Solved: MVC4 ASP.NET IRepository problem

Hi,

I'm using MVC4 and having real difficulty getting my head around where Iam going wrong. In fact I have been stuck for two weeks now. All I am trying to do is post a comment back to database using the IRepository approach. I get the following error. I was hoping someone could enlighten me on where I might be going wrong here.

No parameterless constructor defined for this object

So here is my code...

Abstract Class

public interface IBlogRepository : IDisposable
    {
        IList<Entry> Posts();
        void InsertComment(Comment comment);
        void Save();

    }

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Inherited Class on the InsertComment method Comment being my database table. So I should be able to call in that and pass in my model to update table using this apporach with ease.

public class BlogRepository : IBlogRepository, IDisposable
    {
        private BlogDataDataContext _dataContext;
        public BlogRepository() { _dataContext = new BlogDataDataContext(); }

       // #region IBlogRepository Members

        public IList<Entry> Posts()
        {
            var entries = from m in _dataContext.Entries select m;
            return entries.ToList();
        }

        public void InsertComment(Comment comment)
        {
            _dataContext.Comments.InsertOnSubmit(comment);
        }

        public void Save()
        {
            _dataContext.SubmitChanges();
        }

        private bool disposed = false;

        protected virtual void Dispose(bool disposing)
        {
            if (!this.disposed)
            {
                if (disposing)
                {
                    _dataContext.Dispose();
                }
            }
            this.disposed = true;
        }

        public void Dispose()
        {
            Dispose(true);
            GC.SuppressFinalize(this);
        }

       // #endregion
    }

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Here is my ListView Model that validate comments and does some other stuff.

public class ListView
    {
        [Required(ErrorMessage = " A Name is required *")]
        [DisplayFormat(ConvertEmptyStringToNull = false)]
        [StringLength(160, MinimumLength = 2, ErrorMessage = "Must be between 2 & 160 characters in length.")]
        public string AuthorName { get; set; }

        [Required(ErrorMessage = "Email address required *")]
        [DisplayFormat(ConvertEmptyStringToNull = false)]
        [StringLength(160, MinimumLength = 2, ErrorMessage = "Must be between 2 & 160 characters in length *")]
        [EmailValidation(ErrorMessage = "Must be valid email *")]
        public string AuthorEmail { get; set; }

        [Required(ErrorMessage = " A Message is required *")]
        [DisplayFormat(ConvertEmptyStringToNull = false)]
        [StringLength(4000, MinimumLength = 2, ErrorMessage = "Must be between 2 & 4000 characters in length *")]
        public string Body { get; set; }
        
        public ListView(IBlogRepository blogRepository)
        {
            Posts = blogRepository.Posts();
        }

        public IList<Entry> Posts { get; private set; }
        public IList<Comment> Comment { get; private set; }
    }

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Here is my BlogController...

public class BlogController : Controller
    {
        
        private IBlogRepository _repository;
        public BlogController() : this(new BlogRepository()) { }
        public BlogController(IBlogRepository repository) {
 
            this._repository = repository;
        }

        public ActionResult BlogList(){
            var viewModel = new ListView(_repository);
            return View("BlogList", viewModel);            
        }     
        public ActionResult BlogPost(int id, string title){
            var viewModel = new ListView(_repository);            
            ViewData["id"] = id;
            return View("BlogPost", viewModel);
        }

        [HttpPost]
        public ActionResult BlogPost(ListView model)
        {
            // CANNOT GET TO HERE WITH ERROR.
            if (ModelState.IsValid) {
            
            
        
                return RedirectToAction("BlogPost");
            }
            return View();
        }
    }

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Here is my initial BlogList.cshtml file which displays each blog in a list. We then click and a get is sent to controller to fetch the right blog.

