iphone - 何时调用 uisearchDisplayController 委托(delegate)方法？

Question

我像这样设置了 searchDisplayController 和 searchBar:

UISearchBar *aSearchBar = [[UISearchBar alloc] initWithFrame:CGRectMake(0, 0, 150, 44)];
self.reportSearchBar = aSearchBar;
_reportSearchBar.tintColor = DARKGRAY_COLOR;
_reportSearchBar.autoresizingMask = UIViewAutoresizingFlexibleLeftMargin;
_reportSearchBar.delegate = self;
[aSearchBar release];

UISearchDisplayController *searchDisplayCtlr = [[UISearchDisplayController alloc] initWithSearchBar:self.reportSearchBar contentsController:self];
self.reportSearchDisplayController = searchDisplayCtlr;
self.reportSearchDisplayController.searchResultsDataSource = self;
self.reportSearchDisplayController.searchResultsDelegate = self;
[searchDisplayCtlr release];

UIBarButtonItem *searchBBI = [[UIBarButtonItem alloc] initWithCustomView:_reportSearchBar];
self.reportSearchBBI = searchBBI;
[searchBBI release];

[self.navigationItem setRightBarButtonItem:_reportSearchBBI animated:NO];

我检查了我的 ViewController 是否符合该类，以防万一:

if ([self conformsToProtocol:@protocol(UISearchDisplayDelegate)]) {
    NSLog(@"conform to search display");
}

我的 ViewController .h 文件有:

<UITableViewDelegate, UITableViewDataSource, UISearchBarDelegate, UISearchDisplayDelegate>

但是，我在

处设置了断点

- (BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchString:(NSString *)searchString {
    [self filterContentForSearchText:searchString];

    return YES;
}

它永远不会到达那里。我实现了 UISearBarDelegate 方法之一，它确实到达了该方法。当我运行 Apple 的示例代码 TableSearch 时，上面复制的 searchDisplayController 委托(delegate)方法确实会运行。因此，对我来说，我尝试将文本放入搜索栏中，但我的应用程序崩溃了，因为过滤列表中没有对象，因为 searchDisplayController 委托(delegate)从未被调用。

想法？谢谢!

Answer 1

我刚刚在苹果引用中看到:

searchController = [[UISearchDisplayController alloc]
                     initWithSearchBar:searchBar contentsController:self];
searchController.delegate = self;
searchController.searchResultsDataSource = self;
searchController.searchResultsDelegate = self;

我在你的代码中没有看到 searchController.delegate = self，这不是必要的吗？

http://developer.apple.com/library/ios/#DOCUMENTATION/UIKit/Reference/UISearchDisplayController_Class/Reference/Reference.html