didSelectRowAtIndexPath Segue 返回垃圾

Posted 2023-02-27

【中文标题】didSelectRowAtIndexPath Segue 返回垃圾

【英文标题】：didSelectRowAtIndexPath Segue returning junk

【发布时间】：2014-11-11 04:18:15

【问题描述】：

所以，我试图将我选择的单元格传递给以前的 VC，每次单击任何行时，它总是只发送字符串“Apples”。我不确定为什么。有任何想法吗？ 注意：mySelectedCell 是在 ChoicesTableViewController 的 .h 文件中初始化的 NSString 我试图从

传递数据的 .m 文件

@interface ChoicesTableViewController () <UITableViewDelegate, UITableViewDataSource>
@property (weak, nonatomic) IBOutlet UITableView *myTableView;
@property (strong, nonatomic) NSMutableArray *items;
@property (strong, nonatomic) NSMutableDictionary *alphabetizedItems;

@property (strong, nonatomic) NSArray *unsortedKeys;
@property (strong, nonatomic) NSArray *sortedKeys;

@end

@implementation ChoicesTableViewController
- (id)initWithStyle:(UITableViewStyle)style

    self = [super initWithStyle:style];
    if (self) 
        // Custom initialization
    
    return self;


- (void)viewDidLoad

    [super viewDidLoad];
    self.myTableView.delegate = self;
    self.myTableView.dataSource = self;

    self.items = [[NSMutableArray alloc] init];
    [self.items addObject:@"Apples"];
    [self.items addObject:@"Bread"];
    [self.items addObject:@"Butter"];
    [self.items addObject:@"Cheese"];
    [self.items addObject:@"Eggs"];
    [self.items addObject:@"Grapes"];
    [self.items addObject:@"Ice Cream"];
    [self.items addObject:@"Milk"];
    [self.items addObject:@"Oranges"];
    [self.items addObject:@"Oreos"];
    self.alphabetizedItems = [self alphabetizeItems:self.items];



//Segue if the item is tapped
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath


    self.mySelectedCell = [self.items objectAtIndex:indexPath.row];

    [self performSegueWithIdentifier:@"unwindSegueAction" sender:self];


//unwind segue from add choice

- (IBAction)unwindSegueToChoices:(UIStoryboardSegue *)segue


    AddChoiceViewController *sourceVC = segue.sourceViewController;
    NSString *myNewItem = sourceVC.myTextField.text;
    //NSString *myFinalString = [[myNewItem substringToIndex:1] capitalizedString];
    NSString *stringCapitalized = [myNewItem capitalizedString];
    [self.items addObject:stringCapitalized];
    self.alphabetizedItems = [self alphabetizeItems:self.items];
    //[self.arrayNames addObjectsFromArray:@[[MyDataChoices itemWithNewName:stringCapitalized]]];
    [self.tableView reloadData];


//titles for talble view
#pragma mark Helper Methods
- (NSMutableDictionary *)alphabetizeItems:(NSArray *)items 
    NSMutableDictionary *buffer = [[NSMutableDictionary alloc] init];

    for (int i = 0; i < [items count]; i++) 
        NSString *item = [items objectAtIndex:i];
        NSString *firstLetter = [[item substringToIndex:1] uppercaseString];

        if ([buffer objectForKey:firstLetter]) 
            [(NSMutableArray *)[buffer objectForKey:firstLetter] addObject:item];

         else 
            NSMutableArray *mutableArray = [[NSMutableArray alloc] initWithObjects:item, nil];
            [buffer setObject:mutableArray forKey:firstLetter];
        
    

    NSArray *keys = [buffer allKeys];
    for (int j = 0; j < [keys count]; j++) 
        NSString *key = [keys objectAtIndex:j];
        [(NSMutableArray *)[buffer objectForKey:key] sortUsingSelector:@selector(localizedCaseInsensitiveCompare:)];
    

    NSMutableDictionary *result = [NSMutableDictionary dictionaryWithDictionary:buffer];
    return result;

#pragma mark title indexing

-(NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section

    NSArray *keys = [[self.alphabetizedItems allKeys] sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)];
    NSString *key = [keys objectAtIndex:section];
    return key;




# pragma mark main table view
-(NSInteger) numberOfSectionsInTableView:(UITableView *) tableView

    NSArray *keys = [self.alphabetizedItems allKeys];
    return [keys count];



-(NSInteger) tableView:(UITableView *) tableView numberOfRowsInSection:(NSInteger)section

    //return self.arrayNames.count;
    self.unsortedKeys = [self.alphabetizedItems allKeys];
    self.sortedKeys = [self.unsortedKeys sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)];
    NSString *key = [self.sortedKeys objectAtIndex:section];
    NSArray *itemsForSection = [self.alphabetizedItems objectForKey:key];
    return [itemsForSection count];


-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath

    //MyDataChoices *currentRow = self.arrayNames[indexPath.row];
    UITableViewCell * cell = [tableView dequeueReusableCellWithIdentifier:@"mainCell2" forIndexPath:indexPath];

