How to bind a ListBox item to a user control? - c#

People use frequently something like:
<ListBox ItemsSource="{Binding ElementName=thisControl, Path=ListIndexes}">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel>
<Label Content="{Binding Path=IndexName}"/>
<Label Content="{Binding Path=IndexValue}"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
But I would like to use, instead of labels, a control, like this:
<ListBox ItemsSource="{Binding ElementName=thisControl, Path=ListIndexes}">
<ListBox.ItemTemplate>
<DataTemplate>
<local:Index Item="**{Binding}**"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
My doubt is what to put into this Binding to include the whole item from the collection.

The syntax for this is:
<local:Index Item="{Binding}"/>
This will tell the data binding functions to bind the entire datacontext for each ListBox Item to the Item property in your Index control

Related

Unable to bind collection to ComboBox in silverlight

I've a ObservableCollection, when I want to display this ObservableCollection with CheckBox I am simply binding the contents to CheckBox but when I want to display the same collection by using ComboBox I am unable to do that. Any suggestions?
XAML: Display collection using CheckBox --WORKS
<ItemsControl ItemsSource="{Binding Synonyms}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" Margin="0,5,0,0" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<!--Display items in CheckBox-->
<CheckBox Content="{Binding Display}" Margin="10,0,0,0" /> // Display is the collection.
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
Output:
XAML: Display collection using ComboBox --NOTHING OVER HERE
<ItemsControl ItemsSource="{Binding Synonyms}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" Margin="0,5,0,0" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<!--Display items in ComboBox.-->
Approach - 1
<ComboBox>
<ComboBoxItem Content="{Binding Display}"/>
</ComboBox>
Approach - 2
<ComboBox ItemsSource="{Binding Path=Synonyms}" DisplayMemberPath="Display"/>
Approach - 3
<ComboBox >
<ComboBox.ItemTemplate>
<DataTemplate>
<Border BorderBrush="Green" BorderThickness="1" Padding="5">
<TextBlock Text="{Binding Path=Display,StringFormat='Display: {0}'}" />
</Border>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
Output:
I want to display items(one,two,three, etc.) inside oneComboBox with Select All option. I've tried several approaches but nothing. What am I missing here?
The checkbox is not designed to hold multiple items unlike the Combobox so implementing a system designed for the checkbox is not relevant for the combobox.
To solve your issue, remove the combobox from the ItemsControl and have it stand on its own:
<ComboBox ItemsSource="{Binding Synonyms}" DisplayMemberPath="Display"/>
Which tells the combobox to bind its ItemsSource to the data context which is unspecified, which is fine, so it then gets it's parent's data context. That process works its way up to each parent until it finds a bound data context (most likely the page's datacontext to a VM instance).
Assuming that the data context is valid at some point in the visual tree, it will bind to that instance and look for a property named Synonyms. From the Synonyms property it will use that as a list to display items.
To show (display) text in the combobox (instead defaulting to the item's ToString()) the combobox will show the string from the item's property Display.
Giving a list of items in one drop down.
The short answer, is you should use a ComboBox as the root element, not ItemsControl. CompboBox is just a specialized version of ItemsControl.
<ComboBox ItemsSource="{Binding Synonyms}" DisplayMemberPath="Display"/>
The longer answer.
ComboBox derives from ItemsControl, so you get all the features the base class, plus additional features.
ItemsControl (and its derived classes) provides a way of repeating a set of data in the UI. The DataTemplate is where you specify what UI you want for each "row" of data in the Synonyms source.
What you are doing is asking Silverlight to create a separate ComboBox for each underlying data row.
You can still use a DataTemplate within the ComboBox. Like this.
<ComboBox ItemsSource="{Binding Synonyms}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<!--Display items in CheckBox-->
<TextBox Text="{Binding Display}"
Margin="10,0,0,0"
FontWeight="Bold" />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>

How to bind properties of one ObservableCollection of ListView to properties of SelectedItem of another ListView?

So I have a few ListViews. The first is binded to ObservaleCollection<ComPort>. All properties of ComPort may take some predefined values. Other ListViews are responsible for that properties: they show all that possible (predefined) values and SelectedItem should be the current value of that property of ComPort from the first ObservaleCollection.
I can't attach images so here is an external picture, it would make the situation clean: http://i.stack.imgur.com/ZBRRx.png
<Window.Resources>
<ResourceDictionary x:Name="rd">
<l:ComPorts x:Key="vComPorts"/>
<l:SystemPorts x:Key="vSystemPorts"/>
<l:BaudRates x:Key="vBaudRate"/>
<l:Parities x:Key="vParities"/>
<l:DataBits x:Key="vDataBits"/>
<l:StopBits x:Key="vStopBits"/>
<l:Timeouts x:Key="vTimeouts"/>
<l:ComPort x:Key="vSelectedPort"/>
</ResourceDictionary>
</Window.Resources>
...
<ListView
Name="PortsList"
Grid.Row="1"
Grid.Column="0"
Margin="5"
VerticalAlignment="Stretch"
ItemsSource="{StaticResource vComPorts}"
DataContext="{StaticResource vComPorts}"
SelectedValuePath="PortName"
SelectedValue="{Binding ElementName=SystemPortsList, Path=SelectedItem.Value}"
SelectionChanged="PortsList_SelectionChanged"
MouseDoubleClick="PortsList_MouseDoubleClick">
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<CheckBox />
<TextBlock Margin="5,0,0,0" Text="{Binding Path=Name}" />
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<ListView
x:Name="SystemPortsList"
Margin="5"
VerticalAlignment="Stretch"
DataContext="{Binding Source={StaticResource vSelectedPort}}"
ItemsSource="{Binding Source={StaticResource vSystemPortsView}}"
SelectedItem="{Binding Source={StaticResource vSelectedPort}, Path=PortName}"
MouseEnter="SystemPortsList_Refresh"
MouseLeave="SystemPortsList_Refresh"
Grid.Row="1"
Grid.Column="1" SelectionChanged="SystemPortsList_SelectionChanged">
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Name="tb" Margin="5,0,0,0" Text="{Binding Path=Name}" />
</StackPanel>
</ListView.ItemTemplate>
</ListView>
I've tried to make an instance of class ComPort for saving current value of selected item from the first ListView, but anyway I can't cope with it without help. How this task should be solved?
1) Instead of handling SelectionChanged on the PortsList ListView, bind your checkbox to the ListViewItemsPanel like so:
<CheckBox IsChecked={Binding IsSelected, RelativeSource=Parent/>
2) Add an x:Name to your first ListBox, say x:Name="ComPortLB";
3) Remove DataContext on SystemPortsList;
4) Fix SelectedItem on SystemPortsList like so:
SelectedValue="{Binding ElementName=ComPortLB, Path=SelectedValue.PortName}"
I haven't tested any of this code and I haven't done this kind of stuff for a while, so I apologize for errors, but it should get you closer. I've also had to make some assumptions about your classes since you don't provide enough information.

Select only one item in two ListViews

I have two ListView, each bound to a specific collection in my ViewModel and I want to be able to select only one item globally.
Each ListView has its SelectedItem property bound to the same property in the ViewModel.
My probleme is as follow: when I select an item in a ListView, and then select another item in the other ListView, the first item stays selected.
I could achieve this with some code-behind, but I want to know if a pure XAML solution exists.
XAML:
<ListView SelectionMode="Single" ItemsSource="{Binding Path=MyList1}" SelectedItem="{Binding Path=MySelectedItem}">
<ListView.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Name}" />
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<ListView SelectionMode="Single" ItemsSource="{Binding Path=MyList2}" SelectedItem="{Binding Path=MySelectedItem}">
<ListView.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Title}" />
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
I finally got it working, by just replacing SelectedItem by SelectedValue.
In this use case, both properties have the same behaviour, but the latter one handles correctly the unselection if the bound selected item is not in the list.
You need to use Mode=TwoWay in your SelectedItem. It should work.

How do I bind a WPF ListView to a property of each element in a list?

I have the following binding on my ListView, which works fine:
<ListView ItemsSource="{Binding Filters}" Margin="5" Name="FiltersList" Height="100"/>
Filters is actually a type of List<LogFilter>. LogFilters have a property on them called Title. I would like to show the Title of each element in the Filters list in my ListView instead. Is this possible? Something like ItemsSource="{Binding Filters.Title}"?
Just set the ItemTemplate to display the title:
<ListView ItemsSource="{Binding Filters}">
<ListView.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Title}"></TextBlock>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
It seems to me that you don't need to use ListView at all. For your needs ListBox with DisplayMemberPath would be enough:
<ListBox ItemsSource="{Binding Filters}" DisplayMemberPath="Title"/>

XAML layout ItemsControl

I have searched extensively on Google and am struggling to find an easy example to follow for an ItemsControl which I think I need to be able to do the following.
I currently have a Grid with a scrollable Listbox containing Checkboxes which works as expected using the following XAML layout
<Grid>
<ListBox ScrollViewer.VerticalScrollBarVisibility="Auto"
ItemsSource="{Binding Selections}" Margin="12,22,12,94">
<ListBox.ItemTemplate>
<DataTemplate>
<CheckBox IsChecked="{Binding IsChecked}"
Content="{Binding Path=Item.SelectionName}">
</CheckBox>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
I now want to add a TextBox to the right of each Checkbox so it's aligned horizontally with 1 Checkbox and 1 Textbox per row. I thought I would have to use an ItemsControl to allow two controls but using the ItemsControl as below I lose the ability to scroll
<Grid>
<ItemsControl ScrollViewer.VerticalScrollBarVisibility="Auto"
ItemsSource="{Binding Selections}" Margin="12,22,12,94">
<ItemsControl.ItemTemplate>
<DataTemplate>
<CheckBox IsChecked="{Binding IsChecked}"
Content="{Binding Path=Item.SelectionName}">
</CheckBox>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Grid>
Also, if I try and add a textbox similar to
<DataTemplate>
<CheckBox IsChecked="{Binding sChecked}" Content="{Binding Path=Item.BookieName}" />
<TextBox />
</DataTemplate>
I get an error The object 'DataTemplate' already has a child and cannot add 'TextBox'
Essentially, I want it to look like this
Can anyone give me a few pointers on how to structure the controls in XAML to get my desired layout?
Just use a StackPanel in your DataTemplate and set the orientation to horizontal.
<DataTemplate>
<StackPanel Orientation="Horizontal">
<CheckBox IsChecked="{Binding sChecked}" Content="{Binding Path=Item.BookieName}" />
<TextBox />
</StackPanel>
</DataTemplate>

Categories