I have a XAML page in a Windows 8.1 Store App. I set the data context for a ListView but I initially have it collapsed. What I am trying to do is toggle the visibility of some of the elements in the ListView before making it visible. But it doesn't load them unless it becomes visible. So, to forced it to load the items, I am trying to set "IsVirtualizing" to false so that I don't have to worry about it (and I don't mind the hit in performance since I won't have that many items). But for all the examples I look at, all I get is
The property "IsVirtualizing" does not have an accessible setter.
Not sure what is going on here.
Here is the relevant piece of code with the other contents stripped out.
<common:LayoutAwarePage
x:Class="FlashMe.DeckView"
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:FlashMe"
xmlns:common="using:FlashMe.Common"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
>
<ScrollViewer x:Name="deckScrollViewer" Grid.Row="1" VerticalScrollMode="Disabled" HorizontalScrollMode="Enabled" HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Disabled" Margin="0,15,0,0">
<StackPanel x:Name="deckStackPanel" Orientation="Horizontal">
<Grid Width="100" x:Name="MarginBuffer" />
<ListView x:Name="cardsListViewDisplay" Visibility="Collapsed" SelectionMode="None" Width="500" ItemsSource="{Binding Path=FlashCardsAsList}" VirtualizingStackPanel.IsVirtualizing="False">
<ListView.ItemTemplate>
<DataTemplate>
<Border>
<StackPanel Orientation="Vertical" Width="490" Height="400" RightTapped="FlashCardRightClicked">
<Grid Width="490" Height="200" Background="Gainsboro">
<TextBlock Text="{Binding Path=Front}"
Foreground="Black"
Style="{StaticResource GroupHeaderTextStyle}"
Margin="4,0,4,4"
FontWeight="SemiBold"
VerticalAlignment="Center"
HorizontalAlignment="Center"
TextWrapping="Wrap"
MaxWidth="410"/>
</Grid>
<Grid Width="500" Height="200" Background="{Binding ElementName=deckStackPanel, Path=DataContext.DeckColorBrush}">
<TextBlock Text="{Binding Path=Back}"
Foreground="White"
Style="{StaticResource GroupHeaderTextStyle}"
Margin="4,0,0,4"
FontWeight="SemiBold"
VerticalAlignment="Center"
HorizontalAlignment="Center"
TextWrapping="Wrap"
MaxWidth="410"/>
</Grid>
</StackPanel>
</Border>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackPanel>
</ScrollViewer>
</common:LayoutAwarePage>
In Windows Store Apps, the IsVirtualizing property is read-only.
From the Remarks section on the VirtualizingStackPanel.IsVirtualizingProperty page on MSDN:
VirtualizingStackPanel.IsVirtualizing is an atypical attached property
because it does not have a Set accessor, and thus is not really a XAML
attached property with a markup usage. Instead,
VirtualizingStackPanel.IsVirtualizing functions as a sentinel whereby
child elements can query the VirtualizingStackPanel parent, and
determine whether virtualization is being used. ...
Related
I'm building a UWP in C# with Visual Studio, and need to hide and show a NavigationView, named 'navigationView' as required.
I am using the property .IsPaneVisible to achieve this, but am encountering a strange bug:
I can set IsPaneVisible = true or false in the xaml document, but if I set navigationView.IsPaneVisible = false; in the related C# document, and run a debug build of the app from Visual Studio, the app crashes with the error
System.ArgumentException: 'The parameter is incorrect.
Even stranger, if I run the same debug build, but launched directly, outside Visual Studio, the app functions normally without crashing at this line.
Does anyone have an idea of why this might be happening or how I could fix it?
Here's the xaml code:
<Page
x:Class="Sheet_Music_Reader.Views.ShellPage"
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:i="using:Microsoft.Xaml.Interactivity"
xmlns:behaviors="using:Sheet_Music_Reader.Behaviors"
xmlns:winui="using:Microsoft.UI.Xaml.Controls"
xmlns:helpers="using:Sheet_Music_Reader.Helpers"
xmlns:views="using:Sheet_Music_Reader.Views"
Loaded="OnLoaded"
mc:Ignorable="d">
<Page.Resources>
<!--This top margin is the height of the custom TitleBar-->
<Thickness x:Key="NavigationViewContentMargin">0,48,0,0</Thickness>
<Thickness x:Key="NavigationViewContentGridBorderThickness">0</Thickness>
<SolidColorBrush x:Key="NavigationViewContentBackground" Color="Transparent"></SolidColorBrush>
</Page.Resources>
<Grid>
<Border x:Name="AppTitleBar"
IsHitTestVisible="True"
VerticalAlignment="Top"
Background="Transparent"
Height="40"
Canvas.ZIndex="1"
Margin="48,8,0,0">
<StackPanel Orientation="Horizontal">
<Image x:Name="AppFontIcon"
HorizontalAlignment="Left"
VerticalAlignment="Center"
Source="Assets/Square44x44Logo.png"
Width="16"
Height="16"/>
<TextBlock x:Name="AppTitle"
Text="enScore"
VerticalAlignment="Center"
Margin="12,0,0,0"
Style="{ThemeResource CaptionTextBlockStyle}"/>
</StackPanel>
</Border>
<winui:NavigationView
IsBackButtonVisible="Visible"
IsBackEnabled="{x:Bind IsBackEnabled, Mode=OneWay}"
SelectedItem="{x:Bind Selected, Mode=OneWay}"
ItemInvoked="OnItemInvoked"
IsSettingsVisible="True"
IsTitleBarAutoPaddingEnabled="False"
DisplayModeChanged="NavigationViewControl_DisplayModeChanged"
Canvas.ZIndex="0"
x:Name="navigationView">
<winui:NavigationView.MenuItems>
<winui:NavigationViewItem x:Uid="Shell_Main" Icon="Copy" helpers:NavHelper.NavigateTo="views:MainPage" />
</winui:NavigationView.MenuItems>
<i:Interaction.Behaviors>
<behaviors:NavigationViewHeaderBehavior
DefaultHeader="{x:Bind Selected.Content, Mode=OneWay}">
<behaviors:NavigationViewHeaderBehavior.DefaultHeaderTemplate>
<DataTemplate>
<Grid x:Name="headerGrid">
<TextBlock
Text="{Binding}"
Style="{ThemeResource TitleTextBlockStyle}"
Margin="{StaticResource SmallLeftRightMargin}" />
<Button Style="{ThemeResource ButtonRevealStyle}" Content="Refresh Library Contents" HorizontalAlignment="Right" Margin="0,45,8,0" Click="RefreshLibrary"/>
<Button Style="{ThemeResource ButtonRevealStyle}" Content="Import PDF To Current Folder" HorizontalAlignment="Right" Margin="0,-35,140,0" Click="AddScore"/>
<Button Style="{ThemeResource ButtonRevealStyle}" Content="Add New Folder" HorizontalAlignment="Right" Margin="0,-35,8,0" Click="AddFolderAsync"/>
<ToggleButton Style="{ThemeResource ToggleButtonRevealStyle}" x:FieldModifier="public" x:Name="tbtndelete" Content="Delete Items" HorizontalAlignment="Right" Margin="0,45,191,0" Tapped="DeleteItem"/>
</Grid>
</DataTemplate>
</behaviors:NavigationViewHeaderBehavior.DefaultHeaderTemplate>
</behaviors:NavigationViewHeaderBehavior>
</i:Interaction.Behaviors>
<Grid>
<Frame x:Name="shellFrame" />
</Grid>
</winui:NavigationView>
</Grid>
</Page>
Try to change the placement of the menu with:
PaneDisplayMode="Top"
For my case with Microsoft.UI.Xaml.Controls for Microsoft.WindowsAppSDK v1.0.0.
the showing/hidding of menu bar works fine.
Left, LeftMinimal, LeftCompact crashes the app.
I know you may expect the menu on the left, but still on the top is not that bad idea ;-) At least it works.. Greetz.
I have a simple Border and Grid that is positioned within a Canvas container in WPF. The position of the control changes during runtime hence why it resides in the canvas.
The XAML for the control looks something like this:
<Border Name="PopupArea"
Width="130"
Height="150"
BorderBrush="Black"
BorderThickness="2"
CornerRadius="5">
<Border.Background>
<SolidColorBrush Opacity="0.5" Color="Black" />
</Border.Background>
<Grid>
<StackPanel>
<Border HorizontalAlignment="Center">
<Border.Effect>
<DropShadowEffect />
</Border.Effect>
<TextBlock FontWeight="Bold" Style="{StaticResource SmallWhiteFont}">HELLO WORLD</TextBlock>
</Border>
</StackPanel>
</Grid>
</Border>
However I now need to be able to create a Collection of the above control which I create and destory as required at runtime in code.
