I have a ComboBox to let the user choose from a list, but when the list gets long enough it begins to automatically wrap around. For example, if the user scrolls far enough down they'll reach the end of the list and then find the top of the list just after a single blank row. The drop down selection list never really ends, it just keeps looping forever.
How can I remove this looping scroll feature so the user just reaches the end of list?
My code:
<ComboBox Name="listSelect" ItemsSource="{Binding DataInstance.ItemList}">
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding ItemNumber, Mode=OneWay}" />
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
Possible solution from this article: http://netitude.bc3tech.net/2013/04/12/windows-8s-combobox-and-the-carouselpanel/
Set this to your ComboBox control, this should overwrite the default panel:
<ComboBox.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Vertical" />
</ItemsPanelTemplate>
</ComboBox.ItemsPanel>
This is to edit the panel template, so your final code will be:
<ComboBox Name="listSelect" ItemsSource="{Binding DataInstance.ItemList}">
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding ItemNumber, Mode=OneWay}" />
</DataTemplate>
</ComboBox.ItemTemplate>
<ComboBox.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Vertical" />
</ItemsPanelTemplate>
</ComboBox.ItemsPanel>
</ComboBox>
Related
I need to implement the output of the product catalog.
The template is simple, the image and the name are at the bottom.
The images will go in a row and move down depending on the screen.
Previously, I created an Itemscontrol, the itemssource of which took data from the database.
I know that the option works with its own difficulties, but is it optimal or is there another way?
<ItemsControl.ItemTemplate>
<DataTemplate>
<StackPanel Margin="200">
<Image Source="{Binding Image}" Height="250"/>
<TextBlock Text="{Binding Name}" HorizontalAlignment="Center"/>
</StackPanel>
</DataTemplate>
</ItemsControl.ItemTemplate>
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
</ItemsControl>
I am using WPF ComboBox to populate a list of countries as following:
Inside ComboBox I have a VirtualizingStackPanel that contains an image and a TextBlock:
<ComboBox.ItemTemplate>
<DataTemplate>
<VirtualizingStackPanel Orientation="Horizontal">
<Image Width="30" Height="30" Margin="0" Source="{Binding code, Converter={StaticResource ImageComboBoxConverter}}" VerticalAlignment="Center"/>
<TextBlock Margin="5" Text="{Binding country_Text}"/>
</VirtualizingStackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
I am using a simple converter for DataBinding to retrieve my flag files.
The problem is, the list takes around good 3-4 seconds to populate. Can I apply some kind of buffering or caching technique for images to load faster?
You need to virtualize the ComboBox.ItemsPanel, not the .ItemTemplate. The ItemsPanel is the panel used to display all controls, while the ItemTemplate is used to display each control.
All the Virtualized StackPanel does is not render items which are not visible. Instead, it only renders visible items (plus a few extras for a scroll buffer), and will replace the data behind each item as you scroll. So using it to display each individual item is useless, and you need to instead use it as the panel to display all items.
Your code should probably look something like this :
<ComboBox ItemsSource="{Binding Countries}">
<ComboBox.ItemsPanel>
<ItemsPanelTemplate>
<VirtualizingStackPanel />
</ItemsPanelTemplate>
</ComboBox.ItemsPanel>
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Image Width="30" Height="30" Margin="0" Source="{Binding code, Converter={StaticResource ImageComboBoxConverter}}" VerticalAlignment="Center"/>
<TextBlock Margin="5" Text="{Binding country_Text}"/>
</StackPanel >
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
You may also need to add one or all of these properties to the <ComboBox> tag too.
<ComboBox VirtualizingStackPanel.IsVirtualizing="True"
VirtualizingStackPanel.VirtualizationMode="Recycling"
ScrollViewer.CanContentScroll="True" ...>
I have 3 embedded listboxes for entities: group, item, subitem.
<ListBox Name="GroupItemsListBox"
ItemSource="{Binding EntityGroups"}>
<ListBox.ItemTemplate>
<DataTemplate>
<ItemsControl Name="ItemsListBox"
ItemSource="{Binding Items}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<ItemsControl Name="SubItemsListBox"
ItemSource="{Binding SubItems}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Name} />
</DataTemplate>
</ItemsControl.ItemTemplate>
</DataTemplate>
</ItemsControl.ItemTemplate />
</ItemsControl>
</DataTemplate>
<ListBox.ItemTemplate>
</ListBox>
Also there is a case when last listbox is empty.
I want to handle SelectedItem from the lowest existing ItemControl. So i will be able to manage when the most specific object is selected.
For example when i click on ItemGroup[1].Items[0].SubItem[2] i want to get this element, but not ItemGroup[1] or ItemGroup[1].Items[0].
How can i achieve it?
Use the LongListSelector instead. This supports grouping in a much nicer way.
I just want to display Items in ListView like windows explorer (Large icons). For the same I used the below code.
<ListView Name="lstView" ItemsSource="{Binding MovieList}" >
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<!-- <VirtualizingStackPanel/> --> <!-- Working Fine -->
<StackPanel/> <!-- Items are not displayed -->
<!-- It must be wrap panel -->
<!-- OK, lets see with simple -->
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Label Content="{Binding Path}" />
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
In the above code, If I use VirtualizingStackPanel then the items are displayed fine, but one by one which I don't want. If I use StackPanel, the items are not dispalyed in screen, even the items are not added in StackPanel. I checked with Snoop tool.
I should use WrapPanel instread of StackPanel to list items, but lets see the simple StackPanel.
Why the items are not displayed in StackPanel?
Basically I want list the items like WindowExplorer large icon view.
I am using .NET 4.0
I tried same thing in my code and it's working fine. Virtualization works as long as size of the ItemsControl's viewport is restricted.
just try replacing the code given below:
<ListView ItemsSource="{Binding Movies}" Width="400" HorizontalAlignment="Left" >
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel VirtualizingPanel.IsVirtualizing="True" />
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Vertical">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Year}" FontSize="12" Margin="10,0,0,0"/>
<TextBlock Text="{Binding Name}" FontSize="12" Margin="10,0,0,0"/>
</StackPanel>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Category}" FontSize="12" Margin="10,0,0,0"/>
<TextBlock Text="{Binding Director}" FontSize="12" Margin="10,0,0,0"/>
</StackPanel>
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<ComboBox Name="cbDesignation" IsEditable="True" TextSearch.TextPath="DesignationName"
StaysOpenOnEdit="True" ItemsSource="{Binding Path=DesignationCollection,Mode=TwoWay}"
SelectedItem="{Binding Path=SelectedDesignation,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged,ValidatesOnDataErrors=True}"
VerticalAlignment="Center">
<ComboBox.ItemsPanel>
<ItemsPanelTemplate>
<VirtualizingStackPanel/>
</ItemsPanelTemplate>
</ComboBox.ItemsPanel>
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Path=DesignationName}" VerticalAlignment="Center" Grid.Column="1" Margin="5,0,0,0"/>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
If it is editable then it search but only one item I want that whrn user enter start of alphabet then it will show all the list regardin this alphabet
How about an AutoComplete TextBox instead? It also uses suggestions and does all the filtering for you. You can find one here:
http://wpfactb.codeplex.com/
(more info here: http://blogs.windowsclient.net/dragonz/archive/2010/02/23/autocomplete-textbox-control-for-wpf.aspx)