Develop Reference

How To Add Tab Item using MVVM Light?

I have 2 XAML where the first one will shows a list of the second one during runtime. The 1st xaml code is below.
1. BrowserWindowView.xaml
<Page
x:Class="AffiliaTool.Lib.View.BrowserWindowView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:core="using:Microsoft.Xaml.Interactions.Core"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:i="using:Microsoft.Xaml.Interactivity"
xmlns:local="using:AffiliaTool.Lib.View"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:tk="using:Microsoft.Toolkit.Uwp.UI.Controls"
xmlns:vm="using:AffiliaTool.Lib.ViewModel"
mc:Ignorable="d">
<Page.DataContext>
<vm:BrowserWindowViewModel />
</Page.DataContext>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="41" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid>
<Button Width="100" Content="NEW TAB">
<i:Interaction.Behaviors>
<core:EventTriggerBehavior EventName="Click">
<core:InvokeCommandAction Command="{Binding OnNewTabClicked}" />
</core:EventTriggerBehavior>
</i:Interaction.Behaviors>
</Button>
</Grid>
<tk:TabView
Name="TabViewBar"
Grid.Row="1"
ItemsSource="{Binding Tabs, Mode=TwoWay}">
<i:Interaction.Behaviors>
<core:EventTriggerBehavior EventName="Loaded">
<core:ChangePropertyAction
PropertyName="TabViewBar"
TargetObject="{Binding}"
Value="{Binding ElementName=TabViewBar, Mode=TwoWay}" />
<core:InvokeCommandAction Command="{Binding OnTabViewLoaded}" />
</core:EventTriggerBehavior>
</i:Interaction.Behaviors>
<tk:TabView.ItemHeaderTemplate>
<DataTemplate>
<TextBlock Text="Hello Tab" />
</DataTemplate>
</tk:TabView.ItemHeaderTemplate>
<tk:TabView.ItemTemplate>
<DataTemplate>
<local:BrowserTabWidget DataContext="{Binding}" />
</DataTemplate>
</tk:TabView.ItemTemplate>
</tk:TabView>
</Grid>
</Page>
This first xaml is use to spawn a new window and displays the first WebView object in the initial tab item. The 2nd xaml code that will renders WebView is like below.
2. BrowserTabWidget.xaml
<UserControl
x:Class="AffiliaTool.Lib.View.BrowserTabWidget"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:core="using:Microsoft.Xaml.Interactions.Core"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:i="using:Microsoft.Xaml.Interactivity"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:vm="using:AffiliaTool.Lib.ViewModel"
mc:Ignorable="d">
<UserControl.DataContext>
<vm:BrowserTabViewModel />
</UserControl.DataContext>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="41" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid x:Name="Toolbar" Grid.Row="0">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="42" />
<ColumnDefinition Width="42" />
<ColumnDefinition Width="42" />
<ColumnDefinition Width="*" />
<ColumnDefinition Width="42" />
</Grid.ColumnDefinitions>
<Button Grid.Column="0" Background="Transparent">
<Button.Content>
<TextBlock
Margin="0,0,4,0"
VerticalAlignment="Center"
FontFamily="Segoe MDL2 Assets"
FontSize="18"
Foreground="#f06a35"
Text="" />
</Button.Content>
</Button>
<Button Grid.Column="1" Background="Transparent">
<Button.Content>
<TextBlock
Margin="0,0,4,0"
VerticalAlignment="Center"
FontFamily="Segoe MDL2 Assets"
FontSize="18"
Foreground="#f06a35"
Text="" />
</Button.Content>
</Button>
<Button Grid.Column="2" Background="Transparent">
<Button.Content>
<TextBlock
Margin="0,0,4,0"
VerticalAlignment="Center"
FontFamily="Segoe MDL2 Assets"
FontSize="18"
Foreground="#f06a35"
Text="" />
</Button.Content>
</Button>
<TextBox
Grid.Column="3"
Height="32"
Margin="4,0"
Background="White"
BorderBrush="#f06a35"
BorderThickness="1"
FontSize="18" />
<Button Grid.Column="4" Background="Transparent">
<Button.Content>
<TextBlock
Margin="0,0,4,0"
VerticalAlignment="Center"
FontFamily="Segoe MDL2 Assets"
FontSize="18"
Foreground="#f06a35"
Text="" />
</Button.Content>
</Button>
</Grid>
<WebView x:Name="WebBrowser" Grid.Row="1">
<i:Interaction.Behaviors>
<core:EventTriggerBehavior EventName="Loaded">
<core:ChangePropertyAction
PropertyName="WebBrowser"
TargetObject="{Binding}"
Value="{Binding ElementName=WebBrowser, Mode=TwoWay}" />
<core:InvokeCommandAction Command="{Binding OnBrowserLoaded}" />
</core:EventTriggerBehavior>
</i:Interaction.Behaviors>
</WebView>
</Grid>
</UserControl>
For the 1st xaml I have a ViewModel class code like below, and it has RelayCommand to handle "NEW TAB" button click.
namespace AffiliaTool.Lib.ViewModel
{
public class BrowserWindowViewModel : ViewModelBase
{
private List<BrowserTabViewModel> _tabs;
private RelayCommand _onNewTabClicked;
private RelayCommand _onTabViewLoaded;
private IWebScrapper _scrapper;
private TabView _tabView;
public BrowserWindowViewModel()
{
_tabs = new List<BrowserTabViewModel>();
}
public IWebScrapper Scrapper
{
set
{
_scrapper = value;
}
}
public TabView TabViewBar
{
get
{
return _tabView;
}
set
{
Set("TabViewBar", ref _tabView, value);
}
}
public List<BrowserTabViewModel> Tabs
{
get
{
return _tabs;
}
private set { }
}
public RelayCommand OnTabViewLoaded
{
get
{
return _onTabViewLoaded ?? (_onTabViewLoaded = new RelayCommand(() =>
{
Debug.WriteLine(">>> TAB VIEW LOADED...");
}));
}
}
public RelayCommand OnNewTabClicked
{
get
{
return _onNewTabClicked ?? (_onNewTabClicked = new RelayCommand(() =>
{
var tab = new BrowserTabViewModel
{
Scrapper = _scrapper
};
Tabs.Add(tab);
}));
}
}
}
}
My question is: why everytime I click the "NEW TAB" button which should add new BrowserTabViewModel object into the List and resulting additional Tab created in the UI not working? I cannot add new TAB into the TabView element in the first XAML? No error detected.
I have been struggling for 2 days now, trying to add new TabViewItem in MVVM way, or is there anymore MVVM framework that may enable this feature?

Issues creating a flipview on ItemDetailPage

I am trying to create a flipview on the an ItemDetailpage. I am using the default template provided in visual studio when creating a grid app.
Pages in the App: GroupItemsPage, GroupDetailPage, ItemDetailPage
The problem is, I am getting this error when I click on an item on the GroupItemsPage or GroupDetailPage:
Object reference not set to an instance of an object.
Error details:
System.NullReferenceException was unhandled by user code
HResult=-2147467261
Message=Object reference not set to an instance of an object.
Source=AppError
StackTrace: at AppError.ItemDetailPage.<navigationHelper_LoadState>d__0.MoveNext()
This is my code:
GroupItemsPage.xaml
<Page
x:Name="pageRoot"
x:Class="AppError.GroupedItemsPage"
DataContext="{Binding DefaultViewModel, RelativeSource={RelativeSource Self}}"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:AppError"
xmlns:data="using:AppError.Data"
xmlns:common="using:AppError.Common"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d">
<Page.Resources>
<x:String x:Key="ChevronGlyph"></x:String>
<!--
Collection of grouped items displayed by this page, bound to a subset
of the complete item list because items in groups cannot be virtualized
-->
<CollectionViewSource
x:Name="groupedItemsViewSource"
Source="{Binding Groups}"
IsSourceGrouped="true"
ItemsPath="Items"
d:Source="{Binding Groups, Source={d:DesignData Source=/DataModel/SampleData.json, Type=data:SampleDataSource}}"/>
</Page.Resources>
<!--
This grid acts as a root panel for the page that defines two rows:
* Row 0 contains the back button and page title
* Row 1 contains the rest of the page layout
-->
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<Grid.ChildrenTransitions>
<TransitionCollection>
<EntranceThemeTransition/>
</TransitionCollection>
</Grid.ChildrenTransitions>
<Grid.RowDefinitions>
<RowDefinition Height="140"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<!-- Horizontal scrolling grid -->
<GridView
x:Name="itemGridView"
AutomationProperties.AutomationId="ItemGridView"
AutomationProperties.Name="Grouped Items"
Grid.RowSpan="2"
Padding="116,137,40,46"
ItemsSource="{Binding Source={StaticResource groupedItemsViewSource}}"
SelectionMode="None"
IsSwipeEnabled="false"
IsItemClickEnabled="True"
ItemClick="ItemView_ItemClick">
<GridView.ItemTemplate>
<DataTemplate>
<Grid HorizontalAlignment="Left" Width="250" Height="250">
<Border Background="{ThemeResource ListViewItemPlaceholderBackgroundThemeBrush}">
<Image Source="{Binding ImagePath}" Stretch="UniformToFill" AutomationProperties.Name="{Binding Title}"/>
</Border>
<StackPanel VerticalAlignment="Bottom" Background="{ThemeResource ListViewItemOverlayBackgroundThemeBrush}">
