Question

我正在尝试编写ESurvey应用程序代码。我在每个页面都有一个单选按钮列表（共7页），当受访者点击上一页时，我想让单选按钮保存其检查状态。

using FYPPrototype1.Common;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices.WindowsRuntime;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Navigation;
using Windows.UI.Popups;

// The Basic Page item template is documented at http://go.microsoft.com/fwlink/?LinkId=234237

namespace FYPPrototype1
{
/// <summary>
/// A basic page that provides characteristics common to most applications.
/// </summary>
public sealed partial class SurveyPage2 : Page
{

    private NavigationHelper navigationHelper;
    private ObservableDictionary defaultViewModel = new ObservableDictionary();

    /// <summary>
    /// This can be changed to a strongly typed view model.
    /// </summary>
    public ObservableDictionary DefaultViewModel
    {
        get { return this.defaultViewModel; }
    }

    /// <summary>
    /// NavigationHelper is used on each page to aid in navigation and 
    /// process lifetime management
    /// </summary>
    public NavigationHelper NavigationHelper
    {
        get { return this.navigationHelper; }
    }


    public SurveyPage2()
    {
        this.InitializeComponent();
        this.navigationHelper = new NavigationHelper(this);
        this.navigationHelper.LoadState += navigationHelper_LoadState;
        this.navigationHelper.SaveState += navigationHelper_SaveState;
    }

    /// <summary>
    /// Populates the page with content passed during navigation. Any saved state is also
    /// provided when recreating a page from a prior session.
    /// </summary>
    /// <param name="sender">
    /// The source of the event; typically <see cref="NavigationHelper"/>
    /// </param>
    /// <param name="e">Event data that provides both the navigation parameter passed to
    /// <see cref="Frame.Navigate(Type, Object)"/> when this page was initially requested and
    /// a dictionary of state preserved by this page during an earlier
    /// session. The state will be null the first time a page is visited.</param>
    private void navigationHelper_LoadState(object sender, LoadStateEventArgs e)
    {
    }

    /// <summary>
    /// Preserves state associated with this page in case the application is suspended or the
    /// page is discarded from the navigation cache.  Values must conform to the serialization
    /// requirements of <see cref="SuspensionManager.SessionState"/>.
    /// </summary>
    /// <param name="sender">The source of the event; typically <see cref="NavigationHelper"/></param>
    /// <param name="e">Event data that provides an empty dictionary to be populated with
    /// serializable state.</param>
    private void navigationHelper_SaveState(object sender, SaveStateEventArgs e)
    {
    }

    #region NavigationHelper registration

    /// The methods provided in this section are simply used to allow
    /// NavigationHelper to respond to the page's navigation methods.
    /// 
    /// Page specific logic should be placed in event handlers for the  
    /// <see cref="GridCS.Common.NavigationHelper.LoadState"/>
    /// and <see cref="GridCS.Common.NavigationHelper.SaveState"/>.
    /// The navigation parameter is available in the LoadState method 
    /// in addition to page state preserved during an earlier session.

    protected override void OnNavigatedTo(NavigationEventArgs e)
    {
        navigationHelper.OnNavigatedTo(e);
    }

    protected override void OnNavigatedFrom(NavigationEventArgs e)
    {
        navigationHelper.OnNavigatedFrom(e);
    }

    #endregion

    private async void Button_S2_S3(object sender, RoutedEventArgs e)
    {
        if (RadioaAgree.IsChecked != true && RadioaNeutral.IsChecked != true && RadioaDisagree.IsChecked != true)
        {
            MessageDialog md = new MessageDialog("One or more options not selected. Please complete all options before proceeding!");
            await md.ShowAsync();
        }

        else if (RadiobAgree.IsChecked != true && RadiobNeutral.IsChecked != true && RadiobDisagree.IsChecked != true)
        {
            MessageDialog md = new MessageDialog("One or more options not selected. Please complete all options before proceeding!");
            await md.ShowAsync();
        }

        else if (RadiocAgree.IsChecked != true && RadiocNeutral.IsChecked != true && RadiocDisagree.IsChecked != true)
        {
            MessageDialog md = new MessageDialog("One or more options not selected. Please complete all options before proceeding!");
            await md.ShowAsync();
        }
        else if (RadiodAgree.IsChecked != true && RadiodNeutral.IsChecked != true && RadiodDisagree.IsChecked != true)
        {
            MessageDialog md = new MessageDialog("One or more options not selected. Please complete all options before proceeding!");
            await md.ShowAsync();
        }
        else
        {
            this.Frame.Navigate(typeof(SurveyPage3));
        }
    }
}
}

非常感谢所有那些帮助我的人！

Answer 1

您可以简单地存储局部变量，如布尔值，并在返回该页面时检查变量值并相应地更改radioButtons状态;）

//  these is the namespace of your class
namespace FYPPrototype1
{
    // these is the region of your class, where all functions and variables are stored
    public sealed partial class SurveyPage2 : Page
    {
        //  these are local variables
        private NavigationHelper navigationHelper;
        private ObservableDictionary defaultViewModel = new ObservableDictionary();

        // this is your class constructor
        public SurveyPage2()
        {
            InitializeComponent();

            this.navigationHelper = new NavigationHelper(this);
            this.navigationHelper.LoadState += navigationHelper_LoadState;
            this.navigationHelper.SaveState += navigationHelper_SaveState;
        }
.
.
.
    }
}

现在为了达到你所需要的，你必须做一个更复杂的事情，因为你可以看到你有一个加载和一个保存功能，即navigationHelper_LoadState和navigationHelper_SaveState，你可以存储和加载radioButtons的状态;）有关如何管理这些函数的更多信息，请参阅这些页面，它可以很好地解释它;）：http://mtaulty.com/CommunityServer/blogs/mike_taultys_blog/archive/2014/05/23/windows-phone-8-1-frame-page-navigationhelper-suspensionmanager.aspx

Windows 8.1 App C＃XAML帮助：导航回上一页时保存单选按钮选择

1 个答案: