dequeueReusableCellWithIdentifier返回nil

Question

我正在使用Storyboard的原型UITableViewCell，并在cellForRowAtIndexPath中调用dequeueReusableCellWithIdentifier时获取nil。我已经三次检查原型tableviewcell的Xcode标识符是＆＃34; PersonCell＆＃34;，删除原型单元并再次添加它，注释掉UITearchDisplyDelegate和UISearchBarDelegate继承UITableViewController，仍然得到nil 。我很难过。有没有人碰到这个？

#import "PeopleGroupPickerViewController.h"
#import "DAL.h"
#import "Person.h"

@interface PeopleGroupPickerViewController ()

@end

@implementation PeopleGroupPickerViewController
{
 NSArray *people;
 NSArray *searchResults;
}

- (id)initWithStyle:(UITableViewStyle)style
{
    self = [super initWithStyle:style];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];

    // Uncomment the following line to preserve selection between presentations.
    // self.clearsSelectionOnViewWillAppear = NO;

    // Uncomment the following line to display an Edit button in the navigation bar for this view controller.
    // self.navigationItem.rightBarButtonItem = self.editButtonItem;
 people = [[DAL sharedInstance] getPeople:false];
 [self.tableView registerClass:[GenericDetailCell class] forCellReuseIdentifier:@"PersonCell"];
}

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

- (void)filterContentForSearchText:(NSString*)searchText scope:(NSString*)scope
{
 NSString *lastNameSearch = searchText.lowercaseString;
 NSString *firstNameSearch = @"";
 if ([lastNameSearch rangeOfString:@","].length > 0)
 {
  NSArray *names = [lastNameSearch componentsSeparatedByString:@","];
  //NSLog(@"names count",names.count);
  if(names.count > 1)
  {
   lastNameSearch = names[0];
   firstNameSearch = names[1];
   //NSLog(@"first %@ last %@",firstNameSearch,lastNameSearch);
  }
 }

 NSMutableString *predicateText = [[NSMutableString alloc] initWithFormat:@"(sLastName contains[c] '%@')",lastNameSearch];
 if(![firstNameSearch isEqualToString:@""])
 {
  [predicateText appendFormat:@" AND (sFirstName contains[c] '%@')",firstNameSearch];
 }
 NSPredicate *resultPredicate = [NSPredicate predicateWithFormat:predicateText.copy];
 searchResults = [people filteredArrayUsingPredicate:resultPredicate];
 NSLog(@"filterContentForSearchText, searching for %@, # results: %d",predicateText, searchResults.count);
}

-(BOOL) searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchString:(NSString *)searchString
{
 [self filterContentForSearchText:searchString scope:nil];
 return YES;
}

#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
 if(tableView == self.searchDisplayController.searchResultsTableView)
 {
  return 1;
 }
 else
 {
  return 1;
 }
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
 if(tableView == self.searchDisplayController.searchResultsTableView)
 {
  return searchResults.count;
 }
 else
 {
  return people.count;
 }
}


- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
 GenericDetailCell *cell = [tableView dequeueReusableCellWithIdentifier:@"PersonCell" forIndexPath:indexPath];

 Person_ *thisPerson;
 if(tableView == self.searchDisplayController.searchResultsTableView)
 {
  thisPerson = (Person_ *) searchResults[indexPath.row];
 }
 else
 {
  thisPerson = (Person_ *) people[indexPath.row];
 }
 Person_ *thisSpouse = [[DAL sharedInstance] getSpouse:thisPerson People:people];

 cell.fieldName.text = thisPerson.sName;
 cell.fieldValue.text = thisSpouse.sName;

 return cell;
}

Answer 1

正如Maddy在评论中所述，你应该自己创建单元格，如果它是零，或者在你的viewDidLoad中或在适当的情况下，你可以调用其中一种方法让tableview为你创建单元格< / p>

<强>目标c

[self.tableView registerClass:<#(__unsafe_unretained Class)#> forCellReuseIdentifier:<#(NSString *)#>]
[self.tableView registerNib:<#(UINib *)#> forCellReuseIdentifier:<#(NSString *)#>]

<强>夫特

tableView.register(MyTableViewCell.self, forCellReuseIdentifier: "CellID1")
tableView.register(UINib(nibName: "yourNibName", bundle: nil), forCellReuseIdentifier: "CellID2")

Answer 2

在设置＆＃34;恢复ID＆＃34;之后我遇到了这个问题。在身份检查员。设置reuseIdentifier的正确位置是＆＃34;标识符＆＃34;在“属性”检查器中找到的字段。

Answer 3

添加@Fonix答案

确保Inherit Module From Target已启用

Answer 4

如果容纳单元格的CABasicAnimation并没有同时将viewcontroller分配为tableview的委托和数据源，则会发生这种情况。