I have a template column in a DataGrid:
<sdk:DataGridTemplateColumn.CellEditingTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" VerticalAlignment="Center" >
<TextBlock Text="{Binding Name,ElementName=rsAllSkills}"/>
</StackPanel>
</DataTemplate>
</sdk:DataGridTemplateColumn.CellEditingTemplate>
And in the same xaml file, I have
<riaControls:DomainDataSource QueryName="GetSkillsQuery" AutoLoad="True" x:Name="rsAllSkills">
<riaControls:DomainDataSource.DomainContext>
<domain:XXXX context/>
</riaControls:DomainDataSource.DomainContext>
</riaControls:DomainDataSource>
The DataSource has loaded everything successfully for sure, if I put that TextBlock out side of the DataGrid, it works; but inside the DataGrid, it doesn't load even the Name of rsAllSkills....
Could anybody give me a hint, thank you so much.
Have a dummy converter and check the binding.
What I guess is, the DataTemplate inside the CellEditingTemplate would receive the parent's DataContext, ie., DataGrid's DataContext. So, to work around this you can do one thing.
1) Bind the rsAllSkills to the Tag Property of DataGridTemplateColumn.
2) Now, Bind the TextBlock's Text property with the Tag property like,
<sdk:DataGridTemplateColumn Tag="{Binding Name,ElementName=rsAllSkills}">
<sdk:DataGridTemplateColumn.CellEditingTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" VerticalAlignment="Center" >
<TextBlock Text="{Binding Tag}"/>
</StackPanel>
</DataTemplate>
</sdk:DataGridTemplateColumn.CellEditingTemplate>
</sdk:DataGridTemplateColumn>
Related
I have a Data Grid that is bound to a object of type MyStaff. Apart from other properties MyStaff contains a column named LookupID. Now, in my ViewModel I have a collection Named Lookups that have a description for each LookupID.
I have a Template column that has a Textblock in Cell Template and Combobox in CellEdit Template. How do I bind the Textblock so that it dsiplays the description from ComboBox based on LookupID.
I know it would be pretty simple if the datacontext for both the Textblock and ComboBox were simple but that is not the case.
I have tried this but this doesn't work. Any suggestions? Also would appreciate any information on how to best use different Data Context for different controls in Silverlight. For this I have added a static resource pointing to the ViewModel Class.
<sdk:DataGridTemplateColumn Header="Action Point"
Width="500"
CanUserReorder="False"
HeaderStyle="{StaticResource dthFull2}"
IsReadOnly="False">
<sdk:DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<TextBlock
Text="{Binding ElementName=LookupList,
Path=SelectedItem.Description}"
MinHeight="24"
VerticalAlignment="Top"
Padding="2"
TextTrimming="WordEllipsis"/>
</DataTemplate>
</sdk:DataGridTemplateColumn.CellTemplate>
<sdk:DataGridTemplateColumn.CellEditingTemplate>
<DataTemplate>
<my:AutoCompleteComboBox x:Name="LookupList"
FilterMode="Custom" Margin="2,0,0,0"
SelectedValue="{Binding LookupID, Mode=TwoWay}"
SelectedValuePath="LookupID"
ItemsSource="{Binding Path=AnalysisLookupList.Values,
Source={StaticResource ViewModel}}"/>
</DataTemplate>
</sdk:DataGridTemplateColumn.CellEditingTemplate>
</sdk:DataGridTemplateColumn>
I have a ComboBox that shows text of various lengths. For texts that are not long there is not a problem. For the texts longer than the width of ComboBox I would like to trim the text and add "..." (an ellipsis) at the end to show them properly. The bottom line is that I don't want to change the width of the ComboBox. Does anyone know how to do this?
Use a custom ItemTemplate for your ComboBox, which makes use of a TextBlock with the TextTrimming property set to CharacterEllipsis.
Example:
<ComboBox ItemsSource="..." SelectedValuePath="...">
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock
Text="{Binding ...}"
TextTrimming="CharacterEllipsis" />
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
The answer, as Ross said, is to implement a custom ItemTemplate. However, to make it work properly, you need to do the binding properly.
A note on this method: You cannot set both the DisplayMemberPath and the ItemTemplate, it must be one or the other.
So, for the general case where the display member is the item (such as for a string), you can use binding with no properties to bind to the DataContext of the template:
<ComboBox ItemsSource="..." SelectedValuePath="...">
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding }" TextTrimming="CharacterEllipsis" />
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
Or, you can put it in a style.
<Style TargetType="{x:Type ComboBox}">
<Setter Property="ItemTemplate">
<Setter.Value>
<DataTemplate>
<TextBlock Text="{Binding }" TextTrimming="CharacterEllipsis" />
</DataTemplate>
</Setter.Value>
</Setter>
</Style>
For the case where you want to bind to a specific property of the object, similar to how you would use the DisplayMemberPath property, replace the binding with the binding that you would use to a property on the object that you are binding. So, replace the fourth line in my first example with something like this:
<TextBlock Text="{Binding MyDisplayMemberProperty}" TextTrimming="CharacterEllipsis" />
The binding is in the context of a single item of the type bound to your ComboBox. To make this more explicit, you can do the following:
<DataTemplate DataType="{x:Type namespace:MyItemType}">
<!-- My DataTemplate stuff here -->
</DataTemplate>
This will give you hints for the properties on the object while you are writing code inside the DataTemplate.
You can use TextTrimming CharacterEllipsis or WordEllipsis for the textblocks in your combobox.
Also works with a more complex DataTemplate; however, I had to resort to a DockPanel instead of the standard WrapPanel.
<ComboBox>
<ComboBox.ItemTemplate>
<DataTemplate>
<DockPanel>
<AccessText DockPanel.Dock="Left" Text="{Binding Icon}"/>
<TextBlock Text="{Binding Name}" TextTrimming="CharacterEllipsis" />
</DockPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
I have the following xaml code:
<ListBox Foreground="{Binding MyColor, Converter={local:ColorConverter}}" ItemsSource="{Binding LogCollection, Mode=TwoWay}" Grid.Row="1">
</ListBox>
This changes the foreground color for the entire listbox, so I modified the code in this way:
<ListBox ItemsSource="{Binding LogCollection, Mode=TwoWay}" Grid.Row="1">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBlock Foreground="{Binding MyColor, Converter={local:ColorConverter}}" Text="{Binding}"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
In this way I wanted to set the foreground for an item instead for the entire listbox, but it is not working. How do I find the right datacontext ? MyColor is a property on my MainViewModel.
LATER EDIT WITH THE SOLUTION
Jens's answer was the one that showed me where I was wrong. Instead of storing simple message log strings in the ObservableCollection, I created a new class (LogItems) which contains a Message and a Color members. Now the LogCollection is typeof LogItems instead of strings.
I populate the listbox with the following code in my viewmodel:
LogItems logitem = new LogItems(myMessage, myColor);
LogCollection.Insert(0, logitem);
And the view has the following form. Also it doesn't require anymore to use RelativeSource, because the datacontext is the same.
<ListBox ItemsSource="{Binding LogCollection, Mode=TwoWay}" Grid.Row="1">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBlock Foreground="{Binding Path=Color, Converter={local:ColorConverter}}" Text="{Binding Path=Message}"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
Thank you all for your answers which lead me to this solution.
The DataContext of generated container in a listbox is automatically set to the corresponding item, therefore your Binding does not find the Property MyColor. You need to use a RelativeSource binding to bind to the DataContext of the containing list:
<TextBlock Foreground="{Binding DataContext.MyColor,
RelativeSource={RelativeSource
Mode=FindAncestor,
AncestorType={x:Type ListBox}},
Converter={local:ColorConverter}}"
Text="{Binding}"/>
I have a form:
<StackPanel Orientation="Horizontal" Visibility="{Binding Editable, Converter={StaticResource visibilityConverter}}"
ToolTipService.ToolTip="Add new topic to this group">
<sdk:AutoCompleteBox Width="160" ItemsSource="{Binding ElementName=LayoutRoot, Path=DataContext.TopicNames}" />
<Button Click="addTopicButton_Click">
<Image Source="Images/appbar.add.rest.png" />
</Button>
</StackPanel>
This form appears in a DataTemplate for an ItemsControl. I'm not sure what the best way is to get the data from the AutoCompleteBox when the button is clicked. I can't give the elements x:Name attributes, because they're in a template (right?).
How can I get around this? The Click event will give me the Button, but I need a reference to the text box. Use the Button's parent, then look through the children for the Textbox? If I factored this out into its own UserControl, I could set x:Name values, but I'd rather not do that.
Any other ideas?
Update: Here is another example of such a problem:
<ListBox x:Name="topicList"
ItemsSource="{Binding Id, Converter={StaticResource topicGroupIDConverter}}"
SelectionChanged="ListBox_SelectionChanged"
HorizontalAlignment="Stretch">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Name}"
Width="150"
VerticalAlignment="Center"
ToolTipService.ToolTip="{Binding Description}"
ToolTipService.Placement="Right" />
<Button ToolTipService.ToolTip="Remove this topic from this group"
Visibility="{Binding ElementName=topicList,
Path=DataContext.Editable,
Converter={StaticResource visibilityConverter}}"
Click="removeTopicButton_Click"
HorizontalAlignment="Right"
Margin="10,0">
<Image Source="Images/appbar.cancel.rest.png" />
</Button>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
When the button is clicked, I want to access topicList.DataContext. However, topicList itself is a DataTemplate in an ItemsControl, so I can't access it using its name from code-behind. How else can I do this?
You can add a property, say SelectedItemInAutoCompleteBox, to your presenter, and then can bind it to the SelectedItem property of AutoCompleteBox, using Mode=TwoWay, like this,
<sdk:AutoCompleteBox SelectedItem="{Binding Path=DataContext.SelectedItemInAutoCompleteBox, Mode=TwoWay}" ... />
You may try the same approach with Text property of AutoCompleteBox, also. See if it solves your problem.:-)
You have several choices:
If you're on Silverlight 5, use the AncestorBinding
Otherwise, use a Silverlight 4 AncestorBinding hack (it doesn't look pretty)
Or you could try DataContextProxy, which stores the DataContext in a resource so that it is accessible. Note: you should set the DataContextProxy as a Resource of topicList ListBox, not the UserControl as in Dan Wahlin's example.
Given a silverlight datagrid with RowDetailsVisibilityMode="VisibleWhenSelected", on clicking a row in the datagrid, how do you set or bind the controls in the RowDetailsVisibilityChanged() event?
<data:DataGrid.RowDetailsTemplate>
<DataTemplate>
<StackPanel>
<TextBlock Text="a" x:Name="_txt" />
<ListBox x:Name="_lst"></ListBox>
</StackPanel>
</DataTemplate>
</data:DataGrid.RowDetailsTemplate>
You don't need to code the rowsvisibilitychanged event, Silverlight will do the binding for you automatically if you set up binding in your data template. Simply use {Binding col_name}.
A simplified example, binding happens automatically as user clicks a row.
<sdk:DataGrid RowDetailsVisibilityMode='VisibleWhenSelected'
ItemsSource='{Binding ElementName=ld_linkDomainDataSource, Path=Data}'>
<data:DataGrid.RowDetailsTemplate>
<DataTemplate>
<StackPanel>
<TextBlock Text='Link Name: '/>
<TextBox Text='{Binding link_name}'/> <-- column from ItemsSource
</StackPanel>
</DataTemplate>
</data:DataGrid.RowDetailsTemplate>