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C# WPF Loop & Delete Checked ListView Items

As someone who has recently switched from WinForms to WPF, I'm still struggling and going nuts trying to figure out a way to loop through and delete checked ListView items.
This method gives me error: "ListView does not contain a definition for CheckedItems..."
if (lvFilesList != null)
{
foreach (ListViewItem lvItem in lvFilesList.CheckedItems)
{
lvItem.Checked = False;
}
}
My XAML Code:
<ListView Height="400" Width="400"
Name="lvFilesList"
ItemsSource="{Binding}"
IsSynchronizedWithCurrentItem="True">
<ListView.View>
<GridView>
<GridView.Columns>
<GridViewColumn>
<GridViewColumn.CellTemplate>
<DataTemplate>
<CheckBox Name="chk" IsChecked="{Binding IsChecked, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"></CheckBox>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="ID" DisplayMemberBinding="{Binding ID}"/>
<GridViewColumn Header="File" DisplayMemberBinding="{Binding File}"/>
<GridViewColumn Header="Author" DisplayMemberBinding="{Binding Author}"/>
</GridView.Columns>
</GridView>
</ListView.View>
<ListView.GroupStyle>
<GroupStyle>
<GroupStyle.HeaderTemplate>
<DataTemplate>
<TextBlock FontWeight="Bold" Text="Group"/>
</DataTemplate>
</GroupStyle.HeaderTemplate>
</GroupStyle>
</ListView.GroupStyle>
</ListView>

It looks odd that the ItemsSource of your ListView is directly bound to the current DataContext by
ItemsSource="{Binding}"
The DataContext would usually hold a view model object with a collection-type property like
public class Item
{
public bool IsChecked { get; set; }
// other properties like ID, File, Author
}
public class ViewModel
{
public ObservableCollection<Item> Items { get; }
= new ObservableCollection<Item>();
}
and the Binding would be
ItemsSource="{Binding Items}"
Then the view model could have a method that deletes all checked items, like
public void DeleteCheckedItems()
{
var checkedItems = Items.Where(item => item.IsChecked).ToList();
checkedItems.ForEach(item => Items.Remove(item));
}
Note that you usually assign an instance of the view model class to the DataContext of your main view, e.g. in the MainWindow constructor:
private readonly ViewModel viewModel = new ViewModel();
public MainWindow()
{
InitializeComponent();
DataContext = viewModel;
viewModel.Items.Add(new Item { ID = 1, ... });
viewModel.Items.Add(new Item { ID = 2, ... });
}

ListView with Dictionary

Hello I'm looking for a way to use listview with Dictionary.
public class ServiceDataObject : IEquatable<ServiceDataObject>
{
public int ServiceID { get; set; }
public string ServiceName { get; set; }
public bool Status { get; set; }
public string ReccomendedStatus { get; set; }
public string WhoMade { get; set; }
public bool Equals(ServiceDataObject other)
{
if (other == null) return false;
return (this.ServiceID.Equals(other.ServiceID));
}
}
public static Dictionary<int, ServiceDataObject> ServiceData = new Dictionary<int, ServiceDataObject>();
This is how my dictionary looks like.
lvUsers.ItemsSource = Order_CONTROLS.ServiceData;
This is how I assign data to listview
And lvUsers listview:
<ListView Margin="10" Name="lvUsers">
<ListView.View>
<GridView>
<GridViewColumn>
<GridViewColumn.CellTemplate>
<DataTemplate>
<RadioButton IsChecked="{Binding Status}" GroupName="{Binding ServiceName}"/>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn>
<GridViewColumn.CellTemplate>
<DataTemplate>
<DataTemplate.Resources>
<local:InvertBooleanConverter x:Key="InvertBooleanConverter" />
</DataTemplate.Resources>
<RadioButton IsChecked="{Binding Status, Converter={StaticResource InvertBooleanConverter}}" GroupName="{Binding ServiceName}" />
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="Reccomendation" Width="120" DisplayMemberBinding="{Binding ReccomendedStatus}" />
<GridViewColumn Header="Description" Width="50" DisplayMemberBinding="{Binding ServiceName}" />
</GridView>
</ListView.View>
Problem is that it does not print data to items only correct, only number of rows are correct, but no data output, can anyone tell what I did wrong and if possible without using LIST(T)?

