Binding as staticresource

Question

I had the following code:

    <!-- Automatically apply icons to context menus based on the header value -->
<Style x:Key="DecoratedMenuItem" TargetType="MenuItem" BasedOn="{StaticResource MenuItem}">
    <Style.Resources>
        <clr:Double x:Key="CanvasSize">16</clr:Double>
        <converters:IgnoreUnderscoresConverter x:Key="IgnoreUnderscoresConverter" />
    </Style.Resources>
    <Style.Triggers>
        <local:IconTrigger Binding="{Binding Header, RelativeSource={RelativeSource Self}, Converter={StaticResource IgnoreUnderscoresConverter}}" IconSize="{StaticResource CanvasSize}" Value="Run" Canvas="{StaticResource appbar_control_play}" />
        <local:IconTrigger Binding="{Binding Header, RelativeSource={RelativeSource Self}, Converter={StaticResource IgnoreUnderscoresConverter}}" IconSize="{StaticResource CanvasSize}" Value="Edit" Canvas="{StaticResource appbar_edit}" />
        <local:IconTrigger Binding="{Binding Header, RelativeSource={RelativeSource Self}, Converter={StaticResource IgnoreUnderscoresConverter}}" IconSize="{StaticResource CanvasSize}" Value="Delete" Canvas="{StaticResource appbar_delete}" />
        <local:IconTrigger Binding="{Binding Header, RelativeSource={RelativeSource Self}, Converter={StaticResource IgnoreUnderscoresConverter}}" IconSize="{StaticResource CanvasSize}" Value="Install" Canvas="{StaticResource appbar_social_dropbox_download}" />
        <local:IconTrigger Binding="{Binding Header, RelativeSource={RelativeSource Self}, Converter={StaticResource IgnoreUnderscoresConverter}}" IconSize="{StaticResource CanvasSize}" Value="Uninstall" Canvas="{StaticResource appbar_delete}" />
        <local:IconTrigger Binding="{Binding Header, RelativeSource={RelativeSource Self}, Converter={StaticResource IgnoreUnderscoresConverter}}" IconSize="{StaticResource CanvasSize}" Value="Advanced" Canvas="{StaticResource appbar_tardis}" />
        <local:IconTrigger Binding="{Binding Header, RelativeSource={RelativeSource Self}, Converter={StaticResource IgnoreUnderscoresConverter}}" IconSize="{StaticResource CanvasSize}" Value="Undo" Canvas="{StaticResource appbar_undo}" />
        <local:IconTrigger Binding="{Binding Header, RelativeSource={RelativeSource Self}, Converter={StaticResource IgnoreUnderscoresConverter}}" IconSize="{StaticResource CanvasSize}" Value="Redo" Canvas="{StaticResource appbar_redo}" />
        <local:IconTrigger Binding="{Binding Header, RelativeSource={RelativeSource Self}, Converter={StaticResource IgnoreUnderscoresConverter}}" IconSize="{StaticResource CanvasSize}" Value="Exit" Canvas="{StaticResource appbar_close}" />
        <local:IconTrigger Binding="{Binding Header, RelativeSource={RelativeSource Self}, Converter={StaticResource IgnoreUnderscoresConverter}}" IconSize="{StaticResource CanvasSize}" Value="Close" Canvas="{StaticResource appbar_close}" />
        <local:IconTrigger Binding="{Binding Header, RelativeSource={RelativeSource Self}, Converter={StaticResource IgnoreUnderscoresConverter}}" IconSize="{StaticResource CanvasSize}" Value="Copy" Canvas="{StaticResource appbar_page_copy}" />
        <local:IconTrigger Binding="{Binding Header, RelativeSource={RelativeSource Self}, Converter={StaticResource IgnoreUnderscoresConverter}}" IconSize="{StaticResource CanvasSize}" Value="Cut" Canvas="{StaticResource appbar_scissor}" />
        <local:IconTrigger Binding="{Binding Header, RelativeSource={RelativeSource Self}, Converter={StaticResource IgnoreUnderscoresConverter}}" IconSize="{StaticResource CanvasSize}" Value="Paste" Canvas="{StaticResource appbar_clipboard_paste}" />
    </Style.Triggers>
</Style>

And in an effort to reduce some of the copy and paste from the bindings, I tried creating a common binding as a static resource in the resource dictionary:

