Trying to set the IsSelected Property for all items to be TRUE on a Multiple Select Mode ListView. I think I have the syntax correct. Any guesses as to what is wrong?
<ListView x:Name="myListView" SelectionMode="Multiple" BorderThickness="1"
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel>
<Image Source="{Binding Thumbnail}"/>
<TextBlock Text="{Binding dataSource.Name}"/>
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
<ListView.ItemContainerStyle>
<Style TargetType="ListViewItem">
<Setter Property="IsSelected" Value="True" />
</Style>
</ListView.ItemContainerStyle>
</ListView>
Turns out this is not possible in WINRT
Workaround found # http://pmichaels.net/2014/09/18/binding-isselected-method-in-the-listview-control-in-winrt/
I have answered in comment for your another question, but still.
Unfortunately, bindings are not supported on Setters in WinRT. I think Silverlight only got them in version 5. For workarounds you basically could define an attached dependency property that sets up the binding for you. You can have a look here: here
Hope this helps!
Related
This has come up a few times, and I've been struggling with it all day in a UWP app.
My specific issue was that I was using x:Bind inside a ContentTemplate that was inside a DataTemplate:
<DataTemplate x:DataType="IFactionMember">
<Button Command="{x:Bind **Property of IFactionMember**}"> // Good
<Button.Template>
<ControlTemplate TargetType="Button">
<Grid Padding="10,0">
<TextBlock Text="{x:Bind **Property of IFactionMember**}" /> // Bad
</Grid>
</ControlTemplate>
</Button.Template>
</Button>
</DataTemplate>
You cannot do this :(
You could use {Binding} instead for your scenario, for example:
<ListView x:Name="listview" ItemsSource="{x:Bind members}">
<ListView.ItemTemplate>
<DataTemplate x:DataType="local:IFactionMember">
<Button >
<Button.Template>
<ControlTemplate TargetType="Button" >
<Grid Padding="10,0">
<TextBlock Text="{Binding testtext}" />
</Grid>
</ControlTemplate>
</Button.Template>
</Button>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
x:bind lacks some of the features of {Binding}, in x:Bind, Path is rooted at the Page by default, not the DataContext, it seems like if you are using x:bind here, it will try to find the property at the MainPage, so that it will not find the correct property.
I have explored ISupportIncrementalLoading and seen MS sample and other examples for infinite scrolling behaviour.
But I want bottom to top scrolling where items are added on top on scrolling bottom to top.
Edit:I have found a workaround for this. I have rotated listview by 180 degree and datatemplate by 180 degree which helped me achieve desired functionality.
<ListView x:Name="GridViewMain" IncrementalLoadingThreshold="2" RenderTransformOrigin="0.5,0.5">
<ListView.RenderTransform>
<RotateTransform Angle="180"></RotateTransform>
</ListView.RenderTransform>
<ListView.ItemContainerStyle>
<Style TargetType="ListViewItem">
<Setter Property="HorizontalContentAlignment" Value="Stretch"/>
<Setter Property="VerticalContentAlignment" Value="Stretch"/>
</Style>
</ListView.ItemContainerStyle>
<ListView.Resources>
<DataTemplate x:Key="DataTemplateGridViewMain">
<Grid HorizontalAlignment="Stretch" Background="#FF7C1A9B" RenderTransformOrigin="0.5,0.5">
<Grid.RenderTransform>
<RotateTransform Angle="180"/>
</Grid.RenderTransform>
<TextBlock HorizontalAlignment="Left" Text="{Binding}" VerticalAlignment="Center" FontSize="20" FontFamily="Tempus Sans ITC" />
</Grid>
</DataTemplate>
</ListView.Resources>
<ListView.ItemTemplate>
<StaticResource ResourceKey="DataTemplateGridViewMain" />
</ListView.ItemTemplate>
</ListView>
Is this solution has any perf impact or is there any alternate way to do this?
not sure if this will fit your needs, but I had to do something similar when creating a chat conversation screen, and was able to achieve this using ExtendedListView: https://www.nuget.org/packages/ExtendedListView
We load the most recent items, and use ScrollIntoView(lastMessage) to position the cursor at the bottom. Normally you would use MoreDataRequested event to get items when it scrolls to the bottom, but instead we reversed it and used the PullToRefreshRequested to simulate scrolling to the top, changing the loading template to say "loading more messages".
works pretty well for us, I hope this is helpful!
