Ios 如何使用核心数据实现表节

我正在iOS应用程序中使用核心数据。我有一个tableview来显示来自一个名为persons的实体的数据。实体人员有几个属性，其中一个属性是“日期”。我想在表视图中创建5个永久部分（0.今天，1.明天，2.本周，3.本月，4.即将到来），然后我想根据日期在每个部分上显示数据。 我一直在搜索这个问题，但没有找到可以应用于我的应用程序的问题。 我恳请你告诉我正确的处理方法

这是我目前的代码：

#import "PersonsTVC.h"
#import "Person.h"

@implementation PersonsTVC
@synthesize fetchedResultsController = __fetchedResultsController;
@synthesize managedObjectContext = __managedObjectContext;
@synthesize selectedPerson;
@synthesize searchResults,titulosseccion;

- (void)setupFetchedResultsController
{
    // 1 - Decide what Entity you want
    NSString *entityName = @"Person"; // Put your entity name here
    NSLog(@"Setting up a Fetched Results Controller for the Entity named %@", entityName);

    // 2 - Request that Entity
    NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:entityName];

    // 3 - Filter it if you want
    //request.predicate = [NSPredicate predicateWithFormat:@"Person.name = Blah"];

    // 4 - Sort it if you want
    request.sortDescriptors = [NSArray arrayWithObject:[NSSortDescriptor sortDescriptorWithKey:@"firstname"
                                                                                     ascending:YES
                                                                                      selector:@selector(localizedCaseInsensitiveCompare:)]];
    // 5 - Fetch it
    self.fetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:request
                                                                        managedObjectContext:self.managedObjectContext
                                                                          sectionNameKeyPath:nil
                                                                                   cacheName:nil];
    [self performFetch];
}



- (void) viewDidLoad
{



    self.searchResults = [NSMutableArray arrayWithCapacity:[[self.fetchedResultsController fetchedObjects] count]];
    [self.tableView reloadData];
}





-(void) viewDidUnload{
    self.searchResults = nil;
}



- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    [self setupFetchedResultsController];
}

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
    return [[self.fetchedResultsController sections] count];


}


- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{

    // Perform segue to detail when a SEARCH table cell is touched
    if(tableView == self.searchDisplayController.searchResultsTableView)
    {
        [self performSegueWithIdentifier:@"Person Detail Segue" sender:tableView];
    }

}



- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Persons Cell";

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
    }

    // Configure the cell...
    // Configure the cell...
    Person  *person = nil;

    if (tableView == self.searchDisplayController.searchResultsTableView)
    {
        NSLog(@"Configuring cell to show search results");
        person = [self.searchResults objectAtIndex:indexPath.row];
    }
    else
    {
        NSLog(@"Configuring cell to show normal data");
        person = [self.fetchedResultsController objectAtIndexPath:indexPath];
    }








    NSString *fullname = [NSString stringWithFormat:@"%@ %@", person.firstname, person.surname];
    cell.textLabel.text = person.firstname;
    if ([person.inRole.color isEqual :@"Yellow"])
    {
        cell.imageView.image = [UIImage imageNamed:@"Yellow"];
    }
    if ([person.inRole.color isEqual :@"Black"])
    {
        cell.imageView.image = [UIImage imageNamed:@"Black"];
    }
    if ([person.inRole.color isEqual :@"Grey"])
    {
        cell.imageView.image = [UIImage imageNamed:@"Grey"];
    }
    if ([person.inRole.color isEqual :@"Red"])
    {
        cell.imageView.image = [UIImage imageNamed:@"Red"];
    }
    if ([person.inRole.color isEqual :@"Blue"])
    {
        cell.imageView.image = [UIImage imageNamed:@"Blue"];
    }
    if ([person.inRole.color isEqual :@"Dark Green"])
    {
        cell.imageView.image = [UIImage imageNamed:@"DarkGreen"];
    }
    if ([person.inRole.color isEqual :@"Light Green"])
    {
        cell.imageView.image = [UIImage imageNamed:@"LightGreen"];
    }
    if ([person.inRole.color isEqual :@"Light Blue"])
    {
        cell.imageView.image = [UIImage imageNamed:@"LightBlue"];
    }
    if ([person.inRole.color isEqual :@"Brown"])
    {
        cell.imageView.image = [UIImage imageNamed:@"Brown"];
    }
    if ([person.inRole.color isEqual :@"Dark Orange"])
    {
        cell.imageView.image = [UIImage imageNamed:@"DarkOrange"];



    }

    NSDate *fechasinformat = person.date;
    NSString *fecha0 = [NSString stringWithFormat:@"%@", fechasinformat];


   cell.detailTextLabel.text = fecha0;



    return cell;
}


- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    if (tableView == self.searchDisplayController.searchResultsTableView)
    {
        return [self.searchResults count];
    }
    else
    {
        return [[[self.fetchedResultsController sections] objectAtIndex:section] numberOfObjects];
    }
}


- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {

    if (editingStyle == UITableViewCellEditingStyleDelete) {

        [self.tableView beginUpdates]; // Avoid  NSInternalInconsistencyException

        // Delete the person object that was swiped
        Person *personToDelete = [self.fetchedResultsController objectAtIndexPath:indexPath];
        NSLog(@"Deleting (%@)", personToDelete.firstname);
        [self.managedObjectContext deleteObject:personToDelete];
        [self.managedObjectContext save:nil];

        // Delete the (now empty) row on the table
        [self.tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
        [self performFetch];

        [self.tableView endUpdates];
    }
}

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if ([segue.identifier isEqualToString:@"Add Person Segue"])
    {
        NSLog(@"Setting PersonsTVC as a delegate of PersonDetailTVC");
        PersonDetailTVC *personDetailTVC = segue.destinationViewController;
        personDetailTVC.delegate = self;

        NSLog(@"Creating a new person and passing it to PersonDetailTVC");
        Person *newPerson = [NSEntityDescription insertNewObjectForEntityForName:@"Person"
                                                          inManagedObjectContext:self.managedObjectContext];

        personDetailTVC.person = newPerson;
    }
    else if ([segue.identifier isEqualToString:@"Person Detail Segue"])
    {
        NSLog(@"Setting PersonsTVC as a delegate of PersonDetailTVC");
        PersonDetailTVC *personDetailTVC = segue.destinationViewController;
        personDetailTVC.delegate = self;

        // Store selected Person in selectedPerson property
        if(sender == self.searchDisplayController.searchResultsTableView)
        {
            NSIndexPath *indexPath = [self.searchDisplayController.searchResultsTableView indexPathForSelectedRow];
            self.selectedPerson = [self.searchResults objectAtIndex:[indexPath row]];
        }
        else
        {
            NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];
            self.selectedPerson = [self.fetchedResultsController objectAtIndexPath:indexPath];
        }

        NSLog(@"Passing selected person (%@) to PersonDetailTVC",    self.selectedPerson.firstname);
        personDetailTVC.person = self.selectedPerson;
    }
    else
    {
        NSLog(@"Unidentified Segue Attempted!");
    }
}

- (void)theSaveButtonOnThePersonDetailTVCWasTapped:(PersonDetailTVC *)controller
{
    // do something here like refreshing the table or whatever

    // close the delegated view
    [controller.navigationController popViewControllerAnimated:YES];    
}

#pragma mark -
#pragma mark Content Filtering

-(void)filterContentForSearchText:(NSString*)searchText scope:(NSString*)scope {
    self.searchResults = [[self.fetchedResultsController fetchedObjects] filteredArrayUsingPredicate:[NSPredicate predicateWithBlock:^BOOL(id evaluatedObject, NSDictionary *bindings) {
        Person* person = evaluatedObject;
        NSString* firstName = person.firstname;

        //searchText having length < 3 should not be considered
        if (!!searchText && [searchText length] < 3) {
            return YES;
        }

        if ([scope isEqualToString:@"All"] || [firstName isEqualToString:scope])  {
            return ([firstName rangeOfString:searchText].location != NSNotFound);
        }
        return NO; //if nothing matches
    }]];
}

#pragma mark -
#pragma mark UISearchDisplayController Delegate Methods

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

- (BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchScope:(NSInteger)searchOption
{
    [self filterContentForSearchText:[self.searchDisplayController.searchBar text] scope:@"All"];
    return YES;
}



