MVVM Light Bind value to list on button click

Question

I am trying to build an simple universal app and I have followed the MVVM light setup. So far everything has fallen in place. Now I have a button and a listview on the same page. What I am trying to achieve is when I click on the button I want the list
view to show values. I have the list view bound to an observable collection and the button bound to RelayCommand. When I click the button the relay command is executing and returning values which I add to the observable collection, but myview is not getting
updated. when i directly create object in my design mode and in runtime the view is updating properly. Please provide any suggestion.
Code Section
View
<Page
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:CorrectMetroCardFare"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:ViewModel="using:CorrectMetroCardFare.ViewModel"
    x:Class="CorrectMetroCardFare.MainPage"
    mc:Ignorable="d"
    Background="{ThemeResource ApplicationPageBackgroundThemeBrush}"
    DataContext="{Binding Main, Mode=OneWay, Source={StaticResource Locator}}">
    <Grid Height="640" Margin="0,0.333,0,-0.333" VerticalAlignment="Top">
        <TextBlock x:Name="title" Text="Metro Card Fare"  Margin="0,10,0,603"/>
        <TextBox x:Name="txtCurrentValue" InputScope="Number" PlaceholderText="Enter your Current Balance" Margin="0,53,0,0" Text="{Binding CurrentBalance, Mode=TwoWay}"/>
        <Button Content="Show Fares" HorizontalAlignment="Left" Margin="96,113,0,0" VerticalAlignment="Top" Command="{Binding ShowFaresCommand, Mode=OneWay}" CommandParameter="{Binding
CurrentBalance}" />
        <ListView x:Name="nbc" SelectionMode="Single" Margin="10,182,10,150" ItemsSource="{Binding Charges}">
            <ListView.Resources>
                <DataTemplate x:Key="FareTemplate">
                    <Grid>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="*" />
                        </Grid.ColumnDefinitions>
                        <TextBlock Text="{Binding AmountToRecharge}" TextAlignment="Right" Grid.ColumnSpan="4"
Margin="0,0,-28,0" FontFamily="{StaticResource PhoneFontFamilyNormal}" FontSize="{StaticResource TextStyleLargeFontSize}"></TextBlock>
                        <TextBlock Text="{Binding BonusAmount}" TextAlignment="Right" Margin="118.333,0,-128.333,0"
Grid.Column="3" FontSize="{StaticResource TextStyleLargeFontSize}"/>
                        <TextBlock Text="{Binding NewBalance}" TextAlignment="Right" Margin="118,0,-229.333,0"
Grid.Column="3" FontSize="{StaticResource TextStyleLargeFontSize}"/>
                        <TextBlock Text="{Binding NumberofRides}" TextAlignment="Right" Margin="298,0,-308.333,0"
Grid.Column="3" FontSize="{StaticResource TextStyleLargeFontSize}"/>
                    </Grid>
                </DataTemplate>
                <ItemsPanelTemplate x:Key="FaresPanelTemplate">
                    <VirtualizingStackPanel Orientation="Vertical"></VirtualizingStackPanel>
                </ItemsPanelTemplate>
                <DataTemplate x:Key="headerTemplate">
                    <Grid>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="90" />
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="*" />
                        </Grid.ColumnDefinitions>
                        <TextBlock Text="Amount to Recharge" Grid.Column="0" TextWrapping="WrapWholeWords" FontFamily="{StaticResource
PivotHeaderItemFontFamily}" FontSize="{StaticResource ContentControlFontSize}"/>
                        <TextBlock Text="Bonus Amount" Grid.Column="1" TextWrapping="WrapWholeWords" FontFamily="{StaticResource
PivotHeaderItemFontFamily}" FontSize="{StaticResource ContentControlFontSize}"/>
                        <TextBlock Text="New Balance" Grid.Column="2" TextWrapping="WrapWholeWords" FontFamily="{StaticResource
PivotHeaderItemFontFamily}" FontSize="{StaticResource ContentControlFontSize}"/>
                        <TextBlock Text="Number of Rides" Grid.Column="3" TextWrapping="WrapWholeWords" FontFamily="{StaticResource
PivotHeaderItemFontFamily}" FontSize="{StaticResource ContentControlFontSize}"/>
                    </Grid>
                </DataTemplate>
            </ListView.Resources>
            <ListView.HeaderTemplate>
                <StaticResource ResourceKey="headerTemplate"/>
            </ListView.HeaderTemplate>
            <ListView.ItemsPanel>
                <StaticResource ResourceKey="FaresPanelTemplate"/>
            </ListView.ItemsPanel>
            <ListView.ItemTemplate>
                <StaticResource ResourceKey="FareTemplate"/>
            </ListView.ItemTemplate>
            <ListView.DataContext>
                <ViewModel:MainViewModel/>
            </ListView.DataContext>
        </ListView>
    </Grid>
</Page>
View Model
     /// <summary>
                /// Sets and gets the DayList property.
                /// Changes to that property's value raise the PropertyChanged event.
                /// </summary>
                public ObservableCollection<BonusChargesValue> Charges
                    get
                        return _charges;
