如何为UIButton的文本添加换行符？

Question

我想知道如何在UIButton上使用多行标签。

Answer 1

使用UIButton的titleLabel，特别是titleLabel.numberOfLines属性：

titleLabel
A view that displays the value of the currentTitle property for a button. (read-only)

@property(nonatomic,readonly,retain) UILabel *titleLabel
Discussion
Although this property is read-only, its own properties are read/write. Use these 
properties to configure the appearance of the button label. For example:

UIButton *button                  = [UIButton buttonWithType: UIButtonTypeRoundedRect];
button.titleLabel.font            = [UIFont systemFontOfSize: 12];
button.titleLabel.lineBreakMode   = UILineBreakModeTailTruncation;
button.titleLabel.shadowOffset    = CGSizeMake (1.0, 0.0);
The titleLabel property returns a value even if the button has not been displayed yet.
The value of the property is nil for system buttons.