PROSAGA码农传奇-Xedge-将核心数据添加到现有的iPhone项目中

0# 筱梨 | 2019-08-31 10-32

<div class =“post-text”itemprop =“text”>
   <pre>
    <code>
      +(void) insetPlusUpdate:(NSDictionary *)dataa {

NSManagedObjectContext * context;

if (![[NSThread currentThread] isMainThread]) {

context = [[NSManagedObjectContext alloc] init];

[context setPersistentStoreCoordinator:[APP_DELEGATE persistentStoreCoordinator]];
    } else {

context = [APP_DELEGATE managedObjectContext];
    }

NSFetchRequest * request = [[NSFetchRequest alloc] init];

NSEntityDescription * entity = [NSEntityDescription entityForName:@"EntityName" inManagedObjectContext:context];

[request setEntity:entity];

NSPredicate * check = [NSPredicate predicateWithFormat:@"attribute == %@", Dict[@"key"]];

[request setPredicate:check];

NSError * error = nil;

if ([context countForFetchRequest:request error:&error] == 0) {

Entity.attribute = @"";

} else {

NSArray * array = [context executeFetchRequest:request error:&error];

EntityName * entity = [array firstObject];

Entity.attribute = @"";

}

+(NSString *)fetch:(NSString *)feed_id{

NSManagedObjectContext * context;

if(![[NSThread currentThread] isMainThread]){

context = [[NSManagedObjectContext alloc] init];

[context setPersistentStoreCoordinator:[APP_DELEGATE persistentStoreCoordinator]];

} else {

context = [APP_DELEGATE managedObjectContext];

}

NSFetchRequest * request = [[NSFetchRequest alloc] init];

NSEntityDescription * entity = [NSEntityDescription entityForName:@"ENTITYNAME" inManagedObjectContext:context];

[request setEntity:entity];

NSPredicate * check = [NSPredicate predicateWithFormat:@"attribute == %@", Dict[@"key"]];

[request setPredicate:check];

NSError * error = nil;

if ([context countForFetchRequest:request error:&error] > 0) {

NSArray * array = [context executeFetchRequest:request error:&error];

ENTITYNAME * fetchData = [array firstObject];

NSString * string = fetchData.attribte[@"key"];

return string;
    }

return nil;
}

+(BOOL)delete{

NSManagedObjectContext * context;

if (![[NSThread currentThread] isMainThread]) {

context = [[NSManagedObjectContext alloc] init];

[context setPersistentStoreCoordinator:[APP_DELEGATE persistentStoreCoordinator]];

} else {

context = [APP_DELEGATE managedObjectContext];

}

NSFetchRequest * request = [[NSFetchRequest alloc] init];

NSEntityDescription * entity = [NSEntityDescription entityForName:@"ENTITYNAME" inManagedObjectContext:context];

[request setEntity:entity];

NSError *error = nil;

NSBatchDeleteRequest *deleteRequest = [[NSBatchDeleteRequest alloc] initWithFetchRequest: request];

@try{

[context executeRequest:deleteRequest error:&error];
        if([context save:&error]){

NSLog(@"Deleted");

return [context save:&error];

}
        else{

return [context save:&error];
        }

}
    @catch(NSException *exception){

NSLog(@"failed %@",exception);
        return [context save:&error];
    }

}

</code>
  </pre>
</DIV>

1# 听风～ | 2019-08-31 10-32

<div class =“post-text”itemprop =“text”>
  <H3>
    样本编码视图1
  </H3>
   <pre>
    <code>
      #import "ViewController.h"
#import "DetailViewController.h"

@interface ViewController ()
 {
  NSInteger indexPathvalue;
 }
 @end

@implementation ViewController

- (NSManagedObjectContext *)managedObjectContext {
     NSManagedObjectContext *context = nil;
     id delegate = [[UIApplication sharedApplication] delegate];
     if ([delegate performSelector:@selector(managedObjectContext)]) {
       context = [delegate managedObjectContext];
     }
   return context;
  }

- (void)viewDidLoad {
      [super viewDidLoad];
  // Do any additional setup after loading the view, typically from a nib.
    NSLog(@"call this one2");
 }

- (void)viewDidAppear:(BOOL)animated
 {
   [super viewDidAppear:animated];
   NSManagedObjectContext *managedObjectContext = [self 
   managedObjectContext];
   NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] 
   initWithEntityName:@"Details"];
   self.dataList = [[managedObjectContext executeFetchRequest:fetchRequest   
   error:nil] mutableCopy];
   [_coreDataList reloadData];