<TextBlock Text="{Binding Title}" Foreground="{ThemeResource ListViewItemOverlayForegroundThemeBrush}" Style="{StaticResource TitleTextBlockStyle}" Height="60" Margin="15,0,15,0"/>
<TextBlock Text="{Binding Subtitle}" Foreground="{ThemeResource ListViewItemOverlaySecondaryForegroundThemeBrush}" Style="{StaticResource CaptionTextBlockStyle}" TextWrapping="NoWrap" Margin="15,0,15,10"/>
</StackPanel>
</Grid>
</DataTemplate>
</GridView.ItemTemplate>
<GridView.ItemsPanel>
<ItemsPanelTemplate>
<ItemsWrapGrid GroupPadding="0,0,70,0"/>
</ItemsPanelTemplate>
</GridView.ItemsPanel>
<GridView.GroupStyle>
<GroupStyle>
<GroupStyle.HeaderTemplate>
<DataTemplate>
<Grid Margin="0,0,0,2">
<Button Foreground="{ThemeResource ApplicationHeaderForegroundThemeBrush}"
AutomationProperties.Name="Group Title"
Click="Header_Click"
Style="{StaticResource TextBlockButtonStyle}" >
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Title}" Margin="0,-11,10,10" Style="{StaticResource SubheaderTextBlockStyle}" TextWrapping="NoWrap" />
<TextBlock Text="{StaticResource ChevronGlyph}" FontFamily="Segoe UI Symbol" Margin="0,-11,0,10" Style="{StaticResource SubheaderTextBlockStyle}" TextWrapping="NoWrap" />
</StackPanel>
</Button>
</Grid>
</DataTemplate>
</GroupStyle.HeaderTemplate>
</GroupStyle>
</GridView.GroupStyle>
</GridView>
<!-- Back button and page title -->
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="120"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Button x:Name="backButton" Margin="39,59,39,0" Command="{Binding NavigationHelper.GoBackCommand, ElementName=pageRoot}"
Style="{StaticResource NavigationBackButtonNormalStyle}"
VerticalAlignment="Top"
AutomationProperties.Name="Back"
AutomationProperties.AutomationId="BackButton"
AutomationProperties.ItemType="Navigation Button"/>
<TextBlock x:Name="pageTitle" Text="{StaticResource AppName}" Style="{StaticResource HeaderTextBlockStyle}" Grid.Column="1"
IsHitTestVisible="false" TextWrapping="NoWrap" VerticalAlignment="Bottom" Margin="0,0,30,40"/>
</Grid>
</Grid>
GroupItemsPage.xaml.cs
namespace AppError
{
public sealed partial class GroupedItemsPage : Page
{
private NavigationHelper navigationHelper;
private ObservableDictionary defaultViewModel = new ObservableDictionary();
public NavigationHelper NavigationHelper
{
get { return this.navigationHelper; }
}
public ObservableDictionary DefaultViewModel
{
get { return this.defaultViewModel; }
}
public GroupedItemsPage()
{
this.InitializeComponent();
this.navigationHelper = new NavigationHelper(this);
this.navigationHelper.LoadState += navigationHelper_LoadState;
}
private async void navigationHelper_LoadState(object sender, LoadStateEventArgs e)
{
// TODO: Create an appropriate data model for your problem domain to replace the sample data
var sampleDataGroups = await SampleDataSource.GetGroupsAsync();
this.DefaultViewModel["Groups"] = sampleDataGroups;
}
void Header_Click(object sender, RoutedEventArgs e)
{
// Determine what group the Button instance represents
var group = (sender as FrameworkElement).DataContext;
// Navigate to the appropriate destination page, configuring the new page
// by passing required information as a navigation parameter
this.Frame.Navigate(typeof(GroupDetailPage), ((SampleDataGroup)group).UniqueId);
}
void ItemView_ItemClick(object sender, ItemClickEventArgs e)
{
// Navigate to the appropriate destination page, configuring the new page
// by passing required information as a navigation parameter
var itemId = ((SampleDataItem)e.ClickedItem).UniqueId;
this.Frame.Navigate(typeof(ItemDetailPage), itemId);
}
}
GroupDetailpage.xaml
<Page
x:Name="pageRoot"
x:Class="AppError.GroupDetailPage"
DataContext="{Binding DefaultViewModel, RelativeSource={RelativeSource Self}}"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:AppError"
xmlns:data="using:AppError.Data"
xmlns:common="using:AppError.Common"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d">
<Page.Resources>
<!-- Collection of items displayed by this page -->
<CollectionViewSource
x:Name="itemsViewSource"
Source="{Binding Items}"
