UI 冻结与神奇的记录

Posted 2023-03-04

【中文标题】UI 冻结与神奇的记录

【英文标题】：UI Freeze with Magical Record

【发布时间】：2012-10-22 00:22:10

【问题描述】：

大家好，我是 Riccardo，我是一名独立开发者！

我开始用objective-c编程的次数并不多，而且我还是个新手！ :D

我开始学习 Core Data，一切都很顺利，直到我遇到并发问题！ 使用 Core Data，我的应用程序在保存操作期间继续阻塞，因此我在谷歌上搜索了具有背景上下文的核心数据，并找到了 Magical Record。

通过 Magical Record，我大大降低了代码的复杂性 :) 但是我还有一个问题，我阅读了有关 Magical Record 的所有内容，我尝试使用不同的方法修复它，但 UI 冻结仍然存在 :( 所以我不知道如何修复它......

虽然我认为所有方法都存在问题（查看冻结 UI），但列出的 4 种方法中有 3 种非常快，因此无法察觉。 唯一存在巨大问题并且您实际上可以注意到冻结的方法是这个 -->

(void) persistAppsFromArray: (NSArray *) arrayOfApps inResearch: (NSDictionary *) info;

我采用一个数组来创建所有应用程序对象，并在我将这些应用程序关联到研究之后（在获取研究后，我使用字典创建谓词）。

这是我的代码。它实际上是一个管理核心数据的整个类。 我不在调用这些方法的类中使用队列或线程，所以我认为这里有一些需要修复的地方：-/

提前谢谢你:)

#import "CoreDataHelper.h"
#import "CoreData+MagicalRecord.h"


@implementation CoreDataHelper

#pragma mark - Research creator helper

+ (ResearchType *) fetchResearchWithDictionary: (NSDictionary *) info 

// Fetch
// predicates for fetch
NSPredicate * predicateCategory = [NSPredicate predicateWithFormat:@"researchCategory = %@" , [info objectForKey: @"Category"]];
NSPredicate * predicateType = [NSPredicate predicateWithFormat:@"researchType = %@" , [info objectForKey: @"Type"]];
 NSPredicate * predicatePrefix = [NSPredicate predicateWithFormat:@"researchPrefix = %@" , [info objectForKey: @"Prefix"]];

 NSArray * predicates = [NSArray arrayWithObjects: predicateCategory, predicateType, predicatePrefix, nil];

        // create the composite predicate
        NSPredicate * predicateComposito = [NSCompoundPredicate andPredicateWithSubpredicates:predicates];

    // obtain the result
    // Passo la ricerca al brain
   return [ResearchType MR_findFirstWithPredicate: predicateComposito];

---

   + (void)updateResearchWithDictionary:(NSDictionary *) info withCompletionBlock:(completion_block)updatedResearch 

    // Get the context
    NSManagedObjectContext *localContext    = [NSManagedObjectContext MR_context];

    // predicates
    NSPredicate * predicateCategory = [NSPredicate predicateWithFormat:@"researchCategory = %@" , [info objectForKey: @"Category"]];
    NSPredicate * predicateType = [NSPredicate predicateWithFormat:@"researchType = %@" , [info objectForKey: @"Type"]];
    NSPredicate * predicatePrefix = [NSPredicate predicateWithFormat:@"researchPrefix = %@" , [info objectForKey: @"Prefix"]];

    NSArray * predicates = [NSArray arrayWithObjects: predicateCategory, predicateType, predicatePrefix, nil];

    // composite predicate
    NSPredicate * predicateComposito = [NSCompoundPredicate andPredicateWithSubpredicates:predicates];

// create research object 
    ResearchType *research = [ResearchType MR_findFirstWithPredicate: predicateComposito inContext:localContext];



// new properties
    research.researchDate      = [info objectForKey:@"Research Date"];
    research.researchLimit     = [info objectForKey:@"Limit"];
    //research.apps              =  nil;

  [localContext MR_saveInBackgroundCompletion:^

      updatedResearch(research);

