Rank 1
hi,
I tried to execute your sample code for drag and drop but unfortunately it is throwing me some error.
In the line ListBox box = ItemsControl.ItemsControlFromItemContainer(listBoxItem) as ListBox;,it is giving error as
Error 1 'System.Windows.Controls.ItemsControl' does not contain a definition for 'ItemsControlFromItemContainer' C:\Documents and Settings\manas.rastogi\Desktop\Telerik Drag And Drop\Telerik Drag And Drop\Page.xaml.cs 127 64 Telerik Drag And Drop
i have added given the required references but still facing the same problem.
Page.xaml is:
<U
serControl x:Class="Telerik_Drag_And_Drop.Page"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Width="400" Height="300"
xmlns:panels="clr-namespace:Telerik.Windows.Controls;assembly=Telerik.Windows.Controls"
xmlns:primitives="clr-namespace:Telerik.Windows.Controls.Primitives;assembly=Telerik.Windows.Controls"
xmlns:dragDrop="clr-namespace:Telerik.Windows.Controls.DragDrop;assembly=Telerik.Windows.Controls">
<UserControl.Resources>
<DataTemplate x:Key="ApplicationDragTemplate">
<Image Source="{Binding IconPath}" Stretch="None" VerticalAlignment="Top" />
</DataTemplate>
<Style TargetType="ListBoxItem" x:Key="draggableItemStyle">
<Setter Property="HorizontalAlignment" Value="Stretch" />
<Setter Property="HorizontalContentAlignment" Value="Stretch" />
<Setter Property="dragDrop:RadDragAndDropManager.AllowDrag" Value="True" />
</Style>
</UserControl.Resources>
<Grid x:Name="LayoutRoot">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="200" />
<ColumnDefinition Width="150" />
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<!--All Applications-->
<Border CornerRadius="5" BorderBrush="Black" BorderThickness="5" Background="#FFFFFFFF">
<Grid>
<Border Height="30" VerticalAlignment="Top">
<Border.Background>
<LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
<GradientStop Color="#FF4C4C4C" />
<GradientStop Color="#FF333538" Offset="1" />
<GradientStop Color="#FF3C3D3F" Offset="0.394" />
<GradientStop Color="#FF151516" Offset="0.417" />
</LinearGradientBrush>
</Border.Background>
<TextBlock Text="All Applications:" Margin="10,5" Foreground="#FFFFFFFF"
FontSize="12" />
</Border>
<ListBox x:Name="allApplicationsBox" Margin="10 40 10 10" BorderThickness="0"
dragDrop:RadDragAndDropManager.AllowDrop="True"
ItemContainerStyle="{StaticResource draggableItemStyle}">
<ListBox.ItemTemplate>
<DataTemplate>
<Grid Width="140">
<Grid.RowDefinitions>
<RowDefinition />
<RowDefinition />
<RowDefinition />
</Grid.RowDefinitions>
<Image Grid.Row="0" HorizontalAlignment="Center"
Source="{Binding IconPath}" Width="32" Height="32"
Margin="0 0 5 0" />
<TextBlock Grid.Row="1" Text="{Binding Name}" FontWeight="Bold"
HorizontalAlignment="Center" />
<TextBlock Text="{Binding Author}" Grid.Row="2"
HorizontalAlignment="Center" />
</Grid>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
</Border>
<!--Text-->
<Border Grid.Column="1" BorderBrush="Gray" Background="LightGray" BorderThickness="1"
VerticalAlignment="Center" HorizontalAlignment="Center">
<TextBlock Text="Drag applications from All Applications to My Applications."
HorizontalAlignment="Center" TextWrapping="Wrap" Margin="10" FontSize="10" />
</Border>
<!--My Applications-->
<Border CornerRadius="5" Grid.Column="2" BorderBrush="Black" BorderThickness="5"Background="#FFFFFFFF">
<Grid>
<Border Height="30" VerticalAlignment="Top">
<Border.Background>
<LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
<GradientStop Color="#FF4C4C4C" />
<GradientStop Color="#FF333538" Offset="1" />
<GradientStop Color="#FF3C3D3F" Offset="0.394" />
<GradientStop Color="#FF151516" Offset="0.417" />
</LinearGradientBrush>
</Border.Background>
<TextBlock Text="My Applications:" Margin="10,5" Foreground="#FFFFFFFF" FontSize="12" />
</Border>
<ListBox x:Name="myApplicationsBox" Margin="10 40 10 10"
dragDrop:RadDragAndDropManager.AllowDrop="True" BorderThickness="0"
ItemContainerStyle="{StaticResource draggableItemStyle}">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel VerticalAlignment="Stretch" HorizontalAlignment="Stretch">
<Image Source="{Binding IconPath}" Margin="0 0 3 0"
HorizontalAlignment="Center" />
<TextBlock Text="{Binding Name}" HorizontalAlignment="Center" />
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<primitives:RadUniformGrid Columns="3" HorizontalAlignment="Left"
VerticalAlignment="Top" />
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
</ListBox>
</Grid>
</Border>
</Grid>
</UserControl>
The Page.xaml.cs is:
using System;
using System.Collections.Generic;
u
sing System.Collections.ObjectModel;
using System.ComponentModel;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using System.Windows.Controls.Test;
using System.Windows.Media;
using Telerik.Windows.Controls.DragDrop;
namespace
Telerik_Drag_And_Drop
{
public partial class Page : UserControl
{
public static ObservableCollection<ApplicationInfo> GenerateApplicationInfos()
{
return new ObservableCollection<ApplicationInfo>()
{
new ApplicationInfo()
{
Name =
"Large Collider",
Author =
"C.E.R.N.",
IconPath =
@"/DragAndDrop/Images/LargeIcons/Atom.png"
},
new ApplicationInfo()
{
Name =
"Paintbrush",
Author =
"Imagine Inc.",
IconPath =
@"/DragAndDrop/Images/LargeIcons/Brush.png"
},
new ApplicationInfo()
{
Name =
"Lively Calendar",
Author =
"Control AG",
IconPath =
@"/DragAndDrop/Images/LargeIcons/CalendarEvents.png"
},
new ApplicationInfo()
{
Name =
"Fire Burning ROM",
Author =
"The CD Factory",
IconPath =
@"/DragAndDrop/Images/LargeIcons/CDBurn.png"
},
new ApplicationInfo()
{
Name =
"Fav Explorer",
Author =
"Star Factory",
IconPath =
@"/DragAndDrop/Images/LargeIcons/favorites.png"
},
new ApplicationInfo()
{
Name =
"IE Fox",
Author =
"Open Org",
IconPath = @
"/DragAndDrop/Images/LargeIcons/Connected.png"
},
new ApplicationInfo()
{
Name =
"Charting",
Author =
"AA-AZ inc",
IconPath =
@"/DragAndDrop/Images/LargeIcons/ChartDot.png"
},
new ApplicationInfo()
{
Name =
"SuperPlay",
Author =
"EB Games",
IconPath =
@"/DragAndDrop/Images/LargeIcons/Games.png"
}
};
}
ObservableCollection<ApplicationInfo> allApplications = GenerateApplicationInfos();
ObservableCollection<ApplicationInfo> myApplications;
Brush listBoxDragPossible = new SolidColorBrush(Colors.Orange);
public Page()
{
InitializeComponent();
myApplications =
new ObservableCollection<ApplicationInfo>();
allApplicationsBox.ItemsSource = allApplications;
myApplicationsBox.ItemsSource = myApplications;
RadDragAndDropManager.AddDragQueryHandler(this, OnDragQuery);
RadDragAndDropManager.AddDragInfoHandler(this, OnDragInfo);
RadDragAndDropManager.AddDropQueryHandler(this, OnDropQuery);
RadDragAndDropManager.AddDropInfoHandler(this, OnDropInfo);
}
private void OnDropInfo(object sender, DragDropEventArgs e)
{
ItemsControl box = e.Options.Destination as ItemsControl;
IList<ApplicationInfo> itemsSource = box.ItemsSource as IList<ApplicationInfo>;
ApplicationInfo payload = e.Options.Payload as ApplicationInfo;
if (e.Options.Status == DragStatus.DropPossible)
{
box.BorderBrush = listBoxDragPossible;
}
else
{
box.BorderBrush =
new SolidColorBrush(Colors.Gray);
}
if (e.Options.Status == DragStatus.DropComplete)
{
if (!itemsSource.Contains(payload))
{
itemsSource.Add(payload);
}
}
}
void OnDropQuery(object sender, DragDropQueryEventArgs e)
{
ItemsControl box = e.Options.Destination as ItemsControl;
IList<ApplicationInfo> itemsSource = box.ItemsSource as IList<ApplicationInfo>;
ApplicationInfo payload = e.Options.Payload as ApplicationInfo;
e.QueryResult = payload !=
null && !itemsSource.Contains(payload);
}
void OnDragInfo(object sender, DragDropEventArgs e)
{
ListBoxItem listBoxItem = e.Options.Source as ListBoxItem;
ListBox box = System.Windows.Controls.ItemsControl.ItemsControlFromItemContainer(listBoxItem) as ListBox;
IList<ApplicationInfo> itemsSource = box.ItemsSource as IList<ApplicationInfo>;
ApplicationInfo payload = e.Options.Payload as ApplicationInfo;
if (e.Options.Status == DragStatus.DragComplete)
{
if (payload != null && itemsSource.Contains(payload))
{
itemsSource.Remove(payload);
}
}
}
protected virtual void OnDragQuery(object sender, DragDropQueryEventArgs e)
{
L
istBoxItem listBoxItem = e.Options.Source as ListBoxItem;
ListBox box = ItemsControl.ItemsControlFromItemContainer(listBoxItem) as ListBox;
if (e.Options.Status == DragStatus.DragQuery && box != null)
{
e.Options.Payload = box.SelectedItem;
ContentControl cue = new ContentControl();
cue.ContentTemplate =
this.Resources["ApplicationDragTemplate"] as DataTemplate;
cue.Content = box.SelectedItem;
e.Options.DragCue = cue;
e.Options.ArrowCue =
RadDragAndDropManager.GenerateArrowCue();
}
e.QueryResult =
true;
}
}
public class ApplicationInfo
{
public Double Price
{
get;
set;
}
public String IconPath
{
get;
set;
}
public String Name
{
get;
set;
}
public String Author
{
get;
set;
}
}
}
8 Answers, 1 is accepted
You need to use the Telerik.Windows.Controls.ItemsControl, not the base one. The methods you try to call are in there.
All the best,
Valentin.Stoychev
the Telerik team
Instantly find answers to your questions on the new Telerik Support Portal.
Check out the tips for optimizing your support resource searches.
Rank 1
thanks for the reply,but i am unable to give Telerik.Windows.Controls.ItemsControl as it not recognising itemscontrol in Telerik.Windows.Controls.
Hm - this is strange. Can you please double check your code. All our controls rely on it - so it is there for sure.
Have you added a reference to Telerik.Windows.Controls dll and do you have:
using Telerik.Windows.Controls;
in your class?
Let us know how it goes.
Best wishes,
Valentin.Stoychev
the Telerik team
Instantly find answers to your questions on the new Telerik Support Portal.
Check out the tips for optimizing your support resource searches.
Rank 1
i changed the code line to
ListBox
box = Telerik.Windows.Controls.ItemsControl.ItemsControlFromItemContainer(listBoxItem) as ListBox;
but it gives an error as:
Cannot convert type 'Telerik.Windows.Controls.ItemsControl' to 'System.Windows.Controls.ListBox' via a reference conversion, boxing conversion, unboxing conversion, wrapping conversion, or null type conversion C:\Documents and Settings\manas.rastogi\Desktop\Telerik Drag And Drop\Telerik Drag And Drop\Page.xaml.cs 128 27 Telerik Drag And Drop
Rank 1
i solved that error but something else is now cropping up.Can you provide me with a working sample demonstrating drag and drop the way it is shown in your demo.
Thanks
Manas
Please find attached the example from our online demo.
Be aware that you need to add "using Telerik.Windows" if you use it in thsi way:
public event EventHandler<DragDropQueryEventArgs> DragQuery
{
add
{
this.AddHandler(RadDragAndDropManager.DragQueryEvent, value);
}
remove
{
this.RemoveHandler(RadDragAndDropManager.DragQueryEvent, value);
}
}
I hope that this will help you.
Greetings,
Boryana
the Telerik team
Instantly find answers to your questions on the new Telerik Support Portal.
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Rank 1
Thanks for providing me with the sample draganddropexample.zip.But here also i had to change the following lines:
ListBoxItem
listBoxItem = e.Options.Source as ListBoxItem;
ListBox box = ItemsControl.ItemsControlFromItemContainer(listBoxItem) as ListBox;
to
Telerik.Windows.Controls.
ListBoxItem listBoxItem = e.Options.Source as Telerik.Windows.Controls.ListBoxItem;
Telerik.Windows.Controls.
ListBox box = Telerik.Windows.Controls.ItemsControl.ItemsControlFromItemContainer(listBoxItem) as Telerik.Windows.Controls.ListBox;
else it was showing an exception that 'System.Windows.Controls.ItemsControl' does not contain a definition for 'ItemsControlFromItemContainer'.Now after changing,the following variables listBoxItem,box,itemsSource turn out to be null in the method
void
OnDragInfo(object sender, DragDropEventArgs e).My exception is NullReferenceException was unhandled by UserCode.
Please help me with this.
The ItemsControlFromItemContainer() method is available in the base ItemsControl class with the release of Silverlight 3 and is missing in older versions of the runtime. From what you are saying it seems that you are developing against the Silverlight 2 runtime. Is there any specific reason why you are not working with the official version of Silverlight?
As a side note, with our latest release 2009 Q2 SP1 we officially ended the support for the now obsolete Silverlight 2 version of the runtime.
All the best,
Tihomir Petkov
the Telerik team
Instantly find answers to your questions on the new Telerik Support Portal.
Check out the tips for optimizing your support resource searches.