d:Source="{Binding Groups[0].Items, Source={d:DesignData Source=/DataModel/SampleData.json, Type=data:SampleDataSource}}"/>
</Page.Resources>
<!--
This grid acts as a root panel for the page that defines two rows:
* Row 0 contains the back button and page title
* Row 1 contains the rest of the page layout
-->
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}"
DataContext="{Binding Group}"
d:DataContext="{Binding Groups[0], Source={d:DesignData Source=/DataModel/SampleData.json, Type=data:SampleDataSource}}">
<Grid.ChildrenTransitions>
<TransitionCollection>
<EntranceThemeTransition/>
</TransitionCollection>
</Grid.ChildrenTransitions>
<Grid.RowDefinitions>
<RowDefinition Height="140"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<!-- Horizontal scrolling grid -->
<GridView
x:Name="itemGridView"
AutomationProperties.AutomationId="ItemGridView"
AutomationProperties.Name="Items In Group"
TabIndex="1"
Grid.RowSpan="2"
Padding="120,126,120,50"
ItemsSource="{Binding Source={StaticResource itemsViewSource}}"
SelectionMode="None"
IsSwipeEnabled="false"
IsItemClickEnabled="True"
ItemClick="ItemView_ItemClick">
<GridView.ItemTemplate>
<DataTemplate>
<Grid Height="110" Width="480" Margin="10">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Border Background="{ThemeResource ListViewItemPlaceholderBackgroundThemeBrush}" Width="110" Height="110">
<Image Source="{Binding ImagePath}" Stretch="UniformToFill" AutomationProperties.Name="{Binding Title}"/>
</Border>
<StackPanel Grid.Column="1" VerticalAlignment="Top" Margin="10,0,0,0">
<TextBlock Text="{Binding Title}" Style="{StaticResource TitleTextBlockStyle}" TextWrapping="NoWrap"/>
<TextBlock Text="{Binding Subtitle}" Style="{StaticResource CaptionTextBlockStyle}" TextWrapping="NoWrap"/>
<TextBlock Text="{Binding Description}" Style="{StaticResource BodyTextBlockStyle}" MaxHeight="60"/>
</StackPanel>
</Grid>
</DataTemplate>
</GridView.ItemTemplate>
<GridView.Header>
<StackPanel Width="480" Margin="0,4,14,0">
<TextBlock Text="{Binding Subtitle}" Margin="0,0,0,20" Style="{StaticResource SubheaderTextBlockStyle}" MaxHeight="60"/>
<Image Source="{Binding ImagePath}" Height="400" Margin="0,0,0,20" Stretch="UniformToFill" AutomationProperties.Name="{Binding Title}"/>
<TextBlock Text="{Binding Description}" Margin="0,0,0,0" Style="{StaticResource BodyTextBlockStyle}"/>
</StackPanel>
</GridView.Header>
<GridView.ItemContainerStyle>
<Style TargetType="FrameworkElement">
<Setter Property="Margin" Value="52,0,0,2"/>
</Style>
</GridView.ItemContainerStyle>
</GridView>
<!-- Back button and page title -->
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="120"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Button x:Name="backButton" Margin="39,59,39,0" Command="{Binding NavigationHelper.GoBackCommand, ElementName=pageRoot}"
Style="{StaticResource NavigationBackButtonNormalStyle}"
VerticalAlignment="Top"
AutomationProperties.Name="Back"
AutomationProperties.AutomationId="BackButton"
AutomationProperties.ItemType="Navigation Button"/>
<TextBlock x:Name="pageTitle" Text="{Binding Title}" Style="{StaticResource HeaderTextBlockStyle}" Grid.Column="1"
IsHitTestVisible="false" TextWrapping="NoWrap" VerticalAlignment="Bottom" Margin="0,0,30,40"/>
</Grid>
</Grid>
GroupDetailPage.xaml.cs
namespace AppError
{
public sealed partial class GroupDetailPage : Page
{
private NavigationHelper navigationHelper;
private ObservableDictionary defaultViewModel = new ObservableDictionary();
public NavigationHelper NavigationHelper
{
get { return this.navigationHelper; }
}
public ObservableDictionary DefaultViewModel
{
get { return this.defaultViewModel; }
}
public GroupDetailPage()
{
this.InitializeComponent();
this.navigationHelper = new NavigationHelper(this);
this.navigationHelper.LoadState += navigationHelper_LoadState;
}
private async void navigationHelper_LoadState(object sender, LoadStateEventArgs e)
{
// TODO: Create an appropriate data model for your problem domain to replace the sample data
var group = await SampleDataSource.GetGroupAsync((String)e.NavigationParameter);
this.DefaultViewModel["Group"] = group;