                    set
                        if (_charges == value)
                            return;
                       // RaisePropertyChanging(ChargesListPropertyName);
                        _charges = value;
                        RaisePropertyChanged(ChargesListPropertyName);
                public RelayCommand ShowFaresCommand
                    get;
                    set;
          /// <summary>
                /// Initializes a new instance of the MainViewModel class.
                /// </summary>
                public MainViewModel()
                    if (IsInDesignMode)
                        // Code runs in Blend --> create design time data.
                       // BonusChargesValue bnc = new BonusChargesValue();
                        _charges = new ObservableCollection<BonusChargesValue>();
                        _charges.Add(new BonusChargesValue { AmountToRecharge = 10.0, BonusAmount = 5, NewBalance = 15, NumberofRides = 5 });
                        _charges.Add(new BonusChargesValue { AmountToRecharge = 12.0, BonusAmount = 6, NewBalance = 17, NumberofRides = 6 });
                        _charges.Add(new BonusChargesValue { AmountToRecharge = 14.0, BonusAmount = 7, NewBalance = 19, NumberofRides = 7 });
                        _charges.Add(new BonusChargesValue { AmountToRecharge = 16.0, BonusAmount = 8, NewBalance = 21, NumberofRides = 8 });
                        _charges.Add(new BonusChargesValue { AmountToRecharge = 18.0, BonusAmount = 9, NewBalance = 23, NumberofRides = 9 });
                        _charges.Add(new BonusChargesValue { AmountToRecharge = 10.0, BonusAmount = 5, NewBalance = 15, NumberofRides = 5 });
                        _charges.Add(new BonusChargesValue { AmountToRecharge = 12.0, BonusAmount = 6, NewBalance = 17, NumberofRides = 6 });
                        _charges.Add(new BonusChargesValue { AmountToRecharge = 14.0, BonusAmount = 7, NewBalance = 19, NumberofRides = 7 });
                        _charges.Add(new BonusChargesValue { AmountToRecharge = 16.0, BonusAmount = 8, NewBalance = 21, NumberofRides = 8 });
                        _charges.Add(new BonusChargesValue { AmountToRecharge = 18.0, BonusAmount = 9, NewBalance = 23, NumberofRides = 9 });
                    else
                        // Code runs "for real"
                        Charges = new ObservableCollection<BonusChargesValue>();
                        ShowFaresCommand = new RelayCommand(GetValues, () => { return true; });
                      //  ShowFares = new RelayCommand(() =>
                           // Words = new string(Words.ToCharArray().Reverse().ToArray());
                        //_charges = new ObservableCollection<BonusChargesValue>();
                        //_charges.Add(new BonusChargesValue { AmountToRecharge = 10.0, BonusAmount = 5, NewBalance = 15, NumberofRides = 5 });
                        //_charges.Add(new BonusChargesValue { AmountToRecharge = 12.0, BonusAmount = 6, NewBalance = 17, NumberofRides = 6 });
                        //_charges.Add(new BonusChargesValue { AmountToRecharge = 14.0, BonusAmount = 7, NewBalance = 19, NumberofRides = 7 });
                        //_charges.Add(new BonusChargesValue { AmountToRecharge = 16.0, BonusAmount = 8, NewBalance = 21, NumberofRides = 8 });
                        //_charges.Add(new BonusChargesValue { AmountToRecharge = 18.0, BonusAmount = 9, NewBalance = 23, NumberofRides = 9 });
                        //_charges.Add(new BonusChargesValue { AmountToRecharge = 10.0, BonusAmount = 5, NewBalance = 15, NumberofRides = 5 });
                        //_charges.Add(new BonusChargesValue { AmountToRecharge = 12.0, BonusAmount = 6, NewBalance = 17, NumberofRides = 6 });
                        //_charges.Add(new BonusChargesValue { AmountToRecharge = 14.0, BonusAmount = 7, NewBalance = 19, NumberofRides = 7 });
                        //_charges.Add(new BonusChargesValue { AmountToRecharge = 16.0, BonusAmount = 8, NewBalance = 21, NumberofRides = 8 });
                        //_charges.Add(new BonusChargesValue { AmountToRecharge = 18.0, BonusAmount = 9, NewBalance = 23, NumberofRides = 9 });
                private void GetValues()
                    CalculateMetroFare cmcf = new CalculateMetroFare();
                    if (!string.IsNullOrWhiteSpace(CurrentBalance))
                        var chr = cmcf.Add2ExistingCard(Convert.ToInt32(CurrentBalance));
                        foreach (BonusChargesValue bncv in chr)
                            Charges.Add(bncv);
                    }`enter code here`
                   // return _charges;
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VAravind ---------------------------------------------------------------------------------------------------------------------------------- Please click "Propose As Answer" if a post solves your problem or "Vote As Helpful" if a post
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Answer 1

I am not getting error but the Listview is not getting updated after the relay command
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