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Change color when selected on UWP C#

I need to change the color of a rectangle in a GridView when the item is selected.
Unselected item
Selected item
My Main Page in XAML.
<Page
x:Class="GridViewWithSelectedItem.Views.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:views="using:GridViewWithSelectedItem.Views"
Style="{StaticResource PageStyle}"
mc:Ignorable="d">
<Page.Resources>
<DataTemplate x:Key="TileTemplate" x:DataType="views:Article">
<Border BorderThickness="2,2,2,2" BorderBrush="#FF868484" Margin="3,3,3,3" HorizontalAlignment="Stretch" MaxWidth="600" MinWidth="525">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="10"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition/>
<RowDefinition Height="60"/>
<RowDefinition/>
</Grid.RowDefinitions>
<Rectangle Fill="Black" Grid.RowSpan="3"/>
<StackPanel Orientation="Horizontal" Grid.Row="0" Grid.Column="1">
<TextBlock FontSize="20" Margin="0,0,5,0" TextWrapping="Wrap" Foreground="DarkBlue" FontWeight="Bold" Text="{x:Bind Number}"/>
<TextBlock FontSize="20" TextWrapping="Wrap" Foreground="DarkBlue" Text="{x:Bind Title}" FontWeight="Bold"/>
</StackPanel>
<TextBlock Grid.Row="1" Grid.Column="1" FontSize="20" Text="{x:Bind Description}" TextWrapping="WrapWholeWords"/>
<StackPanel Background="LightBlue" Padding="5,0,0,0" Grid.Row="2" Grid.Column="1">
<StackPanel Orientation="Horizontal">
<TextBlock FontSize="20" Margin="0,0,5,0" TextWrapping="Wrap">Date :</TextBlock>
<TextBlock Foreground="Red" FontSize="20" TextWrapping="Wrap" Text="{x:Bind Date}" FontWeight="Bold"/>
</StackPanel>
</StackPanel>
</Grid>
</Border>
</DataTemplate>
</Page.Resources>
<Grid x:Name="ContentArea" Margin="{StaticResource MediumLeftRightMargin}">
<Grid Background="White" VerticalAlignment="Top" HorizontalAlignment="Stretch" Margin="0,25,0,0">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="600"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="60"/>
<RowDefinition Height="800"/>
</Grid.RowDefinitions>
<TextBlock Text="The Guardian" FontSize="35" FontWeight="Bold" Grid.ColumnSpan="2" HorizontalAlignment="Center"/>
<GridView
BorderThickness="2,2,0,2" BorderBrush="#FF868484"
MinWidth="600"
Grid.Column="0"
Grid.Row="1"
Padding="5,5,5,5"
HorizontalAlignment="Center"
CanDragItems="False"
IsItemClickEnabled="true"
IsTapEnabled="False"
IsSwipeEnabled="False"
ItemsSource="{x:Bind Articles}"
ItemTemplate="{StaticResource TileTemplate}"
SelectedItem="{x:Bind Mode=TwoWay, Path=SelectedArticle}"
/>
<RelativePanel Grid.Row="1" Grid.Column="1" Background="WhiteSmoke" BorderThickness="2" BorderBrush="#FF868484" Padding="10">
<Grid RelativePanel.AlignLeftWithPanel="True" RelativePanel.AlignRightWithPanel="True">
<Grid VerticalAlignment="Top">
<Grid.ColumnDefinitions>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition/>
<RowDefinition/>
</Grid.RowDefinitions>
<StackPanel Orientation="Horizontal" Grid.Row="0">
<TextBlock FontSize="20" Margin="0,0,5,0" TextWrapping="Wrap" Foreground="DarkBlue" FontWeight="Bold" Text="{x:Bind Path=SelectedArticle.Number, Mode=OneWay}"/>
<TextBlock FontSize="20" TextWrapping="Wrap" Foreground="DarkBlue" Text="{x:Bind Path=SelectedArticle.Title, Mode=OneWay}" FontWeight="Bold"/>
</StackPanel>
<TextBlock Grid.Row="1" FontSize="20" Text="{x:Bind Path=SelectedArticle.Description, Mode=OneWay}" TextWrapping="WrapWholeWords"/>
</Grid>
</Grid>
<RelativePanel Background="LightBlue" Padding="5,0,0,0" RelativePanel.AlignBottomWithPanel="True" RelativePanel.AlignLeftWithPanel="True" RelativePanel.AlignRightWithPanel="True">
<StackPanel Orientation="Horizontal">
<TextBlock FontSize="20" Margin="0,0,5,0" TextWrapping="Wrap">Date :</TextBlock>
<TextBlock Foreground="Red" FontSize="20" TextWrapping="Wrap" Text="{x:Bind Path=SelectedArticle.Date, Mode=OneWay}" FontWeight="Bold"/>
</StackPanel>
</RelativePanel>
</RelativePanel>
</Grid>
</Grid>
</Page>
And the class of my XAML Page.
using System;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Runtime.CompilerServices;
using Windows.UI.Xaml.Controls;
namespace GridViewWithSelectedItem.Views
{
public sealed partial class MainPage : Page, INotifyPropertyChanged
{
public ObservableCollection<Article> Articles;
private Article _selectedArticle;
public Article SelectedArticle
{
get { return _selectedArticle; }
set { Set(ref _selectedArticle, value); }
}
public MainPage()
{
InitializeComponent();
Articles = new ObservableCollection<Article>();
Articles.Add(new Article(0, "Uighurs", "Being young' leads to detention in China's Xinjiang region", DateTime.Parse("09/12/2020")));
Articles.Add(new Article(1, "Brexit", "Chances of Brexit deal hang on Boris Johnson and Ursula von der Leyen dinner", DateTime.Parse("09/12/2020")));
Articles.Add(new Article(2, "Environment", "Secretive ‘gold rush’ for deep-sea mining dominated by handful of firms", DateTime.Parse("09/12/2020")));
Articles.Add(new Article(3, "Juukan Gerge induiry", "Juukan Gorge inquiry: Rio Tinto's decision to blow up Indigenous rock shelters 'inexcusable'", DateTime.Parse("09/12/2020")));
Articles.Add(new Article(4, "Australia", "British journalist uncovered Australian woman's alleged plan to kill parents on dark web, police say", DateTime.Parse("09/12/2020")));
Articles.Add(new Article(5, "Coronavirus", "Nine out of 10 in poor nations to miss out on inoculation as west buys up Covid vaccines", DateTime.Parse("09/12/2020")));
}
public event PropertyChangedEventHandler PropertyChanged;
private void Set<T>(ref T storage, T value, [CallerMemberName]string propertyName = null)
{
if (Equals(storage, value))
{
return;
}
storage = value;
OnPropertyChanged(propertyName);
}
private void OnPropertyChanged(string propertyName) => PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
public class Article
{
public int Number { get; set; }
public string Title { get; set; }
public string Description { get; set; }
public DateTime Date { get; set; }
public Article(int number, string title, string description, DateTime date)
{
Number = number;
Title = title;
Description = description;
Date = Date;
}
}
}
I see AutomationProperty.name can help me but i don't understand how to use it.
I found a way to change the color of a selected item in my class but i need to recreate the collection and i cost lot of resources. I think its possible to make it in XAML code.
Edit: I made a simple exemple of my code.
OneDrive link

You could add a Brush property into the Article class, and bind the Brush property to Rectangle.Fill property of your DataTemplate to change the color when an item of GridView control is selected.
Please check the following code:
In DataTemplate of your xaml file:
<Rectangle x:Name="rectangle" Fill="{x:Bind Brush}" Grid.RowSpan="3"/>
……
<GridView …… SelectionChanged="GridView_SelectionChanged" />
In code-behind:
public class Article
{
……
public SolidColorBrush Brush { get; set; }
public Article(int number, string title, string description, DateTime date)
{
……
Brush = new SolidColorBrush(Colors.Black);
}
}
Add a _preSelectedArticle property to save the previous item in MainPage class:
private Article _preSelectedArticle;
Change the value of Brush property of selected item and previous selected item:
private void GridView_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
if(_preSelectedArticle==null)
{
SelectedArticle.Brush.Color = Colors.Green;
_preSelectedArticle = SelectedArticle;
}
if (_preSelectedArticle!=null&&_preSelectedArticle!= SelectedArticle)
{
_preSelectedArticle.Brush.Color = Colors.Black;
SelectedArticle.Brush.Color = Colors.Green;
_preSelectedArticle = SelectedArticle;
}
}

Databinding to command inside of listview not working in UWP/MVVM-Light

I want to have a Delete button for every element in my ListView, I searched stackoverflow but none answer my question.
I tried giving my ListView a x:Name="QuizListView" and using ElementName inside the ListView to bind the command to the button.
QuizOverview.xaml
<Page
x:Name="QuizOverviewPage"
x:Class="UwpApp.View.QuizOverview"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:UwpApp.View"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
Background="{ThemeResource ApplicationPageBackgroundThemeBrush}"
DataContext="{Binding QuizOverviewInstance, Source={StaticResource Locator}}">
<StackPanel Margin="20">
<TextBlock Text="Quizzen" FontSize="48"/>
<ListView x:Name="QuizListView" ItemsSource="{Binding Quizzes}" Margin="0,20" SelectionMode="Single" SelectionChanged="QuizListView_SelectionChanged">
<ListView.ItemTemplate>
<DataTemplate>
<ListViewItem>
<StackPanel Orientation="Horizontal">
<Border CornerRadius="10" BorderBrush="Black" BorderThickness="2" Height="100" Width="400" VerticalAlignment="Center">
<TextBlock Text="{Binding Name}" VerticalAlignment="Center" HorizontalAlignment="Center" FontSize="36"></TextBlock>
</Border>
<Button VerticalAlignment="Center" Padding="20" Margin="20">Edit</Button>
<Button VerticalAlignment="Center" Padding="20" Margin="0" Command="{Binding Path=DataContext.DeleteQuizCommand, ElementName=QuizListView}" CommandParameter="{Binding}">Delete</Button>
</StackPanel>
</ListViewItem>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<Button Padding="20" Command="{Binding CreateQuizCommand}">Add New Quiz</Button>
</StackPanel>
</Page>
QuizOverviewViewModel.cs
public class QuizOverviewViewModel : ViewModelBase
{
public string Title { get; set; }
public ObservableCollection<Quiz> Quizzes { get; set; }
public RelayCommand<Quiz> DeleteQuizCommand { get; set; }
public RelayCommand CreateQuizCommand { get; set; }
public QuizOverviewViewModel()
{
Title = "Quizzen";
Quizzes = new ObservableCollection<Quiz> { new Quiz(1, "Test Quiz 1"), new Quiz(2, "Test Quiz 2"), new Quiz(3, "Test Quiz 3") };
DeleteQuizCommand = new RelayCommand<Quiz>(DeleteQuiz);
CreateQuizCommand = new RelayCommand(CreateQuizTest);
}
public void DeleteQuiz(Quiz quiz)
{
Quizzes.Remove(Quizzes.Single(i => i.Id == quiz.Id));
}
public void CreateQuizTest()
{
Quizzes.Add(new Quiz(4, "Test Quiz Creation!"));
}
}
Quiz.cs
namespace UwpApp.Model
{
public class Quiz
{
public long Id { get; set; }
public string Name { get; set; }
public Quiz(long id, string name)
{
Id = id;
Name = name;
}
}
}
The Button does nothing with my current code, while the command does work outside of the ListView.

Databinding to command inside of listview not working in UWP/MVVM-Light
The problem is that you insert ListViewItem in to DataTemplate. It will cause that ListViewItem contains sub-ListViewItem in the Visual Tree and you could not access correct DataContext with element name in your button. Please remove ListViewItem from your code.
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Border CornerRadius="10" BorderBrush="Black" BorderThickness="2" Height="100" Width="400" VerticalAlignment="Center">
<TextBlock Text="{Binding Name}" VerticalAlignment="Center" HorizontalAlignment="Center" FontSize="36"></TextBlock>
</Border>
<Button VerticalAlignment="Center" Padding="20" Margin="20">Edit</Button>
<Button VerticalAlignment="Center" Padding="20" Margin="0" Command="{Binding Path=DataContext.DeleteQuizCommand, ElementName=QuizListView}" CommandParameter="{Binding}">Delete</Button>
</StackPanel>
</DataTemplate>

