I have a ScrollViewer with some nested child elements like this:
<ScrollViewer x:Name="MainScrollViewer"...>
<Grid ...>
<TextBlock ... FontSize="20" ...>
<StackPanel ...>
<TextBlock ... FontSize="15" ...>
...
<TextBlock ... FontSize="15" ...>
</StackPanel ...>
</Grid>
</ScrollViewer>
Most of the TextBlocks have a FontSize set explicitly in the control.
I'm writing a Windows Universal app and so I am using the Visual State Manager to take care of different window sizes. I need to change the font size of all child elements within MainScrollViewer for one of the visual states.
I tried setting the FontSize using one of the setters for a particular visual state as such:
<Setter Target="MainScrollViewer.FontSize" Value="10">
This seems to have no effect, as it is not overriding the values. How can I override all font sizes of child elements using a VSM Setter?
If no better solution comes up you could take one TextBlock as the font size master and all other TextBlocks bind to that master. Doing so you only need to set the font size of the master in the VSM.
<TextBlock x:Name="FonSizeMaster" FontSize="20" ... />
<TextBlock FontSize="{Binding FontSize, ElementName=FonSizeMaster}" .../>
MSDN has a good example for VSM
Manages states and the logic for transitioning between states for controls.
https://msdn.microsoft.com/en-us/library/system.windows.visualstatemanager(v=vs.110).aspx
Since FontSize is an attached property the following should also work (not tested):
<ScrollViewer x:Name="MainScrollViewer" TextElement.FontSize="20" ...>
<Grid ...>
<TextBlock ... >
<StackPanel ...>
<TextBlock ... >
...
<TextBlock ... >
</StackPanel ...>
</Grid>
</ScrollViewer>
VSM:
<Setter TargetName="MainScrollViewer" Property="TextElement.FontSize" Value="10">
Related
How can I change the Background of the header of a GroupBox?
I'm trying to do that with:
<GroupBox Grid.Row="0">
<GroupBox.Header>
<Setter Property="Background" //<- no backgroundproperty
there is no Background property
You can define a Border in the Header and set the Background of it to your desired color:
<GroupBox >
<GroupBox.Header>
<Border Background="Red">
<Label Content="Hello"></Label>
</Border>
</GroupBox.Header>
</GroupBox>
You could set the Header property to any UI element including a Grid or a Border for example:
<GroupBox>
<GroupBox.Header>
<Border Background="Green">
<TextBlock Text="header..." />
</Border>
</GroupBox.Header>
<TextBlock Text="content..."></TextBlock>
</GroupBox>
Take a look at this site: Control Templates, Styles, and Triggers
this is probably more than you need, but it explains how to use a control template to modify controls in various ways. I use this particular control (with different colors) for groupboxes on one of my applications, and it has come in very handy.
simple question!
I want to present an itemscontrol inside of an expander and grid which contains a textbox. I want to do this multiple times so I wrapped it in a ControlTemplate.
<ControlTemplate x:Key="ArrayPresenter">
<Expander Template="{StaticResource ArrayTemplate}">
<Grid>
<ContentPresenter/>
<TextBlock FontWeight="Bold" Text="Empty" Margin="3" HorizontalAlignment="Center" Foreground="#66C9C9C9" FontSize="15" Visibility="{quickConverter:Binding '$P.Count == 0 ? Visibility.Visible : Visibility.Collapsed', P={Binding Array}}" />
</Grid>
</Expander>
</ControlTemplate>
This is what I want to present. Unfortunately whenever an item is added to the itemscontrol, nothing happens and it doens't display the new items!
<ContentControl Template="{StaticResource ArrayPresenter}">
<ItemsControl Style="{StaticResource ArrayItemsStyle}" Margin="5" ItemTemplate="{StaticResource StructureFieldTemplate}"/>
</ContentControl>
As mentioned in the comment you need to target type of your ControlTemplate
<ControlTemplate ... TargetType="{x:Type ContentControl}">
Without that ControlTemplate targets System.Windows.Controls.Control type and that does not have Content to present so ContentPresenter does not know what to show.
I have an ItemsControl which displays a list of messages. It's defined as ...
<ItemsControl HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
ItemsSource="{Binding Messages}" >
</ItemsControl>
I then have a DataTemplate which handles the display for each message. It's defined as...
<DataTemplate DataType="{x:Type vm:MessageViewModel}">
<Button Command="{Binding CommandOpenPage}">
<Button.Template>
<ControlTemplate>
<Border Margin="2" BorderThickness="1"
BorderBrush="{Binding Flags, Converter={StaticResource msgFlagConverter}}"
Background="{Binding Flags, Converter={StaticResource msgFlagConverter}, ConverterParameter=1}" >
<TextBlock Text="{Binding Path=Message}" Style="{StaticResource ActionItem}" TextWrapping="Wrap" />
</Border>
</ControlTemplate>
</Button.Template>
</Button>
</DataTemplate>
Everything displays OK. My problem is when the parent controls are set to Visibility=Collapsed my ItemsControl still goes through the DataTemplate and calls the converters for BorderBrush and BackgroundBrush for each MessageViewModel.
This is bothersome because when the list is very large the bindings are set and converters are executed when they shouldn't. This list is only visible when the user chooses to see it. I understood the binding engine ignores elements under a collapsed parent. Is there an exception to this rule? Or am I just missing something?
I found my problem. The above ItemsControl and DataTemplate were in a UserControl. The visibility was originally handled inside the usercontrol itself by binding the main layout grid to a visibility property. By simply setting the user controls visibility in the parent XAML all bindings started behaving as expected.
This fixes my problem but I still don't understand the difference between setting the visibility of the main layout grid vs the visibility of the usercontrol itself.
<c:ApplicationMenuView Grid.Column="1" Grid.Row="4"
HorizontalAlignment="Left" Margin="1"
VerticalAlignment="Stretch"
DataContext="{Binding Menu}"
Visibility="{Binding IsVisible, Converter={StaticResource BooleanToVisibilityConverter}}"/>
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>
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.