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Passing Parameters to Shell Viewmodel Using Unity BootStrapper With Prsim

I've created a dialog service using interfaces to show custom dialog/confirmation boxes (I know that Prism comes with this ability but the dialog boxes don't appear to be customizable and don't match my layout/color scheme). The dialog service has a register function that registers the dialog view type with dialog viewmodel type in a dictionary. This is done so that a viewmodel can be passed in and in a loosely coupled fashion, an instance of the needed view can be created. The code looks like this:
private readonly IDialogService dialogService = new DialogService(Application.Current.MainWindow);
// Registers the confirmation window viewmodel with the confirmation window view
dialogService.Register<ConfirmationWindowViewModel, ConfirmationWindow>();
so my initial thought was to try to create this in the unity bootstrapper (because of the registration passing in views and viewmodels) but I can't seem to find a way to do that and pass in the dialog service.
I must note that the constructor for the main window viewmodel also injects the region manager and the event aggregator for Prism; I had tried creating an instance in the bootstrapper and registering the instance but the creation of the region manager vs the injection causes errors. If I declare and initialize the dialog service in the main window viewmodel it of course works but from my understanding of MVVM we don't want the viewmodels to have any knowledge of the views so I'm trying to find another way to do it, without breaking IoC for region manager and event aggregator.
I am new to MVVM and Prism/Unity so my grasp of these concepts isn't fully solidified yet.

I know that Prism comes with this ability but the dialog boxes don't appear to be customizable and don't match my layout/color scheme
You can create whatever you like as dialog, just derive from PopupWindowAction and override CreateWindow (and other methods as needed) to create the dialog you always wanted.

In case anyone sees this later and is curious, my end decision was to get rid of the 'Register' function altogether in favor of a solid convention instead.
Previously, I would use this function and kept a dictionary of all the registered views/viewmodels:
dialogService.Register<ConfirmationWindowViewModel, ConfirmationWindow>();
this would register take the and store them in the dictionary so I could later pass in a viewmodel and create an instance of the appropriate confirmation message view. Instead I removed all code regarding this part of the solution and replaced it with some reflection mixed in with naming conventions.
Step 1: Ensure all views are named with the suffix View at the end.
Step 2: Ensure all viewmodels are named with the suffix ViewModel at the end.
Step 3: Ensure these are all in appropriately named namespaces (views in views namespace and viewmodels in viewmodels namespace).
(most of this ^^ is done anyway)
Final Step: Replaced dictionary with this code:
var viewTypeName = viewModel.GetType().AssemblyQualifiedName.Replace("Model", "");
var viewType = Type.GetType(viewTypeName);
in the dialog interface. Now, no matter what viewmodel is passed in, it will pull the appropriate view with less code and no necessary linking as was done before.

Passing Details From One Window to Another Window

I have a selection of TextBoxes that a user fills in when they wish to note that they have had contact with another person. Most of the TextBoxes are imply filled in by typing into them. However, for one of them I would like the user to be able to select from a list of People that appears when they click on a button.
This is where I am having problems. So far I have just made a DataGrid appear and handled it's SelectionChanged method to fill in the TextBoxes text property. This has worked fine, however now there is not enough space on the current page to show an entire DataGrid with all the people they can select from.
I've decided to show the People in a separate, smaller Window that appears when the user clicks a Button. The issue I have is that when the user selects the Person they wish to mark the contact for in the new Window, I have no idea how I can notify the original Window that a Person has been selected, close the new smaller Window and fill in the appropriate TextBox on the original Window.
What would be the most intuitive way to fill in the TextBox on the original Window, based on the selection on the Window that opens?

I would use delegates,which call a function of the original window and parse the changed variable with it. So you know when the user clicked something and you can directly react to this "event".
Link:
https://msdn.microsoft.com/en-us/library/ms173171.aspx

If you use a framework like Galasoft's MVVM Light (http://www.galasoft.ch/), they have a messenger system just for this purpose. It allows you to "broadcast" messages that can be "received" by any other part of the application

This is when considering using Domain, Model, Presentation (Winforms/WPF version of MVC formatting) to do your app.
You can have each form as its own class, well they are their own class. Create each form class but add some public members to it if the controls are private. Have them have "get" properties only and to return the values of whatever controls or variables are in that form. Your main form will be the controlling form. All forms will be handled by the main form so when you open it, it is a class the main form can access.
Now, if I remember (been doing more MVC and not any Winforms lately) I believe if you use the ShowDialog() method it will freeze the main thread so when you close out the main form you can continue and read in public members you have in your forms class you opened. Synchronous I believe it runs as. If you use just Show() the thread will keep on trucking, asynchronous. With asynchronous you may then have to use a main form in your startup code so there is always a window there but subscribe to the close event of your forms and have a method that can grab those public members out. Be sure to instantiate the extra forms at the root of the main class so it doesn't fall out of scope when it exists the method that calls it. You may even be able to make the method that calls is a async call and have an await before the command that runs the Show method on the form.
Summary, treat each form as its own class but add public members that can read the values from the controls and/or variables you want. Read that data from the class when it closes via an event or synchronously when the thread closes out from the form closing. The form closing doesn't discard the object, just the visualization of the form.
Oh, if you are passing info from the main form to a child for you are opening, either add a constructor for that form class that takes your input as a model or values to fill in the appropriate variables or forms before showing it or create a public property you can put your values you want to send in before showing the class.
Remember, everything is a class, once you look at it as such and treat it as such, the answer will come. :-)
I should warn, I am a long winded explainer.
At work putting all this down from memory so some errors may exist. Let me know if there are.

