Windows Phone 7 Stock Pivot 控制速度慢？

Question

我有 Mango 的 Pivot 应用程序的未编辑版本，当我运行它时，控制速度非常慢，有没有办法加快速度？

我所说的慢是指，当我多次快速地将手指滑过屏幕时 - 就像我在 iPhone 上所做的那样，它真的很慢，当我将手指移开时，它仍然穿过窗户。

我还在真实设备 (HTC HD7) 上的其他应用程序（例如 IM+、Kik Messenger 等）上对此进行了测试...它运行良好。

XAML 代码：

<phone:PhoneApplicationPage
x:Class="PivotApp1.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
xmlns:controls="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
mc:Ignorable="d" d:DesignWidth="480" d:DesignHeight="768" 
d:DataContext="{d:DesignData SampleData/MainViewModelSampleData.xaml}"
FontFamily="{StaticResource PhoneFontFamilyNormal}"
FontSize="{StaticResource PhoneFontSizeNormal}"
Foreground="{StaticResource PhoneForegroundBrush}"
SupportedOrientations="Portrait"  Orientation="Portrait"
shell:SystemTray.IsVisible="True">

<!--LayoutRoot is the root grid where all page content is placed-->
<Grid x:Name="LayoutRoot" Background="Transparent">
    <!--Pivot Control-->
    <controls:Pivot Title="MY APPLICATION">
        <!--Pivot item one-->
        <controls:PivotItem Header="first">
            <!--Double line list with text wrapping-->
            <ListBox x:Name="FirstListBox" Margin="0,0,-12,0" ItemsSource="{Binding Items}">
                <ListBox.ItemTemplate>
                    <DataTemplate>
                      <StackPanel Margin="0,0,0,17" Width="432" Height="78">
                          <TextBlock Text="{Binding LineOne}" TextWrapping="Wrap" Style="{StaticResource PhoneTextExtraLargeStyle}"/>
                          <TextBlock Text="{Binding LineTwo}" TextWrapping="Wrap" Margin="12,-6,12,0" Style="{StaticResource PhoneTextSubtleStyle}"/>
                      </StackPanel>
                    </DataTemplate>
                </ListBox.ItemTemplate>
            </ListBox>
        </controls:PivotItem>

        <!--Pivot item two-->
        <controls:PivotItem Header="second"> 
            <!--Triple line list no text wrapping-->
                <ListBox x:Name="SecondListBox" Margin="0,0,-12,0" ItemsSource="{Binding Items}">
                    <ListBox.ItemTemplate>
                        <DataTemplate>
                            <StackPanel Margin="0,0,0,17">
                                <TextBlock Text="{Binding LineOne}" TextWrapping="NoWrap" Margin="12,0,0,0" Style="{StaticResource PhoneTextExtraLargeStyle}"/>
                                <TextBlock Text="{Binding LineThree}" TextWrapping="NoWrap" Margin="12,-6,0,0" Style="{StaticResource PhoneTextSubtleStyle}"/>
                            </StackPanel>
                        </DataTemplate>
                    </ListBox.ItemTemplate>
                </ListBox>
        </controls:PivotItem>
    </controls:Pivot>
</Grid>

<!--Sample code showing usage of ApplicationBar-->
<!--<phone:PhoneApplicationPage.ApplicationBar>
    <shell:ApplicationBar IsVisible="True" IsMenuEnabled="True">
        <shell:ApplicationBarIconButton IconUri="/Images/appbar_button1.png" Text="Button 1"/>
        <shell:ApplicationBarIconButton IconUri="/Images/appbar_button2.png" Text="Button 2"/>
        <shell:ApplicationBar.MenuItems>
            <shell:ApplicationBarMenuItem Text="MenuItem 1"/>
            <shell:ApplicationBarMenuItem Text="MenuItem 2"/>
        </shell:ApplicationBar.MenuItems>
    </shell:ApplicationBar>
</phone:PhoneApplicationPage.ApplicationBar>-->

C# MainPage.xaml.cs 代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using Microsoft.Phone.Controls;

namespace PivotApp1
{
    public partial class MainPage : PhoneApplicationPage
    {
        // Constructor
        public MainPage()
        {
            InitializeComponent();

            // Set the data context of the listbox control to the sample data
            DataContext = App.ViewModel;
            this.Loaded += new RoutedEventHandler(MainPage_Loaded);
        }

        // Load data for the ViewModel Items
        private void MainPage_Loaded(object sender, RoutedEventArgs e)
        {
            if (!App.ViewModel.IsDataLoaded)
            {
                App.ViewModel.LoadData();
            }
        }
    }
}

C# App.xaml.cs 代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Navigation;
using System.Windows.Shapes;
using Microsoft.Phone.Controls;
using Microsoft.Phone.Shell;

namespace PivotApp1
{
    public partial class App : Application
    {
        private static MainViewModel viewModel = null;

        /// <summary>
        /// A static ViewModel used by the views to bind against.
        /// </summary>
        /// <returns>The MainViewModel object.</returns>
        public static MainViewModel ViewModel
        {
            get
            {
                // Delay creation of the view model until necessary
                if (viewModel == null)
                    viewModel = new MainViewModel();

                return viewModel;
            }
        }

        /// <summary>
        /// Provides easy access to the root frame of the Phone Application.
        /// </summary>
        /// <returns>The root frame of the Phone Application.</returns>
        public PhoneApplicationFrame RootFrame { get; private set; }

        /// <summary>
        /// Constructor for the Application object.
        /// </summary>
        public App()
        {
            // Global handler for uncaught exceptions. 
            UnhandledException += Application_UnhandledException;

            // Standard Silverlight initialization
            InitializeComponent();

            // Phone-specific initialization
            InitializePhoneApplication();

            // Show graphics profiling information while debugging.
            if (System.Diagnostics.Debugger.IsAttached)
            {
                // Display the current frame rate counters
                Application.Current.Host.Settings.EnableFrameRateCounter = true;

                // Show the areas of the app that are being redrawn in each frame.
                //Application.Current.Host.Settings.EnableRedrawRegions = true;

                // Enable non-production analysis visualization mode, 
                // which shows areas of a page that are handed off to GPU with a colored overlay.
                //Application.Current.Host.Settings.EnableCacheVisualization = true;

                // Disable the application idle detection by setting the UserIdleDetectionMode property of the
                // application's PhoneApplicationService object to Disabled.
                // Caution:- Use this under debug mode only. Application that disables user idle detection will continue to run
                // and consume battery power when the user is not using the phone.
                PhoneApplicationService.Current.UserIdleDetectionMode = IdleDetectionMode.Disabled;
            }
        }

        // Code to execute when the application is launching (eg, from Start)
        // This code will not execute when the application is reactivated
        private void Application_Launching(object sender, LaunchingEventArgs e)
        {
        }

        // Code to execute when the application is activated (brought to foreground)
        // This code will not execute when the application is first launched
        private void Application_Activated(object sender, ActivatedEventArgs e)
        {
            // Ensure that application state is restored appropriately
            if (!App.ViewModel.IsDataLoaded)
            {
                App.ViewModel.LoadData();
            }
        }

        // Code to execute when the application is deactivated (sent to background)
        // This code will not execute when the application is closing
        private void Application_Deactivated(object sender, DeactivatedEventArgs e)
        {
        }

        // Code to execute when the application is closing (eg, user hit Back)
        // This code will not execute when the application is deactivated
        private void Application_Closing(object sender, ClosingEventArgs e)
        {
            // Ensure that required application state is persisted here.
        }

        // Code to execute if a navigation fails
        private void RootFrame_NavigationFailed(object sender, NavigationFailedEventArgs e)
        {
            if (System.Diagnostics.Debugger.IsAttached)
            {
                // A navigation has failed; break into the debugger
                System.Diagnostics.Debugger.Break();
            }
        }

        // Code to execute on Unhandled Exceptions
        private void Application_UnhandledException(object sender, ApplicationUnhandledExceptionEventArgs e)
        {
            if (System.Diagnostics.Debugger.IsAttached)
            {
                // An unhandled exception has occurred; break into the debugger
                System.Diagnostics.Debugger.Break();
            }
        }

        #region Phone application initialization

        // Avoid double-initialization
        private bool phoneApplicationInitialized = false;

        // Do not add any additional code to this method
        private void InitializePhoneApplication()
        {
            if (phoneApplicationInitialized)
                return;

            // Create the frame but don't set it as RootVisual yet; this allows the splash
            // screen to remain active until the application is ready to render.
            RootFrame = new PhoneApplicationFrame();
            RootFrame.Navigated += CompleteInitializePhoneApplication;

            // Handle navigation failures
            RootFrame.NavigationFailed += RootFrame_NavigationFailed;

            // Ensure we don't initialize again
            phoneApplicationInitialized = true;
        }

        // Do not add any additional code to this method
        private void CompleteInitializePhoneApplication(object sender, NavigationEventArgs e)
        {
            // Set the root visual to allow the application to render
            if (RootVisual != RootFrame)
                RootVisual = RootFrame;

            // Remove this handler since it is no longer needed
            RootFrame.Navigated -= CompleteInitializePhoneApplication;
        }

