我正在使用以下代码填充UITableViewController
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = @"Cell";
NSString *selectedWord;
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier] autorelease];
}
ResultDetail *detail = [[[GameStore defaultStore] currentResultDetail] objectAtIndex:[indexPath row]];
if([[detail selectedWord] isEqualToString:@" "])
{
selectedWord = @" selected: n/a";
}
else{
selectedWord = [NSString stringWithFormat:@" selected: %@", [[detail selectedWord] substringFromIndex:4]];
}
[[cell textLabel] setText:[NSString stringWithFormat:@" %@ (score: %d/4)",[detail word],[detail score]]];
[[cell detailTextLabel] setText:selectedWord];
detail = nil;
[detail release];
selectedWord = nil;
[selectedWord release];
return cell;
}
鉴于之前未请求currentResultDetail的值,因此上述代码运行良好。
这是currentResultDetail的代码
-(NSArray *)currentResultDetail {
NSLog(@"predicate: resultid == %d", [[GameStore defaultStore] currentResultId]);
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"resultId == %d", [[GameStore defaultStore] currentResultId] ];
NSArray *filtered = [[[GameStore defaultStore] allResults] filteredArrayUsingPredicate:predicate]; // failed here but only if currentResultId has been requested before.
predicate = nil;
[predicate release];
return [[filtered objectAtIndex:0] resultDetails];
}
上面的代码在以下行中失败:
NSArray *filtered = [[[GameStore defaultStore] allResults] filteredArrayUsingPredicate:predicate];
因此,基本上,如果用户以该顺序为currentResultId 1、2、3、4、5、6、7请求currentResultDetail,它就可以正常工作。但是,如果他们请求1,2,3,4,5,1,它将崩溃。
关于为什么会发生这种情况的任何指示?
最佳答案
您的谓词将自动释放。不要手动释放它,否则当autoreleasepool试图释放它时会崩溃。
关于iphone - 使用NSPredicate过滤数组会在第二次尝试时导致exc_bad_access,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/9388559/