I have views that may or may not be created in xaml based on a boolean condition in codebehind or a viewmodel.
I'd like to do something like:
<AlwaysVisibleView />
<IfShowSometimesViewBindingOrVariableOrSomething>
<SometimesView AProperty="something"/>
</IfShowSometimesViewBindingOrVariableOrSomething>
I'd like to implement this avoiding codebehind and other such trickery as much as possible, at the last ideally I don't want the view to be instantiated.
Dynamic creation of views can sometimes get a little tricky. Plus they tend to mess up how XAML renders things.
Can you just bind the visibility of the "Sometimes visible view" to a property? You can run that through a Boolean to visibility convertor and just have the code behind toggle the bool to show/hide.
Example thread
You can work with ContentControl and Style.Triggers to change content and visibility based on a property (example: bool ShowMe):
<ContentControl>
<ContentControl.Style>
<Style TargetType="ContentControl">
<Setter Property="Content" Value="{x:Null}"/>
<Setter Property="Visibility" Value="Collapsed"/>
<Style.Triggers>
<DataTrigger Binding="{Binding ShowMe}" Value="True">
<Setter Property="Content">
<Setter.Value>
<SometimesView AProperty="something"/>
</Setter.Value>
</Setter>
<Setter Property="Visibility" Value="Visible"/>
</DataTrigger>
</Style.Triggers>
</Style>
</ContentControl.Style>
</ContentControl>
Related
I don't understand why WPF allows me to write both
<Grid>
<Grid.Triggers>
<DataTrigger Binding="{Binding HasNeverBeenSeen}" Value="true">
<Setter Property="Background" Value="Red"/>
</DataTrigger>
</Grid.Triggers>
</Grid>
and
<Grid>
<Grid.Style>
<Style TargetType="{x:Type Grid}">
<Style.Triggers>
<DataTrigger Binding="{Binding HasNeverBeenSeen}" Value="true">
<Setter Property="Background" Value="Red"/>
</DataTrigger>
</Style.Triggers>
</Style>
</Grid.Style>
</Grid>
but only the second seems to work. Why is there a Triggers tag to Grid element if we must use a Style?
Thanks
Short answer to your question is because this is how it is designed by WPF team.
FrameworkElement.Triggers can only have EventTriggers although property is collection of TriggerBase. It's also clearly stated on MSDN page:
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.
I have this named style
<Style x:Key="validationSupport" TargetType="{x:Type Control}">
<Setter Property="Margin" Value="5,2,14,2" />
...OMISSIS...
<Style.Triggers>
...OMISSIS...
<DataTrigger Binding="{Binding DataContext.ActiveWorkspace.Editable, RelativeSource={RelativeSource AncestorType=Window}}" Value="False">
<Setter Property="IsEnabled" Value="False" />
</DataTrigger>
</Style.Triggers>
</Style>
I use it extensively for TextBoxes, ComboBoxes, DatePickers etc, so I used as TargetType a super class for all these elements, Control.
Now I would like to differentiate the setter inside the dataTrigger using specific properties that 'Control' doesn't have. It seems I have to create different styles with different names,each for every targetType I want to differentiate, but that way I have to change the style name inside all elements which use it. Is there a smarter way to achieve that goal ? I don't want want to go and modify every xaml file I have.
Update after first answer
I have tried to put the following setters inside the datatrigger:
<Setter Property="Background" Value="#FFECECF8" />
<Setter Property="CheckBox.IsEnabled" Value="False" />
<Setter Property="DatePicker.IsEnabled" Value="False" />
<Setter Property="ComboBox.IsEnabled" Value="False" />
<Setter Property="TextBox.IsReadOnly" Value="True" />
Unfortunately the tests gave odd results. The IsEnabled property is set for TextBoxes too despite the prefix should limit its application to CheckBoxes, DatePickers and ComboBoxes.
My final need was to make some control contents unchangeable avoiding the difficult to read colors associated with disabled controls. From previous researches I understood that changing the colors for a 'disabled' control is not an easy task and involves the redefinition of the control template. So I thought to apply a combination of IsReadOnly and Background, but it is not applicable for the above problem. In fact CheckBoxes, DatePickers and ComboBoxes can only be made unchangeable using the IsEnabled property.
Am I missing something ?
There is a way, but I have to warn you - this is far from best-practice and should be avoided
WPF allows you to use desired type as a prefix for the property. That way, if you apply the style to a control that doesn't inherit from the prefixed type - the setter is ignored.
<Style x:Key="validationSupport" TargetType="{x:Type Control}">
<Setter Property="Margin" Value="5,2,14,2" />
...OMISSIS...
<Style.Triggers>
...OMISSIS...
<DataTrigger Binding="{Binding DataContext.ActiveWorkspace.Editable, RelativeSource={RelativeSource AncestorType=Window}}" Value="False">
<Setter Property="IsEnabled" Value="False" />
<Setter Property="Button.Background" Value="Red" />
</DataTrigger>
</Style.Triggers>
</Style>
[Test this extensively, since I suspect that it might create memory leaks.]