this.DefaultViewModel["Items"] = group.Items;
}
void ItemView_ItemClick(object sender, ItemClickEventArgs e)
{
// Navigate to the appropriate destination page, configuring the new page
// by passing required information as a navigation parameter
var itemId = ((SampleDataItem)e.ClickedItem).UniqueId;
this.Frame.Navigate(typeof(ItemDetailPage), itemId);
}
}
ItemDetailPage.xaml
<Page
x:Name="pageRoot"
x:Class="AppError.ItemDetailPage"
DataContext="{Binding DefaultViewModel, RelativeSource={RelativeSource Self}}"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:AppError"
xmlns:data="using:AppError.Data"
xmlns:common="using:AppError.Common"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d">
<Page.Resources>
<CollectionViewSource
x:Name="itemViewSource"
Source="{Binding Items}"
d:Source="{Binding Groups[0].Items, Source={d:DesignData Source=/DataModel/SampleData.json, Type=data:SampleDataSource}}"/>
</Page.Resources>
<!--
This grid acts as a root panel for the page that defines two rows:
* Row 0 contains the back button and page title
* Row 1 contains the rest of the page layout
-->
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}"
DataContext="{Binding Item}"
d:DataContext="{Binding Groups[0].Items[0], Source={d:DesignData Source=/DataModel/SampleData.json, Type=data:SampleDataSource}}">
<Grid.ChildrenTransitions>
<TransitionCollection>
<EntranceThemeTransition/>
</TransitionCollection>
</Grid.ChildrenTransitions>
<Grid.RowDefinitions>
<RowDefinition Height="140"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<!--
TODO: Content should be placed within the following grid
to show details for the current item
-->
<FlipView
Grid.Row="1"
x:Name="flipView"
Margin="50,0,0,0"
ItemsSource="{Binding Source={StaticResource itemViewSource}}">
<FlipView.ItemTemplate>
<DataTemplate>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="500"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<StackPanel>
<Border>
<Image Source="{Binding ImagePath}"/>
</Border>
<TextBlock Text="{Binding Description}" Padding="0,30,0,0" TextWrapping="Wrap"/>
</StackPanel>
<Grid Grid.Column="1" Margin="30,0,0,0">
<TextBlock Text="{Binding Content}" TextWrapping="Wrap"/>
</Grid>
</Grid>
</DataTemplate>
</FlipView.ItemTemplate>
</FlipView>
<!-- Back button and page title -->
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="120"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Button x:Name="backButton" Margin="39,59,39,0" Command="{Binding NavigationHelper.GoBackCommand, ElementName=pageRoot}"
Style="{StaticResource NavigationBackButtonNormalStyle}"
VerticalAlignment="Top"
AutomationProperties.Name="Back"
AutomationProperties.AutomationId="BackButton"
AutomationProperties.ItemType="Navigation Button"/>
<TextBlock x:Name="pageTitle" Text="{Binding Title}" Style="{StaticResource HeaderTextBlockStyle}" Grid.Column="1"
IsHitTestVisible="false" TextWrapping="NoWrap" VerticalAlignment="Bottom" Margin="0,0,30,40"/>
</Grid>
</Grid>
ItemDetailPage.xaml.cs
namespace AppError
{
public sealed partial class ItemDetailPage : Page
{
private NavigationHelper navigationHelper;
private ObservableDictionary defaultViewModel = new ObservableDictionary();
public NavigationHelper NavigationHelper
{
get { return this.navigationHelper; }
}
public ObservableDictionary DefaultViewModel
{
get { return this.defaultViewModel; }
}
public ItemDetailPage()
{
this.InitializeComponent();
this.navigationHelper = new NavigationHelper(this);
this.navigationHelper.LoadState += navigationHelper_LoadState;
}
private async void navigationHelper_LoadState(object sender, LoadStateEventArgs e)
{
// TODO: Create an appropriate data model for your problem domain to replace the sample data
var group = await SampleDataSource.GetGroupAsync((String)e.NavigationParameter);
var item = await SampleDataSource.GetItemAsync((String)e.NavigationParameter);
this.DefaultViewModel["Group"] = group;
this.DefaultViewModel["Items"] = group.Items;
this.flipView.SelectedItem = item;
}
}

WPF Xaml - match width

I have the following xaml, where you can see a GroupBox on top and other ones on the left and on the right.
