iphone - 内存泄漏问题

Question

有人可以告诉我为什么我在这段代码中有内存泄漏吗？

我在代码中添加了 Analyzer 中的注释。如果有人可以帮助我并解释为什么我会收到这两条评论，我将不胜感激？

- (void)viewDidDisappear:(BOOL)animated {

// Empty array to be sure it is empty
[playerArray removeAllObjects];

//============CLEAN OUT DOUBLE NAMES FROM ARRAY==============//
NSArray *sortedDummyArray = [[NSArray alloc] initWithArray:selectedPlayersArray];
    ////>>>>The line above is line 84<<<<<<<////

// Sort the array
sortedDummyArray = [sortedDummyArray sortedArrayUsingSelector:@selector(compare:)];

NSMutableArray *finalArray = [[NSMutableArray alloc]initWithArray:sortedDummyArray];
    ////>>>>>> Possible memory leak on line 84 <<<<<<<<//// 



int xx = [sortedDummyArray count];
int yy;
int counter = 0;
int rr = 0;

for (int oo = 0; oo < xx; oo++) {
    yy = [finalArray count];

    for (int zz = 0; zz < yy; zz++) {

        // If hit, clean out the double name
        if ([[sortedDummyArray objectAtIndex:oo] isEqualToString:[finalArray objectAtIndex:rr]]) {

            counter++;

            // Check if there is more than one of this name
            if (counter > 1) {
                [finalArray removeObjectAtIndex:rr];
                rr--;
                counter--;
            }
        }
        rr++;
    }
    counter = 0;
    rr = 0;
}

[sortedDummyArray retain];

// Save who is in the game

AccessQuestionsDB *shufflePlayersFunction = [AccessQuestionsDB new];
finalArray = [shufflePlayersFunction shufflePlayers: finalArray];
[shufflePlayersFunction release];

TempPlayersInTheGame *savePlayersInTheGame = [TempPlayersInTheGame new];
[savePlayersInTheGame saveSelectedPlayers:finalArray];
[savePlayersInTheGame release];

[finalArray release]; //>>>> see comment below
    ////>>>>>Incorrect decrement of the reference count of an object that is not owned at this point by the caller <<<<<<///// 

    [sortedDummyArray release];
[super viewDidDisappear:animated];

Answer 1

您的第一次泄漏是因为您调用:

[sortedDummyArray retain];

您已经调用了执行此操作的分配，但您最后只释放了一次(因此删除上面的行)您还重新分配了它，这是不正确的。

您的第二次泄漏 是因为您使用 alloc 设置了 finalArray，然后将其替换为函数的结果。您可以通过替换此行来解决此问题:

NSMutableArray *finalArray = [[NSMutableArray alloc]initWithArray:sortedDummyArray];

有了这个:

NSMutableArray *finalArray = [NSMutableArray arrayWithArray:sortedDummyArray];

然后删除这一行:

[finalArray release];

---

所以你的函数看起来像这样:

- (void)viewDidDisappear:(BOOL)animated {

    // Empty array to be sure it is empty
    [playerArray removeAllObjects];

    //============CLEAN OUT DOUBLE NAMES FROM ARRAY==============//   
    // Sort the array
    NSArray *sortedDummyArray = [selectedPlayersArray sortedArrayUsingSelector:@selector(compare:)];

    NSMutableArray *finalArray = [NSMutableArray arrayWithArray:sortedDummyArray];    

    int xx = [sortedDummyArray count];
    int yy;
    int counter = 0;
    int rr = 0;

    for (int oo = 0; oo < xx; oo++) {
        yy = [finalArray count];

        for (int zz = 0; zz < yy; zz++) {

            // If hit, clean out the double name
            if ([[sortedDummyArray objectAtIndex:oo] isEqualToString:[finalArray objectAtIndex:rr]]) {

               counter++;

               // Check if there is more than one of this name
               if (counter > 1) {
                   [finalArray removeObjectAtIndex:rr];
                   rr--;
                   counter--;
               }
            }
            rr++;
        }
        counter = 0;
        rr = 0;
    }

    // Save who is in the game

    AccessQuestionsDB *shufflePlayersFunction = [AccessQuestionsDB new];
    finalArray = [shufflePlayersFunction shufflePlayers: finalArray];
    [shufflePlayersFunction release];

    TempPlayersInTheGame *savePlayersInTheGame = [TempPlayersInTheGame new];
    [savePlayersInTheGame saveSelectedPlayers:finalArray];
    [savePlayersInTheGame release];

    [super viewDidDisappear:animated];
}

---

但所有这些都太过分了只是为了删除重复的条目，将您的数组转换为 NSSet(它始终是唯一的)然后将其转换回 NSArray 应该为您解决这个问题，所以你的函数应该是:

- (void)viewDidDisappear:(BOOL)animated {

    // Empty array to be sure it is empty
    [playerArray removeAllObjects];

    //============CLEAN OUT DOUBLE NAMES FROM ARRAY==============//   
    NSSet *uniquePlayers = [NSSet setWithArray:selectedPlayersArray];

    // Save who is in the game

    AccessQuestionsDB *shufflePlayersFunction = [AccessQuestionsDB new];
    NSArray *finalArray = [shufflePlayersFunction shufflePlayers: [uniquePlayers allObjects]];
    [shufflePlayersFunction release];

    TempPlayersInTheGame *savePlayersInTheGame = [TempPlayersInTheGame new];
    [savePlayersInTheGame saveSelectedPlayers:finalArray];
    [savePlayersInTheGame release];

    [super viewDidDisappear:animated];
}