@end

#导入“PersonsTVC.h”
#输入“Person.h”
@执行人员
@综合fetchedResultsController=\uu fetchedResultsController；
@综合managedObjectContext=u managedObjectContext；
@综合选人；
@综合搜索结果，Tituloseccion；
-（无效）setupFetchedResultsController
{
//1-决定您想要的实体
NSString*entityName=@“Person”//请在此处输入您的实体名称
NSLog（@“为名为%@的实体设置获取结果控制器”，entityName）；
//2-请求该实体
NSFetchRequest*request=[NSFetchRequest fetchRequestWithEntityName:entityName]；
//3-如果需要，可以对其进行过滤
//request.predicate=[NSPredicate predicateWithFormat:@“Person.name=Blah”]；
//4-如果需要，请进行排序
request.sortDescriptors=[NSArray arrayWithObject:[NSSortDescriptor SortDescriptor WithKey:@“firstname”
上升：是的
选择器：@selector（localizedCaseInsensitiveCompare:）]；
//5-拿过来
self.fetchedResultsController=[[NSFetchedResultsController alloc]initWithFetchRequest:request
managedObjectContext:self.managedObjectContext
sectionNameKeyPath:无
cacheName:nil]；
[自执行蚀刻]；
}
-（无效）viewDidLoad
{
self.searchResults=[NSMutableArray阵列容量：[[self.fetchedResultsController fetchedObjects]计数]]；
[self.tableView重载数据]；
}
-（无效）视图卸载{
self.searchResults=nil；
}
-（无效）视图将显示：（BOOL）动画
{
[超级视图将显示：动画]；
[自设置FetchedResultsController]；
}
-（NSInteger）表格视图中的节数：（UITableView*）表格视图{
返回[[self.fetchedResultsController节]计数]；
}
-（void）tableView:（UITableView*）tableView未选择RowatineXpath:（NSIndexPath*）indexPath
{
//触摸搜索表单元格时，执行segue to detail
if（tableView==self.searchDisplayController.searchResultsTableView）
{
[self-PerformsgueWithIdentifier:@“个人详细信息序列”发件人：tableView]；
}
}
-（UITableViewCell*）tableView:（UITableView*）tableView cellForRowAtIndexPath:（NSIndexPath*）indexPath
{
静态NSString*CellIdentifier=@“个人单元格”；
UITableViewCell*单元格=[tableView dequeueReusableCellWithIdentifier:CellIdentifier]；
如果（单元格==nil）{
cell=[[UITableViewCell alloc]initWithStyle:UITableViewCellStyleDefault重用标识符：CellIdentifier]；
}
//配置单元格。。。
//配置单元格。。。
人*人=零；
if（tableView==self.searchDisplayController.searchResultsTableView）
{
NSLog（@“配置单元格以显示搜索结果”）；
person=[self.searchResults objectAtIndex:indexPath.row]；
}
其他的
{
NSLog（@“配置单元格以显示正常数据”）；
person=[self.fetchedResultsController对象索引路径：indexPath]；
}
NSString*fullname=[NSString stringWithFormat:@“%@%@”，person.firstname，person.姓氏]；
cell.textlab.text=person.firstname；
如果（[person.inRole.color isEqual:@“Yellow”]）
{
cell.imageView.image=[UIImage ImageName:@“黄色”]；
}
如果（[person.inRole.color isEqual:@“Black”]）
{
cell.imageView.image=[UIImage ImageName:@“黑色”]；
}
如果（[person.inRole.color isEqual:@“Grey”]）
{
cell.imageView.image=[UIImage ImageName:@“灰色”]；
}
如果（[person.inRole.color isEqual:@“Red”]）
{
cell.imageView.image=[UIImage ImageName:@“红色”]；
}
如果（[person.inRole.color isEqual:@“Blue”]）
{
cell.imageView.image=[UIImage ImageName:@“蓝色”]；
}
如果（[person.inRole.color isEqual:@“深绿色”]）
{
cell.imageView.image=[UIImage ImageName:@“暗绿色”]；
}
如果（[person.inRole.color isEqual:@“浅绿色”]）
{
cell.imageView.image=[UIImage ImageName:@“浅绿色”]；
}
如果（[person.inRole.color isEqual:@“浅蓝色”]）
{
cell.imageView.image=[UIImage ImageName:@“LightBlue”]；
}
如果（[person.inRole.color isEqual:@“Brown”]）
{
cell.imageView.image=[UIImage ImageName:@“Brown”]；
}
如果（[person.inRole.color isEqual:@“深橙色”]）
{
cell.imageView.image=[UIImage ImageName:@“DarkOrange”]；
}
NSDate*fechasformat=person.date；
NSString*fecha0=[NSString stringWithFormat:@“%@”，fechasinformat]；
cell.detailTextLabel.text=fecha0；
返回单元；
}
-（NSInteger）表视图：（UITableView*）表视图行数节：（NSInteger）节
{
if（tableView==self.searchDisplayController.searchResultsTableView）
{
返回[self.searchResults计数]；
}
其他的
{
返回[[[self.fetchedResultsController节]对象索引：节]numberOfObjects]；
}
}
-（void）tableView:（UITableView*）tableView提交的编辑样式：（UITableViewCellEditingStyle）行的编辑样式索引路径：（NSIndexPath*）索引路径{
如果（editingStyle==UITableViewCellEditingStyleDelete）{
[self.tableView-be
// First sort descriptor (required for grouping into sections):
NSSortDescriptor *sortByDate = [[NSSortDescriptor alloc] initWithKey:@"date" ascending:YES];
// Second sort descriptor (for the items within each section):
NSSortDescriptor *sortByName = [[NSSortDescriptor alloc] initWithKey:@"firstname" ascending:YES];
[request setSortDescriptors:@[sortByDate, sortByName]];

- (NSString *)sectionIdentifier
{
    [self willAccessValueForKey:@"sectionIdentifier"];
    NSString *tmp = [self primitiveValueForKey:@"sectionIdentifier"];
    [self didAccessValueForKey:@"sectionIdentifier"];

    if (!tmp)
    {
        NSDate *date = self.date;
        // Using pseudo-code here:
        if ("date is from today") {
            tmp = @"0";
        } else if ("date is from tomorrow") {
            tmp = @"1";
        } else ... // and so on ...

        [self setPrimitiveValue:tmp forKey:@"sectionIdentifier"];
    }
    return tmp;
}

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section
{
    id <NSFetchedResultsSectionInfo> theSection = [[self.fetchedResultsController sections] objectAtIndex:section];

    NSString *sectionName = [theSection name];
    if ([sectionName isEqualToString:@"0"]) {
        return @"Today";
    } else if ([sectionName isEqualToString:@"1"]) {
        return @"Tomorrow";
    } ... // and so on ...
    } else {
        return @"Other";
    }
}