NSLog(@"call this one");
 }
    #pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
   {
     return 1;
   }

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:
   (NSInteger)section
    {
    return self.dataList.count;
    }

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

if (cell == nil)
    {
    cell = [[UITableViewCell   
    alloc]initWithStyle:UITableViewCellStyleSubtitle 
    reuseIdentifier:CellIdentifier];
    }

NSManagedObject *user = [self.dataList objectAtIndex:indexPath.row];
   cell.textLabel.text = [user valueForKey:@"name"];
      cell.detailTextLabel.text = [user valueForKey:@"mobileNumber"];
    cell.imageView.image = [UIImage imageWithData:[user
    valueForKey:@"imageView"]]; 
    return cell;
    }

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

- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:
    (NSIndexPath *)indexPath
    {
     return YES;
     }
     - (void)tableView:(UITableView *)tableView commitEditingStyle:
      (UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:
     (NSIndexPath *)indexPath
    {
    NSManagedObjectContext *context = [self managedObjectContext];
    if (editingStyle == UITableViewCellEditingStyleDelete)
    {
    [context deleteObject:[self.dataList objectAtIndex:indexPath.row]];
    NSError *error = nil;
    if (![context save:&error]) {
        NSLog(@"Can't Delete! %@ %@", error, [error localizedDescription]);
        return;
    }
    [self.dataList removeObjectAtIndex:indexPath.row];
    [_coreDataList reloadData];

}

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

- (IBAction)addBtnClick:(id)sender {
    }

#pragma mark - Navigation

// In a storyboard-based application, you will often want to do a little      
    - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
     {
   // Get the new view controller using [segue destinationViewController].
   // Pass the selected object to the new view controller.
    if ([segue.identifier isEqualToString:@"detailView"])
   {
    NSManagedObject *obj = [self.dataList objectAtIndex:indexPathvalue];
    DetailViewController *detail = segue.destinationViewController;
    detail.userData = obj;
    }

}
   @end

</code>
  </pre>
  <H3>
    样本细节视图
  </H3>
   <pre>
    <code>
             #import "DetailViewController.h"

@interface DetailViewController ()

@end

@implementation DetailViewController

- (NSManagedObjectContext *)managedObjectContext {
     NSManagedObjectContext *context = nil;
     id delegate = [[UIApplication sharedApplication] delegate];
     if ([delegate performSelector:@selector(managedObjectContext)]) {
    context = [delegate managedObjectContext];
     }
     return context;
    }

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
     if (self.userData) {
    [self.nameTxt setText:[self.userData valueForKey:@"name"]];
    [self.mobileTxt setText:[self.userData valueForKey:@"mobileNumber"]];
    [self.emailIdTxt setText:[self.userData valueForKey:@"email"]];
    }
    }

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

- (BOOL)textFieldShouldReturn:(UITextField *)textField
   {
    [textField resignFirstResponder];
    return YES;

}
     /*

</code>
  </pre>
  <H3>
    savebutton
  </H3>
   <pre>
    <code>
          - (IBAction)saveBtnClick:(id)sender {

NSManagedObjectContext *context = [self managedObjectContext];

if (self.userData) {
    // Update existing data
    [self.userData setValue:self.nameTxt.text forKey:@"name"];
    [self.userData setValue:self.mobileTxt.text forKey:@"mobileNumber"];
    [self.userData setValue:self.emailIdTxt.text forKey:@"email"];
    UIImage *sampleimage = [UIImage imageNamed:@"icon.png"];
    NSData *dataImage = UIImageJPEGRepresentation(sampleimage, 1.0);
    [self.userData setValue:dataImage forKey:@"imageView"];

} else {
    // Create a new data
    NSManagedObject *newDevice = [NSEntityDescription   
    insertNewObjectForEntityForName:@"Details" 
    inManagedObjectContext:context];
    [newDevice setValue:self.nameTxt.text forKey:@"name"];
    [newDevice setValue:self.mobileTxt.text forKey:@"mobileNumber"];
    [newDevice setValue:self.emailIdTxt.text forKey:@"email"];
    UIImage *sampleimage = [UIImage imageNamed:@"icon.png"];
    NSData *dataImage = UIImageJPEGRepresentation(sampleimage, 1.0);
    [newDevice setValue:dataImage forKey:@"imageView"];

}

NSError *error = nil;
    // Save the object to persistent store
     if (![context save:&error]) {
    NSLog(@"Can't Save! %@ %@", error, [error localizedDescription]);
    }

