UISearchbar Parse API - ios

Question

I have a well-functioning search bar. Only one thing that I want to improve is NSTimer. I don`t know why, but when I start typing, it search me results after some delay.It woks perfectly. But I get for every typed letter 1 API each. It mean that if I put into search bar for example Sudan. I get 5 API instead of 1. Could you someone help me?
Thanks
TableViewControllerTOP.h
#interface TableViewControllerTOP : UITableViewController<UISearchDisplayDelegate, UISearchBarDelegate,UIScrollViewDelegate,UITableViewDataSource, UITableViewDelegate>
{
NSTimer *myTimer;
}
#property (strong, nonatomic) IBOutlet UITableView *MainTable;
#property (nonatomic, strong) UISearchBar *searchBar;
#property (nonatomic, strong) UISearchDisplayController *searchController;
#property (nonatomic, strong) NSMutableArray *searchResults;
#property (nonatomic, retain) NSTimer *myTimer;
#property (nonatomic, assign) BOOL isAscending;
TableViewControllerTOP.m
#interface TableViewControllerTOP ()
#property (strong,nonatomic) NSMutableArray *itemss;
#end
#implementation TableViewControllerTOP
#synthesize myTimer;
#synthesize searchBar;
#synthesize searchController;
#synthesize searchResults;
- (id)initWithStyle:(UITableViewStyle)style
{
self = [super initWithStyle:style];
if (self) {
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
self.isAscending = YES;
UIRefreshControl *refreshControl = [[UIRefreshControl alloc] init]; [refreshControl addTarget:self action:#selector(pulltorefresh) forControlEvents:UIControlEventValueChanged];
self.refreshControl = refreshControl;
PFQuery *query = [PFQuery queryWithClassName:#"Countries"];
query.cachePolicy = kPFCachePolicyIgnoreCache;
[query addDescendingOrder:#"createdAt"];
[query setLimit:10];
[query findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {
if (!error) {
NSMutableArray *items = [NSMutableArray array];
for (id obj in objects)
{
[items addObject:obj];
}
self.itemss = items;
NSLog(#"%#", objects);
NSLog(#"%lu", (unsigned long)[objects count]);
[_MainTable reloadData];
} else {
NSLog(#"Error: %# %#", error, [error userInfo]);
}
}];
[self searchitems];
}
-(void)searchitems
{
self.searchBar = [[UISearchBar alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, 44)];
self.tableView.tableHeaderView = self.searchBar;
self.searchController = [[UISearchDisplayController alloc] initWithSearchBar:self.searchBar contentsController:self];
self.searchController.searchResultsDataSource = self;
self.searchController.searchResultsDelegate = self;
self.searchController.delegate = self;
self.searchResults = [NSMutableArray array];
self.tableView.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:#"background.png"]];
[self.navigationController.navigationBar setBarTintColor:[UIColor lightGrayColor]];
}
-(void)filterResults:(NSString *)searchTerm {
myTimer = [NSTimer scheduledTimerWithTimeInterval:3.0
target:self
selector:#selector(queryask)
userInfo:_itemss
repeats:NO];
}
-(void)queryask{
PFQuery *queryCapitalizedString = [PFQuery queryWithClassName:#"Countries"];
[queryCapitalizedString whereKey:#"CountryTitle" containsString:[searchBar.text capitalizedString]];
PFQuery *queryLowerCaseString = [PFQuery queryWithClassName:#"Countries"];
[queryLowerCaseString whereKey:#"CountryTitle" containsString:[searchBar.text lowercaseString]];
PFQuery *querySearchBarString = [PFQuery queryWithClassName:#"Countries"];
[querySearchBarString whereKey:#"CountryTitle" containsString:searchBar.text];
PFQuery *finalQuery = [PFQuery orQueryWithSubqueries:[NSArray arrayWithObjects:queryCapitalizedString,queryLowerCaseString, querySearchBarString,nil]];
[finalQuery findObjectsInBackgroundWithTarget:self selector:#selector(callbackWithResult:error:)];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#pragma mark - Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