LongListSelector Data Binding Issue

I am a beginner in windows Windows phone programming.
i am trying to implement LongListSelector to display group by products.
here are my classes :
public class ProductMaster {
public string Name { get; set; }
public List<ProductSubMaster> Models { get; set; }
}
public class ProductSubMaster
{
public string Name { get; set; }
public ProductSubMasterProperty modelProperty { get; set; }
}
public class ProductSubMasterProperty{
public string ProNo { get; set; }
public Uri ProImage { get; set; }
}
and my xaml :
<phone:LongListSelector
x:Name="ProductList"
ItemsSource="{Binding objProduct}"
Background="Transparent"
LayoutMode="List"
IsGroupingEnabled="True"
HideEmptyGroups ="False">
<phone:LongListSelector.GroupHeaderTemplate>
<DataTemplate>
<Border Background="Transparent" Padding="5">
<Border Background="Black" BorderBrush="Black" BorderThickness="2" Width="500"
Height="62" Margin="0,0,18,0" HorizontalAlignment="Left">
<TextBlock Text="{Binding Path=[0].Name}" Foreground="White" FontSize="25" Padding="10"
FontFamily="{StaticResource PhoneFontFamilySemiLight}" HorizontalAlignment="Center" VerticalAlignment="Center"/>
</Border>
</Border>
</DataTemplate>
</phone:LongListSelector.GroupHeaderTemplate>
<phone:LongListSelector.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Image x:Name="searchimg" HorizontalAlignment="Left" VerticalAlignment="Center" Margin="10,0,0,0" Source="{Binding Path=Models.modelProperty.ProImage}" Height="100" Width="100" ></Image>
<TextBlock x:Name="ProductName" Margin="20,0,0,0" HorizontalAlignment="Center" VerticalAlignment="Center" Width="250" TextWrapping="Wrap" Foreground="Black" Text="{Binding Path=Models.Name}" FontSize="30"></TextBlock>
<Image x:Name="bookmarkimg" HorizontalAlignment="Right" Margin="0,0,0,0" VerticalAlignment="Center" Source="/Assets/Media/star.png" Height="40" Width="30" Stretch="Uniform" ></Image>
</StackPanel>
</DataTemplate>
</phone:LongListSelector.ItemTemplate>
</phone:LongListSelector>
i am facing the issue for binding ItemTemplate
Please help me out
Thank you.

i have added listbox in itemtemplate solved my issue
here is my updated code
<phone:LongListSelector.ItemTemplate>
<DataTemplate>
<ListBox x:Name="LstFeaturesData" Visibility="Visible" ItemsSource="{Binding Path=Models}" Margin="0,0">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Image x:Name="searchimg" HorizontalAlignment="Left" VerticalAlignment="Center" Margin="10,0,0,0" Source="{Binding Path=modelProperty.ProImage}" Height="100" Width="100" ></Image>
<TextBlock x:Name="ProductName" Margin="20,0,0,0" HorizontalAlignment="Center" VerticalAlignment="Center" Width="250" TextWrapping="Wrap" Foreground="Black" Text="{Binding Path=Name}" FontSize="30"></TextBlock>
<Image x:Name="bookmarkimg" HorizontalAlignment="Right" Margin="0,0,0,0" VerticalAlignment="Center" Source="/Assets/Media/star.png" Height="40" Width="30" Stretch="Uniform" ></Image>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</DataTemplate>
</phone:LongListSelector.ItemTemplate>

