I want to make a bigger checkbox in WPF.
I've discovered that I need to do a control template, one example of which is found here:
http://msdn.microsoft.com/en-us/library/ms752319.aspx
If I use that code the checkbox doesn't resemble the default look. All I want to do is change the Border Width & Height attributes.
I need a control template that looks exactly like the default, from there I will just change the Width and Height. Does anyone know where I can find one? Or a better approach?
How about this?
<CheckBox>
<CheckBox.LayoutTransform>
<ScaleTransform ScaleX="2" ScaleY="2" />
</CheckBox.LayoutTransform>
</CheckBox>
You can use double values for ScaleX and ScaleY if the integer values are not exactly what you want.
Here is a possible solution found on msdn:
http://social.msdn.microsoft.com/Forums/en-US/wpf/thread/98cf8a65-f4ca-4ff5-9851-c2989b91a013
The default ControlTemplates can be found on MSDN (see Default WPF Themes link).
Make sure to add the respective themes namespace to your xaml file to reference the necessary theme controls.
<theme:BulletChrome Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
RenderMouseOver="{TemplateBinding IsMouseOver}"
RenderPressed="{TemplateBinding IsPressed}"
IsChecked="{TemplateBinding IsChecked}"/>
I am not sure if you can just specify it generically, you might need to add references too.
The problem here is that you cannot really specify a border size either since the control encapsulates it.
The best solution I found is to wrap it in the ViewBox:
<Viewbox Height="46" HorizontalAlignment="Left" >
<CheckBox Content="Some Content"/>
</Viewbox>
You can use visual tree of the checkbox and when the elements you want exist, change them at runtime by explicitly setting the Width and Height. Use Peter Blois' snoop or some equivalent to see if there are named elements you can access with FindName; if not you will have to guess (e.g., some styles might have two Border elements and you must pick one) and walk the visual tree explicitly.
Keep in mind that your code should do nothing if you don't find the elements you are looking for.
Related
In our app we use 3rd party library components.
I need to change only one value in whole template. How can I archieve this without redefine template?
For example, controlTemplate:
<ControlTemplate TargetType="{x:Type Label}">
<Border x:Name="PART_MainBorder"
BorderBrush="Black"
BorderThickness="{TemplateBinding BorderThickness}">
<ContentPresenter/>
</Border>
</ControlTemplate>
I need to change PART_MainBorder.BorderBrush. How can I do this?
I have found this link, but I can't believe there is no other way to do it..
Thanks.
I'm sure there are more elegant ways to do it in XAML but to answer your question template is nothing more but a cookie cuter so you cannot just start changing properties of template objects in code behind. You can modify template controls properties via control to which the template has been applied. In case of ControlTemlate it will be templated control and for DataTemplate it will be ContentPresenter used to generate content. So let's say that you have 2 Labels to which you applied template above:
<Label Content="A" x:Name="Label1"/>
<Label Content="B" x:Name="Label2"/>
an then in the code you can change Border.BorderBrush like this:
(Label1.Template.FindName("PART_MainBorder", Label1) as Border).BorderBrush = new SolidColorBrush(Colors.Red);
(Label2.Template.FindName("PART_MainBorder", Label2) as Border).BorderBrush = new SolidColorBrush(Colors.Orange);
worth noting that 2 Labels will have different BorderBrush color
What I want to get is any way for making zoom on a collection of controls but keep the width, height and position for a subset of this controls. I have seen the question How to keep element size while WPF zoom in and out?, seems very much to what I want, but is not answered and also is not very explicit so a will improve the question.
