Question

当用户到达（ScrollViewer）页面的末尾时，我试图打开App-Bar ... 因此，到达目的地时我需要一个指标......

我的Scrollviewer（也许是因为WP8）没有“ViewChanged”-event 喜欢张贴在其他问题
我认为这个解决方案对我的问题来说太过分了： http://blogs.msdn.com/b/slmperf/archive/2011/06/30/windows-phone-mango-change-listbox-how-to-detect-compression-end-of-scroll-states.aspx

我无法在此查看器中找到任何可以帮助我的事件......

       <ScrollViewer x:Name="SV_ScrollViewer"
                      Grid.Row="1" 
                      Margin="12,0,12,0"
                      ManipulationMode="Control"                       
                      AllowDrop="False">
            <Grid x:Name="ContentPanel">
                <StackPanel>
                    <Controls:Map                             
                        Height="730"
                        x:Name="M_MainMap"                                  
                        ZoomLevel="10" 
                        Loaded="Map_Loaded"/>
                    <phone:LongListSelector 
                        x:Name="LLS_FuelStations" 
                        Height="700">                        
                    </phone:LongListSelector>
                </StackPanel>                    
            </Grid>
        </ScrollViewer>

感谢您的帮助！

2-EDIT：LayoutUpdated-Event不适合再次关闭app-bar ...我最终得到一个Dispatcher-Timer来关闭并打开它。现在它工作正常（顺利）：

    // Constructor
    public MainPage()
    {
        InitializeComponent();           

        Dispatcher.BeginInvoke(() =>
        {
            //initialize timer
            if (timer == null)
            {
                int timerSpan = 500;
                timer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(timerSpan) };
                timer.Tick += (o, arg) => OffsetWatcher();
            }
        });
    }

关闭并打开app-bar：

private void OffsetWatcher()
        {
            if (SV_ScrollViewer.ScrollableHeight - SV_ScrollViewer.VerticalOffset > 100 )
            {
                if (ApplicationBar.IsVisible)
                {
                    ApplicationBar.IsVisible = false;
                    ApplicationBar.IsMenuEnabled = false;
                }
            }
            else
            {
                if (!ApplicationBar.IsVisible)
                {
                    BuildLocalizedApplicationBar();
                }   
            }
        }

Answer 1

使用布局更新这里我使用和调试的代码来获得滚动效果。您可能还需要保持已按下指针的轨道以及滚动查看器操作已完成事件。这是xaml在后面的代码中添加相应的事件处理程序。

 <ScrollViewer ManipulationCompleted="ScrollViewer_ManipulationCompleted" ManipulationMode="All">
        <StackPanel  LayoutUpdated="StackPanel_LayoutUpdated" PointerPressed="StackPanel_PointerPressed">
            <Grid Height="100" Width="100" Background="Red" ></Grid>
            <Grid Height="100" Width="100" Background="Green" ></Grid>
            <Grid Height="100" Width="100" Background="Blue" ></Grid>
            <Grid Height="100" Width="100" Background="Yellow" ></Grid>
            <Grid Height="100" Width="100" Background="Red" ></Grid>
            <Grid Height="100" Width="100" Background="Green" ></Grid>
            <Grid Height="100" Width="100" Background="Blue" ></Grid>
            <Grid Height="100" Width="100" Background="Yellow" ></Grid>
            <Grid Height="100" Width="100" Background="Red" ></Grid>
            <Grid Height="100" Width="100" Background="Green" ></Grid>
            <Grid Height="100" Width="100" Background="Blue" ></Grid>
            <Grid Height="100" Width="100" Background="Yellow" ></Grid>
            <Grid Height="100" Width="100" Background="Red" ></Grid>
            <Grid Height="100" Width="100" Background="Green" ></Grid>
            <Grid Height="100" Width="100" Background="Blue" ></Grid>
            <Grid Height="100" Width="100" Background="Yellow" ></Grid>
            <Grid Height="100" Width="100" Background="Red" ></Grid>
            <Grid Height="100" Width="100" Background="Green" ></Grid>
            <Grid Height="100" Width="100" Background="Blue" ></Grid>
            <Grid Height="100" Width="100" Background="Yellow" ></Grid>
            <Grid Height="100" Width="100" Background="Red" ></Grid>
            <Grid Height="100" Width="100" Background="Green" ></Grid>
            <Grid Height="100" Width="100" Background="Blue" ></Grid>
            <Grid Height="100" Width="100" Background="Yellow" ></Grid>
            <Grid Height="100" Width="100" Background="Red" ></Grid>
            <Grid Height="100" Width="100" Background="Green" ></Grid>
            <Grid Height="100" Width="100" Background="Blue" ></Grid>
            <Grid Height="100" Width="100" Background="Yellow" ></Grid>
            <Grid Height="100" Width="100" Background="Red" ></Grid>
            <Grid Height="100" Width="100" Background="Green" ></Grid>
            <Grid Height="100" Width="100" Background="Blue" ></Grid>
            <Grid Height="100" Width="100" Background="Yellow" ></Grid>
            <Grid Height="100" Width="100" Background="Red" ></Grid>
            <Grid Height="100" Width="100" Background="Green" ></Grid>
            <Grid Height="100" Width="100" Background="Blue" ></Grid>
            <Grid Height="100" Width="100" Background="Yellow" ></Grid>
        </StackPanel>
    </ScrollViewer>

这是

背后的代码

        public MainPage()
    {
        this.InitializeComponent();
    }

    /// <summary>
    /// Invoked when this page is about to be displayed in a Frame.
    /// </summary>
    /// <param name="e">Event data that describes how this page was reached.  The Parameter
    /// property is typically used to configure the page.</param>
    protected override void OnNavigatedTo(NavigationEventArgs e)
    {

    }


    private void ScrollViewer_ManipulationCompleted(object sender, ManipulationCompletedRoutedEventArgs e)
    {
        //scroll bar being dragged
    }

    private void StackPanel_LayoutUpdated(object sender, object e)
    {
        //if swipe gesture then check for vertical offset and carry on with the //calculations you have to do else do nothing
    }

    private void StackPanel_PointerPressed(object sender, PointerRoutedEventArgs e)
    {
        //swipe gesture being made
    }

如果有效，请告诉我

ScrollViewer到达底部的WindowsPhone8

1 个答案: