ios - 更改未在 Interface Builder 中创建的 UIButton 的文本

Question

这个问题似乎已经得到了很多答案，但发布的解决方案都不适合我。所以我想我应该尝试一下。我有一个 bool 值 posNeg ，每次它的值发生变化时，三个按钮的标题应该改变，但它们没有改变。

- (void) posNegButtonPressed{
    if (posNeg) {
        posNeg = NO;
        [oneButton setTitle:@"One" forState:UIControlStateNormal];
        [xButton setTitle:@"X" forState:UIControlStateNormal];
        [x2Button setTitle:@"X2" forState:UIControlStateNormal];
        NSLog(@"Was True");
    }
    else{
        posNeg = YES;
        [oneButton setTitle:@"-One" forState:UIControlStateNormal];
        [xButton setTitle:@"-X" forState:UIControlStateNormal];
        [x2Button setTitle:@"-X2" forState:UIControlStateNormal];
        NSLog(@"Was False");
    }
}

正在调用 NSLog，因此我不断收到“Was True”和“Was False”的交替序列，但每个按钮的标题从未更新。

附加信息:

按钮初始化如下

头文件

@interface ...{ 
    UIButton* oneButton;
    UIButton* xButton;
    UIButton* x2Button; 
} 
@end

实现文件

@implementation ...

- (id)initWithFrame:(CGRect)frame{
    self = [super initWithFrame:frame];
    if (self) {
        [self setUpButton : oneButton : UIButtonTypeRoundedRect : @"One" :UIControlStateNormal : @"Helvetica-Bold" : 20
                      : width - width/4 + 2 * initialWidth : height/3 + 6 * (buttonHeight + spaceBetweenButtons)
                      : width/4 - 2 * initialWidth : buttonHeight : @selector(oneButtonPressed) : UIControlEventTouchUpInside];

        [self setUpButton : xButton : UIButtonTypeRoundedRect : @"X" :UIControlStateNormal : @"Helvetica-Bold" : 20
                      : width - width/4 + 2 * initialWidth : height/3 + 7 * (buttonHeight + spaceBetweenButtons)
                      : width/4 - 2 * initialWidth : buttonHeight : @selector(xButtonPressed) : UIControlEventTouchUpInside];

        [self setUpButton : x2Button : UIButtonTypeRoundedRect : @"X\u00B2" :UIControlStateNormal : @"Helvetica-Bold" : 20
                      : width - width/4 + 2 * initialWidth : height/3 + 8 * (buttonHeight + spaceBetweenButtons)
                      : width/4 - 2 * initialWidth : buttonHeight : @selector(x2ButtonPressed) : UIControlEventTouchUpInside];
}

- (void) setUpButton: (UIButton *) button : (UIButtonType *) buttonType : (NSString *) title : (UIControlState *) controlState : (NSString *) font : (int) size : (double) xPos (double) yPos : (double) width : (double) height : (SEL) selectorMethod :(UIControlEvents *) controlEvent
{
    button = [UIButton buttonWithType:buttonType];
    button.frame = CGRectMake(xPos, yPos, width, height);
    [button setTitle:title controlState  ];
    [button addTarget:self action: selectorMethod forControlEvents:controlEvent];
    [self addSubview:button];
    button.titleLabel.font = [UIFont fontWithName:font size:size];
}

@end

我尝试了[mybutton setNeedsDisplay]，但也不起作用

有什么想法吗？我的按钮没有正确初始化吗？

编辑1:根据要求将NSLog(@"%@ %@ %@", oneButton, xButton, x2Button);添加到initWithFrame中的最后一行并得到(空)(空)(空)。有谁知道为什么他们是空的？

Answer 1

如果您使用 XIB，请为按钮设置 IBOutlet，下面的代码对我有用

- (IBAction)sliderButtonAction:(UIButton *)sender {

    [self.suggestedTableView reloadData];
    if ([sender.titleLabel.text isEqualToString:@"<<"]) {
        [sender setTitle:@">>" forState:UIControlStateNormal];
    }
    else {
        [sender setTitle: @"<<" forState: UIControlStateNormal];

    }
}