I have a silverlight ListBox that has it's ItemsSource set. From the C# code behind I want to loop through each ListBox item and change the value of the text and access controls that are in the ListBox ItemTemplate. How would I do that?
ListBox controls in silverlight are bound to an ienumerable type, so that if any value in the ListBox changes, the underlying data is changed and vice versa depending on what type of binding you require. To effectively iterate the items you'll want to iterate through the enumerable object you've bound to.
You can get to the collection by accessing the ListBox.ItemsSource property and change the text of appropriate items, perform LINQqueries etc. If you have bound the controls correctly, saving the collection should update the list.
Hope this helps!
Related
i have a datagrid bound to a property. In this grid i have columns which consists of cells which are like hyperlink i mean when user clicks on the cell value based on these values another gird will get populated. i want to know how to get the cell value and pass it to some method so that other grid will get populated.
The best way to do this is in your viewmodel.
You should bind the SelectedItem of your datagrid to a new property in your ViewModel. In the set method of this new Property, call a new method to populate a new ObservableCollection/List/whatever...
Finally, bind your "other grid" ItemsSource to this new observable collection from your ViewModel.
Edit:
If you need to load one thing or another depending on the column you are going to use the code behind, take a look at this:
Silverlight DataGrid how to get cell value from a selected item?
I have WPF window containing a listview that has it's itemsource set to a collection of objects. When I access SelectedItem or SelectedItems[] or Items[], I get the my object back that's bound to that item, not the ListViewItem item itself. I have no idea how to select a row and change it's color since I can't access the item itself, like a winform listviewitem.
ListView derives from ItemsControl which exposes the ItemContainerGenerator property. This object allows you to map a bound entity to its ItemContainer (the item your are looking for) and back.
I have a view where I've got an object bound to a treeview. The object has a number of collections (of different types) so I'm using hiearchical templates with a CompositeCollection to display them in the treeview.
I've then got a textbox that is bound to the treeview's selectedItem. Here I'm serialising the selectedItem to XML and displaying it in the textbox for editing.
All good so far. However, the big problem I have is that I can't use 2-way databinding with the SelectedItem property of the treeview as it is read only.
How can I cleanly keep the textbox edits in sync with my object that is bound to the treeview?
I do not think you need to do two-way databinding on the SelectedItem itself, you should expose a property in the class of your bound object which returns the serialized string and upon set modifies the object appropriately. This should be easier than dealing with the object as a whole.
Your XML stream must be represented as a property on your SelectedItem node, and your TextBox must be bound to that, somehow. The SelectedItem is read-only, but the object it refers to is not. If you two-way bind on that property, you should be able to affect your edits correctly. This would be done in the DataTemplates and HiearchicalDataTemplates you are using, since they are bound to the underlying data representation of the nodes you are representing with the TreeView.
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.