模板中有Button，它的值绑定到INotifyPropertyChanged，但Content在运行时不会更改。它只更新一次。但如果我从后面的代码触发更改，则不会更改它。
据我所知，我已经完全正确地设置了代码，但我可能在某处出错了。我从点击按钮显示的Flyout触发更改，但不会更改按钮内容。
我的XAML代码是：
<DataTemplate x:Key="UserUploads">
<UserControl>
<RelativePanel Name="panel"
Margin="5">
<Image Name="image"
Source="{Binding VideoThumbnail, Mode=OneWay, UpdateSourceTrigger=PropertyChanged}"/>
<TextBlock Text="{Binding VideoTitle, Mode=OneWay, UpdateSourceTrigger=PropertyChanged}"
Name="title"
Style="{StaticResource SubtitleTextBlockStyle}"
TextTrimming="CharacterEllipsis"
MaxLines="2"/>
<TextBlock Name="publish"
Text="{Binding PublishingTime, Mode=OneWay, UpdateSourceTrigger=PropertyChanged}"/>
<TextBlock Name="privacy"
Text="{Binding PrivacyStatus, Mode=OneWay, UpdateSourceTrigger=PropertyChanged}"/>
<Button Name="LikeBtn"
Background="Transparent"
RelativePanel.AlignBottomWithPanel="True"
Click="LikeBtn_Click"
Content="{Binding FavoriteBtnContent, Mode=OneWay, UpdateSourceTrigger=PropertyChanged}">
</Button>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup>
<VisualState>
<VisualState.StateTriggers>
<AdaptiveTrigger MinWindowWidth="0"/>
</VisualState.StateTriggers>
<VisualState.Setters>
<Setter Target="image.Width"
Value="144"/>
<Setter Target="image.Height"
Value="81"/>
<Setter Target="title.MaxLines"
Value="1"/>
<Setter Target="title.(RelativePanel.Below)"
Value="image"/>
<Setter Target="publish.(RelativePanel.Below)"
Value="title"/>
<Setter Target="privacy.(RelativePanel.Below)"
Value="publish"/>
<Setter Target="LikeBtn.(RelativePanel.Below)"
Value="privacy"/>
</VisualState.Setters>
</VisualState>
<VisualState>
<VisualState.StateTriggers>
<AdaptiveTrigger MinWindowWidth="550"/>
</VisualState.StateTriggers>
<VisualState.Setters>
<Setter Target="image.Width"
Value="256"/>
<Setter Target="image.Height"
Value="144"/>
<Setter Target="title.MaxLines"
Value="2"/>
<Setter Target="title.(RelativePanel.RightOf)"
Value="image"/>
<Setter Target="publish.(RelativePanel.RightOf)"
Value="image"/>
<Setter Target="privacy.(RelativePanel.RightOf)"
Value="image"/>
<Setter Target="publish.(RelativePanel.Below)"
Value="title"/>
<Setter Target="privacy.(RelativePanel.Below)"
Value="publish"/>
<Setter Target="LikeBtn.(RelativePanel.RightOf)"
Value="image"/>
</VisualState.Setters>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
</RelativePanel>
</UserControl>
</DataTemplate>
我的xaml.cs代码隐藏是：
public sealed partial class UserUploads : Page
{
public UserUploads()
{
this.InitializeComponent();
DataContext = Helpers.UserUploadedVideos.inotifyObj;
}
protected async override void OnNavigatedTo(NavigationEventArgs e)
{
base.OnNavigatedTo(e);
// load data
// load uploaded videos without live streams
Helpers.UserUploadedVideos.inotifyObj.VideoUploadsList = await Helpers.APIData.GetUserUploads(Helpers.APIData.VideoType.Uploaded);
// load uploaded live streams
Helpers.UserUploadedVideos.inotifyObj.LiveStreamsList = await Helpers.APIData.GetUserUploads(Helpers.APIData.VideoType.Live);
// load playlists
// done
}
private void LikeBtn_Click(object sender, RoutedEventArgs e)
{
var item = (Helpers.UserUploadedVideos)((FrameworkElement)e.OriginalSource).DataContext;
if (item.LikedOrNot == Helpers.UserUploadedVideos.VideoLike.none)
{
var menu1 = new MenuFlyoutItem() { Text = "Like" };
var menu2 = new MenuFlyoutItem() { Text = "Dislike" };
menu1.Click += (s, es) =>
{
LikeBtnFlyout_Click(s);
};
var panel = new StackPanel();
panel.Children.Add(menu1);
panel.Children.Add(menu2);
