现在大多app 都会有navgationbar 滑动效果,可能是因为炫酷、装逼吧!小菜鸟表示不懂!水平有限,和大家分享一下!送代码几行聊表心意!!!!
- (void)viewDidLoad {
[super viewDidLoad];
// self.navigationController.navigationBar.backgroundColor = [UIColor blueColor];
self.navigationController.navigationBar.translucent = NO;
// self.automaticallyAdjustsScrollViewInsets = NO;
self.title = @"我的颜色再变吗";
self.scollView.delegate = self;
self.scollView.contentSize = CGSizeMake(self.view.frame.size.width, self.view.frame.size.height * 3);
self.scollView.backgroundColor = [UIColor cyanColor];
}
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
//
UIColor *color = [UIColor blueColor];
CGFloat offsetY = scrollView.contentOffset.y;
if (offsetY > 64) {
CGFloat alpha = MIN (1,(offsetY - 20)/1000);
self.navigationController.navigationBar.backgroundColor = [color colorWithAlphaComponent:alpha];
} else {
self.navigationController.navigationBar.backgroundColor = [color colorWithAlphaComponent:0];
}
}
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