滚动uiwebview时隐藏并显示导航栏

user2966615 发表于 Dev

用户名

我需要帮助，我正在尝试构建一个应用程序，其中有一个viewcontroller带有auiwebview和一个navbar带有2个按钮的应用程序。我想做的是，当用户滚动uiwebview导航栏时，它会自动像滑动起来一样隐藏起来。但不能正常工作，我希望它能工作。让我在这里发布代码。在viewdidload我把这个。

[webPage.scrollView setDelegate:self];

然后我有这种方法

- (void) scrollViewDidScroll:(UIScrollView *)scrollView {
    if(scrollView.contentOffset.y == 0) {
        //show
        NSLog(@"Show");
        [self.navigationController setNavigationBarHidden:NO animated:YES];
    } else {
        NSLog(@"Hide");
        [self.navigationController setNavigationBarHidden:YES animated:YES];
        //hide
    }
}

它NSLog正确，但是没有别的navbar仍然停留。:(

iOS开发

您可以尝试以下方法：

1.声明导航栏，一个带有导航栏高度和2个BOOL变量的常量：

UINavigationBar *navBar;

static const CGFloat kNavBarHeight = 60.0f;

BOOL webViewScrollIsDragging;
BOOL webViewScrollIsDecelerating;

2.在viewDidLoad中编写以下内容：

 [webView.scrollView setContentInset:UIEdgeInsetsMake(kNavBarHeight, 0, 0, 0)];
 [webView.scrollView setScrollIndicatorInsets:UIEdgeInsetsMake(kNavBarHeight, 0, 0, 0)];
 [webView.scrollView setContentOffset:CGPointMake(0, -kNavBarHeight) animated:NO];
 webView.scrollView.delegate = self;

然后初始化并将其UINavigationBar作为子视图添加到self.view原点（还请确保您UIWebView具有相同的原点，即（0,0））。

3.实现UIScrollViewDelegate方法（别忘了添加UIScrollViewDelegate协议）：

#pragma mark - UIScrollViewDelegate Methods
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
    if (scrollView == webview.scrollView)
    {
        if (scrollView.contentOffset.y == 1 && !webViewScrollIsDragging && !webViewScrollIsDecelerating)
        {
            [UIView animateWithDuration:0.3
                                  delay:0.0
                                options: UIViewAnimationCurveEaseOut
                             animations:^(void) {
                                 CGRect navBarFrame = CGRectMake(0,-scrollView.contentOffset.y-kNavBarHeight, self.view.bounds.size.width, kNavBarHeight);
                                 navBar.frame = navBarFrame;
                             }
                             completion:nil];
        }
        else
        {
            CGRect navBarFrame = CGRectMake(0,-scrollView.contentOffset.y-kNavBarHeight, self.view.bounds.size.width, kNavBarHeight);
            navBar.frame = navBarFrame;
        }

        if (scrollView.contentOffset.y < -kNavBarHeight)
        {
            [webview.scrollView setScrollIndicatorInsets:UIEdgeInsetsMake(fabsf(scrollView.contentOffset.y), 0, 0, 0)];
        }
    }
}

- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
{
    if (scrollView == webview.scrollView)
    {
        webViewScrollIsDragging = YES;
    }
}

- (void) scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate
{
    if (scrollView == webview.scrollView)
    {
        webViewScrollIsDragging = NO;
    }
}

- (void) scrollViewWillBeginDecelerating:(UIScrollView *)scrollView
{
    if (scrollView == webview.scrollView)
    {
        webViewScrollIsDecelerating = YES;
    }
}

- (void) scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
    if (scrollView == webview.scrollView)
    {
        webViewScrollIsDecelerating = NO;
    }
}