I have a panel with a custom ListView. The ListView's items contains a GroupBox. The GroupBox contains a ListView. This ListView's items contains a GroupBox and so on.
All of the controls above have custom templates and styles
There are ToggleButtons in the Controls VisualTree lowest nodes.
When these buttons are checked I need to disable all the panel except of the button was clicked.
I would like to avoid event chaining through the parents in viewModel classes.
I'm using mvvm pattern and I would like to solve it in the xaml side if its possible.
EDIT: Here is a screenshot and the Pick button should disable the panel
Any suggestions are warmly welcomed.
you need to implement the relative source binding something like below.
IsEnabled="{Binding RelativeSource={RelativeSource AncestorType={x:Type Window}},Path=IsEnabled}"
Just have a read-only property in your ViewModel that is the negation of the property that your ToggleButton is bound to.
ViewModel:
private Boolean mSourceIsPicked;
public Boolean SourceIsPicked
{
get { return mSourceIsPicked; }
set
{
SetProperty("SourceIsPicked", ref mSourceIsPicked, value);
NotifyPropertyChanged("IsSourceChangeable");
}
}
public Boolean IsSourceChangeable
{
get { return ! this.SourceIsPicked; }
}
Then, in your View, just bind the IsEnabled property of the other controls to that new property.
<ComboBox ItemsSource="{Binding SourceTypes}"
IsEnabled={Binding IsSourceChangeable}" />
The advantage of binding to a property is that you can add/remove controls in your view and just bind to this property without changing additional XAML. You can also change the behavior of any control by not binding to this property.
If you really want a XAML-only solution, you can name each of the controls in the panel, and use a DataTrigger using TargetName on the "SourceIsPicked" property to disable the others:
<ComboBox x:Name="cboSourceTypes" ... />
<ComboBox x:Name="cboSourceNames" ... />
<ToggleButton>
<ToggleButton.Style>
<Style TargetType="{x:Type ToggleButton}">
<Style.Triggers>
<DataTrigger Binding="{Binding SourceIsPicked}" Value="True">
<Setter TargetName="cboSourceTypes"
Property="IsEnabled"
Value="False" />
<Setter TargetName="cboSourceNames"
Property="IsEnabled"
Value="False" />
</DataTrigger>
</Style.Triggers>
</Style>
</ToggleButton.Style>
</ToggleButton>
Note that this is all freehand, so you may need to adjust it a bit, but it gives you the idea.
Related
I wanted to make it happened to change property in ViewModel using Trigger tag in xaml.
The code I made was like this.
<Grid x:Name="LogoGrid">
<Grid.Style>
<Style TargetType="Grid">
<Setter Property="Height" Value="{Binding LogoHeight, Mode=TwoWay}"/>
<Style.Triggers>
<DataTrigger Binding="{Binding RelativeSource={RelativeSource AncestorType=Grid}, Path=ActualHeight, Converter={StaticResource ImageHeight}}" Value="False">
<Setter Property="Height" Value="150"/>
</DataTrigger>
</Style.Triggers>
</Style>
</Grid.Style>
<Image Source="/Resources/Logo/Logo.png" Style="{StaticResource GameWindowLogoStyle}"/>
</Grid>
I bound data to LogoHeight property in ViewModel and I wanted to set this property to 150 when parents grid is big enough to show Logo Image.
It works fine in the UI. but it didn't change LogoHeight property.
It is the same things keep happening when I use animation with Storyboard tag.
Is it normal things that propery can't be changed by Trigger tag or animation in the Storyboard tag.
Please tell me the way if there is a way to change property in Trigger tag or Storyboard tag.
Thank you.
A Setter in a Style cannot set the property of a view model. It can only set a property of the element to which the Style is being applied, i.e. the Grid in this case.
You may be able to work around this by using a Storyboard that animates the source property:
Setting a ViewModel boolean property inside a storyboard
I have an object in ViewModel whose properties are displayed by a datatemplate. The screen also has a button toggling the IsEditing flag in ViewModel, which should make the object properties editable, like the following:
Name should change from TextBlock to TextBox;
Color should change from colored rectangle to ComboBox with color options;
Category should change from TextBlock to ComboBox;
I know how to implement this with two completely independent DataTemplates, using a Style and a DataTrigger to toggle between them:
<ContentControl Content="{Binding FancyObject}">
<ContentControl.Style>
<Style TargetType="ContentControl">
<Setter Property="ContentTemplate" Value="{StaticResource DisplayTemplate}"/>
<Style.Triggers>
<DataTrigger Binding="{Binding DataContext.IsEditing, ElementName=UserControl}" Value="True">
<Setter Property="ContentTemplate" Value="{StaticResource EditTemplate}"/>
</DataTrigger>
</Style.Triggers>
</Style>
</ContentControl.Style>
</ContentControl>
And currently the DisplayTemplate is like this:
<DataTemplate x:Key="DisplayTemplate" DataType="my:FancyObject">
<Border>
<DockPanel DataContext="{Binding Metadata}">
<Border>
<TextBlock Text="{Binding Name}"/>
</Border>
<DataGrid
AutoGenerateColumns="False"
ItemsSource="{Binding FancyObjectCollection}">
<DataGrid.Columns>
<!-- Text and Template columns -->
</DataGrid.Columns>
</DataGrid>
</DockPanel>
</Border>
</DataTemplate>
The problem is: using two independent but similar templates would mean a duplication of layout, since only some fields would change, but the overall structure is the same.
Another option I imagine is to use a single template defined inside the Style, and use the Trigger to change the fields individually, but I don't know how to do it, or even if it is possible at all.
You can use one template.
In the template add both TextBlock and TextBox, same for all your other controls on the original template.
Bind the controls visibility to bool to visibility converter. (Or use triggers) Only one set of your control will be seen each time (based on IsEditing flag)
The ControlTemplate is only used upon generating the UI Elements. If you change the template AFTER generating the items, the generated items will not change.
You can also not use a trigger to change a TextBox to a TextBlock and vice versa.
Your only option is indeed to mirror the layout twice and hide/display it via the data bound property.
my treeview is populated with textblock items.
If a user clicks on a textblock, i want to set a property in my model called "isSelected".
But : the textblock have no Property IsSelected.
How can i Implement this ?
Derive from textblock and add a Property ?
You have to use the TreeViewItem.IsSelected property. You will have to specify the custom style for all items of the tree view.
<TreeView>
<TreeView.Resources>
<Style TargetType="{x:Type TreeViewItem}">
<Setter Property="IsSelected" Value="{Binding IsSelected}"/>
</Style>
</TreeView.Resources>
</TreeView>
I have the problem that parts of the TreeView Controltemplate need to change depending on the state of the bound (ItemsSource) ViewModels. For example the little expander icon needs to be exchanged with a different drawing based on each items ViewModel state. Additonally based on the state of each ViewModel the child items need to be arranged horizontally instead of the default vertically.
It sounds like you have to customize ItemsContainerStyle, not ControlTemplate. For example, if you want to mark TreeViewItem as selected whenever underlying ViewModel is selected, you can use the following style:
<TreeView ItemsSource="{Binding ...}
...>
<TreeView.ItemContainerStyle>
<Style TargetType="{x:Type TreeViewItem}">
<!-- IsSelected is a property on ViewModel item -->
<Setter Property="IsSelected" Value="{Binding IsSelected}"/>
<Setter .../>
</Style>
</TreeView.ItemContainerStyle>
</TreeView>
If Binding doesn't suit you, you can use Converters, Triggers in Style or ControlTemplate. Furthermore, you can also use triggers in DataTemplates.
PS: Wrote the code from head. May have a typo.
There is a relatively simple thing I'm trying to achieve but I'm unsure how to do it. Basically, I have a CLR class as follows:
class SomeClass
{
public SomeEnum Status;
}
public enum SomeEnum { One, Two, Three };
I've got a DataGrid that I'm binding an ObservableCollection<SomeClass> programmatically through the code-behind. In this DataGrid I have a DataGridTemplateColumn containing two buttons, as follows:
<toolkit:DataGridTemplateColumn Header="Actions">
<toolkit:DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Button Content="ActionOne" />
<Button Content="ActionTwo" />
</StackPanel>
</DataTemplate>
</toolkit:DataGridTemplateColumn.CellTemplate>
</toolkit:DataGridTemplateColumn>
What I want to do is bind the IsEnabled property of these buttons to a comparison based on the value of {Binding Path=Status}. For example, in pseudocode:
ActionOne.IsEnabled = BoundValue.Status != SomeEnum.Two
ActionTwo.IsEnabled = BoundValue.Status == SomeEnum.One || BoundValue.Status == SomeEnum.Two
Is there anyway to do this in XAML? The alternative would be just to write a value converter for each button, but since the content and other details of the button may vary, too, I don't want to end up writing like 6 value converters.
Cheers!
Why not expose additional Properties in SomeClass that performs the comparison logic?
ex:
public bool ActionOneEnabled
{
get { return Status != SomeEnum.Two; }
}
Then you can easily bind the Button's IsEnabled to the appropriate Property.
Don't forget to include an OnPropertyChanged("ActionOneEnabled") in your setter for Status - so that when your Status changes your Properties based on Status are re-evaluated.
You could do this using a DataTrigger in conjunction with a Converter like below. However, Bryan's solution has the benefit of not using multiple converters and it looks like that was one of your concerns so his answer might be better for your scenario.
<Button>
....
<Button.Style>
<Style TargetType="{x:Type Button}">
<Setter Property="IsEnabled" Value="False" />
<Style.Triggers>
<DataTrigger Binding="{Binding Path=Status, Converter={StaticResource yourConverter}}" Value="True">
<Setter Property="IsEnabled" Value="True" />
</DataTrigger>
</Style.Triggers>
</Style>
</Button.Style>
Another option would be to not use the DataTrigger and add the binding directly in the IsEnabled property:
<Button
IsEnabled="{Binding Path=Status, Converter={StaticResource yourConverter}}"
...
/>