Is there a way to set the GroupBox on top so that (when I resize the window) its left and right edges are aligned respectively with the left edge of the GroupBoxes on the left and the right edge of the GroupBoxes on the right?
Edit
I'm keeping fixed the width of the groupboxes in the tab controls because I've implemented a wpf zooming there: I've updated the xaml now (of course the zoom is implemented also in the code behind)
<?xml version="1.0" encoding="utf-8"?>
<Window
x:Class="MatchWidth.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MatchWidth"
Height="1000"
Width="1600">
<Grid>
<Grid.RowDefinitions>
<RowDefinition
Height="100" />
<RowDefinition
Height="*" />
</Grid.RowDefinitions>
<GroupBox
Header="Top Box"
Grid.Row="0"
HorizontalAlignment="Stretch"
VerticalAlignment="Stretch"
Margin="25,5,35,25" />
<Grid
Grid.Row="1">
<Grid.LayoutTransform>
<ScaleTransform
CenterX="0" CenterY="0"
ScaleX="{Binding ElementName=uiScaleSliderL,Path=Value}"
ScaleY="{Binding ElementName=uiScaleSliderL,Path=Value}"/>
</Grid.LayoutTransform>
<Grid.ColumnDefinitions>
<ColumnDefinition
Width="*" />
<ColumnDefinition
Width="5" />
<ColumnDefinition
Width="*" />
</Grid.ColumnDefinitions>
<TabControl
Name="LeftTabCtr"
Grid.Column="0">
<TabItem Header="LeftTabCtr">
<ScrollViewer
HorizontalScrollBarVisibility="Auto">
<Grid
Height="800">
<Slider
x:Name="uiScaleSliderL"
ToolTip="Determines the UI scale factor."
Value="1" Minimum="0.1" Maximum="4" Width="200" Height="10"
HorizontalAlignment="Center" VerticalAlignment="Top" />
<GroupBox
Header="Left Box 1"
Grid.Column="0"
Grid.Row="0"
HorizontalAlignment="Stretch"
VerticalAlignment="Top"
Margin="25,20,25,25"
Width="720"
Height="180"/>
<GroupBox
Header="Left Box 2"
Grid.Column="0"
Grid.Row="0"
HorizontalAlignment="Stretch"
VerticalAlignment="Stretch"
Width="720"
Margin="25,220,25,10" />
</Grid>
</ScrollViewer>
</TabItem>
</TabControl>
<GridSplitter
Grid.Column="1"
Width="5"
HorizontalAlignment="Stretch" />
<TabControl
Name="RightTabCtr"
Grid.Column="2">
<TabItem Header="RightTabCtr">
<ScrollViewer
HorizontalScrollBarVisibility="Auto">
<Grid
Height="800"> <Slider
x:Name="uiScaleSliderR"
ToolTip="Determines the UI scale factor."
Value="1" Minimum="0.1" Maximum="4" Width="200" Height="10"
HorizontalAlignment="Center" VerticalAlignment="Top" />
<GroupBox
Header="Right Box 1"
Grid.Column="0"
Grid.Row="0"
HorizontalAlignment="Stretch"
VerticalAlignment="Top"
Margin="25,20,25,25"
Width="720"
Height="180"/>
<GroupBox
Header="Right Box 2"
Grid.Column="0"
Grid.Row="0"
HorizontalAlignment="Stretch"
VerticalAlignment="Stretch"
Width="720"
Margin="25,220,25,10" />
</Grid>
</ScrollViewer>
</TabItem>
</TabControl>
</Grid>
</Grid>
</Window>
The code behind contains something like that:
public partial class Window1 : Window
{
public Window1()
{
InitializeComponent();
uiScaleSliderL.MouseDoubleClick +=
new MouseButtonEventHandler(RestoreScalingFactorL);
}
protected override void OnPreviewMouseWheel(MouseWheelEventArgs args)
{
base.OnPreviewMouseWheel(args);
if (Keyboard.IsKeyDown(Key.LeftCtrl) ||
Keyboard.IsKeyDown(Key.RightCtrl))
{
uiScaleSliderL.Value += (args.Delta > 0) ? 0.1 : -0.1;
}
}
protected override void OnPreviewMouseDown(MouseButtonEventArgs args)
{
base.OnPreviewMouseDown(args);
if (Keyboard.IsKeyDown(Key.LeftCtrl) ||
Keyboard.IsKeyDown(Key.RightCtrl))
{
if (args.MiddleButton == MouseButtonState.Pressed)
{
RestoreScalingFactorL(uiScaleSliderL, args);
}
}
}
void RestoreScalingFactorL(object sender, MouseButtonEventArgs args)
{
((Slider)sender).Value = 1.0;
}
}

You must specify correct margins and remove constant widths of groupboxes (maybe in your case it will be more flexibile to use minWidth, or just remove it completely)

C# WPF - TransitioningContentControl with App.content

I Work with the theme of MahApps (Metro Dark) I looked the animations of this theme.
