為button設(shè)置背景圖片，默認(rèn)會(huì)有點(diǎn)擊閃爍的效果，這個(gè)效果是通過button 的highlighted屬性來控制的，點(diǎn)擊button的時(shí)候highlighted為YES,松開后highlighted為NO.所以只要在點(diǎn)擊事件處理方法中將highlighted設(shè)置為NO就可以了

示例如下：

- (void)viewDidLoad {
    [super viewDidLoad];
    UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
    button.backgroundColor = [UIColor cyanColor];
    [button setTitle:@"+" forState:UIControlStateNormal];
    button.frame = CGRectMake(100, 64, 100, 30);
    [button setBackgroundImage:[UIImage imageNamed:@"btn_bg"] forState:UIControlStateNormal];
    [self.view addSubview:button];
    [button addTarget:self action:@selector(buttonTapped:) forControlEvents:UIControlEventTouchUpInside];
    //保證所有touch事件button的highlighted屬性為NO,即可去除高亮效果
    [button addTarget:self action:@selector(preventFlicker:) forControlEvents:UIControlEventAllTouchEvents];
}

- (void)buttonTapped:(UIButton *)button {
    NSLog(@"touch up inside");
}

- (void)preventFlicker:(UIButton *)button {
    button.highlighted = NO;
}