I have an ItemsControl, nothing fancy:-
<ItemsControl ItemsSource="{Binding ...}"
ItemTemplate="{StaticResource ...}" />
The ItemTemplate contains the following XAML:-
<Border BorderThickness="0,0,0,1"
BorderBrush="LightGray"
Padding="0,2,0,2">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"
SharedSizeGroup="Prompt" />
<ColumnDefinition Width="Auto" />
</Grid.ColumnDefinitions>
<TextBlock Grid.Column="0"
Text="{Binding ...}" />
<NumericUpDown Grid.Column="1"
Width="75"
Text="{Binding ...}" />
</Grid>
</Border>
This produces a UI looking like this:-
However if the text in the TextBlock is very long, it pushes the NumericUpDown off the r.h. edge of the ItemsControl, e.g.:-
I was hoping that once the NumericUpDown had been "pushed up" against the r.h. edge of the ItemsControl, the TextBlock would then start getting truncated. I assume the current behaviour is due to the ItemsControl using a StackPanel as its items presenter. How can I get it to do what I want?
When you are using SharedSizeGroup with Grid.IsSharedSizeScope="True" the column's Star sizing is treated as Auto, more not official informations here.
The IsSharedSizeScope should not be used for arranging the controls described in the question. You should remove all SharedSizeGroup attributes and set the ItemsControl's HorizontalAlignment to Left.
I think that you might want to try setting the Control.HorizontalContentAlignment Property to Stretch on your ItemsControl. According to the linked page, this:
Gets or sets the horizontal alignment of the control's content.
In plain English, this means that it should set the Width of the rendered children, or items, to the same Width as the ItemsControl.
After a lot of running into dead-ends thinking I could resolve this by changing the ItemsPresenter or ItemsPanel, I ended up using a DockPanel within my ItemTemplate, instead of the grid:-
<Border BorderThickness="0,0,0,1"
BorderBrush="LightGray"
Padding="0,2,0,2">
<DockPanel LastChildFill="true">
<NumericUpDown DockPanel.Dock="Right"
Width="75"
Text="{Binding ...}" />
<TextBlock Text="{Binding ...}" />
</DockPanel>
</Border>
I'm not entirely sure why the DockPanel respects the size of the parent ItemsControl, while the Grid was happy to horizontally "overrun" off the edge. This is an aspect of WPF that I still struggle with - which controls' sizes are affected by their parent, and which are affected by their children's sizes!
Related
I have learned that if the height of a grid row, where the ScrollViewer resides, is set as Auto, the vertical scroll bar will not take effect since the actual size of the ScrollViewer can be larger than the height in sight. So in order to make the scroll bar work, I should set the height to either a fixed number or star height
However, I now have this requirement, that I have two different views reside in two grid rows, and I have a toggle button to switch between these two views: when one view is shown, the other one is hidden/disappeared. So I have defined two rows, both heights are set as Auto. And I bind the visibility of the view in each row to a boolean property from my ViewModel (one is converted from True to Visible and the other from True to Collapsed. The idea is when one view's visibility is Collapsed, the height of the grid row/view will be changed to 0 automatically.
The view show/hidden is working fine. However, in one view I have a ScrollViewer, which as I mentioned doesn't work when the row height is set as Auto. Can anybody tell me how I can fulfill such requirement while still having the ScrollViewer working automatically`? I guess I can set the height in code-behind. But since I am using MVVM, it would require extra communication/notification. Is there a more straightforward way to do that?
In MVVM, the way that worked for me was to bind the height of the ScrollViewer to the ActualHeight of the parent control (which is always of type UIElement).
ActualHeight is a read-only property which is only set after the control has been drawn onto the screen. It may change if the window is resized.
<StackPanel>
<ScrollViewer Height="{Binding Path=ActualHeight,
RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=UIElement}}">
<TextBlock Text=Hello"/>
</ScrollViewer>
</StackPanel>
But what if the parent control has an infinite height?
If the parent control has an infinite height, then we have a bigger problem. We have to keep setting the height of all parents, until we hit a control with a non-infinite height.
Snoop is absolutely invaluable for this:
If the "Height" for any XAML element is 0 or NaN, you can set it to something using one of:
Height="{Binding Path=ActualHeight, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=UIElement}}"
VerticalAlignment="Stretch"
Height="Auto"
Hint: Use VerticalAlignment="Stretch" if you are a child of a Grid with a <RowDefinition Height="*">, and the Binding RelativeSource... elsewhere if that doesn't work.