    <!-- Automatically apply icons to context menus based on the header value -->
<Style x:Key="DecoratedMenuItem" TargetType="MenuItem" BasedOn="{StaticResource MenuItem}">
    <Style.Resources>
        <clr:Double x:Key="CanvasSize">16</clr:Double>
        <converters:IgnoreUnderscoresConverter x:Key="IgnoreUnderscoresConverter" />
        <Binding x:Key="HeaderBinding"  Path="Header" RelativeSource="{RelativeSource Self}" Converter="{StaticResource IgnoreUnderscoresConverter}" />
    </Style.Resources>
    <Style.Triggers>
        <local:IconTrigger Binding="{StaticResource HeaderBinding}" IconSize="{StaticResource CanvasSize}" Value="Run" Canvas="{StaticResource appbar_control_play}" />
        <local:IconTrigger Binding="{StaticResource HeaderBinding}" IconSize="{StaticResource CanvasSize}" Value="Edit" Canvas="{StaticResource appbar_edit}" />
        <local:IconTrigger Binding="{StaticResource HeaderBinding}" IconSize="{StaticResource CanvasSize}" Value="Delete" Canvas="{StaticResource appbar_delete}" />
        <local:IconTrigger Binding="{StaticResource HeaderBinding}" IconSize="{StaticResource CanvasSize}" Value="Install" Canvas="{StaticResource appbar_social_dropbox_download}" />
        <local:IconTrigger Binding="{StaticResource HeaderBinding}" IconSize="{StaticResource CanvasSize}" Value="Uninstall" Canvas="{StaticResource appbar_delete}" />
        <local:IconTrigger Binding="{StaticResource HeaderBinding}" IconSize="{StaticResource CanvasSize}" Value="Advanced" Canvas="{StaticResource appbar_tardis}" />
        <local:IconTrigger Binding="{StaticResource HeaderBinding}" IconSize="{StaticResource CanvasSize}" Value="Undo" Canvas="{StaticResource appbar_undo}" />
        <local:IconTrigger Binding="{StaticResource HeaderBinding}" IconSize="{StaticResource CanvasSize}" Value="Redo" Canvas="{StaticResource appbar_redo}" />
        <local:IconTrigger Binding="{StaticResource HeaderBinding}" IconSize="{StaticResource CanvasSize}" Value="Exit" Canvas="{StaticResource appbar_close}" />
        <local:IconTrigger Binding="{StaticResource HeaderBinding}" IconSize="{StaticResource CanvasSize}" Value="Close" Canvas="{StaticResource appbar_close}" />
        <local:IconTrigger Binding="{StaticResource HeaderBinding}" IconSize="{StaticResource CanvasSize}" Value="Copy" Canvas="{StaticResource appbar_page_copy}" />
        <local:IconTrigger Binding="{StaticResource HeaderBinding}" IconSize="{StaticResource CanvasSize}" Value="Cut" Canvas="{StaticResource appbar_scissor}" />
        <local:IconTrigger Binding="{StaticResource HeaderBinding}" IconSize="{StaticResource CanvasSize}" Value="Paste" Canvas="{StaticResource appbar_clipboard_paste}" />
    </Style.Triggers>
</Style>

But my program threw up the following exception: A 'Binding' cannot be used within a 'ResourceDictionary' collection. A 'Binding' can only be set on a DependencyProperty of a DependencyObject.

Is there a WPF/MVVM accepted way of reducing this kind of bloat (and the chance of an error arising due to copy/paste)?

Marcin Iwanowski Marcin Iwanowski · Accepted Answer · 2016-02-29T17:36:26

I think that the best option is to rewrite your IconTrigger class. It should store collection of values and canvas, so you can write something like this:

    <local:IconTrigger Binding="{Binding Header, RelativeSource={RelativeSource Self}, Converter={StaticResource IgnoreUnderscoresConverter}}"  IconSize="{StaticResource CanvasSize}"> 
        <local:IconTriggerValue Value="Run" Canvas="{StaticResource appbar_control_play}" />
        <local:IconTriggerValue Value="Edit" Canvas="{StaticResource appbar_edit}" />
        <local:IconTriggerValue Value="Delete" Canvas="{StaticResource appbar_delete}" />
        <local:IconTriggerValue Value="Install" Canvas="{StaticResource appbar_social_dropbox_download}" />
        <local:IconTriggerValue Value="Uninstall" Canvas="{StaticResource appbar_delete}" />
        <local:IconTriggerValue Value="Advanced" Canvas="{StaticResource appbar_tardis}" />
        <local:IconTriggerValue Value="Undo" Canvas="{StaticResource appbar_undo}" />
        <local:IconTriggerValue Value="Redo" Canvas="{StaticResource appbar_redo}" />
        <local:IconTriggerValue Value="Exit" Canvas="{StaticResource appbar_close}" />
        <local:IconTriggerValue Value="Close" Canvas="{StaticResource appbar_close}" />
        <local:IconTriggerValue Value="Copy" Canvas="{StaticResource appbar_page_copy}" />
        <local:IconTriggerValue Value="Cut" Canvas="{StaticResource appbar_scissor}" />
        <local:IconTriggerValue Value="Paste" Canvas="{StaticResource appbar_clipboard_paste}" />
    </local:IconTrigger>

Binding as staticresource

1 Answers