如何将节与其UITableView中的headerLabel关联

Question

Every section in my UITableView has a headerLabel.text value, and what I want is for it to use this value as a parameter in the deleteFromMatchCenter function thats run inside of the deleteButtonPressed IBAction.

I've attempted to do that as you can see in my code, but as expected, the app won't compile because headerLabel.text isn't a public property. How can I make it so that the delete button on a section uses its specific headerLabel as the parameter?

MatchCenterViewController.h:

#import <UIKit/UIKit.h>
#import <Parse/Parse.h>
#import "AsyncImageView.h"
#import "SearchViewController.h"

@interface MatchCenterViewController : UIViewController <UITableViewDataSource>

@property (nonatomic) IBOutlet NSString *itemSearch;

@property (nonatomic, strong) NSArray *imageURLs;
@property (strong, nonatomic) NSString *matchingCategoryCondition;
@property (strong, nonatomic) NSString *matchingCategoryLocation;
@property (strong, nonatomic) NSNumber *matchingCategoryMaxPrice;
@property (strong, nonatomic) NSNumber *matchingCategoryMinPrice;

@property (strong, nonatomic) NSArray *matchCenterArray;
@property (strong, nonatomic) NSString *searchTerm;

@end  

MatchCenterViewController.m:

#import "MatchCenterViewController.h"
#import <UIKit/UIKit.h>

@interface MatchCenterViewController () <UITableViewDataSource, UITableViewDelegate>
@property (nonatomic, strong) UITableView *matchCenter;
@end

@implementation MatchCenterViewController


- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
    }
    return self;
}


- (void)viewDidLoad
{
    [super viewDidLoad];

    self.matchCenter = [[UITableView alloc] initWithFrame:self.view.bounds style:UITableViewCellStyleSubtitle];
    self.matchCenter.frame = CGRectMake(0,50,320,self.view.frame.size.height-100);
    _matchCenter.dataSource = self;
    _matchCenter.delegate = self;
    [self.view addSubview:self.matchCenter];

    _matchCenterArray = [[NSArray alloc] init];
}

- (void)viewDidAppear:(BOOL)animated
{
    self.matchCenterArray = [[NSArray alloc] init];

    [PFCloud callFunctionInBackground:@"MatchCenter"
                       withParameters:@{
                                        @"test": @"Hi",
                                        }
                                block:^(NSArray *result, NSError *error) {

                                    if (!error) {
                                        _matchCenterArray = result;
                                        [_matchCenter reloadData];

                                        NSLog(@"Result: '%@'", result);
                                    }
                                }];
}


- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return _matchCenterArray.count;
}

//the part where i setup sections and the deleting of said sections

- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section {
    return 21.0f;
}


- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section {
    UIView *headerView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 21)];
    headerView.backgroundColor = [UIColor lightGrayColor];

    _searchTerm = [[[[_matchCenterArray  objectAtIndex:section] objectForKey:@"Top 3"] objectAtIndex:3]objectForKey:@"Search Term"];

    UILabel *headerLabel = [[UILabel alloc] initWithFrame:CGRectMake(8, 0, 250, 21)];
    headerLabel.text = [NSString stringWithFormat:@"%@", _searchTerm];
    headerLabel.font = [UIFont boldSystemFontOfSize:[UIFont systemFontSize]];
    headerLabel.textColor = [UIColor whiteColor];
    headerLabel.backgroundColor = [UIColor lightGrayColor];
    [headerView addSubview:headerLabel];

    UIButton *deleteButton = [UIButton buttonWithType:UIButtonTypeCustom];
    deleteButton.tag = section + 1000;
    deleteButton.frame = CGRectMake(300, 2, 17, 17);
    [deleteButton setImage:[UIImage imageNamed:@"xbutton.png"] forState:UIControlStateNormal];
    [deleteButton addTarget:self action:@selector(deleteButtonPressed:) forControlEvents:UIControlEventTouchUpInside];
    [headerView addSubview:deleteButton];
    return headerView;
}



- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
     return 3;
}


- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Initialize cell
    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (!cell) {
        // if no cell could be dequeued create a new one
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier];
    }

    // No cell seperators = clean design
    tableView.separatorColor = [UIColor clearColor];

    // title of the item
    cell.textLabel.text = _matchCenterArray[indexPath.section][@"Top 3"][indexPath.row][@"Title"];
    cell.textLabel.font = [UIFont boldSystemFontOfSize:14];

    // price of the item
    cell.detailTextLabel.text = [NSString stringWithFormat:@"$%@", _matchCenterArray[indexPath.section][@"Top 3"][indexPath.row][@"Price"]];
    cell.detailTextLabel.textColor = [UIColor colorWithRed:0/255.0f green:127/255.0f blue:31/255.0f alpha:1.0f];

    // image of the item
    NSData *imageData = [NSData dataWithContentsOfURL:[NSURL URLWithString:_matchCenterArray[indexPath.section][@"Top 3"][indexPath.row][@"Image URL"]]];
    [[cell imageView] setImage:[UIImage imageWithData:imageData]];
    //[cell imageView].frame = CGRectMake(45.0,10.0,10,10);

    return cell;

}


- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return 65;
}


- (IBAction)deleteButtonPressed:(UIButton *)sender {

    [PFCloud callFunctionInBackground:@"deleteFromMatchCenter"
                       withParameters:@{
                                        @"searchTerm": headerLabel.text,
                                        }
                                block:^(NSDictionary *result, NSError *error) {

                                    if (!error) {
                                        NSLog(@"Result: '%@'", result);
                                        [_matchCenter reloadData];
                                    }
                                }];
}



- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}


/*
#pragma mark - Navigation

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    // Get the new view controller using [segue destinationViewController].
    // Pass the selected object to the new view controller.
}
*/

@end

Answer 1

You're using the tag property of the button to store the section it belongs to. So messy.

- (NSString *)textForSection:(NSInteger)section {
    [[[[_matchCenterArray  objectAtIndex:section] objectForKey:@"Top 3"] objectAtIndex:section] objectForKey:@"Search Term"];
}

- (IBAction)deleteButtonPressed:(UIButton *)sender {
    NSString *sectionText = [self textForSection:(sender.tag - 1000)];
    [PFCloud callFunctionInBackground:@"deleteFromMatchCenter"
                       withParameters:@{
                                        @"searchTerm": sectionText,
                                        }
                                block:^(NSDictionary *result, NSError *error) {

                                    if (!error) {
                                        NSLog(@"Result: '%@'", result);
                                        [_matchCenter reloadData];
                                    }
                                }];
}

I think you should change your deleteButtonPressed method to take a section.

viewForHeaderInSection

UIButton *deleteButton = [UIButton buttonWithAction:^{
    [self deleteButtonPressedForSection:section];
}];

Delete Method

- (void)deleteButtonPressedForSection:(NSInteger)section {
    NSString *sectionText = [self textForSection:section];
}

UIButton Category

+ (instancetype)buttonWithAction:(CompletionBlock)action {
    UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
    [button addTarget:action action:@selector(invoke) forControlEvents:UIControlEventTouchUpInside];
    [button setAssociatedObject:action forSelector:_cmd]; //you're going to have to write this method yourself
    return button;
}