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silverlightpathcloningpathgeometry

How do you clone a path resource in Silverlight?


I have a resource defined in my Xaml file as follows:

 <Path x:Key="myPath"
    Data="M14.773241,18.080208 C12.373256,18.080208 10.239936,19.30687 10.239936,27.573483
    L10.239936,36.106766 C10.239936,45.440037 12.586588,46.506699 14.986573,46.506699
    C18.613216,46.506699 19.359879,42.400059 19.359879,35.3601 L19.359879,27.733482
    C19.359879,20.05353 17.386559,18.080208 14.773241,18.080208 z M14.879907,11.786915
    C17.973221,11.786915 22.293194,13.013573 24.906511,17.920212 C26.773167,21.386856
    27.519829,27.093487 27.519829,32.213455 C27.519829,34.506775 27.306496,41.706726
    24.906511,46.453365 C23.626518,49.013351 20.906536,52.799992 15.199905,52.799992
    C2.1333201,52.799992 2.1333201,37.600086 2.1333201,32.160122 C2.1333201,28.05348
    2.1333201,22.666847 4.4266391,18.453541 C5.8666301,15.840225 8.639946,11.786915
    14.879907,11.786915 z"
 />

I want to able to add multiple "instances" of this path (and several others) to a StackPanel. Of course, I can't simply add "myPath" to the panel since it's already a child of another container.

However, I can't seem to be able to clone the path either. I've tried:

Path clone = new Path() 
{
  Data = source.Data
};

But no luck...exception about value being out of expected range.

Finally, I tried digging into source.Data (a PathGeometry), but it contains no PathFigures...I have no idea why, since the Path does render if I copy it from the resource section to a panel directly.

What gives?

Thanks, Sergio


Solution

  • Put the path data in a string resource:

    <Page.Resources>
        <system:String x:Key="PathData">
        M14.773241,18.080208 C12.373256,18.080208 10.239936,19.30687  10.239936,27.573483
        L10.239936,36.106766 C10.239936,45.440037 12.586588,46.506699 14.986573,46.506699
        C18.613216,46.506699 19.359879,42.400059 19.359879,35.3601 L19.359879,27.733482
        C19.359879,20.05353 17.386559,18.080208 14.773241,18.080208 z M14.879907,11.786915
        C17.973221,11.786915 22.293194,13.013573 24.906511,17.920212 C26.773167,21.386856
        27.519829,27.093487 27.519829,32.213455 C27.519829,34.506775 27.306496,41.706726
        24.906511,46.453365 C23.626518,49.013351 20.906536,52.799992 15.199905,52.799992
        C2.1333201,52.799992 2.1333201,37.600086 2.1333201,32.160122 C2.1333201,28.05348
        2.1333201,22.666847 4.4266391,18.453541 C5.8666301,15.840225 8.639946,11.786915
        14.879907,11.786915 z
        </system:String>
    </Page.Resources>
    

    And to use it:

    <Path x:Name="Path1" Data="{StaticResource PathData}" Fill="Blue" ... />
    <Path x:Name="Path2" Data="{StaticResource PathData}" Fill="Red" ... />
    

    You'll need this in your XAML declaration:

    xmlns:system="clr-namespace:System;assembly=mscorlib"
    

    If you want to create paths programmatically using a common path string, Silverlight is missing a bit of key functionality that WPF has -- so you have to kludge it:

    string pathXaml = 
    @"<Path xmlns=""http://schemas.microsoft.com/winfx/2006/xaml/presentation""
            xmlns:x=""http://schemas.microsoft.com/winfx/2006/xaml""
            Data=""path_data_goes_here"" />";
    Path path = (Path)System.Windows.Markup.XamlReader.Load(pathXaml);