@model MyProgram.Models.ListView
@{
    Layout = "~/Views/Shared/_Layout.cshtml";
    Page.Title = "";
}

@section head{
 <meta name="description" content=""/>
}

<section>
    <div>
        <h1 class="customCol1">Blog List - Recent Posts</h1>
        @{
            foreach (var ch in Model.Posts)
            {
                <div class="blogDiv"> 
                    <div class="blogSummary" >                        
                            <ul><li class="lnkBlog">@Html.ActionLink(@ch.Title, "BlogPost", "Blog", new { id = @ch.EntryId, title = @ch.MetaTitle }, new { @class = "lnkBlogAct" })</li></ul>                        
                            <p class="blogListSummary">@ch.Summary.ToString()</p>
                            <span><strong>@ch.Published.ToString("dd/MM/yyyy HH:mm:ss")</strong></span>
                    </div>
                </div>
            }            
        }        
    </div>
</section>

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Here is my blogpost.cshtml which is where we display selected blog with comments section at the bottom. The problem is when I post the comments back to the server it should call the HTTPPOST method and then we can insertComment. I am having trouble passing the view back and cannot work out my glaring mistake.

@model MyProgram.Models.ListView
@{
    Layout = "~/Views/Shared/_Layout.cshtml";    
}
<script src="@Url.Content("~/Scripts/jquery.validate.min.js")"></script>
<script src="@Url.Content("~/Scripts/jquery.validate.unobtrusive.min.js")"></script>
@section head{
 <meta name="description" content="@ViewBag.Description" />
}

<article>
    <div>        
         @{            
            if (@ViewData["id"] != ""){
                int myVal = Convert.ToInt32(@ViewData["id"]);
                var myEntry = Model.Posts.Single(c => c.EntryId == myVal);
                
            <div class="blogContent" >
                <h1 class="blogH1">@myEntry.Title</h1>                
                <div class="blogEntry">@Html.Raw(myEntry.Body)</div>               
                <span class="blogPublished float-left">Posted by:&nbsp;&nbsp;@myEntry.Username</span>
                <span class="blogPublished float-right">Published Date & Time:&nbsp;&nbsp;@myEntry.Published.ToString("dd/MM/yyyy HH:mm:ss")</span>                
            </div>
                Page.Title = @myEntry.MetaTitle + " - Web Design Blog Post ";
                ViewBag.Description = @myEntry.MetaDescription;
            }
        } 
    </div>    
</article>
<div class="clear"></div>
<section>
    <div class="blogContent">
        <h1 class="blogH1">Leave a Comment</h1>
       @using (Html.BeginForm("BlogPost", "Blog"))
{
    <fieldset id="frmComments">
        <div class="frmBlogMessageContainer">
            <div class="frmBlogRwComments">
              <span class="lblBlogCntrls">@Html.LabelFor(model => model.AuthorName)*</span>
              <span>@Html.TextBoxFor(model => model.AuthorName, new { @class= "frmBlogCntrls", @maxlength = "100" })</span><br />
              <span class="lblBlogCntrls"></span>
              <span class="msgBlogComment">@Html.ValidationMessageFor(model => model.AuthorName)</span>
            </div>
            <div class="frmBlogRwComments">
              <span class="lblBlogCntrls">@Html.LabelFor(model => model.AuthorEmail)*</span>
              <span>@Html.TextBoxFor(model => model.AuthorEmail, new { @class= "frmBlogCntrls", @maxlength = "150" })</span><br />
              <span class="lblBlogCntrls"></span>
              <span class="msgBlogComment">@Html.ValidationMessageFor(model => model.AuthorEmail)</span>
            </div>
            <div class="frmBlogRwComments frmBlogCommentsMessage">
              <span class="lblBlogCntrls">@Html.LabelFor(model => model.Body)*</span>
              <span>@Html.TextAreaFor(model => model.Body, new { @class= "frmBlogCntrls", @cols = 40, @rows = 10  })</span><br />
              <span class="lblBlogCntrls">&nbsp;</span>
              <span class="msgBlogComment">@Html.ValidationMessageFor(model => model.Body)</span>
            </div>
            <br />
            <div class="frmBlogRwComments">
              <span class="lblBlogCntrls"></span>
              <span><input id="submit" name="submit" type="submit" value="Submit" /></span>
            </div>
        </div>
    </fieldset>
}
    </div>
</section>

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Any advice at all would really help. I wouldn't normally post so much code but I just cant fathom it at all and think I am completely missing the point somewhere.

In my ListView Model I have a constructor like this...

public ListView(IBlogRepository blogRepository)
{
Posts = blogRepository.Posts();
}

Now I believe this is causing an issue. I dont know MVC very well and wonder what I can do with this. Maybe moving it out into the controller. Or creating another contructor for overloading with different parameters. Please help.