        #endregion
    }
}

C# MainViewModel.cs

using System;
using System.ComponentModel;
using System.Collections.Generic;
using System.Diagnostics;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
using System.Collections.ObjectModel;


namespace PivotApp1
{
    public class MainViewModel : INotifyPropertyChanged
    {
        public MainViewModel()
        {
            this.Items = new ObservableCollection<ItemViewModel>();
        }

        /// <summary>
        /// A collection for ItemViewModel objects.
        /// </summary>
        public ObservableCollection<ItemViewModel> Items { get; private set; }

        private string _sampleProperty = "Sample Runtime Property Value";
        /// <summary>
        /// Sample ViewModel property; this property is used in the view to display its value using a Binding
        /// </summary>
        /// <returns></returns>
        public string SampleProperty
        {
            get
            {
                return _sampleProperty;
            }
            set
            {
                if (value != _sampleProperty)
                {
                    _sampleProperty = value;
                    NotifyPropertyChanged("SampleProperty");
                }
            }
        }

        public bool IsDataLoaded
        {
            get;
            private set;
        }

        /// <summary>
        /// Creates and adds a few ItemViewModel objects into the Items collection.
        /// </summary>
        public void LoadData()
        {
            // Sample data; replace with real data
            this.Items.Add(new ItemViewModel() { LineOne = "runtime one", LineTwo = "Maecenas praesent accumsan bibendum", LineThree = "Facilisi faucibus habitant inceptos interdum lobortis nascetur pharetra placerat pulvinar sagittis senectus sociosqu" });
            this.Items.Add(new ItemViewModel() { LineOne = "runtime two", LineTwo = "Dictumst eleifend facilisi faucibus", LineThree = "Suscipit torquent ultrices vehicula volutpat maecenas praesent accumsan bibendum dictumst eleifend facilisi faucibus" });
            this.Items.Add(new ItemViewModel() { LineOne = "runtime three", LineTwo = "Habitant inceptos interdum lobortis", LineThree = "Habitant inceptos interdum lobortis nascetur pharetra placerat pulvinar sagittis senectus sociosqu suscipit torquent" });
            this.Items.Add(new ItemViewModel() { LineOne = "runtime four", LineTwo = "Nascetur pharetra placerat pulvinar", LineThree = "Ultrices vehicula volutpat maecenas praesent accumsan bibendum dictumst eleifend facilisi faucibus habitant inceptos" });
            this.Items.Add(new ItemViewModel() { LineOne = "runtime five", LineTwo = "Maecenas praesent accumsan bibendum", LineThree = "Maecenas praesent accumsan bibendum dictumst eleifend facilisi faucibus habitant inceptos interdum lobortis nascetur" });
            this.Items.Add(new ItemViewModel() { LineOne = "runtime six", LineTwo = "Dictumst eleifend facilisi faucibus", LineThree = "Pharetra placerat pulvinar sagittis senectus sociosqu suscipit torquent ultrices vehicula volutpat maecenas praesent" });
            this.Items.Add(new ItemViewModel() { LineOne = "runtime seven", LineTwo = "Habitant inceptos interdum lobortis", LineThree = "Accumsan bibendum dictumst eleifend facilisi faucibus habitant inceptos interdum lobortis nascetur pharetra placerat" });
            this.Items.Add(new ItemViewModel() { LineOne = "runtime eight", LineTwo = "Nascetur pharetra placerat pulvinar", LineThree = "Pulvinar sagittis senectus sociosqu suscipit torquent ultrices vehicula volutpat maecenas praesent accumsan bibendum" });
            this.Items.Add(new ItemViewModel() { LineOne = "runtime nine", LineTwo = "Maecenas praesent accumsan bibendum", LineThree = "Facilisi faucibus habitant inceptos interdum lobortis nascetur pharetra placerat pulvinar sagittis senectus sociosqu" });
            this.Items.Add(new ItemViewModel() { LineOne = "runtime ten", LineTwo = "Dictumst eleifend facilisi faucibus", LineThree = "Suscipit torquent ultrices vehicula volutpat maecenas praesent accumsan bibendum dictumst eleifend facilisi faucibus" });
            this.Items.Add(new ItemViewModel() { LineOne = "runtime eleven", LineTwo = "Habitant inceptos interdum lobortis", LineThree = "Habitant inceptos interdum lobortis nascetur pharetra placerat pulvinar sagittis senectus sociosqu suscipit torquent" });
            this.Items.Add(new ItemViewModel() { LineOne = "runtime twelve", LineTwo = "Nascetur pharetra placerat pulvinar", LineThree = "Ultrices vehicula volutpat maecenas praesent accumsan bibendum dictumst eleifend facilisi faucibus habitant inceptos" });
            this.Items.Add(new ItemViewModel() { LineOne = "runtime thirteen", LineTwo = "Maecenas praesent accumsan bibendum", LineThree = "Maecenas praesent accumsan bibendum dictumst eleifend facilisi faucibus habitant inceptos interdum lobortis nascetur" });
            this.Items.Add(new ItemViewModel() { LineOne = "runtime fourteen", LineTwo = "Dictumst eleifend facilisi faucibus", LineThree = "Pharetra placerat pulvinar sagittis senectus sociosqu suscipit torquent ultrices vehicula volutpat maecenas praesent" });
            this.Items.Add(new ItemViewModel() { LineOne = "runtime fifteen", LineTwo = "Habitant inceptos interdum lobortis", LineThree = "Accumsan bibendum dictumst eleifend facilisi faucibus habitant inceptos interdum lobortis nascetur pharetra placerat" });
            this.Items.Add(new ItemViewModel() { LineOne = "runtime sixteen", LineTwo = "Nascetur pharetra placerat pulvinar", LineThree = "Pulvinar sagittis senectus sociosqu suscipit torquent ultrices vehicula volutpat maecenas praesent accumsan bibendum" });

