Is it possible to define the "presenting behavior" of a ContentPresenter so that it applies padding to its content?
Now I have a ContentPresenter and define the Margin on all UserControls that can be part of this ContentPresenter.
The downside of this, is that it calls for repeating definitions of Margins, and the UserControls are kind of dedicated to "fit" in the ContentPresenter.
E.g. XAML that contains the content presenter:
<ContentPresenter
x:Name="SettingsContentPanel"
Grid.Row="0"
Grid.Column="2"
Grid.ColumnSpan="2"
Content="{Binding ElementName=SettingsGroupSelector, Path=SelectedItem.Tag}" />
And the user controls are defined as follows:
<UserControl
<!-- left out irrelevant definitions -->
Margin="5,5,5,5">
You should be able to get the effect you're after by setting the Margin on your ContentPresenter element itself e.g:
<ContentPresenter
x:Name="SettingsContentPanel"
Grid.Row="0"
Grid.Column="2"
Grid.ColumnSpan="2"
Content="{Binding ElementName=SettingsGroupSelector, Path=SelectedItem.Tag}"
Margin="5,5,5,5" />
Also, if the Margin is the same on all sides, you could use the shorthand Margin="5".
Hope that helps =D
Related
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!
I want to add an exclamation mark Image to the left of the built-in TextBox and make it visible whenever the TextBox Validation.HasError attached property is true, otherwise hide it.
How can I use ControlTemplate to add the Image without having re-bind all the TextBox properties?
<StackPanel>
<StackPanel.Resources>
<ControlTemplate x:Key="TextBoxWithIndicator" TargetType="{x:Type TextBox}">
<StackPanel Orientation="Horizontal">
<!-- Re-bind {Binding Path=Property}, including some that I may miss -->
<TextBox Text="{TemplateBinding Text}" Width="{TemplateBinding Width}" Height="{TemplateBinding Height}"/>
<Image Source="resources/exclaim.png" Visibility="{TemplateBinding Validation.HasError}"/>
</StackPanel>
</ControlTemplate>
</StackPanel.Resources>
<TextBox Template="{StaticResource TextBoxWithIndicator}" Width="120">Happy Go Lucky</TextBox>
</StackPanel>
Note The preceding block of code represents my futile effort in WPF so far. It is probably also wrong on several counts, e.g. probably need a ValueConverter for Visibility <--> Validation.HasError; Setting Width="120" on TextBox seems to adjust the StackPanel width instead of TextBox width despite the TemplateBinding, etc.
I would suggest looking into Adorners. These are special FrameworkElements that are rendered in a special Adorner Layer on top of visual elements, and are intended to provide visual cues to the user.
The above link provides a summary of Adorners as well as an example of a Custom Adorner.
I have an ItemsControl in my user control with a scroll viewer around it for when it gets too big (Too big being content is larger than the viewable area of the UserControl). The problem is that the grid that it is all in just keeps expanding so that the scroll viewer never kicks in (unless I specify an exact height for the grid). See code below and thanks in advance.
<UserControl x:Class="BusinessObjectCreationWizard.View.TableSelectionPageView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<GroupBox FontWeight="Bold" Height="300px"
Header="Tables"
Padding="2">
<ScrollViewer>
<ItemsControl FontWeight="Normal"
ItemsSource="{Binding Path=AvailableTables}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<CheckBox Content="{Binding Path=DisplayName}"
IsChecked="{Binding Path=IsSelected}"
Margin="2,3.5" />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</ScrollViewer>
</GroupBox>
</UserControl>
This user control is loaded here
<Border Background="White" Grid.Column="1" Grid.Row="0">
<HeaderedContentControl Content="{Binding Path=CurrentPage}"
Header="{Binding Path=CurrentPage.DisplayName}" />
</Border>
I would like to not specify the height.
If you remove the Height from your GroupBox (which, as far as I understand, is what you want to do), then it will fill its container, unless there's a panel upstream that imposes its own sizing rules.
I used this simplified version of your XAML. I removed the template and the binding, and hard-coded some items, to make this stand alone; those changes won't affect the way layout is done.
<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation">
<GroupBox FontWeight="Bold" Header="Tables" Padding="2">
<ScrollViewer>
<ItemsControl FontWeight="Normal">
<TextBlock>Foo</TextBlock>
<TextBlock>Bar</TextBlock>
<TextBlock>Baz</TextBlock>
</ItemsControl>
</ScrollViewer>
</GroupBox>
</Window>
Run it, and you'll see that the content does indeed size to fit the window, and the scrollbar only enables when the window gets too small to see all three items. I believe this is what you want.
So the problem is most likely one of the parent panels, one you're not showing in your sample XAML. The problem you describe could occur if your GroupBox appears inside a StackPanel:
<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation">
<StackPanel>
<GroupBox FontWeight="Bold" Header="Tables" Padding="2">
<ScrollViewer>
<ItemsControl FontWeight="Normal">
<TextBlock>Foo</TextBlock>
<TextBlock>Bar</TextBlock>
<TextBlock>Baz</TextBlock>
</ItemsControl>
</ScrollViewer>
</GroupBox>
</StackPanel>
</Window>
Now the GroupBox appears at the top of the Window, sized to exactly fit its contents. If you shrink the Window enough, the GroupBox will be cut off -- because it's sized to fit its content, not its container. This sounds like the problem you're describing.