I came to a dead end: indeed I created a system to switch between different UserControl, that is to say that I have only one window and clicking on different buttons, I have this or such UserControl. But now I am with this system switch, I have no animation (only the start of the application).
How can I make an animation for each change in UserControl (Keeping Metro theme)?
Somebody ask me : use TransitioningContentControl
But i made my switcher like this :
class Switcher
{
public static UserControl WClient;
public static UserControl WHome;
public static UserControl WDataBase;
public Switcher()
{
WClient = new Windows.Client();
WHome = new Windows.Home();
WDataBase = new Windows.DataBase();
}
public static void currentWindow(UserControl window, string color)
{
Window curApp = Application.Current.MainWindow;
curApp.Content = window;
if (window == WClient)
{
curApp.Title = "CLIENT - INFO-TOOLS - BY NAOGRAFIX";
}
else if (window == WDataBase)
{
curApp.Title = "DATABASE - INFO-TOOLS - BY NAOGRAFIX";
}
else
{
curApp.Title = "HOME - INFO-TOOLS - BY NAOGRAFIX";
}
currentColor(color);
}
}
Now, when i clic on a button (to switch userControl) i use this :
private void BtnDataBase_Click(object sender, RoutedEventArgs e)
{
var color = "Red";
if (DataBase.isConnected) { color = "Green"; }
Switcher.currentWindow(Switcher.WDataBase, color);
}
I use CONTENT, i dont know if i can use TransitioningContentControl
Help :)
Nao*

You do need to use transitioning content control as you have said. You can add that as the direct content of the window then access it by name from the mainwindow and change its content instead.
Xaml
<metro:TransitioningContentControl x:Name="tContent"/>
C#
((ContentControl)curApp.FindName("tContent")).Content = window;
You will need the xml namespace definition
xmlns:metro="clr-namespace:MahApps.Metro.Controls;assembly=MahApps.Metro"
and you can change the transition using the Transition property on TransitioningContentControl

WPF XAML below shows use of MahApps.Metro TransitioningContentControl.
Click on the Content listbox to switch content.
Select the transition effect in the Transition listbox, then change selected Content to see the effect.
<Window x:Class="WpfMahApp.MainWindow"
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:mah="http://metro.mahapps.com/winfx/xaml/controls"
mc:Ignorable="d"
Title="MainWindow" Height="600" Width="800">
<Window.Resources>
<TextBlock x:Key="Content1" Width="400" Height="200" Text="Content 1: TextBox" Background="Aqua" />
<Canvas x:Key="Content2" Width="200" Height="400" Background="DarkOrange">
<Ellipse Fill="YellowGreen" Stroke="Black" Width="100" Height="200" />
<Label Content="Content2: Canvas" />
</Canvas>
<Border x:Key="Content3" Width="100" Height="100" Background="Yellow" BorderBrush="Blue" BorderThickness="2" CornerRadius="4">
<TextBlock Text="Content3: Border" />
</Border>
</Window.Resources>
<StackPanel Orientation="Horizontal">
<StackPanel Orientation="Vertical" >
<CheckBox Margin="4" Content="Is Transitioning" IsChecked="{Binding ElementName=TransitioningContentControl,Path=IsTransitioning , Mode=OneWay}" />
<StackPanel Orientation="Vertical" Margin="8">
<TextBlock Text="Content" FontWeight="Bold"/>
<ListBox Name="ContentSelection" HorizontalAlignment="Left">
<ListBoxItem Content="Content 1" Tag="{StaticResource Content1}" />
<ListBoxItem Content="Content 2" Tag="{StaticResource Content2}" />
<ListBoxItem Content="Content 3" Tag="{StaticResource Content3}" />
</ListBox>
</StackPanel>
<StackPanel Orientation="Vertical" Margin="8">
<TextBlock Text="Transition" FontWeight="Bold" />
<ListBox Name="Transition" HorizontalAlignment="Left">
<ListBoxItem Content="Default" Tag="{x:Static mah:TransitionType.Default}"/>
<ListBoxItem Content="Normal" Tag="{x:Static mah:TransitionType.Normal}"/>
<ListBoxItem Content="Up" Tag="{x:Static mah:TransitionType.Up}"/>
<ListBoxItem Content="Down" Tag="{x:Static mah:TransitionType.Down}"/>
<ListBoxItem Content="Left" Tag="{x:Static mah:TransitionType.Left}" />
<ListBoxItem Content="Right" Tag="{x:Static mah:TransitionType.Right}"/>