If you're interested, here is all of my previous attempts to fix this issue:
Appendix A: Previous Attempt 1
Can also use this:
Height="{Binding Path=ActualHeight, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=StackPanel}}"
Appendix B: Previous Attempt 2
Useful info: see Auto Height in combination with MaxHeight.
If nothing seems to work, it's probably because the ActualHeight of the parent is either 0 (so nothing is visible) or huge (so the scrollviewer never needs to appear). This is more of a problem if there are deeply nested grids, with a scrollviewer right at the bottom.
Use Snoop to find the ActualHeight of the parent StackPanel. In properties, filter by the word "Actual", which brings back ActualHeight and ActualWidth.
If ActualHeight is zero, give it a minimum height using MinHeight, so we can at least see something.
If ActualHeight is so huge that it goes off the edge of the screen (i.e. 16,000), give it a reasonable maximum height using MaxHeight, so the scrollbars will appear.
Once the scrollbars are appearing, then we can clean it up further:
Bind the Height of the StackPanel or Grid to the ActualHeight of the parent.
Finally, put a ScrollViewer inside this StackPanel.
Appendix C: Previous Attempt 3
It turns out that this can sometimes fail:
Height="{Binding Path=ActualHeight, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=StackPanel}}"
The reason? It the binding fails, the height will be zero and nothing will be seen. The binding can fail if we are binding to an element which is not accessible. The binding will fail if we are going up the visual tree, then down to a leaf node (e.g. up to the parent grid, then down to the ActualHeight of a row attached to that grid). This is why binding to the ActualWidth of a RowDefinition simply won't work.
Appendix D: Previous Attempt 4
I ended up getting this working by making sure that Height=Auto for all of the parent elements from us to the first <Grid> element in the UserControl.
Change Height from Auto to *, if you can.
Example:
<Window x:Class="WpfApplication3.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="200" Width="525">
<StackPanel Orientation="Horizontal" Background="LightGray">
<Grid Width="100">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<ScrollViewer VerticalScrollBarVisibility="Auto" x:Name="_scroll1">
<Border Height="300" Background="Red" />
</ScrollViewer>
<TextBlock Text="{Binding ElementName=_scroll1, Path=ActualHeight}" Grid.Row="1"/>
</Grid>
<Grid Width="100">
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<ScrollViewer VerticalScrollBarVisibility="Auto" x:Name="_scroll2">
<Border Height="300" Background="Green" />
</ScrollViewer>
<TextBlock Text="{Binding ElementName=_scroll2, Path=ActualHeight}" Grid.Row="1"/>
</Grid>
</StackPanel>
</Window>
I've had similar problem, taking me hours to figure out the solution. What solved it was using a Dockpanel as parent container instead of a StackPanel. Just specify all children to dock to top if the functionality should be similar to vertical stackpanel. Consider using LastChildFill="False" in the Dock XAML which is'n default.
So instead of:
<StackPanel Orientation="Horizontal">
<Textbox>SomeTextBox</Textbox>
<Scrollviewer/>
</StackPanel>
Try:
<DockPanel LastChildFill="False">
<Textbox DockPanel.Dock="Top">SomeTextBox</Textbox>
<Scrollviewer DockPanel.Dock="Top"/>
</DockPanel>
You can either set a fix height on your ScrollViewer but then you have to consider that the second row of your grid will have that height too since row's first child will be the ScrollViewer and row's height is auto, or you bind the height of ScrollViewer to another control in your layout. We don't know how your layout looks alike.
At the end if you don't like neither of both just set the row's height to * as swiszcz suggested or hack wpf write your own custom panel that will be able to layout everything possible in every parallel universe or something like that. :)
What I discover is that you have to put your ScrollViewer within a container that has Height=Auto or you get his parent Heigh Actual Size and apply it to that container.
