Navigation bar disappears when typing in UISearchC

问题:

I'm trying to figure out why my whole navigation bar disappears when I start typing in the UISearchController.searchBar It loads properly and animates properly, but I lose the active NavBar when I start typing. Here's the code to load the searchController from viewDidLoad:

    UITableViewController *searchResultsController = [[UITableViewController alloc] initWithStyle:UITableViewStylePlain];

    searchResultsController.tableView.dataSource = self;
    searchResultsController.tableView.delegate = self;
    searchResultsController.tableView.backgroundColor = [UIColor redColor];    

    self.searchController = [[UISearchController alloc] initWithSearchResultsController:searchResultsController];
    self.searchController.delegate = self;
    self.searchController.searchResultsUpdater = self;
    self.searchController.dimsBackgroundDuringPresentation = YES;
    self.searchController.hidesNavigationBarDuringPresentation = NO;

    [self.searchController.searchBar sizeToFit];

    self.tableView.tableHeaderView = self.searchController.searchBar;
    self.definesPresentationContext = NO;

And here's the result after I start typing:

Notice how the table view is there, but it appears to occupy the space of the nav controller and extend downwards into the first section heading. Any ideas?

Thanks.

回答1:

You need to set definesPresentationContext to YES. From apples example:

// Search is now just presenting a view controller. As such, normal view controller
// presentation semantics apply. Namely that presentation will walk up the view controller
// hierarchy until it finds the root view controller or one that defines a presentation context.

self.definesPresentationContext = YES

回答2:

this work for me

self.navigationController.navigationBar.translucent = true;

回答3:

So, I was eventually able to solve this problem with this following init sequence. However, I'm not too sure what I did to make this happen. Kind of busy right now, so I'll just paste this solution and will accept a solution if somebody can pinpoint.

- (void)loadSearchBar
{

    NSLog(@"Loading SearchBar");

    UITableViewController *searchResultsController = [[UITableViewController alloc] initWithStyle:UITableViewStylePlain];
    UITableView *myTv = [[UITableView alloc] initWithFrame:[[UIScreen mainScreen] bounds] style:UITableViewStylePlain];
    searchResultsController.tableView = myTv;
    searchResultsController.tableView.dataSource = self;
    searchResultsController.tableView.delegate = self;
    searchResultsController.tableView.keyboardDismissMode = UIScrollViewKeyboardDismissModeOnDrag;
    searchResultsController.tableView.sectionIndexColor = [UIColor colorWithHexString:linkBlue];

    self.searchResultsController = searchResultsController;

    self.searchController = [[UISearchController alloc] initWithSearchResultsController:searchResultsController];
    self.searchController.delegate = self;
    self.searchController.searchResultsUpdater = self;
    self.searchController.dimsBackgroundDuringPresentation = YES;
    self.searchController.hidesNavigationBarDuringPresentation = NO;
    self.searchController.searchBar.frame = CGRectMake(self.searchController.searchBar.frame.origin.x, self.searchController.searchBar.frame.origin.y, self.searchController.searchBar.frame.size.width, 44.0);

    self.searchBar = self.searchController.searchBar;
    self.searchBar.autocorrectionType = UITextAutocorrectionTypeNo;
    self.searchBar.autocapitalizationType = UITextAutocapitalizationTypeNone;
    self.searchBar.delegate = self;
    self.searchBar.translucent = YES;
    self.tableView.tableHeaderView.layer.zPosition++;

    self.tableView.tableHeaderView = self.searchController.searchBar;
    self.definesPresentationContext = YES;

    //add color to search field
    UIView *subviews = [self.searchBar.subviews lastObject];
    UITextField *textView = (id)[subviews.subviews objectAtIndex:1];

    textView.backgroundColor = [UIColor colorWithHexString:textFieldBlue];

}