[self dismissViewControllerAnimated:YES completion:nil];
    }
   @end

</code>
  </pre>
</DIV>

2# v-star*위위 | 2019-08-31 10-32

3# 敢嫁就敢娶 | 2019-08-31 10-32

4# 無口君 | 2019-08-31 10-32

<div class =“post-text”itemprop =“text”>
  <P>
    的<strong>
      对于Swift 3：包括保存和检索数据
    </强>
  </p>
  <P>
    的<strong>
      步骤1
    </强>
    ：添加框架
  </p>
  <P>
    <a href="https://i.stack.imgur.com/rue8W.png" rel="noreferrer">
      <img src =“https://i.stack.imgur.com/rue8W.png”alt =“在此处输入图片说明”/>
    </A>
  </p>
  <P>
    <a href="https://i.stack.imgur.com/2fdCT.png" rel="noreferrer">
      <img src =“https://i.stack.imgur.com/2fdCT.png”alt =“在此处输入图片说明”/>
    </A>
  </p>
  <P>
    的<strong>
      第2步：
    </强>
     添加数据模型
  </p>
  <P>
    文件＆gt;新＆gt;文件＆gt;核心数据＆gt;数据模型
  </p>
  <UL>
    <LI>
      将文件命名为
       <code>
        SampleData
      </code>
       结果文件将是
       <code>
        SampleData.xcdatamocelId
      </code>
    </LI>
  </UL>
  <P>
    的<strong>
      第3步：
    </强>
     将以下功能添加到App Delegate，并将“import CoreData”添加到顶部
  </p>
   <pre>
    <code>
      func applicationWillTerminate(_ application: UIApplication) {
    // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
    // Saves changes in the application's managed object context before the application terminates.
    self.saveContext()
}

// MARK: - Core Data stack

lazy var persistentContainer: NSPersistentContainer = {
    /*
     The persistent container for the application. This implementation
     creates and returns a container, having loaded the store for the
     application to it. This property is optional since there are legitimate
     error conditions that could cause the creation of the store to fail.
     */

// SEE BELOW LINE OF CODE WHERE THE 'name' IS SET AS THE FILE NAME (SampleData) FOR THE CONTAINER

let container = NSPersistentContainer(name: "SampleData")
    container.loadPersistentStores(completionHandler: { (storeDescription, error) in
        if let error = error as NSError? {
            // Replace this implementation with code to handle the error appropriately.
            // fatalError() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.

/*
             Typical reasons for an error here include:
             * The parent directory does not exist, cannot be created, or disallows writing.
             * The persistent store is not accessible, due to permissions or data protection when the device is locked.
             * The device is out of space.
             * The store could not be migrated to the current model version.
             Check the error message to determine what the actual problem was.
             */
            fatalError("Unresolved error \(error), \(error.userInfo)")
        }
    })
    return container
}()

// MARK: - Core Data Saving support

func saveContext () {
    let context = persistentContainer.viewContext
    if context.hasChanges {
        do {
            try context.save()
        } catch {
            // Replace this implementation with code to handle the error appropriately.
            // fatalError() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
            let nserror = error as NSError
            fatalError("Unresolved error \(nserror), \(nserror.userInfo)")
        }
    }
}

</code>
  </pre>
  <P>
    的<strong>
      第4步：
    </强>
     向模型添加实体和属性
  </p>
  <P>
    a）添加实体

<a href="https://i.stack.imgur.com/B9cju.png" rel="noreferrer">
      <img src =“https://i.stack.imgur.com/B9cju.png”alt =“在此处输入图片说明”/>
    </A>
  </p>
  <P>
    b）添加属性

<a href="https://i.stack.imgur.com/5V2v7.png" rel="noreferrer">
      <img src =“https://i.stack.imgur.com/5V2v7.png”alt =“在此处输入图片说明”/>
    </A>
  </p>
  <P>
    的<strong>
      第5步：
    </强>
     保存数据
  </p>
   <pre>
    <code>
      func saveItem(itemToSave: String){
    let context = (UIApplication.shared.delegate as! AppDelegate).persistentContainer.viewContext

//**Note:** Here we are providing the entityName **`Entity`** that we have added in the model
    let entity = NSEntityDescription.entity(forEntityName: "Entity", in: context)
    let myItem = NSManagedObject(entity: entity!, insertInto: context)

myItem.setValue(itemToSave, forKey: "item")
    do {
        try context.save()
    }
    catch{
        print("There was an error in saving data")
    }
}