// Return the number of sections.
return 1;
}
- (BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchString:(NSString *)searchString {
[self filterResults:searchString];
return YES;
}
- (void)callbackWithResult:(NSArray *)items error:(NSError *)error
{
if(!error) {
[self.searchResults removeAllObjects];
[self.searchResults addObjectsFromArray:items];
[self.searchDisplayController.searchResultsTableView reloadData];
}
}
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
if (tableView == self.tableView) {
return self.itemss.count;
} else {
return self.searchResults.count;
}
}
- (void)searchDisplayController:(UISearchDisplayController *)controller didLoadSearchResultsTableView:(UITableView *)tableView
{
tableView.rowHeight = 70.0f;
}
- ( UITableViewCell * ) tableView : ( UITableView * ) tableView cellForRowAtIndexPath : ( NSIndexPath * ) indexPath
{
static NSString *uniqueIdentifier = #"MainCell";
CustomCell3 *cell = nil;
cell = (CustomCell3 *) [self.tableView dequeueReusableCellWithIdentifier:uniqueIdentifier];
if (!cell) {
NSArray *topLevelObjects = [[NSBundle mainBundle] loadNibNamed:#"MainCell" owner:nil options:nil];
for (id currentObject in topLevelObjects)
{
if([currentObject isKindOfClass:[CustomCell3 class]])
{
cell = (CustomCell3 *)currentObject;
break;
}
}
}
if (tableView == self.tableView) {
cell.MainTitle.text = [[self.itemss objectAtIndex:indexPath.row] objectForKey:#"CountryTitle"];
cell.DescriptTitle.text = [[self.itemss objectAtIndex:indexPath.row] objectForKey:#"DescriptTitle"];
[cell.FlagTitle setImageWithURL:[NSURL URLWithString:[[self.itemss objectAtIndex:indexPath.row] objectForKey:#"ImaURL"]]
placeholderImage:[UIImage imageNamed:#"placeholder.png"]];
cell.backgroundView = [[UIImageView alloc] initWithImage:[ [UIImage imageNamed:#"background.png"] stretchableImageWithLeftCapWidth:0.0 topCapHeight:5.0] ];
cell.selectedBackgroundView = [[UIImageView alloc] initWithImage:[ [UIImage imageNamed:#"background.png"] stretchableImageWithLeftCapWidth:0.0 topCapHeight:5.0] ];
}
if(tableView == self.searchDisplayController.searchResultsTableView) {
PFObject *searchedUser = [self.searchResults objectAtIndex:indexPath.row];
NSString *content = [searchedUser objectForKey:#"CountryTitle"];
NSString *desco = [searchedUser objectForKey:#"DescriptTitle"];
cell.DescriptTitle.text = desco;
cell.MainTitle.text = content;
NSString *image = [searchedUser objectForKey:#"ImaURL"];
[cell.FlagTitle setImageWithURL:[NSURL URLWithString:image]
placeholderImage:[UIImage imageNamed:#"placeholder.png"]];
cell.backgroundView = [[UIImageView alloc] initWithImage:[ [UIImage imageNamed:#"background.png"] stretchableImageWithLeftCapWidth:0.0 topCapHeight:5.0] ];
cell.selectedBackgroundView = [[UIImageView alloc] initWithImage:[ [UIImage imageNamed:#"background.png"] stretchableImageWithLeftCapWidth:0.0 topCapHeight:5.0] ];
}
return cell;
}
#end

Answer 1

For a way to delay the search, take a look at this SO question:
Delay UISearchbar parsing
A good idea could be to combine this with Logan's suggestion. A search should often not be performed until a minimum of characters have been entered, to avoid too broad searches (not much point performing a search for anything containing "s" in many cases, depending on what you are searching).

Answer 2

Perhaps instead of a timer, you could implement a search bar delegate to run a query after some custom logic, perhaps every 3 letters?
- (void) searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText {
if ((searchBar.text.length % 3) == 0) {
[self queryAsk];
}
}
Note: This logic isn't the best, and you might want to explore various parameters for when to search, but I think the concept improves over the timer because it would be more based on input. I think it would give you more control.