I have the following xaml:
<DockPanel>
<DockPanel>
<CheckBox IsChecked="{Binding Path=Test}" />
<CheckBox IsChecked="{Binding Path=Test}" />
</DockPanel>
<DockPanel DockPanel.Dock="Left" Width="10" Background="Blue">
<DockPanel.Style>
<Style>
<Style.Triggers>
<DataTrigger Binding="{Binding Path=Test}" Value="True">
<Setter Property="DockPanel.Background" Value="Yellow" />
</DataTrigger>
</Style.Triggers>
</Style>
</DockPanel.Style>
</DockPanel>
</DockPanel>
Now - the 2 checkboxes link properly - checking one will check the other - but the datatrigger is not firing at all.
What am I doing wrong?
The issue here is Property Value Precedence.
You are currently setting the Background to blue directly on the DockPanel. This explicit property will override any value set by the trigger.
Instead, you must set the original "Background" as a setter in the style.
<DockPanel DockPanel.Dock="Left" Width="10">
<DockPanel.Style>
<Style>
<Setter Property="DockPanel.Background" Value="Blue" />
<Style.Triggers>
<DataTrigger Binding="{Binding Path=Test}" Value="True">
<Setter Property="DockPanel.Background" Value="Yellow" />
</DataTrigger>
</Style.Triggers>
</Style>
</DockPanel.Style>
</DockPanel></DockPanel>
Related
I have the following style:
<Style.Triggers>
<Trigger Property="IsSelected" Value="True">
<Setter Property="ContentTemplate">
<Setter.Value>
<DataTemplate>
<TextBlock x:Name="Text" Text="{Binding Name}" Margin="0, 5" FontSize="16"/>
</DataTemplate>
</Setter.Value>
</Setter>
</Trigger>
</Style.Triggers>
I want to change the foreground color of "Text" if the "ListBoxItem" is selected. I know from here: Change WPF DataTemplate for ListBox item if selected how to change the DataTemplate. but since I just want to change colors, this solution makes unnecessary duplication in codd - It would be a greater problem if my DataTemplate would be very complex and long.
How do I achieve change of a single property of an object inside the DataTemplate?
If you actually want the same item template always (whether the item is selected or not), but you want a different foreground color when the item is selected, that's easy. Don't set the ContentTemplate in a trigger, because ContentTemplate doesn't change. Just set the foreground color with a trigger. If you don't mess with the foreground color in the template, it will inherit whatever the ListBoxItem has for that property.
<Style TargetType="ListBoxItem">
<Setter Property="ContentTemplate">
<Setter.Value>
<DataTemplate>
<TextBlock
x:Name="Text"
Text="{Binding Name}"
Margin="0, 5"
FontSize="16"
/>
</DataTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsSelected" Value="True">
<Setter Property="Foreground" Value="Red" />
</Trigger>
</Style.Triggers>
</Style>
A more elaborate version of the same style:
<Style TargetType="ListBoxItem">
<Setter Property="ContentTemplate">
<Setter.Value>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Ellipse
Height="12"
Width="12"
VerticalAlignment="Center"
x:Name="Ellipse"
Fill="Yellow"
Stroke="DeepSkyBlue"
StrokeThickness="1"
/>
<TextBlock
x:Name="Text"
Text="{Binding Name}"
Margin="5,5,0,5"
FontSize="16"
/>
</StackPanel>
<DataTemplate.Triggers>
<DataTrigger
Binding="{Binding IsSelected, RelativeSource={RelativeSource AncestorType=ListBoxItem}}"
Value="True"
>
<Setter
TargetName="Ellipse"
Property="Stroke"
Value="Orange"
/>
<Setter
TargetName="Ellipse"
Property="StrokeThickness"
Value="3"
/>
</DataTrigger>
</DataTemplate.Triggers>
</DataTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsSelected" Value="True">
<Setter Property="Foreground" Value="Red" />
</Trigger>
</Style.Triggers>
</Style>
On my Grid I Have TextBlock and Button.
If Button is not visible I want my TextBlock.HorizontalAlignment to be set to Center.
If Button is visible I want my TextBlock.HorizontalAlignment to be set to Right. Here is my code:
<TextBlock Grid.Row="0" VerticalAlignment="Center" Name="myTextBlock" Text="{Binding TileTextId}" TextWrapping="Wrap" TextAlignment="Center" >
<TextBlock.Triggers>
<DataTrigger Binding="{Binding ElementName=myButton, Path=IsVisible}" Value="True">
<Setter Property="HorizontalAlignment" Value="Right" />
</DataTrigger>
</TextBlock.Triggers>
</TextBlock>
I get the error:
'HorizontalAlignment' member is not valid because it does not have a qualifying type name.
So I tried to add TextBlock.HorizontalAlignment, like this:
<TextBlock Grid.Row="0" VerticalAlignment="Center" Name="myTextBlock" Text="{Binding TileTextId}" TextWrapping="Wrap" TextAlignment="Center" >
<TextBlock.Triggers>
<DataTrigger Binding="{Binding ElementName=myButton, Path=IsVisible}" Value="True">
<Setter Property="TextBlock.HorizontalAlignment" Value="Right" />
</DataTrigger>
</TextBlock.Triggers>
</TextBlock>
I get the error:
XamlParseException
How should I do that?
Don't try to use TextBlock.Triggers, instead go for a Style with Style.Triggers.
<StackPanel>
<TextBlock Text="TextBlock Content" Margin="5">
<TextBlock.Style>
<Style TargetType="TextBlock">
<Setter Property="HorizontalAlignment" Value="Center"/>
<Style.Triggers>
<DataTrigger Binding="{Binding ElementName=myButton,Path=IsVisible}" Value="True">
<Setter Property="HorizontalAlignment" Value="Right"/>
</DataTrigger>
</Style.Triggers>
</Style>
</TextBlock.Style>
</TextBlock>
<Button x:Name="myButton" Content="Click Me!" Margin="5"/>
</StackPanel>
Take note of the documentation, as it mentions, why style triggers are needed here.
Note that the collection of triggers established on an element only
supports EventTrigger, not property triggers (Trigger). If you require
property triggers, you must place these within a style or template and
then assign that style or template to the element either directly
through the Style property, or indirectly through an implicit style
reference.
Try to do this with Style
<TextBlock Grid.Row="0" VerticalAlignment="Center" Name="myTextBlock" Text="{Binding TileTextId}" TextWrapping="Wrap" TextAlignment="Center" >
<TextBlock.Style>
<Style TargetType="TextBlock">
<Style.Triggers>
<DataTrigger Binding="{Binding ElementName=myButton, Path=IsVisible}" Value="True">
<Setter Property="HorizontalAlignment" Value="Right" />
</DataTrigger>
</Style.Triggers>
</Style>
</TextBlock.Style>
</TextBlock>
I want to have dynamic editable listbox in wpf application. I am using textbox inside listbox, and I am binding Observable collection to that listbox. Now, I want to make textbox editable on mouse click. So, user can make change to textbox and save new textbox text.
<ListBox Name="ListTwo" ItemsSource="{Binding CollectionUrl, Mode=TwoWay}" >
<ListBox.ItemTemplate>
<DataTemplate>
<TextBox Name="TextBoxList" Text="{Binding Path=urlString}" IsEnabled="False" >
</TextBox>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
You should use IsReadOnly property. In the trigger you should check IsFocused property.
In the following example, I changed foreground color to indicate which TextBox is in the edit mode.
Example:
<ListBox Name="ListTwo" ItemsSource="{Binding CollectionUrl, Mode=TwoWay}" >
<ListBox.ItemTemplate>
<DataTemplate>
<TextBox Name="TextBoxList" Text="{Binding Path=urlString}" MinWidth="100">
<TextBox.Style>
<Style TargetType="TextBox">
<Style.Triggers>
<Trigger Property="IsFocused" Value="True">
<Setter Property="Foreground" Value="Green"/>
<Setter Property="IsReadOnly" Value="False" />
</Trigger>
<Trigger Property="IsFocused" Value="False">
<Setter Property="Foreground" Value="Red"/>
<Setter Property="IsReadOnly" Value="True" />
</Trigger>
</Style.Triggers>
</Style>
</TextBox.Style>
</TextBox>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
If you want to allow users save changes after edit value in the TextBox, you can add button and show in the actual editing row:
<ListBox Name="ListTwo" ItemsSource="{Binding CollectionUrl, Mode=TwoWay}" >
<ListBox.ItemTemplate>
<DataTemplate>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="50" />
</Grid.ColumnDefinitions>
<TextBox Name="TextBoxList" Text="{Binding Path=urlString}" MinWidth="100">
<TextBox.Style>
<Style TargetType="TextBox">
<Style.Triggers>
<Trigger Property="IsFocused" Value="True">
<Setter Property="Foreground" Value="Green"/>
<Setter Property="IsReadOnly" Value="False" />
</Trigger>
<Trigger Property="IsFocused" Value="False">
<Setter Property="Foreground" Value="Red"/>
<Setter Property="IsReadOnly" Value="True" />
</Trigger>
</Style.Triggers>
</Style>
</TextBox.Style>
</TextBox>
<Button Content="Save" Grid.Column="1" Command="{Binding SaveChanges}">
<Button.Style>
<Style TargetType="Button">
<Setter Property="Visibility" Value="Collapsed" />
<Style.Triggers>
<DataTrigger Binding="{Binding ElementName=TextBoxList, Path=IsFocused}" Value="True">
<Setter Property="Visibility" Value="Visible" />
</DataTrigger>
</Style.Triggers>
</Style>
</Button.Style>
</Button>
</Grid>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
My approach to accessing the text box (which was proving a nightmare) was to use your save button approach and in the Button's Button_Click function I used sender to retrieve the Button's parent, cast to (in your case) Grid. Then you can use that to access the Grid's Children with .Children[0] being your TextBox.
Bit of a Kluge because your code has to 'know' the type of the parent and the index of the child TextBox but these will not change. If necessary the purists can iterate through the Children to identify the required child explicitly.
Hope this helps someone.
I have a view, that when loaded contains a toolbar at the top, and two regions underneath.
I am currently using a grid, so:
row 0 contains the toolbar
row 1 contains region1 and
row 2 contains region2.
The toolbar has a toggle button, which when clicked, completely hides region1, and shows region 2, and visa-versa.
What is the best way to achieve this?
I have tried binding the 2 rows heights to get altered on the toggle, but the space is not filled correctly. VerticalAlignment="Stretch" and HorizontalAlignment="Stretch" are both used.
I have also tried enabling and disabling the itemcontrol hosting the region, but that doesn't seem to work at all.
Any pointers as to what I have done are much appreciated! :)
Not sure if I fully understand what you want. Something like this?
<DockPanel>
<ToggleButton Name="viewToggle" DockPanel.Dock="Top">Toggle Region</ToggleButton>
<Grid>
<ContentControl>
<TextBlock>I'm region 1</TextBlock>
<ContentControl.Style>
<Style>
<Style.Triggers>
<DataTrigger Binding="{Binding ElementName=viewToggle, Path=IsChecked}" Value="False">
<Setter Property="ContentControl.Visibility" Value="Visible"></Setter>
</DataTrigger>
<DataTrigger Binding="{Binding ElementName=viewToggle, Path=IsChecked}" Value="True">
<Setter Property="ContentControl.Visibility" Value="Hidden"></Setter>
</DataTrigger>
</Style.Triggers>
</Style>
</ContentControl.Style>
</ContentControl>
<ContentControl>
<TextBlock>I'm region 2</TextBlock>
<ContentControl.Style>
<Style>
<Style.Triggers>
<DataTrigger Binding="{Binding ElementName=viewToggle, Path=IsChecked}" Value="True">
<Setter Property="ContentControl.Visibility" Value="Visible"></Setter>
</DataTrigger>
<DataTrigger Binding="{Binding ElementName=viewToggle, Path=IsChecked}" Value="False">
<Setter Property="ContentControl.Visibility" Value="Hidden"></Setter>
</DataTrigger>
</Style.Triggers>
</Style>
</ContentControl.Style>
</ContentControl>
</Grid>
</DockPanel>
I used for this one row that contains region1 and region2 too. region2's Visibility set to Collapsed by default, and when an event occured (a checkbox for me, databound to a bool value) i flipped the Visibility of the regions. My 'regions' contained two different layout, and i don't experienced any issue.
A quick sample code without code-behind:
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition />
</Grid.RowDefinitions>
<Grid.Resources>
<Style x:Key="showOnToggled" TargetType="GroupBox" BasedOn="{StaticResource {x:Type GroupBox}}" >
<Setter Property="Visibility" Value="Visible" />
<Style.Triggers>
<DataTrigger Binding="{Binding ElementName=toggleButton, Path=IsChecked}" Value="True" >
<Setter Property="Visibility" Value="Collapsed" />
</DataTrigger>
</Style.Triggers>
</Style>
<Style x:Key="hideOnToggled" TargetType="GroupBox" BasedOn="{StaticResource {x:Type GroupBox}}" >
<Setter Property="Visibility" Value="Collapsed" />
<Style.Triggers>
<DataTrigger Binding="{Binding ElementName=toggleButton, Path=IsChecked}" Value="True" >
<Setter Property="Visibility" Value="Visible" />
</DataTrigger>
</Style.Triggers>
</Style>
</Grid.Resources>
<ToggleButton Content="Switch Region"
Grid.Row="0"
x:Name="toggleButton" />
<GroupBox Header="Region1"
Grid.Row="1"
Style="{StaticResource showOnToggled}" >
<!-- Region1's content -->
</GroupBox>
<GroupBox Header="Region2"
Grid.Row="1"
Style="{StaticResource hideOnToggled}" >
<!-- Region2's content -->
</GroupBox>
</Grid>
If I have a set of controls within a StackPanel, is there a generic way to change the background of the stackpanel when any control within the StackPanel gains focus? (and obviously switch the background back when no control in the StackPanel has focus). The following code works for me, but it would be nice to have a generic way to accomplish this task versus having to list each control in every StackPanel in my page.
Thanks!
<StackPanel Margin="5">
<StackPanel.Style>
<Style TargetType="{x:Type StackPanel}">
<Style.Triggers>
<DataTrigger Binding="{Binding IsFocused, ElementName=chkOccupiedByMortgagor}" Value="true">
<Setter Property="Background" Value="Gray" />
<Setter Property="Opacity" Value=".5" />
</DataTrigger>
<DataTrigger Binding="{Binding IsFocused, ElementName=chkOccupiedByNewOwner}" Value="true">
<Setter Property="Background" Value="Gray" />
<Setter Property="Opacity" Value=".5" />
</DataTrigger>
</Style.Triggers>
</Style>
</StackPanel.Style>
<CheckBox Margin="2" x:Name="chkOccupiedByMortgagor">Mortgagor</CheckBox>
<CheckBox Margin="2" x:Name="chkOccupiedByNewOwner">New Owner</CheckBox>
<CheckBox Margin="2" x:Name="chkOccupiedByTenant">Tenant</CheckBox>
<CheckBox Margin="2" x:Name="chkOccupiedByUnknownOccupant">Unknown Occupant</CheckBox>
</StackPanel>
Yes. You can do that. Just use IsKeyboardFocusWithin property for the trigger, like this:
<StackPanel Margin="5">
<StackPanel.Style>
<Style TargetType="{x:Type StackPanel}">
<Style.Triggers>
<DataTrigger Binding="{Binding RelativeSource={RelativeSource Self}, Path=IsKeyboardFocusWithin}" Value="True">
<Setter Property="Background" Value="Gray" />
<Setter Property="Opacity" Value=".5" />
</DataTrigger>
</Style.Triggers>
</Style>
</StackPanel.Style>
<CheckBox Margin="2">Mortgagor</CheckBox>
<CheckBox Margin="2">New Owner</CheckBox>
<CheckBox Margin="2">Tenant</CheckBox>
<CheckBox Margin="2">Unknown Occupant</CheckBox>
</StackPanel>
Do remember though, that you need to tell the trigger to look for the property in the same element, hence, RelativeSource={RelativeSource Self}. Alternatively, you can name the stack panel and use this xaml too:
<StackPanel Margin="5" x:Name="stackPanel">
...
<DataTrigger Binding="{Binding ElementName=stackPanel, Path=IsKeyboardFocusWithin}" Value="True">
...