</code>
  </pre>
  <P>
    的<strong>
      第5步：
    </强>
     检索数据
  </p>
   <pre>
    <code>
      override func viewWillAppear(_ animated: Bool) {
    // Obtaining data from model
    let context = (UIApplication.shared.delegate as! AppDelegate).persistentContainer.viewContext
    let fetchRequest = NSFetchRequest<NSFetchRequestResult>(entityName: "Entity")

do {
        let results = try context.fetch(fetchRequest)
        let obtainedResults = results as! [NSManagedObject]
        let firstResult = obtainedResults[0]
        let myValue = firstResult.value(forKey: "item")

print("myValue: \(myValue)")
    } catch {
        print("Error")
    }
}

</code>
  </pre>
</DIV>

5# 机器设备维修 | 2019-08-31 10-32

<div class =“post-text”itemprop =“text”>
   <pre>
    <code>
        - (void)viewDidLoad {
  [super viewDidLoad];
  // Do any additional setup after loading the view.
   if (self.userData) {
    [self.nameTxt setText:[self.userData valueForKey:@"name"]];
    [self.mobileTxt setText:[self.userData 
     valueForKey:@"mobileNumber"]];
    [self.emailIdTxt setText:[self.userData valueForKey:@"email"]];
    [self.imgView setImage:[UIImage imageWithData:[self.userData 
     valueForKey:@"imageView"]]];    }
        }

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

- (BOOL)textFieldShouldReturn:(UITextField *)textField
  {
   [textField resignFirstResponder];
return YES;
 }
  /*
  #pragma mark - Navigation

- (IBAction)browseBtn:(id)sender
   {

UIImagePickerController *imgpic =[[UIImagePickerController      
     alloc]init];     
  imgpic .delegate =self;
 imgpic .sourceType =UIImagePickerControllerSourceTypePhotoLibrary;
[self presentViewController:imgpic animated:YES completion:nil];

}
 -(void)imagePickerController:(UIImagePickerController *)picker 
 didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info
 {
  UIImage *choose = info[UIImagePickerControllerOriginalImage];
self.imgView.image=choose;
[picker dismissViewControllerAnimated:YES completion:nil];
}

- (IBAction)saveBtnClick:(id)sender {

NSManagedObjectContext *context = [self managedObjectContext];

if (self.userData) {
    // Update existing data
    [self.userData setValue:self.nameTxt.text forKey:@"name"];
    [self.userData setValue:self.mobileTxt.text 
     forKey:@"mobileNumber"];        
   [self.userData setValue:self.emailIdTxt.text forKey:@"email"];

UIImage *sampleimage = _imgView.image;
    NSData *dataImage = UIImageJPEGRepresentation(sampleimage, 1.0);
            [self.userData setValue:dataImage forKey:@"imageView"];

} else {
    // Create a new data
    NSManagedObject *newDevice = [NSEntityDescription 
     insertNewObjectForEntityForName:@"Details" 
     inManagedObjectContext:context];
    [newDevice setValue:self.nameTxt.text forKey:@"name"];
    [newDevice setValue:self.mobileTxt.text forKey:@"mobileNumber"];
    [newDevice setValue:self.emailIdTxt.text forKey:@"email"];
    UIImage *sampleimage = _imgView.image;
    NSData *dataImage = UIImageJPEGRepresentation(sampleimage, 1.0);

[newDevice setValue:dataImage forKey:@"imageView"];

}

NSError *error = nil;
 // Save the object to persistent store
 if (![context save:&error]) {
    NSLog(@"Can't Save! %@ %@", error, [error localizedDescription]);
 }

[self dismissViewControllerAnimated:YES completion:nil];
 }
   @end

</code>
  </pre>
  <P>
    。H
  </p>
   <pre>
    <code>
       #import <UIKit/UIKit.h>
#import <CoreData/CoreData.h>

@interface DetailViewController :
 UIViewController<UITextFieldDelegate,UINavigationControllerDelegate,            
     UIIma
    gePickerControllerDelegate>
         @property (weak, nonatomic) IBOutlet UITextField *nameTxt;
  @property (weak, nonatomic) IBOutlet UITextField *mobileTxt;
 @property (weak, nonatomic) IBOutlet UITextField *emailIdTxt;
  @property (weak, nonatomic) IBOutlet UIImageView *imgView;
 - (IBAction)browseBtn:(id)sender;
 - (IBAction)saveBtnClick:(id)sender;
@property (strong,nonatomic) NSManagedObject *userData;

