Невозможно запустить InvokeCommandAction

При щелчке текстового блока я хочу поднять его содержимое в моей модели представления и, если это верно, перейти на другую страницу. К сожалению для меня, событие щелчка никогда не запускает связанную команду. Ниже мой код

В xaml у меня есть такая разметка

<UserControl x:Class = "SchoolPrism.Login.Views.Login"

             xmlns = "http://schemas.microsoft.com/winfx/2006/xaml/presentation"

             xmlns:x = "http://schemas.microsoft.com/winfx/2006/xaml"

             xmlns:mc = "http://schemas.openxmlformats.org/markup-compatibility/2006"

             xmlns:i = "clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"

             xmlns:d = "http://schemas.microsoft.com/expression/blend/2008" 

             xmlns:local = "clr-namespace:SchoolPrism.Login.Views"

             xmlns:prism = "http://prismlibrary.com/"

             xmlns:constants = "clr-namespace:Infrastructure.Constants;assembly=SchoolPrismInfrastructure"

             xmlns:login = "clr-namespace:SchoolPrism.Login.ViewModel"

             mc:Ignorable = "d" 

             d:DesignHeight = "300" d:DesignWidth = "300">

    <!-- when we have a view model, bind to that instead-->
    <Grid DataContext = "{Binding login:LoginViewModel}">
        <Grid.RowDefinitions>
            <RowDefinition/>
            <RowDefinition Height = "5*"/>
        </Grid.RowDefinitions>

        <TextBlock DataContext = "{Binding}" Text = "{Binding FormResults}"></TextBlock>

        <TextBlock Text = "hi, can you see me?" x:Name = "SchoolCode" Grid.RowSpan = "2" Margin = "0,50,0,0">
            <i:Interaction.Triggers>
                <i:EventTrigger EventName = "PreviewMouseDown">

<!--tried replacing interactivity with prism here but it had no effect -->
<i:InvokeCommandAction Command = "{Binding submitForm}" CommandParameter = "{Binding Text, ElementName=SchoolCode}" ></i:InvokeCommandAction>
                </i:EventTrigger>
            </i:Interaction.Triggers>
        </TextBlock>
    </Grid>
</UserControl> 

Затем в модели представления у меня есть это

using Prism.Commands;
using Prism.Modularity;
using SchoolPrism.Modules.Login;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Input;

namespace SchoolPrism.Login.ViewModel
{
    class LoginViewModel
    {

        ICommand submitForm
        {
            get { return new DelegateCommand<string>(SubmitForm); }
        }

        public void SubmitForm(string code)
        {

            // interact with model over given code

            // if auth, get module instance and invoke the following
            new LoginModule().proceedToNext("AllTopics");

        }
    }
}

Наконец, в самом модуле у меня есть

using Microsoft.Practices.ServiceLocation;
using Microsoft.Practices.Unity;
using Prism.Commands;
using Prism.Modularity;
using Prism.Mvvm;
using Prism.Regions;
using SchoolPrism.Login.Views;
using System;
using System.Windows;
using System.Windows.Input;

namespace SchoolPrism.Modules.Login
{
    [Module(ModuleName = "LoginModule")]
    class LoginModule : BindableBase, IModule
    {

        IRegionManager _regionMan;

        // this method is called on our behalf by prism
        public void Initialize ()
        {

            _regionMan = ServiceLocator.Current.GetInstance<iregionmanager>();

        }

        public void proceedToNext (string target)
        {

            _regionMan.RequestNavigate("LoginForm", new Uri(target, UriKind.Relative)/*, (NavigationResult result) => { return code.Length > 0; }*/);
        }
        }
 }