使用UISearchDisplayController显示搜索结果

曾几何时，使用过UISearchBar，当时看到UISearchDisplayController简直是一头雾水，不知道怎么使用。最近的一个app中需要使用该功能，于是写了个Demo探究下。现在做下笔记。

首先往故事板中视图控制器中加入一个Search Bar and Search Display组件：

然后连接Outlets，包括搜索栏和SearchDisplayController：

在ViewController中声明它要遵守以下委托：

@interface ViewController ()  <UISearchBarDelegate,UISearchDisplayDelegate,UITableViewDelegate,UITableViewDataSource>

@property (strong, nonatomic) NSMutableArray *storeResults;

@property (strong, nonatomic) NSMutableArray *results;

- (void)viewDidLoad
{
    [super viewDidLoad];
    
    _srcTableView.dataSource = self;
    _srcTableView.delegate = self;
    
    _searchBar.delegate = self;
    
    _mySearchDisplayController.searchResultsDataSource = self;
    _mySearchDisplayController.searchResultsDelegate = self;
    _mySearchDisplayController.delegate = self;
    
    self.storeResults = [NSMutableArray arrayWithObjects:@"广州", @"北京", @"上海", @"深圳", @"香港", @"广东", @"北师大", @"北大", @"香江", @"香菜", @"北海道", @"惠州", @"东莞", @"杭州", nil];
    self.results = [NSMutableArray array];
}

#pragma mark - UISearchDisplayDelegate

- (BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchString:(NSString *)searchString {
    [self filterContentForSearchText:searchString
                               scope:[_searchBar scopeButtonTitles][_searchBar.selectedScopeButtonIndex]];
    
    return YES;
}

-(BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchScope:(NSInteger)searchOption {
    [self filterContentForSearchText:_searchBar.text
                               scope:_searchBar.scopeButtonTitles[searchOption]];
    
    return YES;
}

-(void)filterContentForSearchText:(NSString*)searchText scope:(NSString*)scope {
    NSMutableArray *tempResults = [NSMutableArray array];
    NSUInteger searchOptions = NSCaseInsensitiveSearch | NSDiacriticInsensitiveSearch;
    
    for (int i = 0; i < _storeResults.count; i++) {
        NSString *storeString = _storeResults[i];
        NSRange storeRange = NSMakeRange(0, storeString.length);
        NSRange foundRange = [storeString rangeOfString:searchText options:searchOptions range:storeRange];
        if (foundRange.length) {
            [tempResults addObject:storeString];
        }
    }
    [self.results removeAllObjects];
    [self.results addObjectsFromArray:tempResults];
}

#pragma mark - UITableViewDataSource

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    if (tableView == _mySearchDisplayController.searchResultsTableView) {
        return _results.count;
    }
    else {
        return _storeResults.count;
    }
}

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return 1;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    static NSString *kCellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:kCellIdentifier];
    if (!cell) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:kCellIdentifier];
    }
    
    if (tableView == _mySearchDisplayController.searchResultsTableView) {
        cell.textLabel.text = _results[indexPath.row];
    }
    else {
        cell.textLabel.text = _storeResults[indexPath.row];
    }
    
    return cell;
}

#pragma mark - UITableViewDelegate

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    if (tableView == _mySearchDisplayController.searchResultsTableView) {
        NSLog(@"%@", _results[indexPath.row]);
    }
    else {
        NSLog(@"%@", _storeResults[indexPath.row]);
    }
}

_mySearchDisplayController.searchResultsTableView的判断。

运行结果如下：