In my case I have UserControl like
<Grid Margin="0,0,0,0" Padding="0,2,0,0">
<ScrollViewer Height="Auto" ZoomMode="Disabled" IsVerticalScrollChainingEnabled="True" VerticalAlignment="Top"
HorizontalScrollMode="Enabled" HorizontalScrollBarVisibility="Disabled"
VerticalScrollMode="Enabled" VerticalScrollBarVisibility="Visible">
<ListView ItemsSource="{x:Bind PersonalDB.View, Mode=OneWay}" x:Name="DeviceList"
ScrollViewer.VerticalScrollBarVisibility="Hidden"
ItemTemplate="{StaticResource ContactListViewTemplate}"
SelectionMode="Single"
ShowsScrollingPlaceholders="False"
Grid.Row="1"
Grid.ColumnSpan="2"
VerticalAlignment="Stretch"
BorderThickness="0,0,0,0"
BorderBrush="DimGray">
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<ItemsStackPanel AreStickyGroupHeadersEnabled="False" />
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.GroupStyle>
<GroupStyle>
<GroupStyle.HeaderTemplate>
<DataTemplate x:DataType="local1:GroupInfoList">
<TextBlock Text="{x:Bind Key}"
Style="{ThemeResource TitleTextBlockStyle}"/>
</DataTemplate>
</GroupStyle.HeaderTemplate>
</GroupStyle>
</ListView.GroupStyle>
</ListView>
</ScrollViewer>
</Grid>
And I add it dinamically to ContentControl which is within a Page.
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}" Margin="0,0,12,0">
<Grid.RowDefinitions>
<RowDefinition Height="70" />
<RowDefinition Height="*" MinHeight="200" />
</Grid.RowDefinitions>
<Grid Grid.Row="1" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" >
<ContentControl x:Name="UIControlContainer" />
</Grid>
</Grid>
Notice that Heigh of the Row is *
When I populate ContentControl I use this code in Loaded event
UIControlContainer.Content = new UIDeviceSelection() {
VerticalAlignment = VerticalAlignment.Stretch,
HorizontalAlignment = HorizontalAlignment.Stretch,
Height = UIControlContainer.ActualHeight,
Width = UIControlContainer.ActualWidth
};
And also when ContentControl changes its size you have to update size of the UserControl.
UIControlContainer.SizeChanged += UIControlContainer_SizeChanged;
private void UIControlContainer_SizeChanged(object sender, SizeChangedEventArgs e)
{
if (UIControlContainer.Content != null)
{
if (UIControlContainer.Content is UserControl)
{
(UIControlContainer.Content as UserControl).Height = UIControlContainer.ActualHeight;
(UIControlContainer.Content as UserControl).Width = UIControlContainer.ActualWidth;
}
}
}
Enjoy!
P.S. Acctually I did it for UWP.
I am building a ListView that needs to have five columns - the first one needs to have text that can be any length and needs to wrap whenever the window size changes (in addition to changing the row height so the wrapped text is visible) and the other four columns are a static width of 45. I've been searching for hours on this and every solution I come across either requires a static width or doesn't work.
Solutions tried:
Column widths of auto, 1*, 2*, etc. (settings ignored)
DockPanel (settings ignored)
WrapPanel (ignored)
Setting Width to RelativeSource of parent for ActualWidth (ignored)
Any ideas? It seems like a significant number of people have had this same problem, but I would highly prefer to not have to go the static width route for this column. Especially since the content just gets cut off when I do that anyway (even with height="Auto" for the row). The width of the overall window could be as small as 1024, but could also be 1600+ which is why I want dynamic sizing. That way smaller screens will have the content wrap and larger screens will just show the one line since the content fits.
Here is the XAML:
<ListView.ItemTemplate>
<DataTemplate>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition />
<ColumnDefinition Width="45" />
<ColumnDefinition Width="45" />
<ColumnDefinition Width="45" />
<ColumnDefinition Width="45" />
</Grid.ColumnDefinitions>
<!-- This is the TextBlock that needs to wrap its content (and
change the height of the row (so the full content is still
visible) to whatever the available space is, but should not
make overall ListView wider than the parent's width. -->
<TextBlock Text="{Binding Content}" Padding="20,6,6,6" />
<!-- These four blocks will have other content eventually, but only need
to be 45 wide -->
<TextBlock Text="X" Grid.Column="1" HorizontalAlignment="Center" />
<TextBlock Text="X" Grid.Column="2" HorizontalAlignment="Center" />
<TextBlock Text="X" Grid.Column="3" HorizontalAlignment="Center" />
<TextBlock Text="X" Grid.Column="4" HorizontalAlignment="Center" />
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
Not so easy...but it can be done.