var flyout = new Flyout() { Content = panel };
flyout.ShowAt(sender as FrameworkElement);
}
else
{
var menu1 = new MenuFlyoutItem() { Text = "Remove Like/Dislike" };
menu1.Click += (s, es) => { LikeBtnFlyout_Click(s); };
var panel = new StackPanel();
panel.Children.Add(menu1);
var flyout = new Flyout() { Content = panel };
flyout.ShowAt(sender as FrameworkElement);
}
}
private void LikeBtnFlyout_Click(object sender)
{
var menuItem = sender as MenuFlyoutItem;
var item = new Helpers.INotifyProperty();
if (menuItem.Text == "Like")
{
// like the vide
Helpers.UserUploadedVideos.inotifyObj.FavoriteBtnContent = new FontIcon() { Glyph = Helpers.SettingsKeys.LikeIcon };
}
else if (menuItem.Text == "Dislike")
{
// dislike the video
Helpers.UserUploadedVideos.inotifyObj.FavoriteBtnContent = new FontIcon() { Glyph = Helpers.SettingsKeys.DislikeIcon };
}
else
{
// remove the like/dislike as in "none"
Helpers.UserUploadedVideos.inotifyObj.FavoriteBtnContent = "Like/Dislike";
}
}
}
我的自定义课程INotifyPropertyChanged
public class UserUploadedVideos : INotifyPropertyChanged
{
public enum VideoLike
{
like,
dislike,
none
}
public static UserUploadedVideos inotifyObj = new UserUploadedVideos();
public event PropertyChangedEventHandler PropertyChanged;
private void OnPropertyChanged([CallerMemberName] string setting = "")
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(setting));
}
private ObservableCollection<UserUploadedVideos> uploadedVideos;
public ObservableCollection<UserUploadedVideos> VideoUploadsList
{
get { return uploadedVideos; }
set
{
if (value != uploadedVideos)
{
uploadedVideos = value;
OnPropertyChanged();
}
}
}
private ObservableCollection<UserUploadedVideos> liveSreams;
public ObservableCollection<UserUploadedVideos> LiveStreamsList
{
get { return liveSreams; }
set
{
if (value != liveSreams)
{
liveSreams = value;
OnPropertyChanged();
}
}
}
private object btnContent;
public object FavoriteBtnContent
{
get
{
if (btnContent == null)
{
btnContent = "Like/Dislike";
}
return btnContent;
}
set
{
if (value != btnContent)
{
btnContent = value;
OnPropertyChanged();
}
}
}
private BitmapImage vThumbnail;
public BitmapImage VideoThumbnail
{
get { return vThumbnail; }
set
{
if (value != vThumbnail)
{
vThumbnail = value;
OnPropertyChanged();
}
}
}
private string vTitle;
public string VideoTitle
{
get { return vTitle; }
set
{
if (value != vTitle)
{
vTitle = value;
OnPropertyChanged();
}
}
}
private string publishTime;
public string PublishingTime
{
get { return publishTime; }
set
{
if (value != publishTime)
{
publishTime = value;
OnPropertyChanged();
}
}
}
private string privacyStatus;
public string PrivacyStatus
{
get { return privacyStatus; }
set
{
if (value != privacyStatus)
{
privacyStatus = value;
OnPropertyChanged();
}
}
}
private string vID;
public string VideoID
{
get { return vID; }
set
{
if (value != vID)
{
vID = value;
OnPropertyChanged();
}
}
}
private string cID;
public string ChannelID
{
get { return cID; }
set
{
if (value != cID)
{
cID = value;
OnPropertyChanged();
}
}
}
private VideoLike likeOrNot;
public VideoLike LikedOrNot
{
get { return likeOrNot; }
set
{
if (value != likeOrNot)
{
likeOrNot = value;
OnPropertyChanged();
}
}
}
private string pageToken;
public string PageToken
{
get { return pageToken; }
set
{
if (value != pageToken)
{
pageToken = value;
OnPropertyChanged();
}
}
}
}
所有其他属性都能很好地工作，因为我不需要在第一次之后更改它们，但我确实需要随时更改按钮内容。
所以请帮我理清这里出了什么问题。感谢
更新
我稍微更改了代码并将x:Bind与整个列表一起使用，并尝试从其发件人对象更新按钮并且它可以正常工作。如果我从发件人对象中更改Button内容，我可以立即看到更改。