Develop Reference

How to style ItemsPresenter in WPF?

I have a project which contains a timeline view (this one). I need the background of this timeline view to be transparent (as I am rendering other objects/controls behind it). There is an element which is coloured Opaque, so I need to change this to transparent.
If I inspect the elements in the view during debug execution, I can see that the element which needs to be changed is an ItemsPresenter (see image below). The ItemsPresenter contains a StackPanel, and when changing the colour of this stackpanel by editing its properties in the live visual tree, the issue is resolved.
...How do I add a style for the ItemsPresenter control that can be used either globally or specifically by the timeline, changing the background of the stackpanel it contains? Are you able to provide an example?
Many thanks for your help.

The ItemsControl has an ItemsPanelTemplate that you can set the Background property of:
<ItemsControl ...>
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Background="Gray"/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
...
</ItemsControl>

How can I design a region settings like this in WPF

Till now I have a combo-box control which displays all the available region language in the UI as a combo-box items.
its in WPF and MVVM
<ComboBox
x:Name="cbLanguage"
Grid.Row="1"
Height="30"
Width="200"
HorizontalAlignment="Center"
VerticalAlignment="Top"
ItemsSource="{Binding LocalLanguages,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
SelectedIndex="0">
But I saw this window and thought this looks much more legant and modern.
Can I do similar kind of window in WPF.
I tried to change the Combobox with list-box, List-view but no result.
Any help if there is any control in WPF which can do this.
This solves many problem specially if the combo box have more than 10 items user has to scroll through the all and then select the last index. But in this way user can select any locals as all are displayed in the UI. Even user can have the option to display alphabetically.

arraging items in 3 columns can be achieved by using UniformGrid as ItemsPanel
<ComboBox.ItemsPanel>
<ItemsPanelTemplate >
<UniformGrid Columns="3"/>
</ItemsPanelTemplate>
</ComboBox.ItemsPanel>
modify ItemTemplate to change items apperance and have green color for selected item
i think it is necessary to modify ComboBox template to have custom header and footer in a dropDown (Edit Template-Edit a Copy in Visual Studio designer)

In WPF combobox is basically a Popup when the toggle button is pressed.
You could implement your own popup or you could have a look at the template of the ComboBox. Here is a link to ComboBox template

Add textblock to bottom of listview

I need to put a textblock containing result count information at the bottom of a databound listview. It needs to be within the listview's scrollbars but not be affected by the scrollbars (it must always sit at the bottom of the listview).
Because a listview cannot contain a textblock directly I am achieving this by adding some padding at the bottom of the listview and using a negative margin to make a separate textblock appear as though it is part of the listview. The issue with this is that when the listview's horizontal scrollbar is displayed it covers the textblock. I could add code to figure out if the scrollviewer is displayed and then adjust the margins/paddings accordingly BUT at this stage it sounds like a hacky solution.
Is there a better way to achieve this?

Instead of using a ListView.. you can do something like this:
<ScrollViewer>
<StackPanel>
<ItemsControl ItemsSource="{Binding MyCollection}" />
<TextBlock />
</StackPanel>
</ScrollViewer>

Thumbnail Control

Hi all i need to design a control that has a thumbnail views of picture.it can take list of pictures.i need it in wpf.is there any pre existed library of control?
if no how can i design i have no idea
Thanks
was looking something like http://www.codeproject.com/KB/graphics/crystal_image_grid_viewer.aspx?msg=3290254

If you have a list of pictures you can place a panel (StackPanel, WrapPanel, etc., depends on the behaviour you want) inside a ListBox. Set the panel to be the items host, and set the list of pictures as the ItemsSource. Something like this:
<ListBox x:Name="_listBox" >
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel Orientation="Horizontal" IsItemsHost="true" />
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
</ListBox>
and then in the code behind set _listBox.ItemsSource to your list of pictures.
(or you can have your list of pictures in an ObservableCollection and bind the ListBox to it)
EDIT: as for the thumbnails you can use something like:
BitmapImage Picture = new BitmapImage();
Picture.BeginInit();
Picture.UriSource = ... // your picture
Picture.DecodePixelWidth = ... //how big you want your pic
Picture.EndInit();

do you want to show all the images of the list at the same time? I believe you can use the grid and put a picture control in any cell of the grid, you can start with this approach, post your results and ask more specific questions once you have it at least partly done.

Listbox where items have more than one selectable region

I'm not sure about the best way to implement this in WPF, so I'll state my problem first.
I have a collection of frames. Each frame has two images. Let's say I have 10 frames giving a total of 20 images. I want to show the images at the bottom of the screen organized like a film strip - 2 rows and 10 columns. When the user clicks on one of this images or uses the arrow, it should become selected and the selected image information will be used somewhere else in the application.
I've implemented it as a ListBox with ItemsSource bound to my viewmodel's Frames collection (an observablecollection). In the DataTemplate of the ListBox, I've created a grid with two rows, each one containing a Image control. The one on row 0 is bound to TopImage (a property of my Frame class) and the bottom one is bound to BottomImage.
All this work, but the problem is that when I use the arrows, the whole frame (item) gets selected. How do I select each image in the datatemplate individually?
OR
Is there a better way to implement this>

You have two problems:
You want to separate the selectability of the upper and lower images in a frame
You want the arrow keys to be able to navigate images in two dimensions
If you did not have the arrow key requirement, then you could solve the first problem by nesting ListBox objects inside a parent ItemsControl. But then the arrows only do the right thing within a ListBox. To address that requires a different approach.
Here is a 2x2 grid data-bound to a four-element collection of images. Here we use the little-used UniformGrid to cause the collection to wrap after so many columns. Since we're using an ItemsControl, we lose automatic selection support but we get it back by making the Image control the content of a Button.
<Grid>
<Grid.Resources>
<x:Array x:Type="sys:String" x:Key="sampleData">
<sys:String>http://thecybershadow.net/misc/stackoverflow.png</sys:String>
<sys:String>http://thecybershadow.net/misc/sourceforge.png</sys:String>
<sys:String>http://thecybershadow.net/misc/stackoverflow.png</sys:String>
<sys:String>http://thecybershadow.net/misc/sourceforge.png</sys:String>
</x:Array>
</Grid.Resources>
<ItemsControl ItemsSource="{StaticResource sampleData}" Focusable="False">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<UniformGrid Columns="2"/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Button>
<Button.Content>
<Image Source="{Binding}"/>
</Button.Content>
</Button>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Grid>
The net effect is a 2x2 grid of images that you can freely arrow around between. You can use styling to make the button aspect less button-like without losing focusability. So bind all twenty images to this view, first the top ten and then the bottom ten. You can also bind the column count from the same data source.