ios - 去 Segue 还是去 didSelectRowAtIndexPath？

Question

下面是我当前正在运行的代码。我有一个带有导航 Controller 和 TableView Controller 以及 View Controller 的 Storyboard设置。我正在尝试将我为表设置的 NSDictionary 中的名称传递给详细 View Controller 。我应该使用 prepareforsegue 还是 didselectrowatindexpath 以及如何从字典中获取名称以传递它？

#import "FMInboxViewController.h"
#import "FMDetailViewController.h"

@interface FMInboxViewController ()

@end

@implementation FMInboxViewController

@synthesize keyArray;
@synthesize tableArray;
@synthesize tblDictionary;
@synthesize filteredArray;

- (void)viewDidLoad
{
    [super viewDidLoad];

    NSMutableArray *ary=[[NSMutableArray alloc]init];
    [ary addObject:@"Adam"];
    [ary addObject:@"Fred"];
    [ary addObject:@"Angel"];
    // ... many similar entries
    [ary addObject:@"James"];
    [ary addObject:@"Mukthesh"];

    self.tblDictionary =[self fillingDictionary:ary];
}

TableView 数据源

#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    // Return the number of sections.
    return [keyArray count];
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    // Return the number of rows in the section.
    NSArray *ary = [self.tblDictionary valueForKey:[keyArray objectAtIndex:section]];
    return [ary count];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];

    NSString *key = [keyArray objectAtIndex:[indexPath section]];
    NSArray *array = (NSArray *)[self.tblDictionary valueForKey:key];
    NSString *cellTitle = [array objectAtIndex:[indexPath row]];
    cell.textLabel.text = cellTitle;

    // Configure the cell...

    return cell;
}

-(NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section {
    NSString *title = [keyArray objectAtIndex:section];
    return title;
}

//-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
//    NSString *key = [keyArray objectAtIndex:[indexPath section]];
//    NSArray *array = (NSArray *)[self.tblDictionary valueForKey:key];
//    self.selectedName = [array objectAtIndex:indexPath.row];
//    NSLog(@"Selected Name in Did select: %@", self.selectedName);
//    
//    [self performSegueWithIdentifier:@"showDetail" sender:self];
//}

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    if ([segue.identifier isEqualToString:@"showDetail"]) {
        NSIndexPath *section = [self.tableView indexPathForSelectedRow];
        NSString *key = [keyArray objectAtIndex:section];
        NSArray *array = (NSArray *)[self.tblDictionary valueForKey:key];
        NSString *cellTitle = [array objectAtIndex:[indexPath row]];
        NSLog(@"Selected Name in Did select: %@", self.selectedName);
    }
}

辅助方法

#pragma mark - Helper Methods

- (NSMutableDictionary *)fillingDictionary:(NSMutableArray *)sentArray {
    keyArray = [[NSMutableArray alloc] init];
    [keyArray removeAllObjects];
    NSMutableDictionary *dic = [[NSMutableDictionary alloc] init];
    [sentArray sortUsingSelector:@selector(compare:)];
    for ( NSString *str in sentArray) {
        NSString *charVal = [str substringToIndex:1];
        NSString *charStr = [NSString stringWithString:charVal];
        NSLog(@" charStr = %@", charStr);
        if (![keyArray containsObject:charStr]) {
            NSMutableArray *charArray = [[NSMutableArray alloc] init];
            [charArray addObject:str];
            [keyArray addObject:charStr];
            [dic setValue:charArray forKey:charStr];
        }
        else {
            NSMutableArray *prevArray = (NSMutableArray *)[dic valueForKey:charStr];
            [prevArray addObject:str];
            [dic setValue:prevArray forKeyPath:charStr];
        }
    }

    return dic;
}


@end

好的，我把那个部分改成了这样

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    NSString *key = [keyArray objectAtIndex:[indexPath section]];
    NSArray *array = (NSArray *)[self.tblDictionary valueForKey:key];
    self.selectedName = [array objectAtIndex:indexPath.row];
    NSLog(@"Selected Name in Did select: %@", self.selectedName);
}

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    FMDetailViewController *dvc = (FMDetailViewController *)segue.destinationViewController;
    dvc.name = self.selectedName;
}

但是现在，当我选择行时，名称不会在第一次按下时显示在详细信息 Controller 中。如果你返回并选择另一个名字，你按下的名字就会显示在 View Controller 中。关于为什么会出现这种情况有什么建议吗？

Answer 1

你需要同时使用两者，在 didSelectRowAtIndexPath 中你应该调用 [self performSegueWithIdentifier:@"identifier"sender:self];

在同一个 View Controller 中，您应该使用 prepareForSegue 方法从 segue 中获取 destinationViewController，然后在该 View Controller 上设置您希望设置的任何属性.

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    self.someProperty = [self.someArray objectAtIndex:indexPath.row];
    [self performSegueWithIdentifier:@"segueID" sender:self];
}

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    UIViewController *vcToPushTo = segue.destinationViewController;
    vcToPushTo.propertyToSet = self.someProperty;
}