Values from database not showing up on xaml page after using groupby statement

I have a dto,method and xaml file below. The method returns duplicates which is fine. I only want to display one on my xaml page. I used a groupby and I was able
to display one item but the values for RouteNbr and Day are not displayed on the xaml page.
Do you know what am doing wrong?
public class CSDto
{
public Int32 ID { get; set; }
public Int32 RouteNbr { get; set; }
public Int32 Day { get; set; }
public String Month { get; set; }
public String Year { get; set; }
}
private void GetAllCsrActPlansByCsrId(Int32 CssId)
{
try
{
string getCs = Convert.ToString(CssId);
var getRouteInfoProfile = MySol.GetByCustomerNbr(getCs);
var queryResult = getRouteInfoProfile;
grdVwRouteAct.DataContext = queryResult.GroupBy(g=>g.RouteNbr).Distinct();
}
catch (Exception ex)
{
customutility.ApplicationErrorlog(UserID, ex.Message, DateTime.Now.ToString());
}
}
<GridView.ItemTemplate>
<DataTemplate>
<Button Style="{StaticResource CSRProfile}" Margin="0" Padding="0" Height="Auto" Width="Auto" Background="MediumAquamarine">
<StackPanel Tag="cpActionPlanBlock" Width="275" Height="90" HorizontalAlignment="Left" VerticalAlignment="Center" Orientation="Horizontal" Margin="0">
<Image Source="/Assets/Images/CSRProfile-checkicon.gif" Width="49" Height="65" VerticalAlignment="Center" Margin="10"/>
<StackPanel Orientation="Vertical" VerticalAlignment="Center" Margin="10,0">
<StackPanel Orientation="Horizontal">
<TextBlock Tag="cpRouteNumber" Style="{ThemeResource BasicFontStyle4B}" Text="{Binding RouteNbr}" VerticalAlignment="Top" Margin="0,0,0,5"/>
<TextBlock Style="{ThemeResource BasicFontStyle4B}" Text="-" VerticalAlignment="Top" Margin="5,0,5,0"/>
<TextBlock Tag="cpDay" x:Uid="queueItemType" Style="{ThemeResource BasicFontStyle4B}" Text="{Binding Day}" VerticalAlignment="Top" Margin="0,0,0,5"/>
</StackPanel>
<StackPanel Orientation="Horizontal">
<TextBlock Tag="cpNumberofActions" Style="{ThemeResource BasicFontStyle4B}" Text="[Y]" VerticalAlignment="Top" Margin="0,0,5,0"/>
<TextBlock Tag="cpLblActions" Style="{ThemeResource BasicFontStyle4B}" Text="Actions" x:Uid="cpActions" VerticalAlignment="Top" Margin="0,0,15,5"/>
</StackPanel>
</StackPanel>
</StackPanel>
</Button>
</DataTemplate>
</GridView.ItemTemplate>

Windows Phone 8.1 Hub Section Update Items (INotifyPropertyChanged)

