Mapping multiple instances of a view/viewmodel pair to different regions

Question

Hi,

I'm using prism/silverlight. I've created a view that has several components like datagrids,textboxes and buttons and it has a corresponding viewmodel. I need to map multiple instances of this view to different regions in my shell. For e.g., I want one instance of the view in one tab item, another instance in another tab item both of which independently map to independent view models instances. This is because the functionality is the same but they are different entities. How do i implement this?  

Answer 1

Hi,

You can create that ViewModel with property with any entyties you would and then override DataContext match you control

Regards

Answer 2

I dont understand. could you elaborate?

Answer 3

Do you have two tab items and two ViewModel use the same Function,your can do that just override DataContext

DataContext="{Binding Current.Reference}" or you can create one ViewModel that feed the whole Views

one ViewModel can contain multiple Entyties

Command="{Binding StaticResources Key}"

Answer 4

I need 2 instances of the same viewmodel to map to 2 identical views in separate tab items

Answer 5

Hello,

Look at http://msdn.microsoft.com/en-us/library/gg405494%28PandP.40%29.aspx

Else you can use LifetimeManager if using unity else NonShared if using MEF for create on new instance each invoke

Answer 6

what am i looking for in the link? lifetimemanager looks promising.will check that out

Answer 7

Hi,

Are You ViewModel just present Data Model or command too?

 

Answer 8

My viewmodel has an observablecollection that binds to a datagrid in my view

Answer 9

<usercontrol.DataContext>

<you viewmodel/>

</usercontrol.DataContext>

<sdk:tab   DataContext="{Binding Customers}"    

<sdk:tab   DataContext="{Binding CustSex}"    

 

CSDomainContext Context = new CSDomainContext();

        private PagedCollectionView _customers;
        public PagedCollectionView Customers
        {
            get
            {
                if (_customers == null)
                {
                    _customers = new PagedCollectionView(Context.Customers);
                }
                return _customers;
            }
            set
            {
                if (_customers != value)
                {
                    _customers = value;
                }
            }
        }

        private PagedCollectionView _custSex;
        public PagedCollectionView CustSex
        {
            get
            {
                if (_custSex == null)
                {
                    _custSex = new PagedCollectionView(Context.Customers);

                }
                return _custSex;
            }
            set
            {
                if (_custSex != value)
                {
                    _custSex = value;
                }
            }
        }

Thanks and Regards

Answer 10

A button in the view uses eventaggregator to add data to the datagrid. On click, it calls a function using 'subscribe'. But this function is set to add data to the first pagedcollection. How can i customize it to send the data to the corresponding datagrid?

Also, isnt there a way I can just declare multiple instances and map them to their regions? This doesnt seem very scalable

Answer 11

Hi,

You class have to impletement INotifyPropertyChaned interface

Check this link http://forums.silverlight.net/forums/t/211765.aspx

public abstract class ViewModelBase : INotifyPropertyChanged, IDisposable

Regards

Answer 12

Isnt there someway I can directly declare multiple instances of the viewmodel? This doesnt seem very scalable

Answer 13

The above is Synchronized you have to create that with Asynchronized

Class ViewModel : INotifyPropertyChanged

private ListCollectionView _ArGroupCodes;
        public ListCollectionView ArGroupCodes
        {
            get
            {
                if (_ArGroupCodes == null)
                {
                    _ArGroupCodes = new ListCollectionView((new MozillaFXEntities()).ArGroupCode.ToList<ArGroupCode>());
                    //_ArGroupCodes = new ListCollectionView(new ObservableCollection<ArGroupCode>(dc.ArGroupCode));
                }
                return _ArGroupCodes;
            }
            set
            {
                if (_ArGroupCodes != value)
                {
                    _ArGroupCodes = value;
                    OnPropertyChanged("ArGroupCodes");
                }
            }
        }

http://forums.silverlight.net/forums/p/212764/502436.aspx#502436

what is the problem now?