@end

</code>
  </pre>
</DIV>

6# 绵绵 | 2019-08-31 10-32

<div class =“post-text”itemprop =“text”>
  <P>
    //在Swift 2.2中，您可以在不更改AppDelegate文件的情况下执行以下操作。
  </p>
  <OL>
    <LI>
      项目 - ＆gt;目标 - ＆gt;链接的框架和库
现在添加一个新框架（点击+）'CoreData'
    </LI>
    <LI>
      文件 - ＆gt;新文件 - ＆gt; CoreData-＆gt; DataModel
将其命名为A.xcdatamodelid
    </LI>
    <LI>
      在A.xcdatamodelid中创建新的enitity（单击实体+）
将其命名为Bc，并在右侧的检查器窗口中将其类设置为“Bc”。
    </LI>
    <LI>
      现在向实体添加属性（单击属性+），为例如：name添加一个属性，将其类型添加为String。
    </LI>
    <LI>
      现在编辑 - >创建NSManagedObject子类 - ＆gt;单击弹出窗口旁边的下一步 - >再次点击>  - >然后单击创建。
将创建两个新文件1.一个名为Bc.swift的新类和一个名为Bc + coredataproperties.swift的扩展名。
    </LI>
    <LI>
      <P>
        File-＆gt; new file-＆gt; ios-＆gt; cocoa Touch class  - ＆gt;将其子类设置为NSObject-＆gt;将其命名为DataController.swift
文件里面包括
///
      </p>
      <P>
        导入UIKit
导入CoreData
class DataController：NSObject {
      </p>
       <pre>
        <code>
          var managedObjectContext: NSManagedObjectContext

override  init() {
    // This resource is the same name as your xcdatamodeld contained in your project.
    guard let modelURL = NSBundle.mainBundle().URLForResource("A", withExtension:"momd") else {
        fatalError("Error loading model from bundle")
    }
    // The managed object model for the application. It is a fatal error for the application not to be able to find and load its model.
    guard let mom = NSManagedObjectModel(contentsOfURL: modelURL) else {
        fatalError("Error initializing mom from: \(modelURL)")
    }
    let psc = NSPersistentStoreCoordinator(managedObjectModel: mom)
    self.managedObjectContext = NSManagedObjectContext(concurrencyType: .MainQueueConcurrencyType)
    self.managedObjectContext.persistentStoreCoordinator = psc

let urls = NSFileManager.defaultManager().URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask)
    let docURL = urls[urls.endIndex-1]
    /* The directory the application uses to store the Core Data store file.
    This code uses a file named "A.sqlite" in the application's documents directory.
    */
    let storeURL = docURL.URLByAppendingPathComponent("A.sqlite")
    do {
        try psc.addPersistentStoreWithType(NSSQLiteStoreType, configuration: nil, URL: storeURL, options: nil)
    } catch {
        fatalError("Error migrating store: \(error)")
    }

}

</code>
      </pre>
      <P>
        }
      </p>
    </LI>
  </醇>
  <P>
    //////
  </p>
  <ol start =“7”>
    <LI>
      现在在viewcontroller文件中，您可以使用两种方法访问数据库。
重要说明：在viewController中包含该语句
        “导入CoreData”
一个。调用seed（） - ＆gt;将值插入db / entity
湾call fetch（） - ＆gt;从db / entity获取值
    </LI>
  </醇>
  <P>
    ///////种子（） - ＆GT; DEF
  </p>
   <pre>
    <code>
      func seedPerson() {

// create an instance of our managedObjectContext
        let moc = DataController().managedObjectContext

// we set up our entity by selecting the entity and context that we're targeting
        let entity = NSEntityDescription.insertNewObjectForEntityForName("Bc", inManagedObjectContext: moc) as! Bc

// add our data
        entity.setValue("Meera", forKey: "name")

// we save our entity
        do {
            try moc.save()
        } catch {
            fatalError("Failure to save context: \(error)")
        }
    }

</code>
  </pre>
  <P>
    // fetch（）def
  </p>
   <pre>
    <code>
      func fetch() {
        let moc = DataController().managedObjectContext
        let personFetch = NSFetchRequest(entityName: "Bc")

do {
            let fetchedPerson = try moc.executeFetchRequest(personFetch) as! [Bc]
            print(fetchedPerson.first!.name!)

