I have a WPF MVVM application with an itemscontrol. The number of horizontal child items is influenced by the itemscontrol width. There is only 1 thing i haven't solved. I'm trying to align the child elements in a way that there are always centered. I have made quick pictures in paint to demonstrate what i mean.
How it's now:
If the width further inceares then a forth item will be added horizontally. This function needs to stay.
How I would like to see it:
If there is enough room for a forth item then it needs to be added. I'm thinking that the answer could be a simple XAML property. Anybody an idea?
Put the ItemsControl in a Grid and set its HorizontalAlignment to Center:
<Grid>
<ItemsControl ItemsSource="{Binding Images}" HorizontalAlignment="Center">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel Orientation="Horizontal"/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Image Source="{Binding}" .../>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Grid>
Related
I want to show a list of thumbnails, and allow the user to choose one. A ListBox seemed an obvious choice, setting the template to include the thumbnail and description.
The following code does this correctly...
<ListBox Margin="5"
Name="BackgroundsLb">
<ListBox.ItemTemplate>
<DataTemplate>
<Border Margin="5"
BorderBrush="Black"
BorderThickness="1">
<StackPanel Margin="5">
<Image Source="{Binding Path=Data, Converter={StaticResource BytesToImageVC}}"
Width="150"
HorizontalAlignment="Center" />
<TextBlock Text="{Binding Path=Description}"
HorizontalAlignment="Center" />
</StackPanel>
</Border>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
However, this displays the thumbnails vertically, one per row, as is normal for a ListBox. Given that the thumbnails are only 150 pixels wide, I would like to show them in something more like a grid, but (ideally) in a way so that the number of columns adapts to the size of the window.
I tried replacing the ListBox with an ItemsControl, adding in the following...
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel Orientation="Vertical" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
...and it displayed exactly how I wanted it, but the ItemsControl does not allow selection, so is no use for my purpose.
Is there a way to achieve a flexible, selectable display that fills the horizontal space, and breaks onto a new row according to the size of the window?
Thanks
You can use an ItemsPanelTemplate in a ListBox just the same as you are using one in the ItemsControl. The difference I think you're seeing is that ListBox uses scroll bars by default rather than wrapping the content. Basically the content is allowed to grow forever, so you never get the wrap. Instead you get a scrollbar. The good news is you can disable this behavior. The following should give you a horizontal wrap, where new rows are created as needed.
<ListBox ScrollViewer.HorizontalScrollBarVisibility="Disabled">
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
</ListBox>
Can't find a solution to a pretty simple UI problem:
I have a model with a Images property. The Images property holds a collection of items Image.
As for now on - I have a ListBox and binding a ListBoxItem data template to Images.Image and all good. But I have each item on a new line. Not good.
What I am willing to achieve is, lets describe as, a Listbox with Horizontal items orientation and limit of items in a row. Just like Large icons view style in Windows Explorer.
Have somebody previously implemented such a solution? Any advice will be highly appreciated.
Thank you in advance.
Use a WrapPanel (or some other appropriate Panel) as the ListBox's ItemsPanel, and disable horizontal scrolling:
<ListBox ItemsSource="{Binding Images}"
ScrollViewer.HorizontalScrollBarVisibility="Disabled">
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel/>
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
<ListBox.ItemTemplate>
<DataTemplate>
<Image Source="{Binding}" Width="100" Margin="5"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
You can set the ListBox's ItemPanelTemplate to WrapPanel, like this.
I am not sure why it is always like that - but as soon as I asked, I have found an alternative solution with usage of ListView:
<ListView ItemsSource="{Binding Images}">
<ListView.ItemTemplate>
<DataTemplate>
<Image Source="{Binding Image}" />
</DataTemplate>
</ListView.ItemTemplate>
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<UniformGrid Columns="2" />
</ItemsPanelTemplate>
</ListView.ItemsPanel>
</ListView>
I would like to create a multi-column list of checkboxes, but here's the catch - as I resize the window I would like everything to scale accordingly, including text size. I've been trying to make use of a WrapPanel and ViewBox but can't get the XAML right. Are these controls the best option or should I be using a ListBox (note I don't need selection functionality or scrollbars)? Any suggestions or examples on how I could achieve this would be much appreciated. I'm using MVVM and the list will be data bound, if that makes a difference.
BTW since starting WPF I've been struggling to understand which controls size to their children and which size to their parent. Are there any good sites, cheat sheets, or whatever summarising the behaviour of each control?
If you have a variable number of child elements, you could put a UniformGrid into a ViewBox.
If the child elements have to be visualized by a DataTemplate, you would have to use an ItemsControl with the ItemsPanel property set to such a UniformGrid:
<Viewbox Stretch="Uniform">
<ItemsControl ItemsSource="{Binding Items}" Width="400" Height="200">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<UniformGrid Columns="4"/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Border Background="AliceBlue">
<CheckBox Content="{Binding Label}" IsChecked="{Binding IsChecked}"
HorizontalAlignment="Center" VerticalAlignment="Center"/>
</Border>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Viewbox>
I've been struggling a while with marquee-style image scrolling control.
At a moment, I stuck up with templated ItemsControl:
<Window.Resources>
<DataTemplate x:Key="itemsTemplate">
<Image Source="{Binding AbsolutePath}"></Image>
</DataTemplate>
</Window.Resources>
<ItemsControl ItemTemplate="{StaticResource itemsTemplate}" x:Name="ic"
ItemsSource="{Binding ElementName=mainWindow, Path=DataItems}" VirtualizingStackPanel.IsVirtualizing="True">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<VirtualizingStackPanel Orientation="Vertical" VerticalAlignment="Bottom"
VirtualizingStackPanel.IsVirtualizing="True" >
</VirtualizingStackPanel>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
</ItemsControl>
ItemsControl is bound to ObservableCollection, so I can add items at runtime. As soon as item goes off-screen it's removed from ObservableCollection.
The last thing to do is implementing custom item add behavior (smooth slide-in instead of insert-translateothers behavior).
Shall I derive from StackPanel to achieve such effect or just perform DoubleAnimation on currently adding item?
Any suggestions appreciated.
Check this out: Animate WPF Datatemplate when item added to Listbox. Will it suit your needs?
In Silverlight, I have a Vertical ListBox that has a Horizontal ListBox for each item. I want the items in the HorizontalListbox to space evenly across the width of the parent (Vertical) ListBox. How can I do this?
<ListBox x:Name="MachineListBox" Background="Green">
<ListBox.ItemTemplate>
<DataTemplate>
<ListBox ItemsSource="{Binding CoilList}" Background="Red" HorizontalAlignment="Stretch">
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel
HorizontalAlignment="Stretch" />
</ItemsPanelTemplate >
</ListBox.ItemsPanel>
<ListBox.ItemTemplate >
<DataTemplate>
<TextBlock
Text="{Binding Coil}"
HorizontalAlignment="Stretch"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
I'll take the liberty of suggesting you use a custom control of my own invention. It's called a ProportionalPanel and it does just what you need - spaces items evenly. You could use it for the ItemsPanel in the inner ListBox instead of the StackPanel. I also provide the source code, so you can tweak the logic any way you like. The relevant post on my blog is here.
I think the proportional sizing operator will do what you're looking for. Haven't tried it but it sounds like an option. Width="*" and Margin="2*".