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NavigationPage+CarouselPage:奇怪的滚动错误

carousel xamarin.forms xamarin

senseiwa · 技术社区 · 7 年前

我在玩 CarouselPage 现在是一个例子,因为我想转到其他页面,所以我用一个 NavigationPage 主要是:

    public App()
    {
        InitializeComponent();

        // Need navigation to have modal/nonmodal pages
        //MainPage = new MainPage();
        MainPage = new NavigationPage(new MainPage());
    }

XAML为iPhone X添加了安全区域,并删除了导航栏:

<?xml version="1.0" encoding="utf-8"?>
<CarouselPage xmlns="http://xamarin.com/schemas/2014/forms" xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml" xmlns:local="clr-namespace:Stoa" x:Class="Test.MainPage"
              xmlns:ios="clr-namespace:Xamarin.Forms.PlatformConfiguration.iOSSpecific;assembly=Xamarin.Forms.Core" 
              ios:Page.UseSafeArea="true" 
              NavigationPage.HasNavigationBar="False">            
    <ContentPage>
        <ContentPage.Padding>
            <OnPlatform x:TypeArguments="Thickness">
                <On Platform="iOS, Android" Value="0,40,0,0" />
            </OnPlatform>
        </ContentPage.Padding>
        <StackLayout>
            <Label Text="Green" FontSize="Medium" HorizontalOptions="Center" />
            <Button BackgroundColor="Green" WidthRequest="200" HeightRequest="200" HorizontalOptions="Center" VerticalOptions="CenterAndExpand" />
        </StackLayout>
    </ContentPage>
    <ContentPage>
        <ContentPage.Padding>
            <OnPlatform x:TypeArguments="Thickness">
                <On Platform="iOS, Android" Value="0,40,0,0" />
            </OnPlatform>
        </ContentPage.Padding>
        <StackLayout>
            <Label Text="Blue" FontSize="Medium" HorizontalOptions="Center" />
            <Button BackgroundColor="Blue" WidthRequest="200" HeightRequest="200" HorizontalOptions="Center" VerticalOptions="CenterAndExpand" />
        </StackLayout>
    </ContentPage>
</CarouselPage>

问题是现在用户 可以垂直滚动

有办法解决这个问题吗?

另一种方法是,如何从旋转木马视图中导航或“伪造”旋转木马?

1 回复 | 直到 7 年前

TouchBoarder 6 年前

这个“安全区域滚动偏移”可以通过设置UIScrollView的自定义iOS carouselpagerender来修复 ContentInstadJustmentBehavior到从未

更新时间: 上一个代码示例checked UIView.Subviews[0]是OnElementChanged中的UIScrollView,这可能引发System.IndexAutoFrangeException,导致SIGABRT崩溃。因此,我们在ViewDidLoad中检查它,如下所示: https://forums.xamarin.com/discussion/104385/ios-11-carousel-page-issues

[assembly: ExportRenderer(typeof(CarouselPage), typeof(CustomCarouselPageRenderer))]
namespace MyApp.iOS.Renderers
{
    public class CustomCarouselPageRenderer : CarouselPageRenderer
    {
        public override void ViewDidLoad()
        {
            base.ViewDidLoad();

            //Prevent vertical carousel scroll on iOS 11, 
            //we only want horizontal scroll in the carousel
            if (UIDevice.CurrentDevice.CheckSystemVersion(11, 0))
            {
             View.Subviews.OfType<UIScrollView>().Single().ContentInsetAdjustmentBehavior =
             UIScrollViewContentInsetAdjustmentBehavior.Never;
            }
        } 
    }
}

pjrki 7 年前

有一篇关于 https://github.com/alexrainman/CarouselView 当回购的所有者创建了自己的carousel并使用BindableProperties扩展它时,您只需设置方向即可。