I'm creating a radiobutton style. The RadioButton has a Border which hosts a ContentControl. The ContentControl has its Content property set to a Path (FemaleVector) declared in a separate ResourceDictionary. How can I change the Fill property of the path when the radiobutton IsChecked? Below is what I have so far. I am able to change the background property of the border but setting the Foreground property of the ContentControl does not change the colour of the path. (Didn't think that would work.)
<Style x:Key="Female" TargetType="{x:Type RadioButton}">
<Setter Property="Margin" Value="0,0,5,0"/>
<Setter Property="Cursor" Value="Hand"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type RadioButton}">
<Border x:Name="border" Padding="7,3,7,3" Width="35" Height="35" BorderBrush="#8CD567DC" Background="#00D567DC" CornerRadius="5" BorderThickness="0.8">
<ContentControl x:Name="content" Content="{DynamicResource FemaleVector}"/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter Property="Background" TargetName="border" Value="#8CD567DC"/>
<Setter Property="Foreground" TargetName="content" Value="Blue"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
I don't like having the long Data property of paths in my Styles, so I have moved them into a separate ResourceDictionary. Should I just put the Path back into my Style instead of keeping it in a separate ResourceDictionary?
Edit: similar questions are here and here.
If the style is not reused somewhere, I would personally keep it in local style resources section. That way you see bigger picture. Otherwise it would be wise to keep it in ResourceDictionary :)
Either way you should be able to change Fill property with:
<Setter Property="Content.Fill" TargetName="content" Value="Blue"/>
If this is not working, I advise few ways more:
You can use Trigger.EnterActions<> in Xaml. Perhaps setting property through animation will have better effect? ControlTemplate triggers with setters are sometimes way limiting.
There's also relative binding. But you gotta be careful with that. (If you pla to make it reusable)
In your FemaleVector style, you can bind Fill against ContentControl Foreground. Look for RelativeBinding in Google.
And then there's property inheritance. If you set Fill color in FemaleVector, you need to do it with style. Such as:
<Style>
<Setter Property="Fill" Value="BLACK" />
</Style>
you can later set ContentControls Style and add trigger there, like:
<ContentControl.Style>
<Style>
<Style.Triggers>
<DataTrigger Binding={Binding IsChecked, RelativeSource={RelativeSource AncestorType=RadioButto}} Value=TRUE>
<Setter Property="Path.Fill" Value="BLACK" />
</DataTrigger>
I have an very, very huge application in WPF with a Ribbon in it. The ribbon contain a bunch of RibbonControls, each binded to a different command. On every control, we put a ToolTip. We overrided these ToolTip templates to use a control of our own, which gives more information. We could call il a superToolTip.
The override of the tooltip templates is working just fine. Now we want to unify the way the tooltips are showing. What I mean is we want the same initialShowDelay, ShowDuration, etc., for every single tooltips in the application (there are tooltips elsewhere than in the ribbon, which use the same home made control that the ones of the ribbon). So, I binded the ToolTipService.InitialShowDelay, ToolTipService.BetweenShowDelay, ToolTipService.ShowDuration properties to global constants in the application.
InitialShowDelay :
The property InitialShowDelay is working just fine for almost every control in the application... The only one not working is RibbonSplitButton, which keep the default value of 400...
BetweenShowDelay :
The property BetweenShowDelay is working just fine when the tooltip is on a ListBoxItem... but not working in the Ribbon nor in a complex control of our own (a Property Grid).
These properties are set in the control on which the tooltip is set, and not on the tooltip themselves.
I honestly have absolutely no idead why it is behaving this way... Anyone has any idea on what could cause this or how to solve it?
If you need more information, do not hesitate to ask, i really am desperate about this.
Thank you very much!
The problem was that the condition for BetweenShowDelay wasn't respected, you need to have a value set for the property "ToolTip", in this case you were using a template, so the value was at null. You can resolve it this way :
<Style x:Key="{x:Type ToolTip}" TargetType="ToolTip">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ToolTip">
<Utils:ToolTipControl DataContext="{Binding ToolTipInfo}"/>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
and then place the dummy in the specified button :
<!-- RibbonButton -->
<Style TargetType="{x:Type ribbon:RibbonButton}" BasedOn="{StaticResource RibbonControlStyle}" >
<Style.Triggers>
<DataTrigger Value="true" >
<DataTrigger.Binding>
<Binding Converter="{StaticResource IsBoundConverter}" />
</DataTrigger.Binding>
<Setter Property="Command" Value="{Binding}" />
<Setter Property="ribbon:RibbonControlService.Label" Value="{Binding Name}" />
<Setter Property="ribbon:RibbonControlService.SmallImageSource" Value="{Binding Icon}" />
<Setter Property="ribbon:RibbonControlService.LargeImageSource" Value="{Binding LargeIcon}" />
<Setter Property="Visibility" Value="{Binding Visibility}" />
<Setter Property="ToolTip" Value="dummy"/> <!-- Use dummy value to force tooltip to show and to Bind the tooltip-->
</DataTrigger>
<DataTrigger Value="false" >
<DataTrigger.Binding>
<Binding Converter="{StaticResource IsBoundConverter}" />
</DataTrigger.Binding>
<Setter Property="Background" Value="#FF900000" />
</DataTrigger>
</Style.Triggers>
</Style>
That way the dummy value will be override.
:D
Here is some code showing how I implemented my ToolTips
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:ribbon="http://schemas.microsoft.com/winfx/2006/xaml/presentation/ribbon"
...>
...
<!-- Ribbon Tooltips Style -->
<Style TargetType="ribbon:RibbonToolTip">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate>
<Utils:ToolTipControl DataContext="{Binding ToolTipInfo}"/>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
...
<!-- RibbonControl -->
<Style x:Key="RibbonControlStyle">
<Setter Property="ribbon:RibbonControlService.ToolTipTitle" Value="dummy" /><!-- Use dummy value to force tooltip to show -->
<Setter Property="ToolTipService.InitialShowDelay" Value="{x:Static Utils:ToolTipViewModel.ToolTipInitialDelay}"/>
<Setter Property="ToolTipService.ShowDuration" Value="{x:Static Utils:ToolTipViewModel.ToolTipShowDuration}"/>
<Setter Property="ToolTipService.BetweenShowDelay" Value="{x:Static Utils:ToolTipViewModel.ToolTipBetweenShowDelay}"/>
<!-- This style is used to select the "Editors" tab when opening Editor without a world, and to select the "Home" tab otherwise -->
<Style.Triggers>
<DataTrigger Binding="{Binding IsWorldLoaded, Source={x:Static ViewModels:ViewportSettingsViewModel.Instance}}" Value="false">
<Setter Property="ribbon:Ribbon.SelectedIndex" Value="2"/>
</DataTrigger>
<DataTrigger Binding="{Binding IsWorldLoaded, Source={x:Static ViewModels:ViewportSettingsViewModel.Instance}}" Value="true">
<Setter Property="ribbon:Ribbon.SelectedIndex" Value="0"/>
</DataTrigger>
</Style.Triggers>
</Style>
Also, for the splitbutton problem it was that the tooltipservice werent set for the child of the splitbutton ( the two parts) wich are named PART_HeaderButton and PART_ToggleButton. So even if you create your own style it will be override by the style of the ribbonsplit button ( see this link for the splitbutton.xaml file :
https://wpfcontrolextension.svn.codeplex.com/svn/trunk/Common/RibbonControlsLibrary/v3.5/Themes/Generic.xaml
So to bypass this overriding problem ( because we don't have access to the part directly we have to go via code. Im my case, I overrided the RibbonSplitButton class and the OnLoadTemplate method. That way with getchild we can access the property of the part and change them.
public partial class DuniaRibbonSplitButton : RibbonSplitButton
{
public DuniaRibbonSplitButton()
{
InitializeComponent();
}
public override void OnApplyTemplate()
{
base.OnApplyTemplate();
var HeaderButton = base.GetTemplateChild("PART_HeaderButton");
var ToggleButton = base.GetTemplateChild("PART_ToggleButton");
OverrideAttributes(HeaderButton as Control);
OverrideAttributes(ToggleButton as Control);
}
private void OverrideAttributes(Control control)
{
control.ToolTip = "Dummy";
ToolTipService.SetInitialShowDelay(control, ToolTipViewModel.ToolTipInitialDelay);
ToolTipService.SetShowDuration(control, ToolTipViewModel.ToolTipShowDuration);
ToolTipService.SetBetweenShowDelay(control, ToolTipViewModel.ToolTipBetweenShowDelay);
}
}
I have a style on my datagrid to disable a DataGridRow based on a property binding. This makes the row unselectable, which is what I want. However, I am still able to select the disabled rows using at least 2 other ways. The first is if I use a dragging motion between two enabled rows that surround the disabled row. The second is if I click on the "select all" button on the top left of the datagrid. Is there a way to make specific rows completely unselectable?
This is what I currently have:
<DataGrid.RowStyle>
<Style TargetType="{x:Type DataGridRow}">
<Style.Triggers>
<DataTrigger Binding="{Binding DisableMe}" Value="True">
<Setter Property="IsEnabled" Value="False" />
</DataTrigger>
</Style.Triggers>
</Style>
</DataGrid.RowStyle>
What about using the SelectionChanged event to undo the selection? I really don't think there is a straightforward way to it, anyway.
You could also change the row style so it appears unselected even if it IS selected, and filter it out the selection through code...
I just stumbled upon this thread with the same problem, and I want to point out that you can simply set enabled to false.
I don't think of any proper solution to this question. But as a workaround you can bind 'IsHitTestVisible' property of DataGrid to 'IsEnabled'.
<DataGrid.RowStyle>
<Style TargetType="{x:Type DataGridRow}">
<Setter Property="IsEnabled" Value="True" />
<Setter Property="IsHitTestVisible" Value="{Binding RelativeSource={RelativeSource Self},Path=IsEnabled}"/>
<Style.Triggers>
<DataTrigger Binding="{Binding DisableMe}" Value="True">
<Setter Property="IsEnabled" Value="False" />
</DataTrigger>
</Style.Triggers>
</Style>
</DataGrid.RowStyle>