如何使用目标c实现UISearchController [英] How to implement UISearchController with objective c

问题描述

我有一个用objective-c编写的现有应用程序，带有表格视图。

I have an existing app, written in objective-c, with a table view.

我现在正试图回到这个应用程序并添加一个搜索栏到目前为止。

I am now trying to go back to this app and add a search bar to the table.

问题是现在有了新的 UISearchController 协议，似乎很少关于如何在objective-c中实现这一点的在线信息 - 我能找到的所有教程和示例都是针对Swift的。

The problem is that now there is the new UISearchController protocol, there seems to be very little information online in how to implement this within objective-c - all tutorials and examples that I can find are all for Swift.

我已将代理添加到.h文件中：

I have added the delegates to the .h file:

UISearchBarDelegate, UISearchResultsUpdating

我在 viewDidLoad 中有以下代码，它可以运行并添加一个搜索栏：

And I have the following code in viewDidLoad, which works and adds a search bar:

// Search controller
searchController = [[UISearchController alloc] initWithSearchResultsController:nil];
searchController.searchResultsUpdater = self;
searchController.dimsBackgroundDuringPresentation = NO;
searchController.searchBar.delegate = self;

// Add the search bar
self.tableView.tableHeaderView = searchController.searchBar;
self.definesPresentationContext = YES;
[searchController.searchBar sizeToFit];

这就是我所拥有的！

我将非常感谢有关如何在现有的objective-c app tableview中实现新的UISearchController的任何指针，示例代码或教程。

I would appreciate any pointers, example code or tutorials on how to implement the new UISearchController in an existing objective-c app tableview.

推荐答案

按照上述步骤进行初始化。

Initialise Following things as per steps mentioned.

1） 中的协议声明< UISearchBarDelegate， .h接口类中的UISearchControllerDelegate，UISearchResultsUpdating>

2）声明以下属性

//Fetch result controller 
@property (nonatomic, strong) UISearchController *searchController;

//for the results to be shown with two table delegates
@property (nonatomic, strong) CLCustomerResultrowsItemsCellController *searchResultsController;

//this custom controller is only suppose to have number of rows and cell for row function of table datasource

3）状态恢复

 @property BOOL searchControllerWasActive;
 @property BOOL searchControllerSearchFieldWasFirstResponder;

4）在ViewDidload的此步骤中初始化代码

_searchResultsController = [[CLChatContactsSearchResultController alloc] init];
_searchController = [[UISearchController alloc] initWithSearchResultsController:_searchResultsController];

self.searchController.searchResultsUpdater = self;
self.searchController.searchBar.placeholder = nil; 
[self.searchController.searchBar sizeToFit];
self.contactsTableView.tableHeaderView = self.searchController.searchBar;


// we want to be the delegate for our filtered table so didSelectRowAtIndexPath is called for both tables
self.searchResultsController.tableView.delegate = self;
self.searchController.delegate = self;
self.searchController.dimsBackgroundDuringPresentation = YES; // 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

5）使用Button甚至启动控制器和过去这些功能以供将来使用，如果有任何看到评论

#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
}

6）在搜索文本时，您会收到此回调

#pragma mark - UISearchResultsUpdating

- (void)updateSearchResultsForSearchController:(UISearchController *)searchController {

    // update the filtered array based on the search text
    NSString *searchText = searchController.searchBar.text;

    id <NSFetchedResultsSectionInfo> sectionInfo = [_fetchedResultsController.sections objectAtIndex:0];

    if (searchText == nil) {

        // If empty the search results are the same as the original data
        self.searchResults = [sectionInfo.objects mutableCopy];

    } else {

        NSMutableArray *searchResults = [[NSMutableArray alloc] init];

        NSArray *allObjects = sectionInfo.objects;

        for (PhoneNumber *phoneMO in allObjects) {

            if ([phoneMO.number containsString:searchText] || [[phoneMO.closrr_id filteredId] containsString:searchText] || [[phoneMO.contact.fullname lowercaseString] containsString:[searchText lowercaseString]]) {
                [searchResults addObject:phoneMO];
            }
        }

        self.searchResults = searchResults;

    }

    // hand over the filtered results to our search results table
    CLCustomerResultrowsItemsCellController *tableController = (CLCustomerResultrowsItemsCellController *)self.searchController.searchResultsController;
    tableController.filteredContacts = self.searchResults;
    [tableController.tableView reloadData];
}

7）您必须在Custom类中声明filteredContacts属性这将填充搜索的项目。

8）多数民众赞成在选择行比较表视图，如果它是主控制器或自定义控制器类表视图并对所选项目执行操作。

希望这有用。

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