I am trying to build a diary app that uses hub as user interface and update the UI after saving the diary. I already implemented the INotifyPropertyChanged but it didn't work. I want the item that is added after saving to appear on the hub immediately.
public class SampleDataGroup : INotifyPropertyChanged
{
public SampleDataGroup()
{
UniqueId = string.Empty;
Title = string.Empty;
Subtitle = string.Empty;
Description = string.Empty;
ImagePath = string.Empty;
Items = new ObservableCollection<DiaryData>();
}
public string UniqueId { get; private set; }
public string Title { get; private set; }
public string Subtitle { get; private set; }
public string Description { get; private set; }
public string ImagePath { get; private set; }
private ObservableCollection<DiaryData> _items;
public ObservableCollection<DiaryData> Items { get{return _items;} private set
{
OnPropertyChanged("Items");
_items = value;
} }
public override string ToString()
{
if (this.Title != null)
{
return this.Title;
}
else
{
System.Diagnostics.Debug.WriteLine("this is null at tostring");
return null;
}
}
public event PropertyChangedEventHandler PropertyChanged;
public void OnPropertyChanged(string name)
{
PropertyChangedEventHandler handler = PropertyChanged;
if (handler != null)
{
handler(this, new PropertyChangedEventArgs(name));
}
}
}
public sealed class SampleDataSource : INotifyPropertyChanged
{
private static SampleDataSource _sampleDataSource = new SampleDataSource();
private ObservableCollection<SampleDataGroup> _groups = new ObservableCollection<SampleDataGroup>();
public ObservableCollection<SampleDataGroup> Groups
{
get { return this._groups; }
set { }
}
public static async Task<IEnumerable<SampleDataGroup>> GetGroupsAsync()
{
await _sampleDataSource.GetSampleDataAsync();
return _sampleDataSource.Groups;
}
public static async Task<SampleDataGroup> GetGroupAsync(string uniqueId)
{
System.Diagnostics.Debug.WriteLine("GetGroupAsync is entered phase 1");
await _sampleDataSource.GetSampleDataAsync();
// Simple linear search is acceptable for small data sets
System.Diagnostics.Debug.WriteLine("GetGroupAsync is entered phase 2");
var matches = _sampleDataSource.Groups.Where((group) => group.UniqueId.Equals(uniqueId));
if (matches.Count() == 1) return matches.First();
return null;
}
public static async Task<DiaryData> GetItemAsync(string uniqueId)
{
await _sampleDataSource.GetSampleDataAsync();
System.Diagnostics.Debug.WriteLine("GetItemAsync is entered");
// Simple linear search is acceptable for small data sets
var matches = _sampleDataSource.Groups.SelectMany(group => group.Items).Where((item) => item.UniqueId.Equals(uniqueId));
if (matches.Count() == 1) return matches.First();
else return null;
}
private async Task GetSampleDataAsync()
{
System.Diagnostics.Debug.WriteLine("GetSampleDataAsync is entered");
//if (this._groups.Count != 0)return;
Uri dataUri = new Uri("ms-appdata:///local/data.json");
StorageFile file = await StorageFile.GetFileFromApplicationUriAsync(dataUri);
string jsonText = await FileIO.ReadTextAsync(file);
JsonArray jsonArray = JsonArray.Parse(jsonText);
SampleDataGroup group = new SampleDataGroup();
foreach (JsonValue itemValue in jsonArray)
{
JsonObject itemObject = itemValue.GetObject();
group.Items.Add(new DiaryData(itemObject["Title"].GetString(),
itemObject["Content"].GetString(),
itemObject["Coordinate"].GetString(),
itemObject["UniqueId"].GetString(),
itemObject["ImagePath"].GetString(),
itemObject["VideoPath"].GetString()));
System.Diagnostics.Debug.WriteLine(itemObject["Title"].GetString());
}
this.Groups.Add(group);
System.Diagnostics.Debug.WriteLine("GetSampleDataAsync is finished");
}
//}
public event PropertyChangedEventHandler PropertyChanged;
}
here's my XAML File
<Page
x:Class="DiaryAppHub.HubPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:DiaryAppHub"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:data="using:DiaryAppHub.Data"
DataContext="{Binding DefaultViewModel, RelativeSource={RelativeSource Self}}"
d:DataContext="{Binding Source={d:DesignData Source=/DataModel/SampleData.json, Type=data:data.json}}"
mc:Ignorable="d">
<Page.Resources>
<DataTemplate x:Key="HubSectionHeaderTemplate">
<TextBlock Margin="0,0,0,-9.5" Text="{Binding}"/>
</DataTemplate>
<!-- Grid-appropriate item template as seen in section 2 -->
<DataTemplate x:Key="Standard200x180TileItemTemplate">
<Grid Margin="0,0,9.5,9.5" Background="{ThemeResource ListViewItemPlaceholderBackgroundThemeBrush}">
<Image Source="{Binding ImagePath}" Stretch="UniformToFill" AutomationProperties.Name="{Binding Title}" Height="138.5" Width="138.5"/>