The reason is that StackPanel asks its children what their ideal height is (based on their content), and uses that height. Without StackPanel (or something similar), the default is to respect the control's VerticalAlignment, and if that's set to the default value of Stretch, then the control is stretched to fill its parent. This means it won't be taller than its parent, which sounds like what you want.
Solution: remove the StackPanel (or whatever else is causing you problems) and use something else. Depending on what you're trying to accomplish, you might have better luck with a DockPanel or a Grid. Hard to tell without knowing more about your layout.
Edit: Okay, it looks like the problem is indeed the HeaderedContentControl parent -- but not directly. HeaderedContentControl isn't a panel, so it doesn't do any layout of its own (and its descendant, GroupBox, doesn't have this same problem). The problem is its default template -- which includes a StackPanel. The good news is, you're free to use a different template, let's say one with a DockPanel instead:
<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<HeaderedContentControl>
<HeaderedContentControl.Style>
<Style TargetType="{x:Type HeaderedContentControl}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type HeaderedContentControl}">
<DockPanel>
<ContentPresenter ContentSource="Header" DockPanel.Dock="Top"/>
<ContentPresenter/>
</DockPanel>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</HeaderedContentControl.Style>
<GroupBox FontWeight="Bold" Header="Tables" Padding="2">
<ScrollViewer>
<ItemsControl FontWeight="Normal">
<TextBlock>Foo</TextBlock>
<TextBlock>Bar</TextBlock>
<TextBlock>Baz</TextBlock>
</ItemsControl>
</ScrollViewer>
</GroupBox>
</HeaderedContentControl>
</Window>
If you leave off the <HeaderedContentControl.Style> part, this reproduces your problem; but with the style in place, it allows the GroupBox to fill its container, so the ScrollViewer will get a scrollbar when you want it to.
If the previous answer doesn't fix the problem, you could also try binding the Width, Height of your grid to the ActualWidth, ActualHeight of your parent UserControl. Something like:
<UserControl
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
x:Class="WpfApplication.UserControl1"
x:Name="UserControl">
<Grid Height="{Binding ElementName=UserControl, Path=ActualHeight}"
Width="{Binding ElementName=UserControl, Path=ActualWidth}" />
In this case you aren't setting an explicit width and height but you are limiting the Grids width/height to the constraints of the UserControl it sits in.
I had the same issue, after reading this response I replaced all StackPanels with Grids in UserControl. It resolved the Scrollbar issue.
Try removing the grid entirely and setting the HorizontalAlignment and VerticalAlignment directly on the GroupBox. If a layoutpanel has only one child, it's often redundant... this migth be true in your case.
If that doesn't work... what's the parent of your grid control?
Why not just use a listbox instead of an itemscontrol, that has a built in scrollviewer.
They are different. If you do not want to have the items selectable, then don't use a ListBox. It is going to be heavier, and will also have the deselect a selection everytime the user clicks on an entry. Just put the ItemsControl in a ScrollViewer
I had the same problema with ListBox, it wasn't expanding and the scroll viewer didn't appear. I solved it as follows:
<UserControl x:Class="TesteView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Grid MaxHeight="710">
....
....
<StackPanel>
<ListBox MaxHeight="515"
ScrollViewer.HorizontalScrollBarVisibility="Hidden"
ScrollViewer.VerticalScrollBarVisibility="Auto"
ItemsSource="{Binding Path=Teste,Mode=TwoWay}">
....
....
</ListBox>
</StackPanel>
</Grid>
</UserControl>
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...
What is difference between a ControlTemplate and a DataTemplate in WPF?
Typically a control is rendered for its own sake, and doesn't reflect underlying data. For example, a Button wouldn't be bound to a business object - it's there purely so it can be clicked on. A ContentControl or ListBox, however, generally appear so that they can present data for the user.
A DataTemplate, therefore, is used to provide visual structure for underlying data, while a ControlTemplate has nothing to do with underlying data and simply provides visual layout for the control itself.
A ControlTemplate will generally only contain TemplateBinding expressions, binding back to the properties on the control itself, while a DataTemplate will contain standard Binding expressions, binding to the properties of its DataContext (the business/domain object or view model).
Very basically a ControlTemplate describes how to display a Control while a DataTemplate describes how to display Data.
For example:
A Label is a control and will include a ControlTemplate which says the Label should be displayed using a Border around some Content (a DataTemplate or another Control).
A Customer class is Data and will be displayed using a DataTemplate which could say to display the Customer type as a StackPanel containing two TextBlocks one showing the Name and the other displaying the phone number. It might be helpful to note that all classes are displayed using DataTemplates, you will just usually use the default template which is a TextBlock with the Text property set to the result of the Object's ToString method.
