How do I use the UISearchBar and UISearchDisplayController

Question

I have an app which displays quite a lot of data in a UITableView. I already added the UISearchBar and UISearchDisplayController in Interface Builder to the UITableView. But I do not know how to use it. If someone could provide a quick solution to this, I would be grateful. I just require it to work as you type to find matches of the search query in the UITableView cells (or from an array).

UPDATE 1: Here's the code from thenumberOfRowsInSection method:

-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section  
{  
if (isSearching) {  
        return [searchResults count];  
    }  
    else {  
        if (section == 0) {  
            return 1;  
        }  
        else if (section == 1) {  
            return [basicQuantities count];  
        }  
        else if (section == 2) {  
            return [physicalQuantities count];  
        }  
    }  

    return nil;  
}

Answer 1

• First add the UISearchDisplayController to your table view
• Then set its delegate.
• Implement the following methods.

Demo Project

In your .h File

    @interface ViewController : UIViewController <UITableViewDelegate, UITableViewDataSource> {

    NSMutableArray *contentList;
    NSMutableArray *filteredContentList;
    BOOL isSearching;
}
@property (strong, nonatomic) IBOutlet UITableView *tblContentList;
@property (strong, nonatomic) IBOutlet UISearchBar *searchBar;
@property (strong, nonatomic) IBOutlet UISearchDisplayController *searchBarController;

In your .m File

Filling the sample data (Optional Only For Demo Purpose)

- (void)viewDidLoad {
    [super viewDidLoad];
    contentList = [[NSMutableArray alloc] initWithObjects:@"iPhone", @"iPod", @"iPod touch", @"iMac", @"Mac Pro", @"iBook",@"MacBook", @"MacBook Pro", @"PowerBook", nil];
    filteredContentList = [[NSMutableArray alloc] init];
}

Now implement the Table View Delegate and Datasource

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {

    // Return the number of sections.
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    // Return the number of rows in the section.
    if (isSearching) {
        return [filteredContentList count];
    }
    else {
        return [contentList count];
    }
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    static NSString *CellIdentifier = @"Cell";

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
    }

    // Configure the cell...
    if (isSearching) {
        cell.textLabel.text = [filteredContentList objectAtIndex:indexPath.row];
    }
    else {
        cell.textLabel.text = [contentList objectAtIndex:indexPath.row];
    }
    return cell;

}

Search Function Responsible For Searching

- (void)searchTableList {
    NSString *searchString = searchBar.text;

    for (NSString *tempStr in contentList) {
        NSComparisonResult result = [tempStr compare:searchString options:(NSCaseInsensitiveSearch|NSDiacriticInsensitiveSearch) range:NSMakeRange(0, [searchString length])];
        if (result == NSOrderedSame) {
            [filteredContentList addObject:tempStr];
        }
    }
}

Search Bar Implementation

- (void)searchBarTextDidBeginEditing:(UISearchBar *)searchBar {
    isSearching = YES;
}

- (void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText {
    NSLog(@"Text change - %d",isSearching);

    //Remove all objects first.
    [filteredContentList removeAllObjects];

    if([searchText length] != 0) {
        isSearching = YES;
        [self searchTableList];
    }
    else {
        isSearching = NO;
    }
    // [self.tblContentList reloadData];
}

- (void)searchBarCancelButtonClicked:(UISearchBar *)searchBar {
    NSLog(@"Cancel clicked");
}

- (void)searchBarSearchButtonClicked:(UISearchBar *)searchBar {
    NSLog(@"Search Clicked");
    [self searchTableList];
}