Say i have this XAML :
<StackPanel>
<TextBlock Text="{Binding Path=TaskName}" />
<TextBlock Text="{Binding Path=Description}"/>
<TextBlock Text="{Binding Path=Priority}"/>
</StackPanel>
I'd like re use it across multiple places.
For example as a DataTemplate for a ItemsControl but also as The basis for something like a buttons content.
How would i go about doing this?
I'm thinking something like an ASP.NET Partial view.
I don't want to use a usercontrol as i don't require any code behind.
I managed to get it to work in a way using a style:
<Style x:Key="myStyle" TargetType="Control">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate>
<StackPanel>
<TextBlock Text="{Binding Path=TaskName}" />
<TextBlock Text="{Binding Path=Description}"/>
<TextBlock Text="{Binding Path=Priority}"/>
</StackPanel>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
It insisted on me using a TargetType otherwise it complained about setting the template.
I can now use this on any control.
If i want to then use this essentially as a datatemplate, i can just set the style of the placeholder item within the datatemplate (probably a ContentControl) to use this.
Create a StylesResourceDictionary.xaml and create a staticresource in your App.Xaml. At runtime, the styles will get binded and then you can reference anything from the dictionary anywhere in your app, across usercontrols or datatemplates etc.
I have a listbox control added to my layout as show in the below code snippet.
<ListBox x:Name="lstFilters" ItemsSource="{Binding CustomerCollection, Source={StaticResource VMCustomers}}" ScrollViewer.VerticalScrollBarVisibility="Disabled" Height="200" Margin="12,20,235,80">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<HyperlinkButton Content="{Binding Name}" Style="{StaticResource styleFont}"></HyperlinkButton>
<TextBlock x:Name="txtFilterCount" Text="{Binding ContactNumber, Mode=TwoWay}"></TextBlock>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
<Style x:Key="styleFont" TargetType="HyperlinkButton">
<Setter Property="FontFamily" Value="Verdana"></Setter>
</Style>
I have written a style that sets the font family to HyperlinkButton control.
Now i want to set this fontfamily from code behind because i am getting the value at runtime. so how to change it and one more thing i want to do this at the constructor or page load event i.e. i want to set this only once and it should apply for all the items i.e if there are 100 items then it should get applied to all the 100 items. so it makes it faster instead of always binding it any event.
The easiest way to do this is to bind the style to a property of the UserControl using the following XAML:
<Style x:Key="styleFont" TargetType="HyperlinkButton">
<Setter Property="FontFamily"
Value="{Binding DataContext.ListFont,
RelativeSource={RelativeSource AncestorType=UserControl}}">
</Setter>
</Style>
Then you just need to update the property and the style will reflect the new Font for all the list items.
Update:
This answer is only valid for Silverlight 5.
In reading a post about TreeView and binding to a view model (http://www.codeproject.com/KB/WPF/TreeViewWithViewModel.aspx), it seems that binding a TreeViewItem IsSelected property is possible. However, I have the following code which always fails on Initialize() because it's trying to set a read-only property?
<sdk:TreeView Grid.Column="0" Grid.Row="2" Style="{StaticResource TreeViewStyle}"
ItemsSource="{Binding tvData}" >
<sdk:TreeView.ItemContainerStyle>
<Style TargetType="sdk:TreeViewItem">
<Setter Property="IsEnabled" Value="True" />
<Setter Property="IsExpanded" Value="True" />
<Setter Property="IsSelected" Value="{Binding IsSelected, Mode=TwoWay}" />
</Style>
</sdk:TreeView.ItemContainerStyle>
<sdk:TreeView.ItemTemplate>
<sdk:HierarchicalDataTemplate ItemsSource="{Binding Children}">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding ItemName}" FontWeight="{Binding ItemFontWeight}"/>
</StackPanel>
</sdk:HierarchicalDataTemplate>
</sdk:TreeView.ItemTemplate>
You can't assign a binding via a Setter in a Style. Effectively what you are doing there is attempting to set a binding on the Setter.Value property. Xaml doesn't infer that you mean to set a binding on the target property. In turn the Setter just assumes you are trying to set a value directly to IsSelected which it knows is read only hence the error.
I can recommend this technique for getting around the problem:
http://blogs.msdn.com/b/delay/archive/2009/05/07/one-more-platform-difference-more-or-less-tamed-settervaluebindinghelper-makes-silverlight-setters-better.aspx
EDIT:
I should mention that I have not tried the technique for this exact scenario (binding the IsSelected property of a TreeViewItem), but I have used it on numerous other occasions, and so far it has worked flawlessly.