} catch {
            fatalError("Failed to fetch person: \(error)")
        }
    }

</code>
  </pre>
</DIV>

7# 樱花弄๑•ั็•็ | 2019-08-31 10-32

8# 子阳 | 2019-08-31 10-32

<div class =“post-text”itemprop =“text”>
  <P>
    只是为了阐述您实际需要执行的所有步骤，以将Core Data添加到以前没有它的项目中：
  </p>
  <H1>
    第1步：添加框架
  </H1>
  <P>
    点击您的应用目标（在左侧窗格中，它的顶部图标带有您应用的名称），然后转到“构建阶段”标签，然后点击“链接二进制文件库”，点击底部的小“+”然后找'CoreData.framework'并将其添加到您的项目中
  </p>
  <P>
    然后使用以下方法在您需要的所有对象上导入coredata（非性感方式）：
  </p>
  <P>
    的<strong>
      迅速
    </强>
  </p>
   <pre>
    <code>
      import CoreData

</code>
  </pre>
  <P>
    的<strong>
      目标C.
    </强>
  </p>
   <pre>
    <code>
      #import <CoreData/CoreData.h>

</code>
  </pre>
  <P>
    或者在.pch文件中添加常见导入下面的导入（更加性感），如下所示：
  </p>
   <pre>
    <code>
      #ifdef __OBJC__
    #import <UIKit/UIKit.h>
    #import <Foundation/Foundation.h>
    #import <CoreData/CoreData.h>
#endif

</code>
  </pre>
  <H1>
    第2步：添加数据模型
  </H1>
  <P>
    要添加.xcdatamodel文件，请右键单击/按住Control键并单击右侧窗格中的文件（如在“资源”文件夹中保存），然后选择“添加新文件”，在选择文件类型时单击“核心数据”选项卡，然后单击“确定”。数据模型'，给它一个名称，然后单击下一步和完成，它将把它添加到您的项目中。当您单击此Model对象时，您将看到用您想要的任何关系将实体添加到项目的界面。
  </p>
  <H1>
    第3步：更新App Delegate
  </H1>
  <P>
    在
    的<strong>
      迅速
    </强>
     在AppDelegate.swift上
  </p>
   <pre>
    <code>
      //replace the previous version of applicationWillTerminate with this
func applicationWillTerminate(application: UIApplication) {
    // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
    // Saves changes in the application's managed object context before the application terminates.
    self.saveContext()
}

func saveContext () {
    var error: NSError? = nil
    let managedObjectContext = self.managedObjectContext
    if managedObjectContext != nil {
        if managedObjectContext.hasChanges && !managedObjectContext.save(&error) {
            // Replace this implementation with code to handle the error appropriately.
            // abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
            //println("Unresolved error \(error), \(error.userInfo)")
            abort()
        }
    }
}

// #pragma mark - Core Data stack

// Returns the managed object context for the application.
// If the context doesn't already exist, it is created and bound to the persistent store coordinator for the application.
var managedObjectContext: NSManagedObjectContext {
    if !_managedObjectContext {
        let coordinator = self.persistentStoreCoordinator
        if coordinator != nil {
            _managedObjectContext = NSManagedObjectContext()
            _managedObjectContext!.persistentStoreCoordinator = coordinator
        }
    }
    return _managedObjectContext!
}
var _managedObjectContext: NSManagedObjectContext? = nil

// Returns the managed object model for the application.
// If the model doesn't already exist, it is created from the application's model.
var managedObjectModel: NSManagedObjectModel {
    if !_managedObjectModel {
        let modelURL = NSBundle.mainBundle().URLForResource("iOSSwiftOpenGLCamera", withExtension: "momd")
        _managedObjectModel = NSManagedObjectModel(contentsOfURL: modelURL)
    }
    return _managedObjectModel!
}
var _managedObjectModel: NSManagedObjectModel? = nil