Currently I'm using the Zoombox control that comes with the WPF Toolkit extended for .net framework 4.0, but I can change it. The structure that I have is the following:
<Border x:Name="drawRegionBorder" Grid.Column="1" Grid.Row="1" d:LayoutOverrides="Width, Height" BorderThickness="1" CornerRadius="4" BorderBrush="{StaticResource BorderBrush}" >
<xctk:Zoombox x:Name="zoomBox">
<Grid x:Name="drawRegion" Height="{Binding Height}" Width="{Binding Width}" HorizontalAlignment="Left" VerticalAlignment="Top" Background="{DynamicResource DrawBackgroundBrush}">
<Image Source="{Binding Image}" ... />
<ListBox x:Name="points" ItemsSource="{Binding Points}">
<ListBox.Template>
<ControlTemplate>
<Canvas IsItemsHost="True"/>
</ControlTemplate>
</ListBox.Template>
</ListBox>
<ListBox x:Name="paths" ItemsSource="{Binding SomePaths}">
<ListBox.Template>
<ControlTemplate>
<Canvas IsItemsHost="True"/>
</ControlTemplate>
</ListBox.Template>
</ListBox>
<!--... Others ...-->
</Grid>
</xctk:Zoombox>
</Border>
What I have here, are several list boxes, inside a grid, and the items panel for each list box is a Canvas, so each child (but the image) will be located inside a canvas and also each child will set the Canvas.X and Canvas.Y properties. So what I want, is any way of make the zoom (zoom-in or zoom-out), and keep the size of poitns (ellipsed) or paths...
Due the zoom, is a wpf's scale transformation, I suppose maybe a way for doing this when the zoom-in, make the zoom-out to the control I want to keep the size, and viceversa.
An example of the spected behavior is the blend designer, for instance when you zoom in a grid with rows and columns, the columns indicators keeps the original size, some thing like that is what I want for my points and paths.
I will appreciate any solution, maybe library, attached property, behavior or code.
Thaknks
The Blend designer uses Adorners for its manipulators. The sizes are calculated according to zoom the current zoom. If you're interested in using a similar technique, it's actually not that hard to do the calculation yourself.
You would create an adorner set to the Bounds of your control, then apply a scale factor according to the zoom in the designer. So if you zoom by 2.0, then you apply a RenderTransform of Scale 2.0 to your zoomed control, while calculating your adorner to be 2.0 of the ActualWidth and ActualHeight of the zoomed control (because those two properties do not take into account RenderTransformations). The nice thing is that since everything uses doubles, you get pixel perfect precision when doing this kind of calculation.
By using this approach, you gain the ability to zoom your main controls, while your manipulators simply scale to the zoomed controls, but maintain their control size throughout.
This tutorial is a good starting point. In the OnRender method is where you'd want to apply the scaling factor (by calculating the bounds of your adorner based on the UIElement's ActualWidth/Height, then multiplying by your scaling factor). How you apply your adorner depends a lot on application context - if you're doing a designer, then you'd want to apply the adorners in a design canvas or upon item selection.
I had made a research and found some useful things, for instace, if you are working with Adorners you can override the GetDesiredTransform in order to set what transform to do you want your adorner to do, here you can make null the transform made to your adorner. For more details see How to exclude scaleTransform from GeneralTransform in Adorner GetDesiredTransform method. In Msdn. But I think that if I want make it on controls I need to control the transform by my self.
I am developing a Silverlight 4 out of browser application using a standard ComboBox and I need to press the tab key twice to move over the control. The other controls (TextBox, RadioButton etc) in the data entry form are all behaving normally, i.e. only a single tab is required.
I created a simple sample application and found that the ComboBox was behaving correctly so there is something special about my real application that is causing the problem. I suspect the problem is due to the fact that I am using the AccentColor Theme. I've had a number of problems with these themes and have come to realise that they should be considered as samples of what is possible. Their quality is not good enough for use in a production application as this Introducing the new Silverlight 4 themes blog post suggests.
I am asking this question so that I can answer it myself to capture the solution for future reference.
The AccentColor Theme creates an implicit Style for a ComboBox which includes setting the Template property. This template uses a ToggleButton with a custom style that wraps the ContentPresenter inside a ContentControl for some reason (styling?) and by default the IsTabStop property is true. Explicitly setting this property to false restores the intuitive behaviour of a single tab to move over the control.
<ContentControl VerticalAlignment="Center" IsTabStop="False">
<ContentControl.Foreground>
<SolidColorBrush x:Name="ContentPresenterWrapperColor" Color="{StaticResource BaseColor1}" />
</ContentControl.Foreground>
<ContentPresenter x:Name="contentPresenter" ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
</ContentControl>
The standard ComboBox template does not include this ContentControl which explains the difference in behaviour. I am not familiar enough with the AccentColor theme to know if it would be better to remove the ContentControl altogether or if it is required for the custom visual styling.
