Opens a file selection dialog, to add documents under the current object.In the standard case this command does not need any parameters. If the dialog should allow multi file selection, the command should be used as follows:
<ToolbarItem
Name="MenuAdd"
Command="{Binding AddChildCommand}"
Text="Add">
<ToolbarItem.CommandParameter>
<classes:KeyValueList>
<classes:KeyValueParameter Key="MultipleChildItems" Value="true" />
</classes:KeyValueList>
</ToolbarItem.CommandParameter>
</ToolbarItem>
Name="MenuAdd"
Command="{Binding AddChildCommand}"
Text="Add">
<ToolbarItem.CommandParameter>
<classes:KeyValueList>
<classes:KeyValueParameter Key="MultipleChildItems" Value="true" />
</classes:KeyValueList>
</ToolbarItem.CommandParameter>
</ToolbarItem>