            this.IsDataLoaded = true;
        }

        public event PropertyChangedEventHandler PropertyChanged;
        private void NotifyPropertyChanged(String propertyName)
        {
            PropertyChangedEventHandler handler = PropertyChanged;
            if (null != handler)
            {
                handler(this, new PropertyChangedEventArgs(propertyName));
            }
        }
    }
}

C# ItemViewModel.cs

using System;
using System.ComponentModel;
using System.Diagnostics;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;

namespace PivotApp1
{
    public class ItemViewModel : INotifyPropertyChanged
    {
        private string _lineOne;
        /// <summary>
        /// Sample ViewModel property; this property is used in the view to display its value using a Binding.
        /// </summary>
        /// <returns></returns>
        public string LineOne
        {
            get
            {
                return _lineOne;
            }
            set
            {
                if (value != _lineOne)
                {
                    _lineOne = value;
                    NotifyPropertyChanged("LineOne");
                }
            }
        }

        private string _lineTwo;
        /// <summary>
        /// Sample ViewModel property; this property is used in the view to display its value using a Binding.
        /// </summary>
        /// <returns></returns>
        public string LineTwo
        {
            get
            {
                return _lineTwo;
            }
            set
            {
                if (value != _lineTwo)
                {
                    _lineTwo = value;
                    NotifyPropertyChanged("LineTwo");
                }
            }
        }

        private string _lineThree;
        /// <summary>
        /// Sample ViewModel property; this property is used in the view to display its value using a Binding.
        /// </summary>
        /// <returns></returns>
        public string LineThree
        {
            get
            {
                return _lineThree;
            }
            set
            {
                if (value != _lineThree)
                {
                    _lineThree = value;
                    NotifyPropertyChanged("LineThree");
                }
            }
        }

        public event PropertyChangedEventHandler PropertyChanged;
        private void NotifyPropertyChanged(String propertyName)
        {
            PropertyChangedEventHandler handler = PropertyChanged;
            if (null != handler)
            {
                handler(this, new PropertyChangedEventArgs(propertyName));
            }
        }
    }
}

我正在运行几天前在 Microsoft 网站上发布的 WP 7.1 版本。

我不知道如何让应用程序加速，因为当我用手指划过它时，它比 iOS 滞后，而且不流畅，我把它拿下来几秒钟，它仍然试图赶上我所在的位置。

Answer 1

我认为您正在使用库存 Pivot 应用程序模板作为 Windows Phone SDK 7.1（Mango RTM 版本）的一部分，在这种情况下应该没有问题。

我刚刚在本地启动了模板并运行它，没有出现任何问题，因此如果可以的话，您可能想尝试一个新的副本。

在模板中没有 C# 可言，它只是加载两个列表以显示到视图中的两个列表框，没有什么特别的。当然，这不是最有效的方法，因为在填充两个列表之前显示不会渲染，最好使用某种级别的虚拟化并为每个视图单独加载两个列表。

我接受 Claus 关于在堆栈面板上使用网格的评论，但在大多数情况下，除非您在堆栈面板中使用堆栈面板，否则没有真正的问题，并且堆栈面板如何处理布局的好处可能是一个巨大的好处。

如果您对默认模板做了任何其他操作，请告诉我，我将尽可能扩展

Answer 2

您的问题与您的 XAML 无关。它与后台运行的C#代码有关。

问题是您给 UI 线程添加了沉重的负载，因此也在 UI 线程上运行的枢轴之间的导航严重滞后。

我们需要查看相关的 C# 代码（代码隐藏/视图模型等）以提供更详细的建议。

至于您的 XAML，如果可能的话，一个好的建议是在您的 DataTemplate 中使用 Grid 而不是 StackPanel，因为它可以改进虚拟化列表元素。