UITableView fuite de classe personnalisée énorme

Question

J'utilise une classe personnalisée pour afficher des informations sur une vue de table. Le problème est que tant que je fais défiler la tableview fuit la mémoire ...

Je suppose que j'ai quelque chose de mal à ma classe.

S'il vous plaît consulter:

@interface Person : NSObject { 

NSString *name; 
NSString *surname; 
NSString *address; 
NSString *email; 

} 

@property (nonatomic, copy) NSString *name, *surname, *address, *email; 



@implementation Person 
@synthesize name, surname, address, email; 

-(id)init { 

[super init]; 
name = [[NSString alloc] init]; 
surname = [[NSString alloc] init]; 
address = [[NSString alloc] init]; 
email = [[NSString alloc] init]; 
return self; 
} 



- (void)dealloc 
{ 
[name release]; 
[surname release]; 
[address release]; 
[email release]; 
[super dealloc]; 
} 


#import "Person.h" 

@interface Group : NSObject { 

NSString *groupTitle; 
NSMutableArray *persons; 

} 

@property (readwrite, copy) NSString *groupTitle; 

- (void)addPerson:(Person *)person; 
- (void)removeAll; 
- (NSArray *)getPersons; 
- (int)PersonsCount; 

@end 




@implementation Group 
@synthesize groupTitle; 



-(id)init { 

[super init]; 
persons = [[NSMutableArray alloc] init]; 
return self; 
} 


-(void)addPerson:(Person *)person { 


[persons addObject:person]; 

} 

-(void)removeAll { 

[persons removeAllObjects]; 

} 

-(NSArray *) getPersons { 

return [persons copy]; 
[persons release]; 


} 

-(int)personsCount { 

return [persons count]; 

} 

-(void)dealloc { 

[groupTitle release], groupTitle = nil; 
[persons release], persons = nil; 
[super dealloc]; 
} 


@end 




- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { 

    ……. 


    Group *groupForRow = [[Group alloc] init]; 
    Person *personForRow = [[Person alloc] init]; 
    personForRow = [[groupForRow getPersons] objectAtIndex:indexPath.row]; 

    _personName = personForRow.name; 
    _personSurname = personForRow.surname; 
    _personAddress = personForRow.address; 
    _personEmail = personForRow.email; 


    [groupForRow release], groupForRow = nil; 
    [personForRow release], personForRow = nil; 

    ….. 

    return cell 

Answer 1

Quelques corrections (lire les commentaires):

@interface Person : NSObject { 
    NSString *name; 
    NSString *surname; 
    NSString *address; 
    NSString *email; 
} 

// copy is OK for strings... 
@property (nonatomic, copy) NSString *name, *surname, *address, *email; 

@end 


@implementation Person 

@synthesize name, surname, address, email; 

- (id)init { 
    if (self = [super init]) { 
     // There is no need to allocate the strings 
     // In addition, once you write 'name = [[NSStrin alloc] init];' you don't use the property. 
     // If you do want to use the property setter then you should write 'self.name = @"some string";' 
    } 
    return self; 
} 


- (void)dealloc { 
    [name release]; 
    [surname release]; 
    [address release]; 
    [email release]; 
    [super dealloc]; 
} 

@end 


#import "Person.h" 

@interface Group : NSObject { 
    NSString *groupTitle; 
    NSMutableArray *persons; 
} 

// Any special reason for "readwrite" instead of "nonatomic"? 
@property (readwrite, copy) NSString *groupTitle; 
// This property is more important than the string: 
@property (nonatomic, retain) NSMutableArray *persons; 

- (void)addPerson:(Person *)person; 
- (void)removeAll; 
- (NSArray *)getPersons; 
- (int)PersonsCount; 

@end 


@implementation Group 

@synthesize groupTitle, persons; 

- (id)init { 
    if (self = [super init]) { 
     // Use the autoreleased array instance ([NSMutableArray array]) and set it to the property setter that will retain the object: 
     self.persons = [NSMutableArray array]; 
    } 
    return self; 
} 


- (void)addPerson:(Person *)person { 
    // I prefer using properties (the "self." in the beginning) instead of the members directly... 
    [self.persons addObject:person]; 
} 

- (void)removeAll { 
    [self.persons removeAllObjects]; 
} 

// I think that this getter is unnecessary - use the property instead... 
- (NSArray *) getPersons { 
    // There is no need to copy 
    return [persons copy]; 
    // Don't you have a warning for this line? It is never executed 
    [persons release]; 
} 

- (int)personsCount { 
    return [self.persons count]; 
} 

- (void)dealloc { 
    [groupTitle release], groupTitle = nil;// The "groupTitle = nil" is unnecessary. 
    [persons release], persons = nil;// The "persons = nil" is unnecessary. 
    [super dealloc]; 
} 

@end 


- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { 

    ……. 


    Group *groupForRow = [[Group alloc] init];// Do you REALLY have to allocate this object each "cellForRowAtIndexPath"?? 
    Person *personForRow = [[Person alloc] init];// Get rid of the "= [[Person alloc] init]" - this is a leak (because of the next line) 
    personForRow = [[groupForRow getPersons] objectAtIndex:indexPath.row];// If you will use the property persons instead of the "getPersons" (that copies the array) then you will get rid of another leak 

    // What are these? 
    _personName = personForRow.name; 
    _personSurname = personForRow.surname; 
    _personAddress = personForRow.address; 
    _personEmail = personForRow.email; 

    // The " = nil" is unnecessary here... 
    [groupForRow release], groupForRow = nil;// If you won't allocate the group then you won't need this line... 
    [personForRow release], personForRow = nil;// NSZombie - you release object that you don't owe (do you have crashes, that you don't know why they are happen?) 

    ….. 

    return cell; 
} 

Answer 2

Il y a beaucoup de mal ici, s'il vous plaît plonger un peu dans Objective-C pour obtenir une bonne compréhension de l'utilisation de @property et @synthesize pour obtenir fonctionner correctement getter/méthodes setter .

Quant à votre fuite de mémoire lors du défilement, elle est causée par les alloc s dans cellForRowAtIndexPath qui ne sont pas équilibrés soit par un release ou un autorelease.

Ce:

Group *groupForRow = [[[Group alloc] init] autorelease]; 
Person *personForRow = [[[Person alloc] init] autorelease]; 

devrait corriger la plupart de vos fuites. Parcourir autour de SO pour plus d'informations.