Question

When I create a DataTemplate in code I am getting a error when defining the namespaces.

Below is the code I am using

 public static DataTemplate CreateDataTemplate(string bindingValue)
    {
        StringBuilder dataTemplateText = new StringBuilder();           
        dataTemplateText.Append("<DataTemplate ");
        dataTemplateText.Append("xmlns='http://schemas.microsoft.com/winfx/2006/xaml/presentation' ");
        dataTemplateText.Append("xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml' ");
        dataTemplateText.Append("xmlns:interactivity='http://schemas.microsoft.com/expression/2010/interactivity' ");

        // Custom NameSpace
        dataTemplateText.Append("xmlns:valueConverter='clr-namespace:AttachedPropertiesTest.ValueConverter;assembly=AttachedPropertiesTest'> ");
        dataTemplateText.Append("xmlns:wtf='clr-namespace:AttachedPropertiesTest.wtf;assembly=AttachedPropertiesTest'> ");
        //

        dataTemplateText.Append("<Grid>");
        dataTemplateText.Append("<Grid.Resources>");
        dataTemplateText.Append("<valueConverter:RowIndexConverter x:Key='rowIndexConverter' />");
        dataTemplateText.Append("</Grid.Resources>");
        dataTemplateText.Append("<TextBlock ");
        dataTemplateText.Append("Text = '{Binding  ");
        dataTemplateText.Append("Converter={StaticResource rowIndexConverter}, ConverterParameter=" + bindingValue + " }' >");
        dataTemplateText.Append(" <interactivity:Interaction.Triggers> ");
        dataTemplateText.Append(" <interactivity:EventTrigger EventName='MouseLeftButtonDown' > ");
        dataTemplateText.Append("      <wtf:InvokeDelegateCommandAction CommandName='CellCommand' Command='{Binding CellCommand, Source={StaticResource mainViewModel}}'  CommandParameter='{Binding Converter={StaticResource rowIndexConverter}, ConverterParameter=" + bindingValue + " }' />  ");
        dataTemplateText.Append(" </interactivity:EventTrigger> ");
        dataTemplateText.Append(" </interactivity:Interaction.Triggers> ");
        dataTemplateText.Append("</TextBlock>");
        dataTemplateText.Append("</Grid>");
        dataTemplateText.Append("</DataTemplate>");

        DataTemplate dataTemplate = (DataTemplate)XamlReader.Load(dataTemplateText.ToString());
        return dataTemplate;
    }

I get the following error:

Failed to create a
‘System.Windows.DataTemplate’ from the
text
‘xmlns:wtf=’clr-namespace:AttachedPropertiesTest.wtf;assembly=AttachedPropertiesTest’>
‘.

When I only have one namespace where I set the assembly it works.

I can get my code to work by putting all my code in one Namespace definition. I just am not a fan of this work around.

Does anyone have any idea what I am doing wrong by defining my namespaces.

Answer 1

The first custom namespace contains a closing bracket that should not be there.

dataTemplateText.Append(“xmlns:valueConverter=’clr-namespace:AttachedPropertiesTest.ValueConverter;assembly=AttachedPropertiesTest’> “);

Should probably be:

dataTemplateText.Append(“xmlns:valueConverter=’clr-namespace:AttachedPropertiesTest.ValueConverter;assembly=AttachedPropertiesTest’ “);