Troels Larsen has a good explanation on MSDN forum
<Window x:Class="WpfApplication7.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<Window.Resources>
<DataTemplate x:Key="ButtonContentTemplate">
<StackPanel Orientation="Horizontal">
<Grid Height="8" Width="8">
<Path HorizontalAlignment="Stretch"
Margin="0,0,1.8,1.8"
VerticalAlignment="Stretch" Stretch="Fill" Stroke="#FF000000"
Data="M0.5,5.7 L0.5,0.5 L5.7,0.5"/>
<Path HorizontalAlignment="Stretch"
Margin="2,3,0,0"
VerticalAlignment="Stretch" Stretch="Fill" Stroke="#FFFFFFFF"
Data="M3.2,7.5 L7.5,7.5 L7.5,3.5"/>
<Path HorizontalAlignment="Stretch"
Margin="1.2,1.4,0.7,0.7"
VerticalAlignment="Stretch" Fill="#FFFFFFFF" Stretch="Fill" Stroke="#FF000000"
Data="M2.5,2.5 L7.5,7.5"/>
<Path HorizontalAlignment="Stretch"
Margin="1.7,2.0,1,1"
VerticalAlignment="Stretch" Stretch="Fill" Stroke="#FF000000"
Data="M3,7.5 L7.5,7.5 L7.5,3.5"/>
<Path HorizontalAlignment="Stretch"
Margin="1,1,1,1"
VerticalAlignment="Stretch" Stretch="Fill" Stroke="#FFFFFFFF"
Data="M1.5,6.5 L1.5,1 L6.5,1.5"/>
</Grid>
<ContentPresenter Content="{Binding}"/>
</StackPanel>
</DataTemplate>
<ControlTemplate TargetType="Button" x:Key="ButtonControlTemplate">
<Grid>
<Ellipse Fill="{TemplateBinding Background}"/>
<ContentPresenter HorizontalAlignment="Center"
VerticalAlignment="Center"/>
</Grid>
</ControlTemplate>
</Window.Resources>
<StackPanel>
<Button Template="{StaticResource ButtonControlTemplate}" ContentTemplate="{StaticResource ButtonContentTemplate}" Content="1"/>
<Button Template="{StaticResource ButtonControlTemplate}" ContentTemplate="{StaticResource ButtonContentTemplate}" Content="2"/>
<Button Template="{StaticResource ButtonControlTemplate}" ContentTemplate="{StaticResource ButtonContentTemplate}" Content="3"/>
</StackPanel>
</Window>
(Templates blatently stolen from
http://msdn.microsoft.com/en-us/library/system.windows.controls.controltemplate.aspx
and
http://msdn.microsoft.com/en-us/library/system.windows.controls.contentcontrol.contenttemplate%28VS.95%29.aspx
respectively)
Anyway, the ControlTemplate decides how the Button itself looks, while
the ContentTemplate decides how the Content of the button looks. So
you could bind the content to one of you data classes and have it
present itself however you wanted it.
ControlTemplate: Represents control style.
DataTemplate: Represents data style(How would you like to show your data).
All controls are using default control template that you can override through template property.
For example
Button template is a control template.
Button content template is a data template
<Button VerticalAlignment="Top" >
<Button.Template>
<ControlTemplate >
<Grid>
<Rectangle Fill="Blue" RadiusX="20" RadiusY="20"/>
<Ellipse Fill="Red" />
<ContentPresenter Content="{Binding}">
<ContentPresenter.ContentTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" Height="50">
<TextBlock Text="Name" Margin="5"/>
<TextBox Text="{Binding UserName, Mode=TwoWay}" Margin="5" Width="100"/>
<Button Content="Show Name" Click="OnClickShowName" />
</StackPanel>
</DataTemplate>
</ContentPresenter.ContentTemplate>
</ContentPresenter>
</Grid>
</ControlTemplate>
</Button.Template>
</Button>
public String UserName
{
get { return userName; }
set
{
userName = value;
this.NotifyPropertyChanged("UserName");
}
}
ControlTemplate - Changing the appearance of element. For example Button can contain image and text
DataTemplate - Representing the underlying data using the elements.
ControlTemplate DEFINES the visual appearance, DataTemplate REPLACES the visual appearance of a data item.
Example: I want to show a button from rectangular to circle form => Control Template.
And if you have complex objects to the control, it just calls and shows ToString(), with DataTemplate you can get various members and display and change their values of the data object.
All of the above answers are great but there is a key difference that was missed. That helps make better decisions about when to use what. It is ItemTemplate property:
DataTemplate is used for elements that provide ItemTemplate property for you to replace its items' content using DataTemplates you define previously according to bound data through a selector that you provide.
But if your control does not provide this luxury for you then you still can use a ContentView that can display its content from predefined ControlTemplate. Interestingly, you can change the ControlTemplate property of your ContentView at runtime. One more thing to note that unlike controls with ItemTemplate property, you cannot have a TemplateSelector for this (ContentView) control. However, you still can create triggers to change the ControlTemplate at runtime.