objective-c - Cocoa Touch 上不显示 UIButton 的 titleLabel.text

Question

我在运行时创建了一个新的 UIButton 并设置了它的 titleLabel 文本后，按钮的文本仍然没有显示。

我做错了什么？

-(IBAction) cloneMe: (id) sender{

    if (!currentY) {
        currentY = [sender frame].origin.y;
    }

    UIButton *clone = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    CGRect cloneFrame = [sender frame];
    cloneFrame.origin.y += currentY + cloneFrame.size.height + 30;
    clone.frame = cloneFrame;
    [clone titleLabel].text = @"I'm a clone";

    [[sender superview] addSubview:clone];

    currentY = cloneFrame.origin.y + cloneFrame.size.height;


}

Answer 1

你需要:

[clone setTitle:@"I'm a clone" forState:UIControlStateNormal];

查看 UIControl API 文档，了解 forState: 参数的其他有效值。