如何更改Iphone sdk中UIButton标题的alpha值？

Question

我需要更改UIButton的alpha值，任何人都可以告诉我如何处理它。

而且按钮的代码，我写为：提前

UIView* buttonView = [[UIView alloc] initWithFrame:CGRectMake(10, 0, 100, 40)]; 
    buttonView.backgroundColor = [UIColor clearColor]; 

    backButton = [[UIButton alloc] initWithFrame:CGRectMake(5, 5, 100, 30)]; 
    [backButton setBackgroundImage:[UIImage imageNamed:@"backbutton_100.png"] forState:UIControlStateNormal]; 
    [backButton addTarget:self action:@selector(backAction:) forControlEvents:UIControlEventTouchUpInside]; 
    [backButton setTitle:@" All Customers" forState:UIControlStateNormal]; 
    backButton.titleLabel.font = [UIFont boldSystemFontOfSize:12];  
    [buttonView addSubview:backButton]; 

    UIBarButtonItem* leftButton = [[UIBarButtonItem alloc] initWithCustomView:buttonView]; 
    self.navigationItem.leftBarButtonItem = leftButton; 
    [leftButton release]; 

感谢。 Monish。

Answer 1

[backButton setTitleColor:[UIColor colorWithRed:0.3 green:0.6 blue:0.9 alpha:0.5] 
//        set 'alpha' to something less than 1. -----^^^ 
       forState:UIControlStateNormal];