// Returns the persistent store coordinator for the application.
// If the coordinator doesn't already exist, it is created and the application's store added to it.
var persistentStoreCoordinator: NSPersistentStoreCoordinator {
    if !_persistentStoreCoordinator {
        let storeURL = self.applicationDocumentsDirectory.URLByAppendingPathComponent("iOSSwiftOpenGLCamera.sqlite")
        var error: NSError? = nil
        _persistentStoreCoordinator = NSPersistentStoreCoordinator(managedObjectModel: self.managedObjectModel)
        if _persistentStoreCoordinator!.addPersistentStoreWithType(NSSQLiteStoreType, configuration: nil, URL: storeURL, options: nil, error: &error) == nil {
            /*
            Replace this implementation with code to handle the error appropriately.
            abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
            Typical reasons for an error here include:
            * The persistent store is not accessible;
            * The schema for the persistent store is incompatible with current managed object model.
            Check the error message to determine what the actual problem was.
            If the persistent store is not accessible, there is typically something wrong with the file path. Often, a file URL is pointing into the application's resources directory instead of a writeable directory.
            If you encounter schema incompatibility errors during development, you can reduce their frequency by:
            * Simply deleting the existing store:
            NSFileManager.defaultManager().removeItemAtURL(storeURL, error: nil)
            * Performing automatic lightweight migration by passing the following dictionary as the options parameter:
            [NSMigratePersistentStoresAutomaticallyOption: true, NSInferMappingModelAutomaticallyOption: true}
            Lightweight migration will only work for a limited set of schema changes; consult "Core Data Model Versioning and Data Migration Programming Guide" for details.
            */
            //println("Unresolved error \(error), \(error.userInfo)")
            abort()
        }
    }
    return _persistentStoreCoordinator!
}
var _persistentStoreCoordinator: NSPersistentStoreCoordinator? = nil

// #pragma mark - Application's Documents directory

// Returns the URL to the application's Documents directory.
var applicationDocumentsDirectory: NSURL {
    let urls = NSFileManager.defaultManager().URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask)
    return urls[urls.endIndex-1] as NSURL
}

</code>
  </pre>
  <P>
    在
    的<strong>
      目标C.
    </强>
     确保将这些对象添加到AppDelegate.h中
  </p>
   <pre>
    <code>
       @property (nonatomic, retain, readonly) NSManagedObjectModel *managedObjectModel;
 @property (nonatomic, retain, readonly) NSManagedObjectContext *managedObjectContext;
 @property (nonatomic, retain, readonly) NSPersistentStoreCoordinator *persistentStoreCoordinator;

- (NSURL *)applicationDocumentsDirectory; // nice to have to reference files for core data

</code>
  </pre>
  <P>
    像这样合成AppDelegate.m中的前一个对象：
  </p>
   <pre>
    <code>
      @synthesize managedObjectContext = _managedObjectContext;
@synthesize managedObjectModel = _managedObjectModel;
@synthesize persistentStoreCoordinator = _persistentStoreCoordinator;

</code>
  </pre>
  <P>
    然后将这些方法添加到AppDelegate.m（确保将您添加的模型的名称放在显示的位置）：
  </p>
   <pre>
    <code>
      - (void)saveContext{
    NSError *error = nil;
    NSManagedObjectContext *managedObjectContext = self.managedObjectContext;
    if (managedObjectContext != nil) {
        if ([managedObjectContext hasChanges] && ![managedObjectContext save:&error]) {
            NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
            abort();
        }
    }
}

- (NSManagedObjectContext *)managedObjectContext{
    if (_managedObjectContext != nil) {
        return _managedObjectContext;
    }

NSPersistentStoreCoordinator *coordinator = [self persistentStoreCoordinator];
    if (coordinator != nil) {
        _managedObjectContext = [[NSManagedObjectContext alloc] init];
        [_managedObjectContext setPersistentStoreCoordinator:coordinator];
    }
    return _managedObjectContext;
}

- (NSManagedObjectModel *)managedObjectModel{
    if (_managedObjectModel != nil) {
        return _managedObjectModel;
    }
    NSURL *modelURL = [[NSBundle mainBundle] URLForResource:@"NAMEOFYOURMODELHERE" withExtension:@"momd"];
    _managedObjectModel = [[NSManagedObjectModel alloc] initWithContentsOfURL:modelURL];
    return _managedObjectModel;
}

- (NSPersistentStoreCoordinator *)persistentStoreCoordinator
{
    if (_persistentStoreCoordinator != nil) {
        return _persistentStoreCoordinator;
    }

NSURL *storeURL = [[self applicationDocumentsDirectory] URLByAppendingPathComponent:@"NAMEOFYOURMODELHERE.sqlite"];

NSError *error = nil;
    _persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:[self managedObjectModel]];
    if (![_persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:storeURL options:nil error:&error]) {

NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
        abort();
    }

return _persistentStoreCoordinator;
}

#pragma mark - Application's Documents directory

// Returns the URL to the application's Documents directory.
- (NSURL *)applicationDocumentsDirectory{
    return [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] lastObject];
}

