Ios4 获取UIButton的行数

Ios4 获取UIButton的行数,ios4,uibutton,ipad,multiline,Ios4,Uibutton,Ipad,Multiline,我有一个UIButton,我正在用一个字符串设置标题标签的文本,该字符串包含多个“\r\n”用于新行 //From previous logic, you have numLines = 3 NSString *string = [NSString stringWithString:@"this \r\n is a multi-line \r\n button"]; [button setNumberOfLines:numLines] [button.titleLabel setLineBr

我有一个UIButton,我正在用一个字符串设置标题标签的文本,该字符串包含多个“\r\n”用于新行

//From previous logic, you have numLines = 3

NSString *string = [NSString stringWithString:@"this \r\n is a multi-line \r\n button"];

[button setNumberOfLines:numLines]
[button.titleLabel setLineBreakMode:UILineBreakModeWordWrap];

NSLog(@"number of lines = %d", [button.titleLabel numberOfLines]);
但是输出的行数=0——我想是因为换行的行数是动态的

如何在换行后获得标题标签占用的实际行数