objective-c - 问题重新分配分配的对象

Question

崩溃发生在 [searchDict 版本]。如果我切换两个最新行的顺序，它仍然会在最新行上崩溃（现在 [searchArray 版本]）。我对Objective C很陌生，我想我没有正确分配/释放...帮助？:)

NSMutableDictionary *searchDict = [[NSMutableDictionary alloc] init];
NSMutableArray *searchArray = [[NSMutableArray alloc] init];

for(int i = 0; i < 2; i++) { // Run two times ("Favorites" and "All")
    searchDict = [listOfItems objectAtIndex:i];
    searchArray = [searchDict objectForKey:@"Entries"];

    for (NSString *sTemp in searchArray) {
        NSRange titleResultsRange = [sTemp rangeOfString:searchText options:NSCaseInsensitiveSearch];
        if (titleResultsRange.length > 0)
            [listOfItemsDynamic addObject:sTemp];
    }
}

[searchArray release];
[searchDict release];

Answer 1

您分配空间并将其分配给变量：

NSMutableDictionary *searchDict = [[NSMutableDictionary alloc] init];
NSMutableArray *searchArray = [[NSMutableArray alloc] init];

但是随后您将非本地分配的数据分配给它们：

searchDict = [listOfItems objectAtIndex:i];
searchArray = [searchDict objectForKey:@"Entries"];

所以基本上，你不需要分配和释放。而是做这样的事情：

NSMutableDictionary *searchDict; // Just declartion, no allocation / init
NSMutableArray *searchArray;     // Just declartion, no allocation / init

for(int i = 0; i < 2; i++) { // Run two times ("Favorites" and "All")
    searchDict = [listOfItems objectAtIndex:i];
    searchArray = [searchDict objectForKey:@"Entries"];

    for (NSString *sTemp in searchArray) {
        NSRange titleResultsRange = [sTemp rangeOfString:searchText options:NSCaseInsensitiveSearch];
        if (titleResultsRange.length > 0)
            [listOfItemsDynamic addObject:sTemp];
    }
}

// No release needed here

如果你熟悉 C，它类似于：

char *pChar;
pChar = malloc(15); // allocate memory and assign to pChar
pChar = "Hello";    // assign new address to pChar
free(pChar); // Error here ;)