<ListBoxItem Content="LeftReplace" Tag="{x:Static mah:TransitionType.LeftReplace}"/>
<ListBoxItem Content="RightReplace" Tag="{x:Static mah:TransitionType.RightReplace}"/>
</ListBox>
</StackPanel>
</StackPanel>
<mah:TransitioningContentControl Margin="8"
Name="TransitioningContentControl"
Background="Beige" BorderBrush="Black" BorderThickness="1"
Content="{Binding ElementName=ContentSelection, Path=SelectedValue.Tag}"
Transition="{Binding ElementName=Transition, Path=SelectedValue.Tag}" />
</StackPanel>
</Window>

Dynamically adding contents to stackpanel in code behind

Am trying to add Set of labels and images in a stackpanel in code behind.And finally am attaching that stackpanel to particular column of a grid control.My expected output should be like
<image><label>
combination
but my output is like it displays the label in first column of grid and the image in the next column.(I was not able to add the snapshots since i dont have enough reputations)
XAML code
<Window x:Class="Ping.MainWindow" WindowStyle="ThreeDBorderWindow" Icon="F:\ChatApplication\Ping\Ping\Images\title.ico" Cursor="Pen"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Ping - Connected by alphabets" Height="450" Width="750" WindowStartupLocation="CenterScreen" SizeToContent="WidthAndHeight" >
<Grid Name="grid_window">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="200"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<GridSplitter HorizontalAlignment="Right"
VerticalAlignment="Stretch"
Grid.Column="1" ResizeBehavior="PreviousAndNext"
Width="5" Background="#FFBCBCBC"/>
<TabControl Grid.ColumnSpan="2" Name="tab_control" BorderBrush="Cornsilk" BorderThickness="4" HorizontalAlignment="Left" Height="419" Margin="227,0,0,0" VerticalAlignment="Top" Width="515">
<TabItem Header="Home" BorderBrush="Green"/>
</TabControl>
</Grid>
code behind
public MainWindow()
{
InitializeComponent();
DBCoding dbobj = new DBCoding();
//Contains names {"Dhivi","Walle"}
List<string> online = new List<string>();
online = dbobj.onlineUsers();
StackPanel myStackPanel = new StackPanel();
myStackPanel.Orientation = Orientation.Vertical;
foreach (var item in online)
{
Image myImage = new Image();
myImage.Source = new BitmapImage(new Uri("F:\\ChatApplication\\Ping\\Ping\\Images\\visible.png"));
myImage.Width = 10;
myImage.Height = 10;
//myImage.Margin = new Thickness(-10,0,-80,0);
myImage.Height = 10;
Label user = new Label();
user.Content = item.ToString();
myStackPanel.Children.Add(myImage);
myStackPanel.Children.Add(user);
}
grid_window.Children.Add(myStackPanel);
Grid.SetColumnSpan(myStackPanel, 1);
Grid.SetColumn(myStackPanel, 0);
}
Can anybody tell me the solution.

Here's how your code should look like, using data binding, an ItemsControl and a DataTemplate:
XAML
<Window x:Class="Ping.MainWindow" WindowStyle="ThreeDBorderWindow" Icon="F:\ChatApplication\Ping\Ping\Images\title.ico" Cursor="Pen"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Ping - Connected by alphabets" Height="450" Width="750" WindowStartupLocation="CenterScreen" SizeToContent="WidthAndHeight" >
<Grid Name="grid_window">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="200"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<GridSplitter HorizontalAlignment="Right"
VerticalAlignment="Stretch"
Grid.Column="1" ResizeBehavior="PreviousAndNext"
Width="5" Background="#FFBCBCBC"/>
<TabControl Grid.ColumnSpan="2" Name="tab_control" BorderBrush="Cornsilk" BorderThickness="4" HorizontalAlignment="Left" Height="419" Margin="227,0,0,0" VerticalAlignment="Top" Width="515">
<TabItem Header="Home" BorderBrush="Green"/>
</TabControl>
<ItemsControl ItemsSource="{Binding}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<DockPanel>
<!-- You really should add the image as a resource to the project -->
<Image Source="F:\ChatApplication\Ping\Ping\Images\visible.png"
Width="10" Height="10" />
<TextBlock Text="{Binding}" />
</DockPanel>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Grid>
C#
public MainWindow()
{
InitializeComponent();
DBCoding dbobj = new DBCoding();
List<string> online = dbobj.onlineUsers();
DataContext = online;
}