How do I add data to the WPF ListView items like Windows Forms?
Using databinding you can bind the itemssource to something like an observable collection then have your items added to that.
This approach makes it fairly easy to manipulate the data once you get used to databinding as long as you have INotifyPropertyChanged implemented your listview will update when you call OnPropertyChanged().
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I am pretty new to WPF MVVM, so pardon me if I understood MVVM concepts wrongly.
I have a DataGrid in my View, which I have bound the ItemsSource to an ObservableCollection<M> in the ViewModel. The M class is a Model class. However, the M class has bool properties, which are to be displayed in the DataGrid as "Yes/No" strings.
Currently, I am using a Converter to convert the bool value to string. But, it just feels wrong for the ViewModel to expose a list (ObservableCollection) of a Model to the View. I have also read that in MVVM, conversions should be done at ViewModel. So, what is the right way to implement this the MVVM way for a DataGrid?
In an ideal world, you would wrap your Model objects in their own ViewModel so that your ObservableCollection contains a ViewModel type with those bool Model properties converted to Yes/No string properties.
However, in a pragmatic world, if you are not editing those values, I wouldn't bother except to note that if you are exposing many of those bool properties and have many thousands of rows, you will take a performance hit on rendering the grid while the DataGrid instantiates a Converter per property and row.
Using converters is not a wrong way. As per my suggestion, you should bind the data as you're doing now and in the view you can create and use a BoolToStringConverter for converting the boolean value to yes or no.
I am fairly new to WPF and MVVM.
I see that a DataGrid can be bound to a CollectionViewSource or an ObservableCollection or a DataSet.
What is the significance of using one over the other?
CollectionViewSource is the XAML equivalent (can be instanciated in XAML) for CollectionView, which provides functionality for grouping, sorting, filtering, and navigating in any data collection. If you want to provide any of these features in the view (XAML) only and do not want to do this in the viewmodel, use a CollectionViewSource else use the ObservableCollection or CollectionView in your viewmodel. Use a DataSetwhen you have your data already in that form and do not want to go through the hassle of creating a viewmodel.
I mostly use the ObservableCollection in the viewmodel.
I would not recommend you using DataSet. You could sort, group and filter data using CollectionViewSource.
I have a WPF user control ...which is in MVVM. The user control(which contains a listview) need data from the page (where it is included). I have to set a property to get this data input. Will this comply with MVVM...if not, what is the way for the same?
I'm afraid this won't be correct in MVVM design pattern. try to stick to your view model to define properties. Why don't you consider moving that property to control's vm?
Use an ObservableCollection rather.
ObservableCollection<myModel> myOC = new ObservableCollection<myModel>();
where myModel is a class that has to be constructed transforming your columns in the DataTable to Properties.
In your MainViewModel, loop through the DataReader and create myOC out of it.
Now bind myOC to a ListView in your page.
The DataTemplate of ListView should be a view(UserControl) drawing data from a ViewModel constructed out of myModel
But your UserControl has the entire ListView inside. If that is on purpose, then let me know the entire design to give a better idea.
I'm having difficulty correctly Data Binding my models in the view. I have a MainWindowViewModel which contains a list of AlbumViewModels. Each AlbumViewModel holds an AlbumModel. So I have multiple albums and I need to display information in an ObservableCollection in the AlbumModel. I have two ListBoxes. ListBox1 holds the list of AlbumViewModels that are in my MainWindowViewModel. My second ListBox I want to display the ObservableCollection from the current selected item from the AlbumViewModel.AlbumModel. How can I do this? I've tried binding the DataContext of ListBox2 to the ListBox1 element, along with SelectedItem as the path but that returns 'AlbumViewModel'. Is there anyway to bind ItemsSource of a ListBox to the binding of the DataContext, but in this case binding it to [DataContext].AlbumModel.ObservableCollection or something?
I apologise if it sounds rather complicated!
You can use the fact, that when you bind to a collection, WPF wraps collection to CollectionView. And this guy has CurrentItem.. Bea had good article: How can I sync selection of two data bound ListBoxes? and Dr.WPF is amazing (as usual): ItemsControl: 'C' is for Collection.
I want to display a bunch of Objects i have created in a ListBox. My objects implement the INotifyPropertyChanged Interface.
I tried to use an ObservableCollection, which i have bound to a listbox Control (listbox1.DataContext = MyCollection)
But this does not exactly what i want to do, because the Listbox is not refreshed when one of the properties of one of my objects in MyCollection changes.
I have found this blogposting: http://sweux.com/blogs/psampaio/index.php/2009/04/13/creating-a-custom-observable-collection-in-wpf
is this realy the easyiest/only way to keep track of several objects?
I'm not sure, but have you tried using a datatemplate for your listbox items? like, a textbox that explicitly sets it's text to the appropriate binding.