I try to pass from simple binding to MultiBinding for CommandParameter but can not find out the syntax for "{Binding}" in the following example for the multibinding example below. Thanks a lot for any hint !
Regards, Fabianus
<Button Content="Add subevent" HorizontalAlignment="Left" MinWidth="100" Command="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type Window}}, Path=DataContext.AddEvent}" CommandParameter="{Binding}" />
CommandParameter with MultiBinding:
<Button Content="Add subevent" HorizontalAlignment="Left" MinWidth="100" Command="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type Window}}, Path=DataContext.AddEvent}" >
<Button.CommandParameter>
<MultiBinding Converter="{StaticResource searchFilterConverter}">
<Binding Path="" />
<Binding RelativeSource="{RelativeSource Mode=FindAncestor,AncestorType=Window}" Path="DataContext.SelectedProduct" />
</MultiBinding>
</Button.CommandParameter>
</Button>
Related
I am unable to pass the text of textblock tbAge as the second command parameter.
Though I am able to pass the first command parameter i.e. the text of tbName. Need to understand what extra i need to add ?.
<MenuItem.ItemTemplate>
<HierarchicalDataTemplate ItemsSource="{Binding Path=Students}">
<TextBlock x:Name="tbAge" Text="{Binding DisplayAge}"/>
<HierarchicalDataTemplate.ItemTemplate>
<DataTemplate>
<StackPanel>
<TextBlock x:Name="tbName" Text="{Binding}">
<TextBlock.InputBindings>
<MouseBinding Command="{Binding DataContext.NavigateToID, RelativeSource={RelativeSource AncestorType=Menu}}" MouseAction="LeftClick" >
<MouseBinding.CommandParameter>
<MultiBinding Converter="{StaticResource MultiCommandConverter}">
<Binding Path="Text" ElementName="tbName"/>
<Binding Path="Text" ElementName="tbAge" />
</MultiBinding>
</MouseBinding.CommandParameter>
</MouseBinding>
</TextBlock.InputBindings>
</TextBlock>
</StackPanel>
</DataTemplate>
</HierarchicalDataTemplate.ItemTemplate>
</HierarchicalDataTemplate>
</MenuItem.ItemTemplate>
I have a checkbox inside an ItemsControl. It has an EventTrigger both for Checked and UnChecked events. It is also bound to a Command with multiple CommandParameters. The Checked event triggers just fine.
However, the UnChecked event does not fire. What am I missing?
<ItemsControl Grid.Column ="2"
Grid.Row ="0"
ItemsSource ="{Binding ParameterOptionGroup.ParameterOptions}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal"/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<CheckBox IsChecked="{Binding State, Converter={StaticResource BoolToEntityState}, Mode=OneWay}">
<trigger:Interaction.Triggers>
<trigger:EventTrigger EventName="Checked">
<trigger:InvokeCommandAction Command ="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type UserControl}},
Path=DataContext.InitiateParameterAnswer}">
<trigger:InvokeCommandAction.CommandParameter>
<MultiBinding Converter="{StaticResource GuidAndParameterOptionToTuple}">
<Binding Path="DataContext" RelativeSource="{RelativeSource FindAncestor, AncestorType={x:Type CheckBox}}"></Binding>
<Binding Path="DataContext.Id" RelativeSource="{RelativeSource FindAncestor, AncestorType={x:Type ItemsControl}}"></Binding>
<Binding Path="Text" ElementName="txtRemarks" />
<Binding Source="True" />
<Binding Source="10" />
</MultiBinding>
</trigger:InvokeCommandAction.CommandParameter>
</trigger:InvokeCommandAction>
</trigger:EventTrigger>
</trigger:Interaction.Triggers>
<trigger:EventTrigger EventName="UnChecked">
<trigger:InvokeCommandAction Command ="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type UserControl}},
Path=DataContext.InitiateParameterAnswer}">
<trigger:InvokeCommandAction.CommandParameter>
<MultiBinding Converter="{StaticResource GuidAndParameterOptionToTuple}">
<Binding Path="DataContext" RelativeSource="{RelativeSource FindAncestor, AncestorType={x:Type CheckBox}}"></Binding>
<Binding Path="DataContext.Id" RelativeSource="{RelativeSource FindAncestor, AncestorType={x:Type ItemsControl}}"></Binding>
<Binding Path="Text" ElementName="txtRemarks" />
<Binding Source="False" />
<Binding Source="5" />
</MultiBinding>
</trigger:InvokeCommandAction.CommandParameter>
</trigger:InvokeCommandAction>
</trigger:EventTrigger>
</CheckBox>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
As #Bort pointed out, the event name should be Unchecked instead of UnChecked.
I have a ListView in my XAML and I am trying to hook up a MultiBinding Converter.
<ListView
Grid.Column="4"
Grid.Row="1"
Grid.RowSpan="5"
Margin="8,0,8,8"
HorizontalAlignment="Stretch"
Name="lvDisplayType"
ItemsSource="{Binding Path=Types}"
SelectedItem="{Binding Path=Current.Opt}"
VerticalAlignment="Stretch"
SelectionChanged="lvType_SelectionChanged"
SelectionMode="Single"
ScrollViewer.HorizontalScrollBarVisibility="Disabled">
<ListView.ItemTemplate>
<DataTemplate>
<DockPanel
HorizontalAlignment="Center">
<TextBlock
Text="{Binding Path=., Converter={StaticResource DisplayConverter}}"
HorizontalAlignment="Center"
Padding="6"
VerticalAlignment="Center"
TextWrapping="Wrap">
<TextBlock.ToolTip>
<ToolTip DataContext="{Binding Path=Current}">
<MultiBinding Converter="{StaticResource OptConverter}">
<Binding Path="Opt" />
<Binding Path="Type" />
</MultiBinding>
</ToolTip>
</TextBlock.ToolTip>
</TextBlock>
</DockPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
The code not working is:
<TextBlock.ToolTip>
<ToolTip DataContext="{Binding Path=Current}">
<MultiBinding Converter="{StaticResource OptConverter}">
<Binding Path="Opt" />
<Binding Path="Type" />
</MultiBinding>
</ToolTip>
</TextBlock.ToolTip>
At present the Converter is returning an empty string as both 'values[0] == System.Windows.DependencyProperty.UnsetValue' and 'values[1] == System.Windows.DependencyProperty.UnsetValue' return true. These values are never set.
Because of the logical tree (I think) the TextBlock.ToolTip default binding is 'Current.Opt'. For the MultiBinding I also need to refer to 'Type' which is another property of 'Current'. So to get around this I have set 'ToolTip DataContext="{Binding Path=Current}"' - this isn't working as expected - what am I doing wrong?
I know I could do this easily in the Code behind, but we are employing MVVM, so would like to avoid it if possible.
Any help greatly appreciated!
Thank you
Try to do it in this way,
1.Does this give DependencyProperty.UnsetValue in the Converter? Otherwise, what is coming in to the converter?
<TextBlock.ToolTip>
<MultiBinding Converter="{StaticResource OptConverter}">
<Binding RelativeSource="{RelativeSource Self}" />
<Binding RelativeSource="{RelativeSource Self}" />
</MultiBinding>
</TextBlock.ToolTip>
2.Does this give DependencyProperty.UnsetValue in the Converter?
<TextBlock.ToolTip>
<MultiBinding Converter="{StaticResource OptConverter}">
<Binding RelativeSource="{RelativeSource Self}" Path="Current"/>
<Binding RelativeSource="{RelativeSource Self}" Path="Current"/>
</MultiBinding>
</TextBlock.ToolTip>
At several points in my current application, I have an ItemTemplate such as the following:
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal"/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<ToggleButton Margin="2,0" Content="{Binding}" Tag="{Binding}" Click="ToggleButton_Click">
<ToggleButton.IsChecked>
<MultiBinding Mode="OneWay" Converter="{StaticResource EqualityConverter}">
<Binding RelativeSource="{RelativeSource Self}" Path="Tag">
</Binding>
<Binding RelativeSource="{RelativeSource FindAncestor, AncestorType={x:Type cc:ToggleButtonPanel}}" Path="SelectedItem">
</Binding>
</MultiBinding>
</ToggleButton.IsChecked>
</ToggleButton>
</DataTemplate>
</ItemsControl.ItemTemplate>
Now, I've stepped through the converter and it returns true and false as expected, but the controls do not change their ischecked state... There are no binding errors, and this only happens when using an ItemsTemplate/DataTemplate combo. Has anyone else seen this behaviour?
I have a ListBox:
<ListBox x:Name="HistogramListBox" Grid.Column="1" Margin="8,2,8,0"
HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
Template="{StaticResource HistogramListBoxControlTemplate}"
ItemContainerStyle="{StaticResource HistogramListBoxItem}"
ItemTemplate="{DynamicResource BucketTemplate}" />
That uses a DataTemplate that in turn uses a ValueConverter to determine the height of the ListBoxItem:
<DataTemplate x:Key="BucketTemplate">
<StackPanel>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="100"/>
</Grid.RowDefinitions>
<StackPanel HorizontalAlignment="Stretch" VerticalAlignment="Bottom">
<Rectangle Grid.Row="0" StrokeThickness="1" VerticalAlignment="Bottom"
Stroke="{Binding ElementName=MainElement, Path=BucketStroke}"
Fill="{Binding ElementName=MainElement, Path=BucketFill}" >
<Rectangle.Height>
<MultiBinding Converter="{StaticResource HistogramValueToPercentageConverter}">
<Binding Mode="OneWay" Path="ItemCount" />
<Binding RelativeSource="{RelativeSource FindAncestor, AncestorType={x:Type local:Histogram}}" />
</MultiBinding>
</Rectangle.Height>
</Rectangle>
</StackPanel>
</Grid>
</StackPanel>
</DataTemplate>
The ListBox ItemsSource is an int[].
When I execute the code it says it can't find 'ItemCount' on an Int32. I thought it got the item count from the ListBox (I'm obviously wrong).
Can someone tell me how I can get my ValueConverter to know what item I am on.
Thanks
Dan
Assuming your first converter parameter is intended to be the actual value being charted and the second the Histogram object:
<Rectangle.Height>
<MultiBinding Converter="{StaticResource HistogramValueToPercentageConverter}">
<Binding />
<Binding RelativeSource="{RelativeSource FindAncestor, AncestorType={x:Type local:Histogram}}" />
</MultiBinding>
</Rectangle.Height>
This is because the DataContext is the integer itself, at least that appears to be the case from the error message you gave.
By the way, you would normally set the ListBox's ItemsSource using a binding, not from code-behind. This leads to much cleaner separation of UI and code. I noticed no ItemsSource= was shown in your example code so I thought I should mention this.
The data context of the items in the data template is the data item itself, which is an int. If you want to a property on the ListBox, you'll need to reach outside of your current context to do so. You can use a RelativeSource to do this:
{Binding Items.Count, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListBox}}}
You can try this for your Binding:
<Binding Path="Items.Count">
<Binding.RelativeSource>
<RelativeSource AncestorType="{x:Type ListBox}" />
</Binding.RelativeSource>
</Binding>