FYI Silverlight Spy was a great help in tracking down the problem in the behaviour, even if it is a bit pricey imho :-)
What is the Panel.IstItemsHost attached property used for?
I see plenty of examples of people setting it on the ItemsContainer template for an ItemsControl, but the un-documentation over at MSDN does not explain why or what advantages setting property confers.
Say I have an ItemsControl. I want to use a custom panel that swoops items in and out as you scroll; its called a SwoopPanel. Now, how do I tell the ItemsControl to use my SwoopPanel to contain the templates it creates?
The quick way is to set the ItemsPanel on the ItemsControl:
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<lol:SwoopPanel />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
However, sometimes that doesn't work for you. Maybe you wish to customize how the SwoopPanel is presented in the UI, and the only way to get around this is to change the control template of the ItemsControl. Now you can add your SwoopPanel directly to the control template and, using the property, mark it as the ItemsHost that the ItemsControl will put all the templated items it creates.
<Style TargetType="ItemsControl">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ItemsControl">
<Border CornerRadius="5">
<ScrollViewer VerticalScrollBarVisibility="Hidden">
<lol:SwoopPanel IsItemsHost="True"/>
</ScrollViewer>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
Do you have to do it one way or the other? No. Is one more advantageous than the other? Well, the second way allows you more control of the UI, the first way is easier. Take your pick, really. I've never personally done it the second way, but I think there might be a couple of places where it might be useful.
More Explanation, Please!
While all of the above answers are technically correct, I feel they don't illustrate how IsItemsPanel correlates to the ControlTemplate and the presence (or absence) of an ItemsPresenter and the corresponding ItemsPanel property which it uses. This answer will attempt to shed light on those things and hopefully clarify when you should, or shouldn't use each.
ItemsControls, Panels and IsItemsHost, Oh my!
An ItemsControl is simply a control that displays a collection of items. It does this by first generating individual containers* to represent the items visually, then it hands those containers over to a specific panel to be laid out for display on screen. As items are added or removed, the ItemsControl adds or removes the corresponding containers from the panel as needed.
* Note: If an item is already an instance of the container type (as determined by the result of the IsItemItsOwnContainer override of the ItemsControl)--i.e. you add a ListBoxItem instance to the Items collection of a ListBox--that item is simply passed through as-is directly to the panel, acting as its own container.
The specific panel used for hosting and laying out the containers is the first one found in the ItemControl's control template that has its IsItemsHost property set to 'True'.
There are two ways to specify which panel that is:
By inserting an ItemsPresenter into the ControlTemplate to act as a placeholder for the panel specified by the ItemsPanel property. (This is the most common way.)
By inserting a Panel directly into the ControlTemplate and explicitly setting its IsItemsHost property to True.
But which do you use and why? Read on to find out!
ItemsPresenter - "Have It Your Way!"
In a typical ControlTemplate for an ItemsControl such as a ListBox, the template specifies an ItemsPresenter somewhere inside of it. Here's a simplified excerpt showing how it's used:
<Border x:Name="Bd"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}">
<ScrollViewer Focusable="false" Padding="{TemplateBinding Padding}">
<ItemsPresenter />
</ScrollViewer>
</Border>
As you can see, there is an ItemsPresenter specified inside of a ScrollViewer in the middle of the template. What you don't see however is an actual panel to lay out the items.
So if there's no panel defined in the template, where does it come from? That's where the ItemsPanel property comes in. As its name suggests, this property defines which panel will be used to host and lay out the items. It doesn't however say where that panel appears in the ControlTemplate.
That brings us back to the ItemsPresenter. In short, it's a placeholder that essentially says "When the ItemsPanel property is set, I'll insert that panel here and set its IsItemsHost to True automatically."
The advantage of using an ItemsPresenter in the template for your ItemsControl is that you're making it very easy for consumers of your control to replace the panel without having to completely re-template your entire control.
