UIActionSheetdelegate未获取子视图

Question

在我的iOS 8应用程序中，我使用了UIActionSheet。我试图在willPresentActionSheet委托方法中更改按钮标题的颜色，但它不能将按钮识别为它的子视图。

我是这样构建UIActionSheet的：

UIActionSheet *popup = [[UIActionSheet alloc] initWithTitle:@"Select an Option" delegate:self cancelButtonTitle:nil destructiveButtonTitle:nil otherButtonTitles: nil];
popup.tag = 2;
[popup addButtonWithTitle:@"Add Tag To Chat"];
[popup addButtonWithTitle:@"Remove Tag From Chat"];
[popup addButtonWithTitle:@"Terminate"];
[popup addButtonWithTitle:@"Cancel"];
[popup showInView:self.view];

委派是：

- (void)willPresentActionSheet:(UIActionSheet *)actionSheet
{
    NSLog(@"%d",[actionSheet.subviews count]);
    for (UIView *subview in actionSheet.subviews) {
        if ([subview isKindOfClass:[UIButton class]]) {
            UIButton *button = (UIButton *)subview;
            [button setTitleColor:[UIColor redColor] forState:UIControlStateNormal];
        }
    }
}

按钮正在显示，我可以单击并执行操作。但上面写着count = 0。为什么？

Answer 1

尝试这种方式，更改子视图的UIColor：

    UIActionSheet * action = [[UIActionSheet alloc]
                              initWithTitle:@"Title"
                              delegate:self
                              cancelButtonTitle:@"Cancel"
                              destructiveButtonTitle:nil
                              otherButtonTitles:@"",nil];
[[[action valueForKey:@"_buttons"] objectAtIndex:0] setTitleColor:[UIColor redColor] forState:UIControlStateNormal];

我试过了。它正在工作..。

Answer 2

尝试检查子视图数的委托方法：willPresentActionSheet似乎不合适。

在实际呈现操作表之前，将调用willPresentActionSheet。

如果你在didlPresentActionSheet，中检查子视图的数量，这会更合适。

希望这能帮上忙..