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QuestionHas any one seen a good video series on the complete proess of going from SketchFlow ProtoType -> Application? Pin
ProtoBytes22-Oct-10 11:02
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QuestionI should know the answer to this question, how do you create writeablebitmap images in WPF / Silverlight 4 Pin
ProtoBytes22-Oct-10 10:57
ProtoBytes22-Oct-10 10:57 
QuestionI am using Blend Studio 4 - Designer, where is the GPU acceleration? Pin
ProtoBytes22-Oct-10 10:45
ProtoBytes22-Oct-10 10:45 
QuestionSilver Light / WPF .NET 4.0 Pin
ProtoBytes22-Oct-10 10:38
ProtoBytes22-Oct-10 10:38 
QuestionHow using dataform and WCF Pin
Coban_22-Oct-10 2:56
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AnswerRe: How using dataform and WCF Pin
Abhinav S23-Oct-10 17:57
Abhinav S23-Oct-10 17:57 
QuestionProblem consuming a WCF service + Silverlight 4 Pin
CrafterIt22-Oct-10 2:01
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AnswerRe: Problem consuming a WCF service + Silverlight 4 Pin
SledgeHammer0122-Oct-10 6:41
SledgeHammer0122-Oct-10 6:41 
GeneralRe: Problem consuming a WCF service + Silverlight 4 Pin
CrafterIt26-Oct-10 3:17
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QuestionAssign Datagrid Value From Child Web Page To A Textbox In Parent Webform by silverlight Pin
ya_yayeeh21-Oct-10 22:44
ya_yayeeh21-Oct-10 22:44 
QuestionRowDetailsTemplate - Can't Edit Data [modified] Pin
eddieangel21-Oct-10 14:27
eddieangel21-Oct-10 14:27 
QuestionGridView displaying 2 columns with custom controls Pin
Gareth H20-Oct-10 3:03
Gareth H20-Oct-10 3:03 
AnswerRe: GridView displaying 2 columns with custom controls Pin
Gareth H20-Oct-10 23:08
Gareth H20-Oct-10 23:08 
AnswerRe: GridView displaying 2 columns with custom controls Pin
Gareth H21-Oct-10 6:12
Gareth H21-Oct-10 6:12 
QuestionHow to check if i'm in run-time or design time ? Pin
Yanshof20-Oct-10 3:03
Yanshof20-Oct-10 3:03 
AnswerRe: How to check if i'm in run-time or design time ? Pin
Gareth H20-Oct-10 3:53
Gareth H20-Oct-10 3:53 
QuestionHow to create a listview with multiple datatemplates Pin
Member 324168819-Oct-10 10:30
Member 324168819-Oct-10 10:30 
QuestionHow to change image\parameters on style definition ? Pin
Yanshof18-Oct-10 21:52
Yanshof18-Oct-10 21:52 
AnswerRe: How to change image\parameters on style definition ? Pin
Abhinav S19-Oct-10 3:55
Abhinav S19-Oct-10 3:55 
Questioncombo box items are not going up/down from keyboard arrow keys. Pin
SRKSHOME17-Oct-10 23:13
SRKSHOME17-Oct-10 23:13 
QuestionWPF MVVM design time data? Pin
SledgeHammer0117-Oct-10 19:42
SledgeHammer0117-Oct-10 19:42 
AnswerRe: WPF MVVM design time data? Pin
SledgeHammer0117-Oct-10 20:03
SledgeHammer0117-Oct-10 20:03 
QuestionA few newb MVVM (WPF) questions... Pin
SledgeHammer0117-Oct-10 16:53
SledgeHammer0117-Oct-10 16:53 
Say I have a dialog with a list box and 3 buttons: Add, Edit and Delete. The listbox displays a list of Widget objects.

I'm assuming the "proper MVVM way" is to do something like:

class ViewModel
{
public ObservableCollection<widget> Widgets { ... };
public Command AddCommand { ... };
public Command EditCommand { ... };
public Command DeleteCommand { ... };
}

Add then the ListBox.ItemsSource binds to Widgets, the Add button to AddCommand, Edit to EditCommand and so on...

Now is where I get confused on MVVM...

1) Typical Add button behavior is to auto select the new item. How would that happen? It was suggested to me that ViewModel expose a "CurrentItem" property for **2-way** data binding with the listbox. The AddCommand handler would update the CurrentItem after it creates it. Is this a good idea? To me, that seems hokey as it would force that behavior on everybody using the view model. Also, it would set that property in situations where it may not want to be set. Any ideas?

2) Obviously, Edit and Delete need to be disabled if no item is selected. I know how to do that the "non MVVM" way, but what is the MVVM way? I know the command has a CanExecute handler. Should all that logic happen in there? It would seem I would either need the list box or the selected item and the collection.

I guess I'm just trying to figure out where the line should be drawn at which code goes in the code behind and which goes in the view model.

I understand MVVM "purists" say ZERO code in the code behind, but it seems to me like you'll be creating a lot of properties, commands, etc and jumping through a lot of hoops to have all the bindable properties in the view model.
AnswerRe: A few newb MVVM (WPF) questions... Pin
Abhinav S17-Oct-10 18:17
Abhinav S17-Oct-10 18:17 
AnswerRe: A few newb MVVM (WPF) questions... Pin
Mycroft Holmes17-Oct-10 23:40
professionalMycroft Holmes17-Oct-10 23:40 

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