UITableView在viewDidLoad中获得初始化？

Question

我有一个VC，我正在初始化，并在其中是一个View。在View是UITableView,UIButton和UIImage。

我与按钮搞乱属性时，忽然，砰：

Assertion failure in -[UITableView _createPreparedCellForGlobalRow:withIndexPath:] 

进一步挖掘后，那是因为我的代码：

UINib *animCellNib = [UINib nibWithNibName:@"IoUISEAnimationDetailListingCell" bundle:nil]; 
[animationDetailsTableView registerNib:animCellNib forCellReuseIdentifier:@"AnimationDetailListingCell"]; 

没有得到执行。在我的viewDidLoad方法的顶部显示了进一步的挖掘，它跳转到初始化tableView。因此，从我的方法名称跟踪中，可以看到它以numberOfSectionsInTableView开头。虽然这只是发生了几行到我viewDidLoad

2011-10-12 15:43:42.113 io[5052:11903] <IoUISEAnimationDetailsViewController: 0x764c460> - initWithNibName:bundle: 
2011-10-12 15:43:42.116 io[5052:11903] <IoUISEAnimationDetailsViewController: 0x764c460> - viewDidLoad 
Current language: auto; currently objective-c 
2011-10-12 15:43:49.017 io[5052:11903] <IoUISEAnimationDetailsViewController: 0x764c460> - numberOfSectionsInTableView: 
2011-10-12 15:43:49.017 io[5052:11903] <IoUISEAnimationDetailsViewController: 0x764c460> - tableView:titleForHeaderInSection: 
2011-10-12 15:43:49.017 io[5052:11903] <IoUISEAnimationDetailsViewController: 0x764c460> - tableView:titleForFooterInSection: 
2011-10-12 15:43:49.017 io[5052:11903] <IoUISEAnimationDetailsViewController: 0x764c460> - tableView:numberOfRowsInSection: 
2011-10-12 15:43:49.017 io[5052:11903] <IoUISEAnimationDetailsViewController: 0x764c460> - tableView:cellForRowAtIndexPath: 
2011-10-12 15:43:49.017 io[5052:11903] *** Assertion failure in -[UITableView _createPreparedCellForGlobalRow:withIndexPath:], /SourceCache/UIKit_Sim/UIKit-1912.3/UITableView.m:6072 
2011-10-12 15:43:49.018 io[5052:11903] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'UITableView dataSource must return a cell from tableView:cellForRowAtIndexPath:' 

在viewDidLoad方法，一段时间后我设置saveButton.titleLabel.lineBreakMode和saveButton setBackgroundImage:newImage之前跳转到numberOfSectionsInTableView方法。

由于我的registerNib: forCellReuseIdentifier:代码位于按钮代码之后，因此单元笔尖未注册，因此导致我的dequeueReusableCellWithIdentifier返回零和崩溃。

为什么发生这种情况的任何提示？

这里是viewDidLoad的代码：

- (void)viewDidLoad { 
if (IoUIDebug & IoUIDebugSelectorNames) { 
    NSLog(@"%@ - %@", [self description], NSStringFromSelector(_cmd)); 
} 

[super viewDidLoad]; 



    // Create an Empty Tableview and steal its Background. 
    //set our background to it 
UITableView *tv = [[UITableView alloc] initWithFrame:self.view.frame style:UITableViewStyleGrouped]; 
UIView *backgroundView = tv.backgroundView; 
[self.view addSubview:backgroundView]; 
[tv release]; 
    // CGRect backgroundFrame = CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height); 
    //[backgroundView setFrame:backgroundFrame]; 
[self.view sendSubviewToBack:backgroundView]; 


saveButton.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter; 
saveButton.contentHorizontalAlignment = UIControlContentHorizontalAlignmentCenter; 
saveButton.titleLabel.textAlignment = UITextAlignmentCenter; 
saveButton.titleLabel.lineBreakMode = UILineBreakModeCharacterWrap; 

[saveButton setTitle:NSLocalizedStringFromTable(@"Save Animation Label",@"ScreenEditor",@"Save Animation Label") forState:UIControlStateNormal];  
[saveButton setTitleColor:[UIColor blackColor] forState:UIControlStateNormal]; 
saveButton.titleLabel.font = [UIFont boldSystemFontOfSize:17]; 

UIImage *newImage = [[UIImage imageNamed:@"BlueButtonSmall.png"] stretchableImageWithLeftCapWidth:12.0 topCapHeight:0.0]; 
[saveButton setBackgroundImage:newImage forState:UIControlStateNormal]; 

UIImage *newPressedImage = [[UIImage imageNamed:@"BlueButtonSmallPressed.png"] stretchableImageWithLeftCapWidth:12.0 topCapHeight:0.0]; 
[saveButton setBackgroundImage:newPressedImage forState:UIControlStateHighlighted]; 


    // in case the parent view draws with a custom color or gradient, use a transparent color 
saveButton.backgroundColor = [UIColor clearColor]; 


if (UIAppDelegate.ioMainViewController.currentDeployment.readOnlyMode == NO) {    // Only setup for the long press if the deployment is editable.. 
    instructionLabel.text = NSLocalizedStringFromTable(@"Animation Details Instructions", @"ScreenEditor", @""); 

} else { 
    instructionLabel.text = NSLocalizedStringFromTable(@"Locked Message", @"Configuration",@""); 
} 

IoCDElementAnimation * currentAnimation = UIAppDelegate.ioMainViewController.currentElementAnimation; 

if (currentAnimation) { 
    newAnimation = currentAnimation; 
    selectedSysCDAnimation = currentAnimation.sysAnimation; 
    selectedIoCDTag = currentAnimation.tag; 
    animationSaved = YES; 

} else { 
    selectedSysCDAnimation = nil; 
    selectedIoCDTag = nil; 
    animationSaved = NO; 
} 

UINib *animCellNib = [UINib nibWithNibName:@"IoUISEAnimationDetailListingCell" bundle:nil]; 

[animationDetailsTableView registerNib:animCellNib forCellReuseIdentifier:@"AnimationDetailListingCell"]; 

    // set our TableView Background to clear so we can see our new background 
[animationDetailsTableView setBackgroundView:nil]; 
[animationDetailsTableView setBackgroundColor:[UIColor clearColor]]; 

[self refreshContents:nil]; 

[self setupOrientation:[[UIApplication sharedApplication] statusBarOrientation]]; 
[self.view setNeedsLayout]; 
} 

在该方法中，dequeueReusableCellWithIdentifier:返回nil。由于viewDidLoad中的registerNib代码尚未运行，因此无法找到AnimationDetailListingCell标识符。看起来好像所有viewDidLoad都应该在发生初始化tableview之前运行，对吧？

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { 
if (IoUIDebug & IoUIDebugSelectorNames) { 
    NSLog(@"%@ - %@", [self description], NSStringFromSelector(_cmd)); 
} 
UITableViewCell *cell; 

cell = [animationDetailsTableView dequeueReusableCellWithIdentifier:@"AnimationDetailListingCell"]; 
// cell at this point in nil! 

[self configureCell:cell atIndexPath:indexPath]; 

return cell; 
} 

Answer 1

我有同样的错误。我认为这是因为调整某些按钮的属性意味着需要设置视图（显然是懒洋洋地创建），这意味着表需要准备好去，而且还没有，可能是因为它的数据源没有连接或者其他的东西。尝试将按钮调整移到稍后的viewDidLoad方法中;这对我有效。