</code>
  </pre>
  <H1>
    第4步：将数据对象获取到需要数据的ViewControllers
  </H1>
  <P>
    的<strong>
      选项1.使用VC中的App Delegate的ManagedObjectContext（首选和更简单）
    </强>
  </p>
  <P>
    正如@ brass-kazoo所建议的那样 - 通过以下方式检索对AppDelegate及其managedObjectContext的引用：
  </p>
  <P>
    的<strong>
      迅速
    </强>
  </p>
   <pre>
    <code>
       let appDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
 appDelegate.managedObjectContext

</code>
  </pre>
  <P>
    的<strong>
      目标C.
    </强>
  </p>
   <pre>
    <code>
       [[[UIApplication sharedApplication] delegate] managedObjectContext];

</code>
  </pre>
  <P>
    在您的ViewController中
  </p>
  <P>
    的<strong>
      选项2.在VC中创建ManagedObjectContext并使其与AppDelegate（原始）中的AppDelegate匹配
    </强>
  </p>
  <P>
    <EM>
      仅显示Objective C的旧版本，因为更容易使用首选方法
    </EM>
  </p>
  <P>
    在ViewController.h中
  </p>
   <pre>
    <code>
      @property (nonatomic, retain) NSManagedObjectContext *managedObjectContext;

</code>
  </pre>
  <P>
    在ViewController.m中
  </p>
   <pre>
    <code>
      @synthesize managedObjectContext = _managedObjectContext;

</code>
  </pre>
  <P>
    在AppDelegate或创建ViewController的类中，将managedObjectContext设置为与AppDelegate相同
  </p>
   <pre>
    <code>
      ViewController.managedObjectContext = self.managedObjectContext;

</code>
  </pre>
  <P>
    如果你想使用Core Data的viewcontroller是一个FetchedResultsController，那么你需要确保这些东西在你的ViewController.h中
  </p>
   <pre>
    <code>
      @interface ViewController : UIViewController <NSFetchedResultsControllerDelegate> {
  NSFetchedResultsController *fetchedResultsController;
  NSManagedObjectContext *managedObjectContext;
}

@property (nonatomic, retain) NSFetchedResultsController *fetchedResultsController;

</code>
  </pre>
  <P>
    这是在ViewController.m中
  </p>
   <pre>
    <code>
      @synthesize fetchedResultsController, managedObjectContext;

</code>
  </pre>
  <P>
    完成所有这些之后，您现在可以使用此managedObjectContext来运行CoreData良好所需的所有常用fetchRequests！请享用
  </p>
</DIV>

9# 哎？小查查 | 2019-08-31 10-32

<div class =“post-text”itemprop =“text”>
  <P>
    导入所有CoreData头文件
     <code>
      App_Prefix.pch
    </code>
    ，因此CoreData类将在整个项目中可用，因此您不必手动导入所需文件中的标题。
  </p>
  <P>
    所以打开Xcode并寻找一些类似的文件
     <code>
      App_Prefix.pch
    </code>
    ，默认情况下，它在
     <code>
      Other Sources
    </code>
     组。之后
     <code>
      UIKit
    </code>
     import语句，添加以下行：
  </p>
   <pre>
    <code>
      #import <CoreData/CoreData.h>

</code>
  </pre>
  <P>
    你应该准备好了。
  </p>
  <H2>
    Xcode 4
  </H2>
  <P>
    对于在Xcode 4中创建的项目，可以在中找到前缀文件
     <code>
      Supporting Files
    </code>
     项目导航器中的组。它被称为'
    <EM>
      项目名
    </EM>
    -Prefix.pch'默认情况下。
  </p>
  <H2>
    Xcode 6+
  </H2>
  <P>
    从Xcode 6开始，默认情况下不再包含预编译的头文件。这是因为引入了模块
    <a href="https://stackoverflow.com/a/24194968/171436">
      不需要使用预编译的头文件。
    </A>
     虽然仍然可以手动添加PCH文件以全局包含CoreData标头，但请考虑使用指定CoreData依赖关系
     <code>
      @import CoreData;
    </code>
    *在每个使用CoreData的文件中。这使得依赖性显而易见，更重要的是将来避免这个问题的问题。
  </p>
  <P>
    <子>
      *模块
      <a href="http://useyourloaf.com/blog/modules-and-precompiled-headers.html" rel="nofollow noreferrer">
        需要启用
      </A>
       为此工作。
    </子>
  </p>
</DIV>

10# 冷月如霜·胡狼 | 2019-08-31 10-32

11# 一瓶泡沫 | 2019-08-31 10-32