I wrote a solution for you. In short, use Expression Blend to create a copy of the ListView Template and delete the ScrollViewer surrounding the ItemPresenter.
Here is a more indepth explanation:
How to have the TextBlock in a left column of a Grid in a ListView Template expand or shrink with text wrapping?
<ListView HorizontalContentAlignment="Stretch" ScrollViewer.HorizontalScrollBarVisibility="Disabled">
<ListView.ItemTemplate>
...
</ListView.ItemTemplate>
</ListView>
I'd add TextWrapping="Wrap" to the first TextBlock element.
Within a Groupbox I have a Listbox, ListboxItems are defined in the XAML as well. The Listbox is defined:
<ListBox Name="lvAvoidCountry" Margin="5,5,5,5"
Background="Transparent"
ScrollViewer.VerticalScrollBarVisibility="Visible"
ScrollViewer.HorizontalScrollBarVisibility="Disabled" >
Items are defined like this:
<ListViewItem >
<CheckBox Name="chkAlbanien" Tag="55">
<StackPanel Orientation="Horizontal">
<Image Source="images/flag_albania.png" Height="30"></Image>
<TextBlock Text="Albanien" Margin="5,0,0,0"></TextBlock>
</StackPanel>
</CheckBox>
</ListViewItem>
If I remove the Scrollviewer Settings I get horizontal scrolling and the Items are well formatted - correct width. If I use the scrollviewer settings the items get cut off so that all items are placed on the listbox. (eg. the flag is shown, the checkbox is shown but the text is just "Alba").
Thanks for any hints!
As the name implies, ScrollViewer.HorizontalScrollBarVisibility="Disabled" disables horizontal scrolling. If you do that, but your ListBoxItems are too long, they'll get cut off. The StackPanel won't grow or shrink to fit into the ListBox, and it won't "wrap" your items to fit into the ListBox if it's too narrow, even if you add TextWrapping to the TextBlock. It's very stubborn. I think your main problem is that StackPanel.
Instead of a StackPanel, try using a Grid with 2 columns defined like so:
<ListViewItem >
<CheckBox Name="chkAlbanien" Tag="55">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Image Grid.Column="0" Source="images/flag_albania.png" Height="30"/>
<TextBlock Grid.Column="1"
TextWrapping="Wrap"
Text="Albanien" Margin="5,0,0,0"/>
</Grid>
</CheckBox>
</ListViewItem>
Auto will "shrinkwrap" the image columns, and * will give the text all remaining space. Then add TextWrapping to your textblock in case it's still too long.
Edited: added more complete code example and changed my answer slightly.
if you want vertical scrolling in a listbox then don't put it in a stackpanel,instead use a grid.
Ok I got the following DataTemplate:
Style="{StaticResource LBStyle}" HorizontalContentAlignment="Stretch">
<ListBox.ItemTemplate>
<DataTemplate>
<Grid >
<Grid.ColumnDefinitions>
<ColumnDefinition Width="1*"/>
<ColumnDefinition Width="100" />
</Grid.ColumnDefinitions>
<Label Content="{Binding Name}" x:Name="txt" Grid.Column="0"></Label>
<StackPanel Orientation="Vertical" Grid.Column="1">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{z:txt text=time}" Width="50">:</TextBlock>
<TextBlock Text="{Binding Path=Value, Converter={StaticResource DecFix}}" />
</StackPanel>
<StackPanel Orientation="Horizontal" Width="50">
<TextBlock Text="Norm.">:</TextBlock>
<TextBlock Text="{Binding Path=NormaalWaarde, Converter={StaticResource DecFix}}" />
</StackPanel>
</StackPanel>
</Grid>
<DataTemplate.Triggers>
<DataTrigger Binding="{Binding IsCurrentStep}" Value="True">
<Setter TargetName="txt" Property="FontWeight" Value="Bold"/>
</DataTrigger>
</DataTemplate.Triggers>
</DataTemplate>
</ListBox.ItemTemplate>
Basically what I want is for each item to have some text on the left side, which stretches with the width of the listbox and 2 values on the right side, which stays on the right side.
