2

我正在使用 UISplitViewController，当加载 Master VC（UITableViewController）并按下表格单元格时，它会创建 Detail VC（带有两个 UIWebViews 的 UIViewController）：


@implementation MasterVC

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    UIViewController  *detailViewController = nil;
    DetailVC *newDetailViewController = [[DetailVC alloc] initWithNibName:@"DetailVC" bundle:nil];
    detailViewController = newDetailViewController;

    // Update the split view controller's view controllers array.
    NSArray *viewControllers = [[NSArray alloc] initWithObjects:self.navigationController, detailViewController, nil];
    splitViewController.viewControllers = viewControllers;
    [viewControllers release];

    [detailViewController release];
}

如果我模拟内存警告，将释放 DetailVC（调用了didReceiveMemoryWarning、viewDidUnload、dealloc），但我在 MasterVC 中释放 viewControllers 的行中收到“-[UIView _invalidateSubviewCache]: message sent to deallocated instance”错误，其中有意义，因为它尝试加载由于内存警告而释放的 detailViewController (DetailVC)。为什么它必须发布详细的vc，因为它的视图是正在显示的，我不完全理解。

现在，如果不是在 didSelectRowAtIndexPath 中释放 detailViewController，而是在 viewWillDisappear 中释放它，一切正常：


@implementation MasterVC

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    UIViewController  *detailViewController = nil;
    DetailVC *newDetailViewController = [[DetailVC alloc] initWithNibName:@"DetailVC" bundle:nil];
    detailViewController = newDetailViewController;

    // Update the split view controller's view controllers array.
    NSArray *viewControllers = [[NSArray alloc] initWithObjects:self.navigationController, detailViewController, nil];
    splitViewController.viewControllers = viewControllers;
    [viewControllers release];

    // Released in viewWillDissapear   
    //[detailViewController release];
}

- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];

    MyAppDelegate *delegate = [[UIApplication sharedApplication] delegate];
    // Retrieve the detail vc and release it-[UIView _invalidateSubviewCache]: message sent to deallocated instance
    [[delegate.splitViewController.viewControllers objectAtIndex:1] release];
}

对我来说，当主视图控制器消失时释放细节视图控制器（有些）有意义，但是，它仍然有点像黑客（加上静态分析器抱怨没有在“正确”中释放细节 vc地方）。还有其他更好的方法来解决这个问题吗？

4

0 回答 0