The solution is to set Values Collection to ItemsSource of the ListView:
lvUsers.ItemsSource = Order_CONTROLS.ServiceData.Values;
Remember also that Dictionary isn't Observable -> INotifyCollectionChanged & INotifyPropertyChanged interfaces aren't implemented.
So if you add a new element to the dictionary, your view will not see this change.

How to change each columns item font size in WPF

I want to change each columns font size. I am using listview with Gridview. I want the result something like this:
Here is my XML Code:
<ListView x:Name="listView1" Margin="0,0,-5,-5" FontSize="20">
<ListView.View>
<GridView>
<GridViewColumn Header="Column1" DisplayMemberBinding="{Binding c1}" />
<GridViewColumn Header="Column2" DisplayMemberBinding="{Binding c2}" Width="780"/>
<GridViewColumn Header="Column3" DisplayMemberBinding="{Binding c3}" Width="460"/>
</GridView>
</ListView.View>
</ListView>
C#:
this.listView1.Items.Add(new MyItem { c1= "This is Column 1 Row 1 Text", c2="This is Column 2 Row 1 Text", c3= "This is Column 3 Row 1 Text" });
class MyItem
{
public string c1{ get; set; }
public string c2{ get; set; }
public string c3{ get; set; }
}

You can always use the CellTemplate instead of DisplayMemberBinding to have full customization options.
For the first column something like:
<GridViewColumn Header="Column1">
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock Text="{Binding c1}" FontSize="15px"/>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>

Create columns dynamically in a GridView in WPF MVVM

My MVVM WPF application currently has a GridView that binds to a ViewModel property and has the columns defined in the XAML:
<ListView Grid.Row="0" ItemsSource="{Binding GroupedOrders}">
<ListView.View>
<GridView>
<GridViewColumn>
<GridViewColumn.CellTemplate>
<DataTemplate>
<CheckBox IsChecked="{Binding Item2, Mode=OneWay}" />
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="Date" DisplayMemberBinding="{Binding Item1.Date, StringFormat={}{0:dd/MM/yyyy}}" />
<GridViewColumn Header="Name" DisplayMemberBinding="{Binding Item1.Name}" />
<!-- lots more -->
</GridView>
</ListView.View>
</ListView>
GroupedOrders is an ObservableCollection of a Tuple of two different item types: an "Order" object and a Boolean that controls whether or not, for this particular view, it is "selected".
However, that "selected" property hasn't been modelled well. It's come to light that each Order needs multiple "selected" properties, depending on the number of dates in the order, which can be between one and five.
To model this in the UI, I need to replace that single Checkbox GridViewColumn with a dynamic construct that creates a similar Checkbox GridviewColumn for each date in the order. So GroupedOrders becomes a Tuple <Order, List<bool>> instead, and there will need to be one column for each bool in the List.
At any given instance, the size of that list will be the same for all the Orders in the grid. But if the user loads new data into the grid, the size of the list will change.
However, I cannot see how to do this in MVVM. Existing solutions seem to be for code-behind where the GridView can be grabbed as an object and manipulated on the fly. The only MVVM solution I've seen to this is to use a Converter to building the entire GridView on the fly, which would seem to be massive overkill for this situation, where there are a lot of columns in the GridView but only a small number need to be dynamic.
Is there another way?

Not sure this is what you expect, but this is what I can think of.
View
<ListView ItemsSource="{Binding Orders}">
<ListView.View>
<GridView>
<GridViewColumn Header="State">
<GridViewColumn.CellTemplate>
<DataTemplate>
<ListView ItemsSource="{Binding States}">
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal"></StackPanel>
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.Resources>
<Style TargetType="GridViewColumnHeader">
<Setter Property="Visibility" Value="Collapsed" />
</Style>
</ListView.Resources>
<ListView.View>
<GridView>
<GridViewColumn>
<GridViewColumn.CellTemplate>
<DataTemplate>
<CheckBox IsChecked="{Binding Value}" Content="{Binding Text}" />
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
</GridView>
</ListView.View>
</ListView>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="OrderNo" DisplayMemberBinding="{Binding OrderNo}" />
</GridView>
</ListView.View>
</ListView>
Code Behind
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
Orders.Add(new Order { OrderNo = "Order001" });
Orders.Add(new Order { OrderNo = "Order002" });
Orders.Add(new Order { OrderNo = "Order003" });
}
private readonly ObservableCollection<Order> _orders = new ObservableCollection<Order>();
public ObservableCollection<Order> Orders
{
get { return _orders; }
}
}
public class Order
{
public Order()
{
States.Add(new State { Text = "Is Paid", Value = false });
States.Add(new State { Text = "Is Delivered", Value = false });
}
public string OrderNo { get; set; }
private readonly ObservableCollection<State> _states = new ObservableCollection<State>();
public ObservableCollection<State> States
{
get { return _states; }
}
}
public class State
{
public string Text { get; set; }
public bool Value { get; set; }
}
Result

WPF Listview databinding to generic List, dynamically filled by WCF service

In WPF app I have a WCF service which dynamically fills a generic List object from a backend database.
How in this case (List created in runtime), I could bind List items to a ListView object items?
It is the Data contract for my Web service:
....
[DataContract]
public class MeetList
{
[DataMember]
public string MeetDate;
[DataMember]
public string MeetTime;
[DataMember]
public string MeetDescr;
.....
static internal List<MeetList> LoadMeetings(string dynamicsNavXml)
{
...// Loads XML stream into the WCF type
}
Here in this event handler I read the WCF service and Loop through a List object:
private void AllMeetings()
{
Customer_ServiceClient service = new Customer_ServiceClient();
foreach (MeetList meet in service.ReadMeetList())
{
?????? = meet.MeetDate; // it's here that I bumped into a problem
?????? = meet.MeetTime; //
?????? = meet.MeetDescr;//
}
}
My Listview XAML:
<Grid>
<ListView Height="100" Width="434" Margin="0,22,0,0" Name="lvItems" ItemsSource="{Binding}" IsSynchronizedWithCurrentItem="True" SelectionMode="Single">
<ListView.View>
<GridView>
<GridViewColumn Header="Date" Width="100" HeaderTemplate="{StaticResource DateHeader}" CellTemplate="{DynamicResource DateCell}"/>
<GridViewColumn Header="Time" Width="100" HeaderTemplate="{StaticResource TimeHeader}" CellTemplate="{DynamicResource TimeCell}"/>
<GridViewColumn Header="Description" Width="200" HeaderTemplate="{StaticResource DescriptionHeader}" CellTemplate="{DynamicResource DescriptionCell}"/>
</GridView>
</ListView.View>
</ListView>
</Grid>
And data templates for this ListView:
<Window.Resources>
<DataTemplate x:Key="DateHeader">
<StackPanel Orientation="Horizontal">
<TextBlock Margin="10,0,0,0" Text="Date" VerticalAlignment="Center" />
</StackPanel>
</DataTemplate>
<DataTemplate x:Key="DateCell" DataType="Profile">
<StackPanel Orientation="Horizontal">
<TextBlock>
<TextBlock.Text>
<Binding Path="MeetDate" />
</TextBlock.Text>
</TextBlock>
</StackPanel>
</DataTemplate>
......
How in this case (List created in runtime), I could bind my generic List items to a ListView object items?
I tried to use lvItems.ItemsSource = profiles; , but it doesn't work in my event handler

List doesn't have behaviour to notify that items count is changed. You should use a list with support INotifyCollectionChanged.. for example: ObservableCollection<T>. ObservableCollection<T> will inform your lvItems that items count is changed and it will be properly display.

Using intermediate ObservableCollection:
ObservableCollection<Meets> _MeetCollection =
new ObservableCollection<Meets>();
public ObservableCollection<Meets> MeetCollection
{ get { return _MeetCollection; } }
public class Meets
{
public string Date { get; set; }
public string Time { get; set; }
public string Description { get; set; }
}
In the event handler loop we put:
private void AllMeetings()
{
Customer_ServiceClient service = new Customer_ServiceClient();
_MeetCollection.Clear();
foreach (MeetList meet in service.ReadMeetList())
{
_MeetCollection.Add(new Meets
{
Date = meet.MeetDate,
Time = meet.MeetTime,
Description = meet.MeetDescr
});
}
}
And XAML binding is changed to:
<Grid>
<ListView Height="100" Width="434" Margin="0,22,0,0" Name="lvItems" ItemsSource="{Binding MeetCollection}">
<ListView.View>
<GridView>
<GridViewColumn Header="Date" Width="100" DisplayMemberBinding="{Binding Date}"/>
<GridViewColumn Header="Time" Width="100" DisplayMemberBinding="{Binding Time}"/>
<GridViewColumn Header="Description" Width="200" DisplayMemberBinding="{Binding Description}"/>
</GridView>
</ListView.View>
</ListView>
</Grid>