ios - 废弃的内存问题

Question

你能帮帮我吗，我的应用程序快完成了，我现在正在优化它，所以我正在使用 Instrument Allocations 工具，我在 View Controller 上遇到了问题，但我想不通了解为什么每次从主视图转到 detailedViewController 时内存都会增加。

这是似乎有问题的代码部分:

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

// Create and push a detail view controller.

    self.entriesDetailedViewController = [[EntriesDetailedViewController alloc]init];

Entry *selectedEntry = (Entry *)[[self fetchedResultsController] objectAtIndexPath:indexPath];

self.entriesDetailedViewController.entry = selectedEntry;

[self.navigationController pushViewController:self.entriesDetailedViewController animated:YES];
[self.entriesDetailedViewController release];
}

这里是 detailedViewController.h 的代码:

  #import <UIKit/UIKit.h>


  @class Entry;

 @interface EntriesDetailedViewController : UIViewController <UITextViewDelegate> {

//IBOutlet UIButton *createEntryButton;
IBOutlet UITextField *entryTextField1;
IBOutlet UITextView *entryTextField2;
IBOutlet UIBarButtonItem *textbodyBarButton;
IBOutlet UIBarButtonItem * catLabel;
IBOutlet UINavigationBar *entryNameToolBar;
IBOutlet UINavigationBar *textBodyToolBar;
IBOutlet UIImageView *reviewCheck;
IBOutlet UIImageView *textBackground;
IBOutlet UIBarButtonItem *reviewButton;
BOOL isChecked;

NSManagedObjectContext *managedObjectContext;


Entry *entry;

    }


 @property (nonatomic,retain) IBOutlet UITextField *entryTextField1;
 @property (nonatomic,retain) IBOutlet UITextView *entryTextField2;
 @property (nonatomic,retain) IBOutlet UIBarButtonItem *textbodyBarButton;
 @property (nonatomic,retain) IBOutlet UIBarButtonItem *catLabel;
 @property (nonatomic,retain) IBOutlet UINavigationBar *entryNameToolBar;
 @property (nonatomic,retain) IBOutlet UINavigationBar *textBodyToolBar;
 @property (nonatomic,retain) IBOutlet UIImageView *reviewCheck;
 @property (nonatomic,retain) IBOutlet UIBarButtonItem *reviewButton;
 @property BOOL isChecked;
 @property (nonatomic,retain) IBOutlet UIImageView *textBackground;

 @property (nonatomic,retain) NSManagedObjectContext *managedObjectContext;
 @property (nonatomic, retain) Entry *entry;


 - (void)setUpUndoManager;
 - (void)cleanUpUndoManager;
 - (void)textViewDidBeginEditing:(UITextView *)entryTextField2;
 - (void)textViewDidEndEditing:(UITextView  *)entryTextField2;
 - (void)saveContext;



 - (IBAction)dismisskeyboard;
 - (IBAction)dismissKeyboardfromTextView;
 - (IBAction) selectReview;


 @end

这是 detailedViewController.m :

  #import "EntriesDetailedViewController.h"
  #import "Entry.h"
  #import "TheLearningMachineAppDelegate.h"


  @implementation EntriesDetailedViewController

  @synthesize entryTextField1,entryTextField2,textbodyBarButton,managedObjectContext,catLabel, entryNameToolBar,textBodyToolBar, reviewCheck,reviewButton,isChecked,textBackground, entry, undoManager;


  #pragma mark -
  #pragma mark View lifecycle


  - (void)viewWillAppear:(BOOL)animated {

  }

  - (void)viewDidLoad {
      [super viewDidLoad];

  // Configure the title, title bar, and table view.

      self.title = @"Consultation";

    UIBarButtonItem *rightButton = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemSave target:self action:@selector(save:)]; 
self.navigationItem.rightBarButtonItem = rightButton; 
[rightButton release];

[self setUpUndoManager];

self.entryTextField1.text = self.entry.entryname;
self.entryTextField2.font = [UIFont fontWithName:@"Helvetica" size:17.0];
self.entryTextField2.text = self.entry.textbody;
self.catLabel.title = self.entry.category;
[self.entryTextField2 setFrame:CGRectMake(24, 56, 273, 140)];

self.textBackground.image = [UIImage imageNamed:@"alert_background.png"];
[self.textBackground setFrame:CGRectMake(0,46,312,140)];



  //Initializing a kind of checkBox button

if ([self.entry.active boolValue] == YES) {

    self.reviewCheck.image = [UIImage imageNamed:@"checkedwhitesquare.png"];

    self.isChecked = YES;
}

else {

    self.reviewCheck.image = [UIImage imageNamed:@"UncheckedWhiteSquare.png"];

    self.isChecked = NO;

}

  }


  - (IBAction) selectReview {

      if (isChecked==NO){
        self.reviewCheck.image = [UIImage imageNamed:@"checkedwhitesquare.png"];
    self.isChecked = YES;
    [self.entry setValue:[NSNumber numberWithBool:YES] forKey:@"active"];
    [self performSelector: @selector(save:)];

}
else {

    self.reviewCheck.image = [UIImage imageNamed:@"UncheckedWhiteSquare.png"];

    self.isChecked = NO;
    [self.entry setValue:[NSNumber numberWithBool:YES] forKey:@"active"];
    [self performSelector: @selector(save:)];

}

  }



  - (void)textViewDidBeginEditing:(UITextView  *)entryTextField2{
[self.navigationController setNavigationBarHidden:YES animated:YES];
self.entryNameToolBar.hidden =YES; 
self.textBodyToolBar.hidden =NO;
self.textbodyBarButton.style =UIBarButtonItemStyleBordered;
self.textbodyBarButton.title =@"Terminer la saisie";
[self.entryTextField2 setFrame:CGRectMake(24, 50, 273, 140)];
[self.textBackground setFrame:CGRectMake(0,46,312,140)];
  }

  - (IBAction)textViewDidEndEditing: (UITextView  *)entryTextField2{
      [self.navigationController setNavigationBarHidden:NO animated:YES];
      self.entryNameToolBar.hidden =NO;
      self.textBodyToolBar.hidden =YES;
      [self.entryTextField2 setFrame:CGRectMake(24, 50, 273, 140)];
      [self.textBackground setFrame:CGRectMake(0,46,312,140)];
      self.textbodyBarButton.style =UIBarButtonItemStyleDone;
      self.textbodyBarButton.title =@"Corps de texte";  

  }

  - (IBAction)dismisskeyboard{

[self.entryTextField1 resignFirstResponder];
  }

  - (IBAction)dismissKeyboardfromTextView{

[self.entryTextField2 resignFirstResponder];

  }

  - (void)saveContext {

      NSError *error = nil;
      if (self.managedObjectContext != nil) {
          if ([self.managedObjectContext hasChanges] && ![self.managedObjectContext save:&error]) {

        NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Erreur" 
        message:@"blabla" delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
        [alert show];
        [alert release];


        abort();

          } 
      }
  }  


  - (IBAction)save:(id)sender {

      // if there's text in textfield1 and textfield2 and a category has been set 
      if (([self.entryTextField1.text length]!= 0) && ([self.entryTextField2.text length]!= 0) && ([self.catLabel.title length]!= 0)){ 

    [self.entry setValue:self.entryTextField1.text forKey:@"entryname"];
    [self.entry setValue:self.entryTextField2.text forKey:@"textbody"];
    [self.entry setValue:self.catLabel.title forKey:@"category"];

    if (self.isChecked == YES) {
        [self.entry setValue:[NSNumber numberWithBool:YES]forKey:@"active"];
    }
    else {

        [self.entry setValue:[NSNumber numberWithBool:NO] forKey:@"active"];
    }

    [self.entry setValue:[NSNumber numberWithBool:NO] forKey:@"editable"];

    //save
    NSError *error;
    [self.managedObjectContext save:&error];
    [self saveContext];

    //Return to mainview
    [self.navigationController popViewControllerAnimated:YES];
    [self.entry release];
    //self.entry =nil;
}

else {

    if([self.entryTextField1.text length] ==0){

        UIAlertView *alert =[[UIAlertView alloc] 
                             initWithTitle:@"Oooops..." 
                             message:@"Your entry has no name" 
                             delegate:nil 
                             cancelButtonTitle: @"ok" 
                             otherButtonTitles:nil];
        [alert show];
        [alert release];

    }
    else {

        if ([self.entryTextField2.text length]==0){

            UIAlertView *alert =[[UIAlertView alloc] initWithTitle:@"Oooops..." message:@"Your list is empty" delegate:nil cancelButtonTitle: @"ok" otherButtonTitles:nil];
            [alert show];
            [alert release];

