UITableView與自定義UITableViewCell無法正常顯示

Question

我有一個自定義UITableViewCell（實際上我已經爲不同的表格分幾次），偶爾桌子會開始「降級」並慢慢崩潰。這是不可能重現崩潰，並將其與以下調用堆棧崩潰：

特定應用信息：
訂購遠程未能及時恢復

經過的總CPU時間（秒）：0.240（用戶0.040，系統0.200），12％的CPU
經過的應用CPU時間（秒）：0.000，0％CPU

Thread 0: 
0 libSystem.B.dylib    0x310932b8 semaphore_wait_trap + 8 
1 libSystem.B.dylib    0x310c0b46 semaphore_wait + 2 
2 libSystem.B.dylib    0x3116a7c4 _dispatch_semaphore_wait_slow + 296 
3 libSystem.B.dylib    0x31169cb4 _dispatch_barrier_sync_f_slow + 128 
4 CoreFoundation     0x3042bb70 __CFMachPortPerform + 92 
5 CoreFoundation     0x304236f8 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 20 
6 CoreFoundation     0x304236bc __CFRunLoopDoSource1 + 160 
7 CoreFoundation     0x30415f76 __CFRunLoopRun + 514 
8 CoreFoundation     0x30415c80 CFRunLoopRunSpecific + 224 
9 CoreFoundation     0x30415b88 CFRunLoopRunInMode + 52 
10 GraphicsServices    0x31eec4a4 GSEventRunModal + 108 
11 GraphicsServices    0x31eec550 GSEventRun + 56 
12 UIKit       0x313cf322 -[UIApplication _run] + 406 
13 UIKit       0x313cce8c UIApplicationMain + 664 
14 Order Remote     0x00002a02 0x1000 + 6658 
15 Order Remote     0x000029cc 0x1000 + 6604 

這裏是個什麼樣子，當它快要崩潰一樣......

http://img819.imageshack.us/i/uitableviewmissingdata2.jpg/

http://img220.imageshack.us/i/uitableviewmissingdata1.jpg/

我已經通過我的所有的內存管理代碼並啓用殭屍和檢查我如何繼承的單元格，我看不到的地方，我錯了。請幫幫我。

...

這裏是一些代碼

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath 
{ 
    MenuItemCell *cell = (MenuItemCell *)[tableView dequeueReusableCellWithIdentifier:@"MenuItemCell"]; 
    if (cell == nil) 
    { 
     cell = [[[MenuItemCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:@"MenuItemCell"] autorelease]; 
     DLog(@"MenuViewController::cellForRowAtIndexPath: allocating memory for a MenuItemCell"); 
    } 
    else 
    { 
     DLog(@"MenuViewController::cellForRowAtIndexPath: dequeuing an existing MenuItemCell for reuse"); 
    } 

    cell.accessoryType = UITableViewCellAccessoryNone; 

    // only display the item modifiers view if the item has one or more modifiers 
    if([[selectedCategory getModifiers] count] > 0) 
    { 
     cell.accessoryType = UITableViewCellAccessoryDetailDisclosureButton; 
    } 

    // Configure the cell. 
    cell.textLabel.text = [[items objectAtIndex:indexPath.row] name]; 

    // build a mutable string from the modifiers and set the text to the result in the detail label 
    NSMutableString* modifiers = [[NSMutableString alloc] initWithString:@""]; 
    Item* i = [items objectAtIndex:indexPath.row]; 

    for(ItemModifier* modifier_iterator in [i modifiers]) 
    { 
     [modifiers appendString: [modifier_iterator name]]; 
     [modifiers appendString: @" "]; 
    } 

    cell.detailTextLabel.text = modifiers; 

    [modifiers release]; 
    modifiers = nil; 

    [cell setItem: i]; 

    return cell; 
} 

@interface MenuItemCell：UITableViewCell的 { 的UILabel * ITEMCOUNT; }

- (void) setItem: (Item*) item; 
- (void) resetItemCount; 