I think the problem is to access the controls of the main window, isn`t it?
You can define an event of changing user`s choise and access MainWindow control by using the following construction:
((MainWindow)Application.Current.MainWindow).MyTextBox

C# WinForms ShowDialog() call arbitrary method

I'm working on a console application that creates a form to alert users of some given state - at a later stage, the code base will become a class library.
For now, however, I need to show the form (ShowDialog would be the best method here, I guess) THEN call an arbitrary method before the form closes.
As an example, I need to show the form, set the text value of a label control, wait for n number of seconds, then change the value of the label, then close the form. I know that this sounds a little trivial, but I'm trying to proof-of-concept the design.
I've taken a look around and it doesn't look like this is possible, as ShowDialog() requires me to close the form before I can continue through code listing in the calling method/class.
Here's what I have so far:
PopUpForm myForm = new PopUpForm(string messageToDisplay);
myForm.ShowDialog();
//call myForm.someMethod() here, before the form closes
//dispose of the form, now that we've no use for it
myform.Dispose();
//target method in PopUpform class
public void someMethod()
{
lblText.Text = "Waiting for some reason";
//wait n number of seconds
lblText.Text = "Finished waiting. Form will now close";
//it doesn't matter if the form closes before the user can see this.
}
It looks like ShowDialog() doesn't support this sort of behaviour. I'm looking into BackgroundWorker threads, but was wondering if anyone has any advice on this, or have encountered this before.

If you want to show the form, then continue working, then close it - you can do so via Form.Show() instead of Form.ShowDialog():
using (var myForm = new PopUpForm(messageToDisplay))
{
myForm.Show(); // Show the form
DoWork(); // Do your work...
myForm.Close(); // Close it when you're done...
}
However, if this is purely a console application (and doesn't have a message pump), then this will likely not work properly.
Other options would be to provide a timer within your Form to have it close, or pass a delegate into the Form to run your method on Show, after which it could close itself.
at a later stage, the code base will become a class library.
When you do this, you'll likely want to come up with a different mechanism to provide notifications. Coupling your library to a specific UI technology is a bad idea. It would likely be better to have your library just provide events or other notification, and allow the user to provide the UI/notification to the user.

If this code ie destiend to end up in a code library, I recommend against having it display any forms, ever, of its own volition. The library should generate events, or in some cases exceptions, that can be caught by the invoking application to allow it to display the form. If certain details requiring presentation to the user are internal to the library, expose a DisplayEventData() method from the library.

The ShowDialog-method creates a "modal" window, and usually blocks the UI until you close it (either by clicking OK or Cancel). You would need to create a WinForm yourself, can be a simple one though and create a message-pump for it. You can run your own form by calling
Application.Run(YourForm);
You would need to hold your console-thread with a mutex for example, to keep it from continuing, while the form is open.
The form offers all the methods you know from WinForms like Close, where you could tell your console-thread to continue.
See this on MSDN.

MVVM Light - Child Views and Dialogs

I'm experimenting with MVVMLight and Windows Phone 7, and so far find it relatively easy. The one thing I can't get my head around is spawning new child windows/views. For example: if I want to create/navigate to a new view to allow a user to edit an item, then refresh the list of items from the database when they return, should I add some sort of handler for every activation of the view, or can I navigate to the edit view, then trigger a callback when the view is closed (NavigationService.GoBack is called).

What I use for this is the Messaging framework. Have the MainViewModel subscribe to a message that should cause it to refresh, then issue that message from the child page. The MainViewModel, still in memory, will hear that message and be able to respond. I have a sample of this on my blog at http://chriskoenig.net/2010/07/05/mvvm-light-messaging/, but note that you can also create your own custom messages (I personally do this all the time) and then just raise them manually:
// In MainViewModel
Messenger.Default.Register<ChildProcessCompleteMessage>(this, () => RefreshData());
// In ChildViewModel
Messenger.Default.Send<ChildProcessCompleteMessage>(new ChildProcessCompleteMessage());
This is a pattern I use quite a bit in my apps to allow communication between the view models. I'm not sure if this fully answers your question, so let me know if you need more info.

Error Creating Control - Custom Control

I have a custom control and it works fine...except that the control cannot be rendered on Design Time. ( I am using VS 2008)
I am thinking many people who develop custom controls encounter this problem...The error I get is "Error Creating Control - CustomControlName" Object reference not set to an instance of an object.
I want a work around. or at least debug this...(Since this is a design time issue how to debug?)
I have tried if( !DesignMode) code on OnInit, OnPreRender, RenderContents, CreateChildControls Methods ( I am just shooting in the dark)...
Help pls. I really hope this is not a VS bug!

BFree's comment is the most likely issue, for a control to display in the design view it needs a parameterless constructor as the design viewer doesn't know how you would normally instantiate the control.
If you do have a parameterless constructor, can you paste some code in to show what's happening?

As Glenn mentioned the first issue could be no parameterless constructor.
The second could be you are calling methods during the OnLoad or other methods you mentioned that have parameters that are not initialized or some sort of attempt at database calls etc that is normally done at run-time.
Unless they fixed this bug recently* and I'm not aware, something to keep in mind is the DesignMode property works for the first and second level of nested controls but beyond that it normally doesn't work right. (Such as form containing a UserControl[1] that holds another UserControl[2], the DesignMode works on the form and [1] but not [2]).
Also to agree with Glenn, seeing some of the code will help.
*From my very recent experience working with nested usercontrols it hasn't been fixed.

In your OnPreRender & CreateChildControls methods it's making a call to this.Page. You might want to try wrapping them in a
if (this.Page != null)
{
.....
}
Because I don't think you'll have a Page object at that point & I'm pretty sure PreRender & CreateChildControls will be called in design view. I haven't written custom server controls for a while though, so I could be wrong (been working in MVC lately).

Glenn, the error ur getting a VS bug and no fix has been released yet.