My questions are :
A. What is the best way to compose my XAML to create multiple instances of the above control through code? Do I just declare a ContentControl in the resources?
B. Assuming I am correct and a resource template is required. How do I actually use it to create multiple instances of the control in code?
Within XAML I would use an ItemTemplate.
Then I would bind ItemsSource to some observable collection on my viewmodel.
Here's an example taken from MSDN:
<ListBox Width="400" Margin="10"
ItemsSource="{Binding Source={StaticResource myTodoList}}">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel>
<TextBlock Text="{Binding Path=TaskName}" />
<TextBlock Text="{Binding Path=Description}"/>
<TextBlock Text="{Binding Path=Priority}"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
NOTE:
It is more common to define a DataTemplate in the resources section so it can be a reusable object.
<ListBox Width="400" Margin="10"
ItemsSource="{Binding Source={StaticResource myTodoList}}"
ItemTemplate="{StaticResource myTaskTemplate}"/>
i do have a problem with binding the visibility of my usercontrol.
The binding to a Dependency Property of type Visibility works fine and the correct value (in this case Collapsed) is held by the DP. The content of my Grid within the UserControl is set to collapsed, but the hole control doesnt collapse. It still keeps the space occupied defined by with and heigth, as referenced in the xaml.
EDIT: i found out, that the problem is that i set width and height in the xaml where i reference my usercontrol. if i don't do this, the control collapses correct (therefore binding works fine). But i need to set width and heigth in case the usercontrol is visible.
Any idea how i can solve this problem?
<my:MenuButtonBase x:Class="bxSuite.Controls.MenuButtonLarge"
xmlns:my="clr-namespace:bxSuite.Controls"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
Background="Black"
>
<Grid Visibility="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type UserControl}}, Path=ButtonVisibility}" >
<StackPanel>
<Image Source="{Binding ButtonImageSource}" Margin="5,10,5,5" Width="48" Height="48" VerticalAlignment="Top" HorizontalAlignment="Center" />
<TextBlock Text="{Binding FunctionHeader}" Foreground="White" TextWrapping="Wrap" TextAlignment="Center" Padding="5,5,5,5" FontSize="12" />
</StackPanel>
</Grid>
</my:MenuButtonBase>
In XAML i reference my usercontrol like this (where the Converter produces the visibility-state correctly):
<my:MenuButtonLarge Name="btnInEuqipment" ButtonVisibility="{Binding Path=User, Converter={StaticResource ConverterUserRightVisibility}, ConverterParameter=5}" VerticalAlignment="Top" FunctionHeader="{lex:Loc Key=MenuButton_InEquipment}" Width="130" ButtonImageSource="/bxSuite.RolloutManager;component/Images/inequipment_48x48.png" BackgroundEnabled="#FF0694FD" BackgroundHover="#FF0072C6" MenuButtonClick="btnInEuqipment_MenuButtonClick" Height="95" Margin="5,10,0,0" />
Try set the visibility of the user control instead of the grid, should work.
Your code should be like this.
<my:MenuButtonBase x:Class="bxSuite.Controls.MenuButtonLarge"
xmlns:my="clr-namespace:bxSuite.Controls"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
Visibility="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type UserControl}}, Path=ButtonVisibility}"
Background="Black">
<Grid>
<StackPanel>
<Image Source="{Binding ButtonImageSource}"
Margin="5,10,5,5"
Width="48"
Height="48"
VerticalAlignment="Top"
HorizontalAlignment="Center" />
<TextBlock Text="{Binding FunctionHeader}"
Foreground="White"
TextWrapping="Wrap"
TextAlignment="Center"
Padding="5,5,5,5"
FontSize="12" />
</StackPanel>
</Grid>
Dont forget to update the RelativeSource of your bind.
I have a custom control which contains one text-block, one combo-box and one hyper-link button.
