show the "no results" text while my server is processing a search query.

I figured out the exact coordinates of the table cell that contains the label and attempted to cover it.

self.noResultsCoverView = [[[UIView alloc] initWithFrame:CGRectMake(
    0.0, 
    44.0, 
    320.0, 
    43.0
)] autorelease];
self.noResultsCoverView.backgroundColor = [UIColor whiteColor];
[self.searchDisplayController.searchResultsTableView addSubview:self.noResultsCoverView];

To my chagrin, my cover was above the table view, but below the label. I need the cover to be above the label. searchResultsTableView::bringSubviewToFront didn't work, which makes me believe that the label isn't a child of the searchResultsTableView at all.

BTW, this Stack Overflow answer doesn't quite work for me. It works on the very first search, but flashes a weird black cover on subsequent searches.

Answer 1

The easiest way to work around this is to return 1 in numberOfRowsInSection while the query is in progress and leave the dummy cell empty or set its hidden property to YES so it is not visible.

Answer 2

this should do the work properly. The code to return at least one cell:

BOOL ivarNoResults; // put this somewhere in @interface or at top of @implementation
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    if (tableView == self.searchDisplayController.searchResultsTableView) {
        if (filteredList.count == 0) {
            ivarNoResults = YES;
            return 1;
        } else {
            ivarNoResults = NO;
            return [filteredList count];
        }
    }
    // {…}
    // return the unfiltered array count
}

and for "showing" the clean cell:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath 
{
    if (tableView == self.searchDisplayController.searchResultsTableView && ivarNoResults) {
        static NSString *cleanCellIdent = @"cleanCell";
        UITableViewCell *ccell = [tableView dequeueReusableCellWithIdentifier:cleanCellIdent];
        if (ccell == nil) {
            ccell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cleanCellIdent] autorelease];
            ccell.userInteractionEnabled = NO;
        }
        return ccell;
    }

    // {…}
}

Answer 3

Try this it worked for me

In the UISearchDisplayController delegate do this:=

- (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]] && 
                [[(UILabel*)v text] isEqualToString:@"No Results"]) {
                [(UILabel*)v setText:@""];
                break;
            }
        }
    });
    return YES;
}

Answer 4

You need to realize that when you have a UISearchDisplayController, and the search bar is active, the UITableView argument passed into your UITableView data source and delegate methods is in fact NOT your tableView object, but a tableView managed by the UISearchDisplayController, intended to display "live" search results (perhaps results filtered from your main data source, for example).

You can easily detect this in code, and then return the appropriate result from the delegate/data source method, depending on which tableView object is asking.

For example:

- (NSInteger)tableView:(UITableView *)tv numberOfRowsInSection:(NSInteger)section
{
    if (tv == self.searchDisplayController.searchResultsTableView) {
        // return the number of rows in section for the visible search results.
        // return a non-zero value to suppress "No results"
    } else {
        // return the number of rows in section for your main data source
    }
}

The point is that your data source and delegate methods are serving two tables, and you can (and should) check for which table is asking for data or delegation.

By the way, the "No results" is (I believe) provided by a background image which the UISearchDisplayController displays when the delegate says there are no rows... You are not seeing a 2-row table, the first blank and the second with text "No results". At least, that's what I think is happening there.