IsItemsHost - "My Way or the Highway!"
However, what if you don't want someone to be able to change out your panel because your control depends on some custom panel implementation and anything else will break the functionality? In that case, you don't use an ItemsPresenter in your template. You instead need to specify the exact panel you want to use.
This is where IsItemsHost property comes into play. When set on a panel in the ControlTemplate, it tells that ItemsControl to use that specific panel to host the generated containers, regardless of what ItemsPanel is set to. The ItemsPanel property is essentially ignored.
Another benefit of specifying the panel directly in the template is you can then name it and access it just like any other template part.
Here's the same example as above, but rather than an ItemsPresenter, it hard-codes a SpecializedPanel to lay out the items. We indicate that's the panel we want to use to host the items by setting its IsItemsHost property to True and finally, we give it a name so we can access it directly from code.
<Border x:Name="Bd"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}">
<ScrollViewer Focusable="false" Padding="{TemplateBinding Padding}">
<SpecializedPanel name="PART_MainPanel" IsItemsHost="True" />
</ScrollViewer>
</Border>
In this case, because the template doesn't use an ItemsPresenter and instead directly includes a panel with its IsItemsHost set to True, there is no way for the user to change out that panel short of completely replacing the entire ControlTemplate. (As mentioned before, the ItemsPanel property is ignored.)
Bringing it all home...
To recap, if you're a control author and want to give consumers of your control the flexibility to swap out the panel used to lay out your items, then define your template for your ItemsControl using an ItemsPresenter. Make sure to also set the ItemsPanel property in the template to specify a default panel.
If however, want to 'lock' which panel your control uses, then do not use an ItemsPresenter in the ControlTemplate. Instead, specify the specific panel you want to use directly in the template, then set its IsItemsHost property to True.
Note: There's technically a third scenario, which is arguably more common: You're not a control author creating something to be consumed by other users, but rather are simply re-templating an ItemsControl (like say a ListBox) for some specialized use in your own application.
In that case, since you are the ultimate consumer of the control, you most likely won't have to worry about other consumers downstream needing to change out the panel, so it's completely fine to simply specify the panel directly in your template (again, setting its IsItemsHost true) and not worry about using an ItemsPresenter and its associated ItemsPanel property as the latter, while valid, would just add unnecessary complexity without any actual benefit.
Hope this clarifies exactly what's going on.
See http://msdn.microsoft.com/en-us/library/system.windows.controls.panel.isitemshost(v=vs.90).aspx
Essentially, what this post says is that if you are replacing the ControlTemplate of a ListBox and want a new layout, set IsItemsHost=true on some panel, e.g. a StackPanel. Then any items in the ListBox will be automatically added as children of the StackPanel. If the orientation of the ListBox is Horizontal, then the ListBox will be horizontal.
The other way is to set the ItemsPanel property of the ListBox to an ItemsTemplate and in that template you have a StackPanel. In this case the ListBox items will be added to the StackPanel children just as in the first case. However, you do not need to set IsItemsHost = true, it will have absolutely no effect. This is done for you by the fact that you are setting the ItemsPanel property.
I'm trying to use a StaticResource in a ControlTemplate for a custom object, and whenever that object is rendered, the application crashes. As you can see in the code below, I define both the template and the resource in App.XAML. I've been doing a bit of searching to see if/why this isn't allowed, but have had no luck so far.
<Color x:Key="PersonBackground">#FF003B00</Color>
<ControlTemplate x:Key="PersonTemplate" TargetType="this:Person">
<Border Background="{StaticResource PersonBackground}" BorderBrush="White"
BorderThickness="2" CornerRadius="10" MinHeight="70" MinWidth="120">
...
</ControlTemplate>
If anyone could explain why this isn't allowed or what I'm doing wrong (or, best yet, a better way to do custom theming in Silverlight), I would greatly appreciate it.
Edit: I feel like I should specify that I'm mostly just interested in being able to set the color scheme in one place; the rest of the theme won't need to change as much.
Instead of Color, can you try using a SolidColorBrush
<SolidColorBrush x:Key="PersonBackground" Color="#FF003B00"/>