@end 

@implementation MenuItemCell 

- (id) initWithStyle: (UITableViewCellStyle) style reuseIdentifier: (NSString*) reuseIdentifier 
{ 
    if((self = [super initWithStyle:style reuseIdentifier:reuseIdentifier])) 
    { 
     itemCount = [[UILabel alloc] initWithFrame:CGRectZero]; 
     [[self contentView] addSubview:itemCount]; 
    } 

    return self; 
} 

- (void) resetItemCount 
{ 
    [itemCount setText: @""]; 
    [self setNeedsDisplay]; 
} 

- (void) layoutSubviews 
{ 
    [super layoutSubviews]; 

    float inset = 10.0; 
    CGRect bounds = [[self contentView] bounds]; 
    float h = bounds.size.height; 
    float w = bounds.size.width; 

    CGRect accessoryViewBounds; 

    if(!self.accessoryView) 
    { 
     accessoryViewBounds = CGRectZero; 
    } 
    else 
    { 
     accessoryViewBounds = self.accessoryView.bounds; 
    } 

    CGRect textLabelBounds = self.textLabel.bounds; 

    CGRect innerFrame = CGRectMake(round(inset + w/2), textLabelBounds.origin.y, round(w/2 - accessoryViewBounds.size.width - inset * 3), h - 1); 

    if((innerFrame.size.height >= bounds.size.height) || (innerFrame.size.width >= bounds.size.width)) 
    { 
     [NSException raise:@"inner frame for MenuItemCell is larger than the contentView bounds" format:@"MenuItemCell (w: %d h: %d) contentView (w: %d h: %d)", innerFrame.size.width, innerFrame.size.height, bounds.size.width, bounds.size.height]; 
    } 

    // move the rectange to the right side of the cell 
    itemCount.textAlignment = UITextAlignmentRight; 
    itemCount.textColor = [UIColor redColor]; 
    itemCount.highlightedTextColor = [UIColor whiteColor]; 
    itemCount.font = [UIFont boldSystemFontOfSize:[UIFont labelFontSize]]; 

    [itemCount setFrame: innerFrame]; 
} 

- (void) setItem: (Item*) item 
{ 
    if([item count] > 0) 
    { 
     [itemCount setText: [NSString stringWithFormat: @"%d", [item count]]]; 
    } 
    else 
    { 
     [itemCount setText: @""]; 
    } 

    [self setNeedsDisplay]; 

    DLog(@"MenuItemCell::itemCount %@ %d", [item name], [item count]); 
} 

- (void) dealloc 
{ 
    [itemCount release]; 
    itemCount = nil; 

    [super dealloc]; 
} 

@end 

Answer 1

的問題是可能與不釋放在IBOutlet中定義viewDidUnload指針（我不能肯定，因爲行爲是如此的不穩定和非可再現）。我沒有意識到，他們保留，直到重新閱讀文檔。

我還將所有簡單訪問器都更改爲@properties，而不是定義自己的屬性以降低存儲管理技巧的風險。

... 

@interface MenuViewController : UIViewController <UITableViewDelegate, UITableViewDataSource> 
{ 
    IBOutlet UITableView* itemsTable; 
    NSMutableArray* items; 

    Category* selectedCategory; 
    Order* editingOrder; 
    NSIndexPath* selectedRow; 

    BOOL addItemToExistingOrder; 
} 

-(id)initWithCategory: (Category*)category; 
-(IBAction)addItem: (id)sender; 

@property (assign) Category* selectedCategory;  
@property (assign) NSMutableArray* items;  
@property (assign) Order* editingOrder;  
@property (assign) BOOL addItemToExistingOrder;  

@implementation 
- (void)viewDidUnload 
{  
    [super viewDidUnload]; 

    [selectedRow release]; 
    selectedRow = nil; 

    [itemsTable release]; 
    itemsTable = nil; 
}