Question

我在ma UIViewcontroller内部使用包含UITableView的UISearchController，我在viewDidLoad中执行此操作：

    self.searchController = [[UISearchController alloc] initWithSearchResultsController:nil];
    self.searchController.delegate = self;
    self.searchController.searchResultsUpdater = self;
    self.searchController.searchBar.delegate = self;
    self.searchController.dimsBackgroundDuringPresentation = NO;
    self.searchController.hidesNavigationBarDuringPresentation = NO;
    self.definesPresentationContext = NO;

当我按下导航栏中的按钮时，我这样做：

    self.tableView.contentOffset = CGPointMake(0, 0 - self.tableView.contentInset.top);
    self.tableView.tableHeaderView = self.searchController.searchBar;
    [self.searchController.searchBar becomeFirstResponder];

一切正常，但是当我从UIViewController结果中的某一行推出UITableView时UISearchBar停留在那里并显示在另一个视图的内容上，我该怎么办？当我回到查看UITableView

的结果时推送视图并出现时，我会忽略

感谢

编辑：

这是方法didSelectRowAtIndexPath：

的代码

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    [self.tableView deselectRowAtIndexPath:indexPath animated:YES];
    DetailListController *detailList = [[DetailListController alloc] init];
    [self.navigationController pushViewController:detailList animated:YES];
}

Answer 1

将此代码放入viewDidLoad：

self.definesPresentationContext = YES;

Answer 2

当你从DetailListController回到你的视图控制器时（为了安全起见封装在主线程中），你需要调用它：

dispatch_async(dispatch_get_main_queue(), ^{
    self.searchController.active = NO;
});

您也可以在当前视图控制器的viewWillDisappear:中调用它。

Answer 3

尝试使用apple建议的标准方法：

声明属性：

@interface APLMainTableViewController () <UISearchBarDelegate, UISearchControllerDelegate, UISearchResultsUpdating>

@property (nonatomic, strong) UISearchController *searchController;

// our secondary search results table view
@property (nonatomic, strong) APLResultsTableController *resultsTableController;

// for state restoration
@property BOOL searchControllerWasActive;
@property BOOL searchControllerSearchFieldWasFirstResponder;

@end



    - (void)viewDidLoad {
    [super viewDidLoad];

    _resultsTableController = [[APLResultsTableController alloc] init];
    _searchController = [[UISearchController alloc] initWithSearchResultsController:self.resultsTableController];
    self.searchController.searchResultsUpdater = self;
    [self.searchController.searchBar sizeToFit];
    self.tableView.tableHeaderView = self.searchController.searchBar;

    // we want to be the delegate for our filtered table so didSelectRowAtIndexPath is called for both tables
    self.resultsTableController.tableView.delegate = self;
    self.searchController.delegate = self;
    self.searchController.dimsBackgroundDuringPresentation = NO; // default is YES
    self.searchController.searchBar.delegate = self; // so we can monitor text changes + others

    // 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;  // know where you want UISearchController to be displayed
}

- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];

    // restore the searchController's active state
    if (self.searchControllerWasActive) {
        self.searchController.active = self.searchControllerWasActive;
        _searchControllerWasActive = NO;

        if (self.searchControllerSearchFieldWasFirstResponder) {
            [self.searchController.searchBar becomeFirstResponder];
            _searchControllerSearchFieldWasFirstResponder = NO;
        }
    }
}


#pragma mark - UISearchBarDelegate

- (void)searchBarSearchButtonClicked:(UISearchBar *)searchBar {
    [searchBar resignFirstResponder];
}


#pragma mark - UISearchControllerDelegate

// Called after the search controller's search bar has agreed to begin editing or when
// 'active' is set to YES.
// If you choose not to present the controller yourself or do not implement this method,
// a default presentation is performed on your behalf.
//
// Implement this method if the default presentation is not adequate for your purposes.
//
- (void)presentSearchController:(UISearchController *)searchController {

}

- (void)willPresentSearchController:(UISearchController *)searchController {
    // do something before the search controller is presented
}

- (void)didPresentSearchController:(UISearchController *)searchController {
    // do something after the search controller is presented
}

- (void)willDismissSearchController:(UISearchController *)searchController {
    // do something before the search controller is dismissed
}

- (void)didDismissSearchController:(UISearchController *)searchController {
    // do something after the search controller is dismissed
}

以及有趣的部分：使用以下代码从详细视图中恢复时恢复状态

#pragma mark - UIStateRestoration

// we restore several items for state restoration:
//  1) Search controller's active state,
//  2) search text,
//  3) first responder

NSString *const ViewControllerTitleKey = @"ViewControllerTitleKey";
NSString *const SearchControllerIsActiveKey = @"SearchControllerIsActiveKey";
NSString *const SearchBarTextKey = @"SearchBarTextKey";
NSString *const SearchBarIsFirstResponderKey = @"SearchBarIsFirstResponderKey";

- (void)encodeRestorableStateWithCoder:(NSCoder *)coder {
    [super encodeRestorableStateWithCoder:coder];

    // encode the view state so it can be restored later

    // encode the title
    [coder encodeObject:self.title forKey:ViewControllerTitleKey];

    UISearchController *searchController = self.searchController;

    // encode the search controller's active state
    BOOL searchDisplayControllerIsActive = searchController.isActive;
    [coder encodeBool:searchDisplayControllerIsActive forKey:SearchControllerIsActiveKey];

    // encode the first responser status
    if (searchDisplayControllerIsActive) {
        [coder encodeBool:[searchController.searchBar isFirstResponder] forKey:SearchBarIsFirstResponderKey];
    }

    // encode the search bar text
    [coder encodeObject:searchController.searchBar.text forKey:SearchBarTextKey];
}

- (void)decodeRestorableStateWithCoder:(NSCoder *)coder {
    [super decodeRestorableStateWithCoder:coder];

    // restore the title
    self.title = [coder decodeObjectForKey:ViewControllerTitleKey];

    // restore the active state:
    // we can't make the searchController active here since it's not part of the view
    // hierarchy yet, instead we do it in viewWillAppear
    //
    _searchControllerWasActive = [coder decodeBoolForKey:SearchControllerIsActiveKey];

    // restore the first responder status:
    // we can't make the searchController first responder here since it's not part of the view
    // hierarchy yet, instead we do it in viewWillAppear
    //
    _searchControllerSearchFieldWasFirstResponder = [coder decodeBoolForKey:SearchBarIsFirstResponderKey];

    // restore the text in the search field
    self.searchController.searchBar.text = [coder decodeObjectForKey:SearchBarTextKey];
}

@end

Answer 4

在尝试处理相同问题几天之后，意识到这样做的正确方法是使用包含搜索层次结构中所有内容的导航控制器

像这样：

导航1（无导航栏）
（....标签栏，其他任何东西......）
导航2（有导航栏，此导航栏被搜索栏替换
表格控制器

当您按下细节控制器时，将其推入导航1，同时显示其导航栏。

当您在详细信息页面上“返回”

时，这会使搜索堆栈保持不变并准备好工作

UISearchController searchBar在推送viewcontroller时不会消失

4 个答案: