User Controls Wrapped inside a panel MVVM - wpf

I am new to WPF/Xaml and searched for this issue I am facing but found it tough. Requesting some help on this.
I need to display usercontrols (DATABOUND) (horizontally) inside a panel/listview so that they wrap when the width of listview/panel is met, with a vertical scroll bar autoshown (as in figure).
so far I have this code.
<ListView Grid.Row="3"
ItemsSource="{Binding Controls}"
VerticalAlignment="Bottom" Background="{x:Null}" BorderBrush="{x:Null}"
>
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" Margin="0,0,0,10"></StackPanel>
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.ItemContainerStyle>
<Style TargetType="ListViewItem">
<Setter Property="VerticalContentAlignment" Value="Bottom"/>
<Setter Property="Focusable" Value="False" />
</Style>
</ListView.ItemContainerStyle>
<!--<ListView.ItemTemplate>
<DataTemplate>
<ContentControl Content="{Binding}" VerticalContentAlignment="Bottom"/>
</DataTemplate>
</ListView.ItemTemplate>-->
</ListView>
I have even tried the below code. Yes, it wraps but no scrollbar appears!
<ItemsControl Grid.Row="3"
Width="100" Height="200"
ItemsSource="{Binding Controls}"
VerticalAlignment="Bottom" Background="{x:Null}" BorderBrush="{x:Null}"
>
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel Orientation="Horizontal" Margin="0,0,0,10"></WrapPanel>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
</ItemsControl>
Note: I am okay with any control that makes this happens. Not necessarily be a listview.

To wrap items you need to set ItemsPanel to WrapPanel, like in second example, but you may need to disable horizontal scrolling on ListView:
<ListView ScrollViewer.HorizontalScrollBarVisibility="Disabled" .../>
also, if you want to use ItemsControl then ScrollViewer is not part of default Template, like for ListView, so you'll need to wrap in in ScrollViewer
<ScrollViewer Grid.Row="3">
<ItemsControl ...>
<!-- .... -->
</ItemsControl>
</ScrollViewer>
and don't forget to move Grid.Row="3" from ItemsControl definition to ScrollViewer

You were close :-)
Put your listview with a view panel that is a wrapanel inside your scrollviewer.
<ScrollViewer>
<ItemsSource="{Binding Controls}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel></WrapPanel>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
</ItemsControl>
</ScrollViewer>

You are using Wrap panel so you need to specify the width it supposed to take... since wrappanel is inside a items host control wrap panel itself cannot calculate the width.It will try to take all the width with respective to Orientation (in your case its horizontal)
Here is the sample code with list box as items host... in this code i have binded the wrappanel width to the actual width of the list box so that it will never take more width than the list box and also i disabled the horizontal scrolling which you don't need for horizontal orientation and vertical wrapping
Note: Make sure to change item template before using following code and it will work with all items hosts like ListView, ItemsControl...
<ListBox Width="500" Height="500" Name="listbox" ScrollViewer.HorizontalScrollBarVisibility="Disabled">
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel Orientation="Horizontal" Width="{Binding ActualWidth,ElementName=listbox}"></WrapPanel>
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
<ListBox.ItemTemplate>
<DataTemplate>
<Grid Height="100" Width="100">
<TextBlock Text="{Binding}" VerticalAlignment="Center" HorizontalAlignment="Center"/>
</Grid>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
For ItemsControl
<ItemsControl Grid.Row="3"
Width="100" Height="200"
ItemsSource="{Binding Controls}"
VerticalAlignment="Bottom" Background="{x:Null}" BorderBrush="{x:Null}"
Name="listbox"
>
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel IsItemsHost="True" Orientation="Horizontal" Width="{Binding ActualWidth,ElementName=listbox}"></WrapPanel>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.Template>
<ControlTemplate>
<ScrollViewer x:Name="ScrollViewer" Padding="{TemplateBinding Padding}">
<ItemsPresenter />
</ScrollViewer>
</ControlTemplate>
</ItemsControl.Template>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid Height="30" Width="30">
<TextBlock Text="{Binding}" VerticalAlignment="Center" HorizontalAlignment="Center"/>
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>

Related

WPF ItemControl Virtualization, Items Visibility Issue

I have an ItemControl that is virtualized and work perfectly. But when I change visibility of items from Visible to Collapsed and vice versa, it takes too long to rerender itemControl items.
<ItemsControl ItemsSource="{Binding Persons}" Grid.Row="1" VirtualizingStackPanel.IsVirtualizing="True" VirtualizingPanel.ScrollUnit="Pixel" ScrollViewer.CanContentScroll="True" Margin="0,1,0,0">
<ItemsControl.Template>
<ControlTemplate TargetType="{x:Type ItemsControl}">
<ScrollViewer CanContentScroll="True">
<ItemsPresenter/>
</ScrollViewer>
</ControlTemplate>
</ItemsControl.Template>
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<VirtualizingStackPanel Orientation="Vertical" IsItemsHost="True"/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid Height="40" Style="{StaticResource RowGridStyle}" Visibility="{Binding VisibilityProperty}">
<!--Some UI Content-->
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
this XAML is work fine when i change ItemsSource (Persons) properties. Even if I change 1000 persons name, the UI changes fast.
BUT when the VisibilityProperty of 100 persons changes, the UI rerender too long.
Any helps ?

Listview virtualization fails when applying a Data Template

I can get a large amount of items to display within a Listview.
However, when I apply a DataTemplate, the listsview does not display any items.
This works:
<ListView x:Name="ContactList" ItemsSource="{Binding SelectedCategory.Contacts}"
Height="425"
Width="425"
Margin="58,175,0,0" Canvas.ZIndex="99"
Background="Transparent" Foreground="#FF333747"
VerticalAlignment="Top" HorizontalAlignment="Left">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<VirtualizingStackPanel />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.Template>
<ControlTemplate TargetType="ItemsControl">
<Border>
<ScrollViewer>
<ItemsPresenter/>
</ScrollViewer>
</Border>
</ControlTemplate>
</ItemsControl.Template>
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBlock Text="Hello Wworld" />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ListView>
This doesn't:
<ListView x:Name="ContactList" ItemsSource="{Binding SelectedCategory.Contacts}"
Height="425"
Width="425"
Margin="58,175,0,0" Canvas.ZIndex="99"
Background="Transparent" Foreground="#FF333747"
VerticalAlignment="Top" HorizontalAlignment="Left">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<VirtualizingStackPanel />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.Template>
<ControlTemplate TargetType="ItemsControl">
<Border>
<ScrollViewer>
<ItemsPresenter/>
</ScrollViewer>
</Border>
</ControlTemplate>
</ItemsControl.Template>
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding DisplayName}" />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ListView>
It appears that displaying listview items using a data template fails once a binding is applied.
How can I resolve this?
My list was displaying several items that had empty strings.
As a result of this list being sorted in ascending order, the items that displayed empty text showed up at the beginning of the list while the other items did exist but were not within the scrollviewer's viewport.
As a result I did this:
foreach (var contact in phoneContacts)
{
if (string.IsNullOrWhiteSpace(contact.DisplayName))
{
continue;
}
.
.
.
}

Scrolling of a listbox inside another listbox

I have a listbox (with normal vertical orientation), each element of which is a listbox with horizontal orientation.
I want to have a ScrollBar inside of internal listbox. So, my problem is how to set width of internal listbox according to real current width of external.
My current code is:
<Window.Resources>
<HierarchicalDataTemplate x:Key="ItemTemplateSchedule">
<ListBox>
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
<ListBoxItem>My-Very-Long-Item-Nimber-1___</ListBoxItem>
<ListBoxItem>My-Very-Long-Item-Nimber-2___</ListBoxItem>
<ListBoxItem>My-Very-Long-Item-Nimber-3___</ListBoxItem>
<ListBoxItem>My-Very-Long-Item-Nimber-4___</ListBoxItem>
<ListBoxItem>My-Very-Long-Item-Nimber-5___</ListBoxItem>
</ListBox>
</HierarchicalDataTemplate>
</Window.Resources>
<Grid>
<ListBox ItemTemplate="{StaticResource ItemTemplateSchedule}" >
>
</ListBox>
</Grid>
Current screenshot:
.
UPD1
Ok, answer to my question is setting of width for internal listbox, thanks to #sa_ddam213:
Width="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType=ListBox}, Path=ActualWidth}"
Now I want add some new control in each row of external listbox:
<HierarchicalDataTemplate x:Key="ItemTemplateSchedule">
<StackPanel Orientation="Horizontal" Width="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType=ListBox}, Path=ActualWidth}">
<TextBlock Text="This is Text in a TextBlock"/>
<ListBox >
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
<ListBoxItem>My-Very-Long-Item-Number-1___</ListBoxItem>
<ListBoxItem>My-Very-Long-Item-Number-2___</ListBoxItem>
<ListBoxItem>My-Very-Long-Item-Number-3___</ListBoxItem>
<ListBoxItem>My-Very-Long-Item-Number-4___</ListBoxItem>
<ListBoxItem>My-Very-Long-Item-Number-5___</ListBoxItem>
</ListBox>
</StackPanel>
</HierarchicalDataTemplate>
And it doesn't work now! Is it possible to solve this problem? Current screenshot:
You can use a FindAncestor to bind to the parent ListBox ActualWidth
Example:
<Window.Resources>
<HierarchicalDataTemplate x:Key="ItemTemplateSchedule">
<ListBox Width="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType=ListBox}, Path=ActualWidth}" >
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
<ListBoxItem>My-Very-Long-Item-Nimber-1___</ListBoxItem>
<ListBoxItem>My-Very-Long-Item-Nimber-2___</ListBoxItem>
<ListBoxItem>My-Very-Long-Item-Nimber-3___</ListBoxItem>
<ListBoxItem>My-Very-Long-Item-Nimber-4___</ListBoxItem>
<ListBoxItem>My-Very-Long-Item-Nimber-5___</ListBoxItem>
</ListBox>
</HierarchicalDataTemplate>
</Window.Resources>
Result:

Resizeable WPF ListBox / ItemsControl items

I would like to have GridSplitter-like functionality in a WPF ListBox (or ItemsControl). The following code doesn't work but demonstrates what I want to achieve:
<ListBox ItemsSource="{Binding MyCollection}">
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal"/>
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
<ListBox.ItemTemplate>
<DataTemplate>
<Grid>
<TextBlock Text="{Binding MyTextProperty}" Margin="0,0,10,0"/>
<GridSplitter
Width="5"
Background="Red"
HorizontalAlignment="Right"
ResizeBehavior="CurrentAndNext"/>
</Grid>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
Does anyone have an idea on how to implement this?
Why not use ListView GridView? GridView supports resizing columns.

Silverlight ItemsControl vertical scrollbar, using a wrappanel as ControlTemplate

I have a collection of elements, each one with a name and a subcollection of image blobs.
I want to display an Accordion, with each item representing each of the MainElements. inside each element, I display the images in the subcollecion of said MainElement.
The Accordion gets resized by the user, so I use a wrappanel for presenting the images. When the accordion is wide enough, the images reorder themselves fitting as many as posible in each row.
the problem comes when the wrappanel only displays one image per row (because there's no space enough for more), the image list continues, but I can't see all the images, because they don't fit inside the control's height.
I need a vertical scrollbar to be displayed inside the AccordionItem so I can scroll down the image list.
So, here's my code:
<layoutToolkit:Accordion Width="Auto" Height="Auto" ItemsSource="{Binding MainElementCollection}">
<layoutToolkit:Accordion.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding MainElementName}" />
</DataTemplate>
</layoutToolkit:Accordion.ItemTemplate>
<layoutToolkit:Accordion.ContentTemplate>
<DataTemplate>
<ItemsControl ItemsSource="{Binding SubElementCollection}" ScrollViewer.VerticalScrollBarVisibility="Auto" >
<ItemsControl.Template>
<ControlTemplate>
<controlsToolkit:WrapPanel />
</ControlTemplate>
</ItemsControl.Template>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid>
<Image Margin="2" Width="150" Source="{Binding PreviewImage, Converter={StaticResource ImageConverter}}" />
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</DataTemplate>
</layoutToolkit:Accordion.ContentTemplate>
</layoutToolkit:Accordion>
http://www.silverlightshow.net/tips/How-to-add-scrollbars-to-ItemsControl.aspx suggests that I should surround my wrappanel with a scrollviewer, like this
<ItemsControl.Template>
<ControlTemplate>
<scrollviewer>
<controlsToolkit:WrapPanel />
</scrollviewer>
</ControlTemplate>
</ItemsControl.Template>
But then my wrappanel gets really small and I can only see a small vertical scrollbar
Any ideas?
Thanks a lot.
Edit: I figured thatthe wrappanel loses its width when used in the controltemplate
It should be used as follows:
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<controlsToolkit:WrapPanel ScrollViewer.VerticalScrollBarVisibility="Visible" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
Anyway, I tried adding the ScrollViewer.VerticalScrollBarVisibility="Visible" line but I'm stuck again.
Edited again:
Now my wrappanel looks like this:
<ItemsControl ItemsSource="{Binding StageVideos}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<controlsToolkit:WrapPanel />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Image Margin="2" Width="150" Cursor="Hand" MouseLeftButtonDown="videoPreview_MouseLeftButtonDown" Tag="{Binding}" Source="{Binding PreviewImage, Converter={StaticResource ImageConverter}}" />
</DataTemplate>
</ItemsControl.ItemTemplate>
<ItemsControl.Template>
<ControlTemplate>
<ScrollViewer VerticalScrollBarVisibility="Visible">
<ItemsPresenter />
</ScrollViewer>
</ControlTemplate>
</ItemsControl.Template>
</ItemsControl>
I'm using a wrappanel as the items panel, and I'm using the ControlTemplate to surround the presenter with a scrollviewer. Still, no luck :/
It's working perfectly. i had two different Accordions on the same page, and I was checking my code changes in the one whose code I wasn't touching.
Sometimes you need to pause, go for a walk and then look at the whole screen.
The right code is the last one:
<ItemsControl ItemsSource="{Binding StageVideos}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<controlsToolkit:WrapPanel />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Image Margin="2" Width="150" Cursor="Hand" MouseLeftButtonDown="videoPreview_MouseLeftButtonDown" Tag="{Binding}" Source="{Binding PreviewImage, Converter={StaticResource ImageConverter}}" />
</DataTemplate>
</ItemsControl.ItemTemplate>
<ItemsControl.Template>
<ControlTemplate>
<ScrollViewer VerticalScrollBarVisibility="Visible">
<ItemsPresenter />
</ScrollViewer>
</ControlTemplate>
</ItemsControl.Template>
</ItemsControl>

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