<UserControl x:Class="IXExpress.Controls.WorkspaceIndexes"
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:telerikSdk="http://schemas.telerik.com/2008/xaml/presentation"
mc:Ignorable="d"
Height="Auto" Width="Auto">
<Grid x:Name="LayoutRoot">
<StackPanel Orientation="Vertical" HorizontalAlignment="Center">
<TextBlock x:Name="IndexNameTextBlock" Text="{Binding ApplicationStrings.SelectIndexName, Source={StaticResource ResourceWrapper}, Mode=OneTime}" Margin="3,5" TextAlignment="Left" VerticalAlignment="Center" Visibility="Visible"/>
<StackPanel Orientation="Horizontal" HorizontalAlignment="Left">
<telerikSdk:RadComboBox x:Name="IndexNameCB"
DisplayMemberPath="IndexName"
HorizontalAlignment="Center"
IsDropDownOpen="False"
Margin="3,0,3,5"
MinWidth="150"
Width="150"
VerticalAlignment="Center"
VerticalContentAlignment="Center"
Visibility="Visible"
SelectionChanged="IndexNameCB_SelectionChanged"/>
<HyperlinkButton x:Name="CreateNewIndexLink"
Content="Create New"
VerticalContentAlignment="Center"
Click="CreateNewIndexLink_Click"/>
</StackPanel>
</StackPanel>
</Grid>
</UserControl>
I am using it on another page as following:
<StackPanel Orientation="Vertical">
<customControls:WorkspaceIndexes x:Name="WorkspaceIndexes" IsMoreTextRequired="True" Margin="3"/>
</StackPanel>
The issue is, on some condition when I want to disable this control but it only disables combo-box and hyper-link button.
code:
if (my condition)
WorkspaceIndexes.IsEnabled = true;
else
WorkspaceIndexes.IsEnabled = false;
Result:
http://imgur.com/L6tbOwo
I also don't see IsEnabled option for "IndexNameTextBlock" text-block, Why is that?
You can't see the IsEnabled property for the TextBlock because it doesn't have the property. The other Elements are derived from Control, they can be enabled and disabled. The TextBlock is no Control. Disabling a TextBlock would be meaningless. It just displays text. No user interaction possible.
If you need it to be grayed out you have to change either its Foreground color, or reduce its Opacity, or place a semi-transparent Rectangle/Border over it.
I wanna create a infinite longlistselector, but my event ItemRealized does not fire. i have create view model so i can generate an observable collection, and everything sees to be working fine when i monitoring the main class, i'm sure that it is not empty, but my problem is that i can not populate the longlistselector
<phone:PhoneApplicationPage.Resources>
<vm:GoogleView x:Key="viewModel"/>
</phone:PhoneApplicationPage.Resources>
longlistselector
<phone:LongListSelector ItemRealized="m_ListBoxGoogle_ItemRealized" Name="m_ListGoogle" HorizontalAlignment="Center" Height="410" Margin="0,120,0,0"
ItemsSource="{Binding GoogleCollection}"
DataContext="{StaticResource viewModel}">
<phone:LongListSelector.ItemTemplate>
<DataTemplate>
<Button Tag="{Binding GoogleID}" Style="{StaticResource NoVisualTextButton }" toolkit:TiltEffect.IsTiltEnabled="True" Click="OnListBoxItemClick" Margin="-10,0,0,0">
<StackPanel Orientation="Horizontal" Margin="0,3,0,0" Height="auto" Width="450">
<Border BorderThickness="1" Width="62" Height="62" BorderBrush="#00aef0" Background="#00aef0">
<Image Height="60" Width="60" Source="{Binding GoogleImagePath}"/>
</Border>
<StackPanel Width="350" HorizontalAlignment="Center" Margin="12,0,0,0" >
<TextBlock Text="{Binding GoogleDisplayName}" TextWrapping="NoWrap" Style="{StaticResource PanoramaItemTextStyle }" FontSize="24" />
<TextBlock Text="{Binding GoogleObjectType}" TextWrapping="NoWrap" Style="{StaticResource PanoramaItemTextStyle }" FontSize="20" />
</StackPanel>
</StackPanel>
</Button>
</DataTemplate>
</phone:LongListSelector.ItemTemplate>
</phone:LongListSelector>
i'm really stuck guys, please help me
Try these things for I believe its a binding issue:
Debug and put a breakpoint in the GoogleView constructor and verify
it is being instantiated.
If it is being instantiated verify the data you are binding to exists within the class.
If everything instantiated, try binding to the collection as TwoWay binding mode.
If that doesn't work try binding to the data in another control to verify things are working properly.