UIButton -setTitle：forState：似乎不起作用

Question

我正在尝试动态更新UIButton的IBOutletCollection的标题。 我希望标题设置为

• 选中时字母'S'和
• 禁用和选择时文本“D | S”。

它没有用，所以我打印出了titleForState: s，看起来标题没有正确设置。 我是否正确使用setTitle: forState: ？

@property (strong, nonatomic) IBOutletCollection(UIButton) NSArray *buttons;
...
- (void)updateUI  // Calling this from IBAction
{
    for(UIButton *button in self.buttons) {
        [button setTitle:@"S" forState:UIControlStateSelected];
        [button setTitle:@"D|S" forState:UIControlStateSelected|UIControlStateDisabled];

        NSLog(@"%@ %@ %@ %@ %d %d",
              [button titleForState:UIControlStateSelected],
              [button titleForState:UIControlStateSelected],
              [button titleForState:UIControlStateNormal],
              [button titleForState:UIControlStateSelected|UIControlStateDisabled],
              button.selected,
              button.enabled);
    }
}

这是控制台输出：

2013-02-21 21:05:36.070 Buttons[37130:c07] D|S D|S   0 1
2013-02-21 21:05:36.072 Buttons[37130:c07] D|S D|S   0 1
2013-02-21 21:05:36.073 Buttons[37130:c07] D|S D|S   0 1
2013-02-21 21:05:36.073 Buttons[37130:c07] D|S D|S   0 1
2013-02-21 21:05:36.073 Buttons[37130:c07] D|S D|S   0 1
2013-02-21 21:05:36.074 Buttons[37130:c07] D|S D|S   0 1
2013-02-21 21:05:36.074 Buttons[37130:c07] D|S D|S   0 1
2013-02-21 21:05:36.074 Buttons[37130:c07] D|S D|S   0 1
2013-02-21 21:05:36.075 Buttons[37130:c07] D|S D|S   0 1
2013-02-21 21:05:36.075 Buttons[37130:c07] D|S D|S   0 1
2013-02-21 21:05:36.076 Buttons[37130:c07] D|S D|S   0 1
2013-02-21 21:05:36.076 Buttons[37130:c07] D|S D|S   0 1

Answer 1

它不起作用，因为IB设置了attributedTitle而不是title 。

试试这个：

NSAttributedString *attributedTitle = [self.myButton attributedTitleForState:UIControlStateNormal];
NSMutableAttributedString *mas = [[NSMutableAttributedString alloc] initWithAttributedString:attributedTitle];
[mas.mutableString setString:@"New Text"];

[self.myButton setAttributedTitle:mas forState:UIControlStateNormal];

或者，或者：

[self.myButton setAttributedTitle:nil forState:UIControlStateNormal];
[self.myButton setTitle:@"New Text" forState:UIControlStateNormal];

（第二个选项不会保留您的格式。）

Answer 2

在尝试了很多不同的事情之后，我得到它的唯一方法就是如下。 但这是一种C风格的逻辑，改变了选择和禁用UIButton控制状态的含义。 绝对是一个黑客:(

//        [cardButton setTitle:card.contents
//                    forState:UIControlStateSelected|UIControlStateDisabled];
if(cardButton.selected && !cardButton.enabled) {
    [cardButton setTitle:card.contents forState:UIControlStateNormal];
}

Answer 3

[button setTitle:@"S" forState:UIControlStateSelected];
        [button setTitle:@"D|S" forState:UIControlStateSelected|UIControlStateDisabled];

两种情况下用于UIControlStateSelected setTitle会使编译器混淆。 有可能立刻执行这两个条件。 尝试更改第二行中的代码。有一个快乐的编码