button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
button.titleLabel.font            = [UIFont systemFontOfSize: 12];
button.titleLabel.lineBreakMode   = UILineBreakModeWordWrap;
button.titleLabel.numberOfLines   = 0;
button.titleLabel.shadowOffset    = CGSizeMake (1.0,0.0);
 
[button addTarget:self 
           action:@selector(myButtonClick) 
 forControlEvents:UIControlEventTouchDown];
 
button.frame = CGRectMake(0.0,100.0,317.0,100.0);
[button setTitle:string forState:UIControlStateNormal]; 
button.titleLabel.font            = [UIFont systemFontOfSize: 12];
button.titleLabel.text = @"ahoj";
 
NSMutableString *ObratString = [[NSMutableString alloc] initWithString:button.titleLabel.text];
 
[ObratString appendString:@"\n"];
[ObratString appendString:@"caw"];
[ObratString appendString:@"\n"];
[ObratString appendString:@"helllo"];
button.titleLabel.text = ObratString;
[ObratString release];
[self.view addSubview:button];

但最后我只看到第一行.
有什么办法让它工作吗？