    //cell.textLabel.text = currentRow.myNameChoices;
    NSString *key = [self.sortedKeys objectAtIndex:[indexPath section]];
    NSArray *itemsForSection = [self.alphabetizedItems objectForKey:key];
    NSString *item = [itemsForSection objectAtIndex:[indexPath row]];

    [cell.textLabel setText:item];

    return cell;



# pragma Mark delete slide button

//Delete Swipe Button
// Override to support conditional editing of the table view.
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath

    // Return NO if you do not want the specified item to be editable.
    return YES;




// Override to support editing the table view.
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath

    if (editingStyle == UITableViewCellEditingStyleDelete) 
        NSArray *unsortedKeys = [self.alphabetizedItems allKeys];
        NSArray *sortedKeys = [unsortedKeys sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)];
        NSString *key = [sortedKeys objectAtIndex:[indexPath section]];
        NSArray *itemsForSection = [self.alphabetizedItems objectForKey:key];
        if (itemsForSection.count == 1) 
            // Delete the whole section
            [self.alphabetizedItems removeObjectForKey:key];
            [tableView deleteSections:[NSIndexSet indexSetWithIndex:indexPath.section] withRowAnimation:UITableViewRowAnimationFade];
         else 
            // Delete the row from the data source
            //int index = indexPath.row;
            [self.alphabetizedItems removeObjectForKey:indexPath];

            [tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade];
        
     else if (editingStyle == UITableViewCellEditingStyleInsert) 
        // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
    


- (void)didReceiveMemoryWarning

    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.



@end

我将数据传递给的 .m 文件

#import "ShoppingListTableViewTableViewController.h"
#import "myData.h"
#import "ChoicesTableViewController.h"

@interface ShoppingListTableViewTableViewController ()

@property (strong, nonatomic) NSMutableArray *itemData;

@end

@implementation ShoppingListTableViewTableViewController

- (id)initWithStyle:(UITableViewStyle)style

    self = [super initWithStyle:style];
    if (self) 
        // Custom initialization
    
    return self;


- (void)viewDidLoad

    [super viewDidLoad];

    self.itemData = [[NSMutableArray alloc] init];

    [self.itemData addObjectsFromArray:@[
                                         [myData itemWithName:@"test"]]];


- (void)didReceiveMemoryWarning

    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.


#pragma mark - Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView

    // Return the number of sections.
    return 1;


- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section

    // Return the number of rows in the section.
    return self.itemData.count;



- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath

    myData *currentRow = self.itemData[indexPath.row];
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"mainCell" forIndexPath:indexPath];
    cell.textLabel.text = currentRow.myName;
    NSString *stringCount = [NSString stringWithFormat:@"%d", currentRow.count];
    cell.detailTextLabel.text = stringCount;

    cell.imageView.image = [UIImage imageNamed:@"Box-NoCheckMark.png"];



    return cell;

//unwind segue data from choicestableviewcontroller
- (IBAction)unwindSegueAction:(UIStoryboardSegue *)segue

    ChoicesTableViewController *vcb = (ChoicesTableViewController *)segue.sourceViewController;
    BOOL isFound = false;
    for (myData *item in self.itemData)
    
        if( [item.myName isEqualToString:vcb.mySelectedCell])
        
            item.count ++;
            isFound = true;
            break;
        

    

    if(!isFound)
    
        [self.itemData addObjectsFromArray:@[[myData itemWithName:vcb.mySelectedCell]]];

    
    [self.tableView reloadData];




//Box checked
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath

    myData *check;
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"mainCell" forIndexPath:indexPath];
    if(check.checkMark)
    
        cell.imageView.image = [UIImage imageNamed:@"Box-NoCheckMark.png"];
        check.checkMark = NO;
    
    else
    
        cell.imageView.image = [UIImage imageNamed:@"Box-CheckMark.png"];
        check.checkMark = YES;
    


//Delete Button when Swiped to the left
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath

    // Return NO if you do not want the specified item to be editable.
    return YES;




// Override to support editing the table view.
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath

    if (editingStyle == UITableViewCellEditingStyleDelete) 
        // Delete the row from the data source
        int index = indexPath.row;
        [self.itemData removeObjectAtIndex:index];

        [tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade];
     else if (editingStyle == UITableViewCellEditingStyleInsert) 
        // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
    


@end

【参考方案1】：

您需要使用与cellForRowAtIndexPath indidSelectRowAtIndexPath 相同的逻辑来获取正确的字符串；你不能只使用 [self.items objectAtIndex:indexPath.row]。

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath 
    NSString *key = [self.sortedKeys objectAtIndex:[indexPath section]];
    NSArray *itemsForSection = [self.alphabetizedItems objectForKey:key];
    self.mySelectedCell  = [itemsForSection objectAtIndex:[indexPath row]];
    [self performSegueWithIdentifier:@"unwindSegueAction" sender:self];

【讨论】：

这非常有效。我不知道我在想什么。非常感谢！