  ];
 

---

   + (void) persistResearchWithDictionary: (NSDictionary *) info withCompletionBlock:(completion_block)savedResearch 

// Get the context
NSManagedObjectContext *localContext    = [NSManagedObjectContext MR_context];

// Create a new Person in the current thread context
ResearchType * research   = [ResearchType MR_createInContext:localContext];

// Set properties
research.researchCategory    = [info objectForKey:   @"Category"];
research.researchPrefix      = [info objectForKey:   @"Prefix"];
research.researchCategoryUrl = [info objectForKey:   @"Category Code Url"];
research.researchType        = [info objectForKey:   @"Type"];


research.researchCountry     = [info objectForKey:   @"Country"];
research.researchCountryCode = [info objectForKey:   @"Country Code"];
research.researchDate        = [info objectForKey:   @"Research Date"];
research.researchDevice      = [info objectForKey:   @"Device"];
research.researchLimit       = [info objectForKey:   @"Limit"];

// Save changes
 [localContext MR_saveInBackgroundCompletion:^

   savedResearch(research);
 ];

 

---

    + (void) persistAppsFromArray: (NSArray *) arrayOfApps inResearch: (NSDictionary *) info  


// Get the local context
    NSManagedObjectContext *localContext    = [NSManagedObjectContext MR_context];

 [localContext MR_saveInBackgroundCompletion:^


     // predicates
     NSPredicate * predicateCategory = [NSPredicate predicateWithFormat:@"researchCategory = %@" , [info objectForKey: @"Category"]];
     NSPredicate * predicateType = [NSPredicate predicateWithFormat:@"researchType = %@" , [info objectForKey: @"Type"]];
     NSPredicate * predicatePrefix = [NSPredicate predicateWithFormat:@"researchPrefix = %@" , [info objectForKey: @"Prefix"]];

     NSArray * predicates = [NSArray arrayWithObjects: predicateCategory, predicateType, predicatePrefix, nil];

     // Composite predicate
     NSPredicate * predicateComposito = [NSCompoundPredicate andPredicateWithSubpredicates:predicates];

     ResearchType * researchBgContext = [ResearchType MR_findFirstWithPredicate: predicateComposito];

     for (NSDictionary * info in arrayOfApps) 

         AppInDb * app             = [AppInDb MR_createEntity];

         app.appName                  = [info objectForKey: @"App Name"];
         app.appItunesLink            = [info objectForKey: @"iTunes Link"];
         app.appBundleID              = [info objectForKey: @"Bundle ID"];
         app.appID                    = [info objectForKey: @"ID"];
         app.appPriceLabel            = [info objectForKey: @"Price Label"];
         app.appReleaseDate           = [info objectForKey: @"Release Date String"];
         app.appIconImageLink         = [info objectForKey: @"Image Link 100"];
         app.appDeveloperPageLink     = [info objectForKey: @"Developer Page Link"];
         app.appDeveloper             = [info objectForKey: @"Developer"];
         app.appRights                = [info objectForKey: @"Rights"];
         app.appDescription           = [info objectForKey: @"App Description"];
         app.appCategory              = [info objectForKey: @"App Category"];
         app.appCategoryNumber        = [info objectForKey: @"Category Number For Url"];


         // adding app to the related research (one to many relationship)
         [researchBgContext addAppsObject:app];



           
       ];

     

【参考方案1】：

试试这个方法：

[MagicalRecord saveInBackgroundWithBlock:^(NSManagedObjectContext *localContext)block ];

您可以使用许多其他方法，但这应该会给您一个良好的开端。 MagicalRecord 将为您创建上下文，一切都发生在后台线程上。它还会自动保存到父上下文。

我推荐阅读这篇很棒的文章：Core Data and Threads, Without the Headache，作者是 MagicalRecord 背后的人 Saul Mora。这是一本很棒的读物，它告诉您 MagicalRecord 的许多优点。

祝你好运！

【讨论】：

谢谢，我会尽量听从您的建议！ :)