<TextBlock Text="{Binding Title}" VerticalAlignment="Bottom" Margin="9.5,0,0,6.5" Style="{ThemeResource BaseTextBlockStyle}"/>
</Grid>
</DataTemplate>
<DataTemplate x:Key="StandardTripleLineItemTemplate">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Border Background="{ThemeResource ListViewItemPlaceholderBackgroundThemeBrush}" Margin="0,9.5,0,0" Grid.Column="0" HorizontalAlignment="Left">
<Image Source="{Binding ImagePath}" Stretch="UniformToFill" AutomationProperties.Name="{Binding Title}" Height="79" Width="79"/>
</Border>
<StackPanel Grid.Column="1" Margin="14.5,0,0,0">
<TextBlock Text="{Binding Title}" Style="{ThemeResource ListViewItemTextBlockStyle}"/>
<TextBlock Text="{Binding Description}" Style="{ThemeResource ListViewItemContentTextBlockStyle}" Foreground="{ThemeResource PhoneMidBrush}" />
<TextBlock Text="{Binding Subtitle}" Style="{ThemeResource ListViewItemSubheaderTextBlockStyle}" />
</StackPanel>
</Grid>
</DataTemplate>
<DataTemplate x:Key="StandardDoubleLineItemTemplate">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Border Background="{ThemeResource ListViewItemPlaceholderBackgroundThemeBrush}" Margin="0,9.5,0,0" Grid.Column="0" HorizontalAlignment="Left">
<Image Source="{Binding ImagePath}" Stretch="UniformToFill" AutomationProperties.Name="{Binding Title}" Height="79" Width="79"/>
</Border>
<StackPanel Grid.Column="1" Margin="14.5,0,0,0">
<TextBlock Text="{Binding Title}" Style="{ThemeResource ListViewItemTextBlockStyle}" Foreground="Black"/>
<TextBlock Text="{Binding Subtitle}" Style="{ThemeResource ListViewItemSubheaderTextBlockStyle}" Foreground="DimGray"/>
</StackPanel>
</Grid>
</DataTemplate>
</Page.Resources>
<Page.BottomAppBar>
<CommandBar Background="Transparent">
<AppBarButton Icon="Add" Label="Add" Click="add_onclick"/>
<AppBarButton Icon="Add" Label="Shake it!" />
</CommandBar>
</Page.BottomAppBar>
<Grid x:Name="LayoutRoot">
<Hub x:Name="Hub" x:Uid="Hub" Header="diary app hub" Margin="0,0,0,-59" Foreground="DimGray">
<Hub.Background>
<ImageBrush ImageSource="ms-appx:/Assets/desk_paper.png" Stretch="None"/>
</Hub.Background>
<!--<HubSection x:Uid="HubSection1" Header="SECTION 1" DataContext="{Binding Groups}" HeaderTemplate="{ThemeResource HubSectionHeaderTemplate}">
<DataTemplate>
<ListView
ItemsSource="{Binding}"
IsItemClickEnabled="True"
ItemClick="GroupSection_ItemClick"
ContinuumNavigationTransitionInfo.ExitElementContainer="True">
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel Margin="0,0,0,27.5">
<TextBlock Text="{Binding Title}" Style="{ThemeResource ListViewItemTextBlockStyle}" />
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</DataTemplate>
</HubSection>-->
<HubSection x:Uid="HubSection5" Header="Recent"
DataContext="{Binding Groups[0]}" HeaderTemplate="{ThemeResource HubSectionHeaderTemplate}">
<DataTemplate>
<ListView
AutomationProperties.AutomationId="ItemListViewSection5"
AutomationProperties.Name="Items In Group"
SelectionMode="None"
IsItemClickEnabled="True"
ItemsSource="{Binding Items}"
ItemTemplate="{StaticResource StandardDoubleLineItemTemplate}"
ItemClick="ItemView_ItemClick"
ContinuumNavigationTransitionInfo.ExitElementContainer="True">
</ListView>
</DataTemplate>
</HubSection>
<HubSection x:Uid="HubSection2" Header="All notes" Width ="Auto"
DataContext="{Binding Groups[0]}" HeaderTemplate="{ThemeResource HubSectionHeaderTemplate}" Height="659" >
<DataTemplate>
<GridView
Margin="0,9.5,0,0"
ItemsSource="{Binding Items}"
AutomationProperties.AutomationId="ItemGridView"
AutomationProperties.Name="Items In Group"
ItemTemplate="{StaticResource Standard200x180TileItemTemplate}"
SelectionMode="None"
IsItemClickEnabled="True"
ItemClick="ItemView_ItemClick"
ContinuumNavigationTransitionInfo.ExitElementContainer="True">
<GridView.ItemsPanel>
<ItemsPanelTemplate>
<ItemsWrapGrid />
</ItemsPanelTemplate>
</GridView.ItemsPanel>
</GridView>
</DataTemplate>
</HubSection>
</Hub>
</Grid>

You need to raise the PropertyChanged event for the model's properties. The UI doesn't get notified as properties like Title,Subtitle don't raise the PropertyChanged event when they are modified. It should be like this:
private string _title;
public string Title
{
get
{
return _title;
}
set
{
if(_title!=value)
{
_title=value;
OnPropertyChanged("Title");
}
}
}
Do this similarly for other properties. Also, you don't need to raise the PropertyChanged event for an ObservableCollection as an ObservableCollection implements INotifyPropertyChanged by default.