I've tried this with many different kind of panels, grids etc. And they all seem to just put the values on the right side wrapped together to the text on the left side like this:
link text
(please use the link to see what I mean, I cannot post pictures yet)
If i put the same datatemplate standalone somewhere else it just does what it should do. Does anyone have a suggestion?
Edit: I put a gridsplitter between the listbox and the rest of the window and it looks like the listbox is stretching indefinately. This is how the listbox is positioned amongst other elements in my window: (the listbox is in the tagger usercontrol)
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="1*"/>
<ColumnDefinition Width="2.5*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition/>
</Grid.RowDefinitions>
<vid:TagControl x:Name="Tagger" Grid.Column="0"></vid:TagControl>
<GridSplitter ResizeDirection="Columns" Width="20" />
<vid:DShowPlayer x:Name="DShowPlayer1" Grid.Column="1"></vid:DShowPlayer>
</Grid>
The problem here is certainly not related to your DataTemplate at all, or whether or not you are using data binding. Something in the ListBox or ListBoxItem style or ControlTemplate is causing a control to have HorizontalAlignment not set to "Stretch" at some level. (Or you could be using custom Measure or Arrange code that ignores HorizontalAlignment at some level)
I would suspect your Style="{StaticResource LBStyle} is the culprit, or some other ListBox property that isn't shown.
The default ListBox style contains a template with a Border and a ScrollViewer, none of which contains a HorizontalAlignment setting
The default ListBox ItemsPanel template consists of a StackPanel, which also doesn't contain a HorizontalAlignment setting
The default ListBoxItem template contains a template with a Border and ContentPresenter. Only the Border contains a HorizontalAlignment setting, and it is set (via a style setter) to the containing ListBox's HorizontalContentAlignment, which you have set to "Stretch".
If run in isolation the code you posted works fine. Search your style (and other properties, code-behind settings, etc) for any template replacement or setting that overrides the default HorizontalAlignment handling.
If the problem isn't apparent at first, remove settings one at a time until it stops working, then look closer at what you removed.
None of the DataTemplate examples I can find state this explicitly, but it appears to be the case that DataTemplates only apply when your list items come from an ItemsSource binding. If you directly populate the Items collection, the DataTemplate isn't used.
Adding an ItemTemplate in Expression Blend, the command text reads "Generated Item Template" - which seems to mean the template is only used when the item is generated indirectly.
And every example I can find uses a data binding for the item source.
You should use Grid instead of DockPanel with 3 columns, 1st column as 1 * , 2nd and 3rd as fixed length...
This problem stems from not being able to get my TextBlock to wrap. Basically as a last-ditch attempt I am setting MaxWidth on my container grid's columns. I was surprised to find that my child label and textbox still do whatever they want (bad children, BAD) and are not limited by my grid column's MaxWidth="200".
What I'm really trying to do is let my TextBlock fill available width and wrap if necessary. So far after trying many variations of HorizontalAlignment="Stretch" on every known parent in the universe, nothing works, except setting an explicit MaxWidth="400" or whatever number on the TextBlock. This is not good because I need the TextBlock to fill available width, not be limited by some fixed number. Thanks!
<ItemsControl>
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition MaxWidth="200" SharedSizeGroup="A" />
<ColumnDefinition MaxWidth="200" SharedSizeGroup="B" />
</Grid.ColumnDefinitions>
<Label VerticalAlignment="Top" Margin="0 5 0 0" Grid.Column="0" Style="{StaticResource LabelStyle}" Width="Auto" Content="{Binding Value.Summary}" />
<TextBlock Grid.Column="1" Margin="5,8,5,8" FontWeight="Normal"
Background="AliceBlue"
Foreground="Black" Text="{Binding Value.Description}"
HorizontalAlignment="Stretch"
TextWrapping="Wrap" Height="Auto" />
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
I've tried to replicate your problem by pasting everything between your Grid elements in to Kaxaml but everything wraps as you would expect it to. (I inserted regular strings where you were doing bindings and removed the Label style).
It could be that the problem is higher up the tree.
I'd suggest pasting chunks in to Kaxaml or similar to test and see which parent breaks your UI.
I provided an answer to this question, only it was using an ListView instead of an ItemsControl but the issue is likely the same. There is probably a ScrollViewer surrounding your ItemPresenter and you need to edit a copy of the ItemsControl template.
WPF ListView TextBlock TextWrapping