        }
        else {

            if ([self.catLabel.title length]==0){

                UIAlertView *alert =[[UIAlertView alloc] initWithTitle:@"Oooops..." message:@"You need to choose a category for this list first." delegate:nil cancelButtonTitle: @"ok" otherButtonTitles:nil];
                [alert show];
                [alert release];

                  }
              }

          }
      }
   }


  - (void)setEditing {
  //    [super setEditing:editing animated:animated];
  }




  #pragma mark -
  #pragma mark Undo support

  - (void)setUpUndoManager {

    if (self.entry.managedObjectContext.undoManager == nil) {

    NSUndoManager *undoMgr = [[NSUndoManager alloc] init];
    [undoMgr setLevelsOfUndo:1];
    self.entry.managedObjectContext.undoManager = undoMgr;
    [undoMgr release];


    }

    // Register as an observer of the entry's context's undo manager.
    NSUndoManager *entryUndoManager = self.entry.managedObjectContext.undoManager;
NSNotificationCenter *dnc = [NSNotificationCenter defaultCenter];
    [dnc addObserver:self selector:@selector(undoManagerDidUndo:) name:NSUndoManagerDidUndoChangeNotification object:entryUndoManager];
    [dnc addObserver:self selector:@selector(undoManagerDidRedo:) name:NSUndoManagerDidRedoChangeNotification object:entryUndoManager];


  }


  - (void)cleanUpUndoManager {

      // Remove self as an observer.
      [[NSNotificationCenter defaultCenter] removeObserver:self];

      if (self.entry.managedObjectContext.undoManager == undoManager) {
          self.entry.managedObjectContext.undoManager = nil;
          self.undoManager = nil;
      }       
  }


  - (NSUndoManager *)undoManager {
      return self.entry.managedObjectContext.undoManager;
  }


  - (void)undoManagerDidUndo:(NSNotification *)notification {

  }


  - (void)undoManagerDidRedo:(NSNotification *)notification {

  }

  - (BOOL)canBecomeFirstResponder {
      return YES;
  }


  - (void)viewDidAppear:(BOOL)animated {
      [super viewDidAppear:animated];
      [self becomeFirstResponder];
  }


  - (void)viewWillDisappear:(BOOL)animated {
      [super viewWillDisappear:animated];
      [self resignFirstResponder];
  }

- (void)viewDidUnload {

// Release any properties that are loaded in viewDidLoad or can be recreated lazily.


self.entryTextField1 =nil;
self.entryTextField2 = nil;
self.catLabel = nil;
self.entryNameToolBar = nil;
self.textBodyToolBar = nil;
self.reviewCheck = nil;
self.textBackground = nil;
self.reviewButton = nil;
self.entry = nil;
self.navigationItem.rightBarButtonItem = nil;
[self cleanUpUndoManager];
self.entry.managedObjectContext.undoManager = nil;


}

  - (void)dealloc {

[entryTextField1 release], entryTextField1 = nil;
[entryTextField2 release], entryTextField2 = nil;
[catLabel release], catLabel = nil;
[entryNameToolBar release], entryNameToolBar = nil;
[textBodyToolBar release], textBodyToolBar = nil;
[reviewCheck release], reviewCheck = nil;
[textBackground release], textBackground = nil;
[reviewButton release], reviewButton = nil;
[self cleanUpUndoManager];
[entry.managedObjectContext.undoManager release],  
     entry.managedObjectContext.undoManager = nil;
[entry release],entry = nil;
[managedObjectContext release];


[super dealloc];
}

对不起，我知道这是一段很长的代码，但我不知所措。请帮助我。

按照你们的建议，我做了以下修改:

我还更改了代码的 viewDidUnload 和 Dealloc 部分，现在看起来像这样:

我不太明白 release + nil 的概念，也不明白在 dealloc 中调用 [self.object release] 和 [object release] 与在 viewDidUnload 中调用 self.object = nil 之间的区别。

Answer 1

每次您分配一个新的 EntriesDetailedViewController 时，您应该预料到您的内存使用量会增加。我假设你的意思是当你释放它时你的内存不会下降？您可能没有在 -[EntriesDetailedViewController dealloc] 中正确发布某些内容。

请注意，与其每次都生成一个新的 EntriesDetailedViewController，不如在您第一次需要它时创建一个，然后继续使用 setEntry 重新配置它:。您已经设置了 ivar 来保存 View Controller ；不妨利用它。