setEditing:animated:是否缺少动画？

Question

我在编程iOS时遇到了一个问题:当我试图为我的tableView定制编辑按钮时，我就是不能让它有动画效果。下面是我初始化tableview的过程：

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

    myTableView = [[UITableView alloc] initWithFrame:[[UIScreen mainScreen] applicationFrame] style:UITableViewStylePlain]; 
    myTableView.delegate = self; 
    myTableView.dataSource = self; 

    myTableView.autoresizesSubviews = YES; 

    .......

    self.view = myTableView; 

    UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemBookmarks target:self action:@selector(setEditing:animated:)];     
    self.navigationItem.rightBarButtonItem = addButton; 
    [addButton release]; 
} 

但是，当我使用self.editButtonItem而不是我的addButton时，编辑模式是动画的。这是我的setEditing:animated: method。我可以让我的表视图进入编辑模式，插入按钮立即出现在左边。我尝试过[myTableView reloadRowsAtIndexPaths:[myTableView indexPathsForVisibleRows] withRowAnimation:UITableViewRowAnimationAutomatic];，但它在iOS 4.3上不起作用。

- (void)setEditing:(BOOL)editing animated:(BOOL)animated{ 

if(self.editing){ 
    [super setEditing:NO animated:YES]; 
    [myTableView reloadRowsAtIndexPaths:[myTableView indexPathsForVisibleRows] withRowAnimation:UITableViewRowAnimationAutomatic]; 
    [myTableView reloadData]; 
    self.navigationItem.title = [selectedCellItem valueForKey:@"name"]; 
    UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemBookmarks target:self action:@selector(setEditing:animated:)];  
    self.navigationItem.rightBarButtonItem = addButton; 
    [self.navigationItem.rightBarButtonItem setStyle:UIBarButtonItemStylePlain]; 
    [addButton release]; 
} 
else { 
    [super setEditing:YES animated:YES]; 
    [myTableView reloadRowsAtIndexPaths:[myTableView indexPathsForVisibleRows] withRowAnimation:UITableViewRowAnimationAutomatic]; 
    self.navigationItem.title = @"Add to Favourites"; 
    UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(setEditing:animated:)];     
    self.navigationItem.rightBarButtonItem = doneButton; 
    [self.navigationItem.rightBarButtonItem setStyle:UIBarButtonItemStyleDone]; 
    [doneButton release]; 
    [myTableView reloadData]; 
} 

} 

Answer 1

我不认为你赋值的选择器能够发送两个参数：

@selector(setEditing:animated:)

按钮操作通常不发送参数，或者将其本身作为参数发送(通常为(id)sender)。因此，您所做的可能会被解释为发送NO作为第二个参数(所以是animated = NO)。

您应该添加一个新方法，如下所示：

-(void)toggleEditing
{
    [self setEditing:!self.isEditing animated:YES];
}

并设置按钮上的操作：

@selector(toggleEditing)

编辑

好的，下面是一些更详细的代码。

对于初学者来说，您的初始代码示例应该是viewDidLoad而不是viewWillAppear。它应该看起来像这样：

- (void)viewDidLoad 
{ 
    [super viewDidLoad];

    .... code where you set up the table view...

    UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemBookmarks target:self action:@selector(toggleEditing)];     
    self.navigationItem.rightBarButtonItem = addButton; 
    [addButton release]; 
} 

您的setEditing方法应该如下所示：

- (void)setEditing:(BOOL)editing animated:(BOOL)animated
{
    [super setEditing:editing animated:animated];
    if (editing)
    {
        // We are changing to edit mode
        UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(toggleEditing)];     
        self.navigationItem.rightBarButtonItem = doneButton; 
        [self.navigationItem.rightBarButtonItem setStyle:UIBarButtonItemStyleDone]; 
        [doneButton release];
        self.navigationItem.title = @"Add to Favourites";
    }
    else
    {
        // We are changing out of edit mode
        self.navigationItem.title = [selectedCellItem valueForKey:@"name"]; 
        UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemBookmarks target:self action:@selector(toggleEditing)];  
        self.navigationItem.rightBarButtonItem = addButton; 
        [self.navigationItem.rightBarButtonItem setStyle:UIBarButtonItemStylePlain]; 
        [addButton release];
        self.navigationItem.title = [selectedCellItem valueForKey:@"name"];
    } 
}