This example is a simple CRUD application which allows the user to edit items in the Customers table of the Northwind database. Because we are only performing CRUD functions, I have not added a Business Logic Layer (BLL); if you are a purist, you could add a pass-through https://traderoom.info/ BLL; however, I feel it would add little to this example. The columns that are displayed in a grid can be chosen by the user through the column-chooser context menu, which can be enabled by setting the AllowColumnChooser defined on the view to true.

More details

Because MVVM allows us to separate the code that prepares the data for display and is responsible for handling user input from the code that manages the view. One of the benefits of using the Telerik UI for WPF toolkit is that you are stepping on the shoulders of giants. There is already an excellent document processing library that has been developed for Telerik tools, and of course it is well integrated into the Telerik WPF DataGrid. Controlling the appearance and paging options starts with the DisplayMode property. It is of type PagerDisplayModes flag enumeration, and its members control what is displayed by the pager. You can also control the size of the page, which is the number of items displayed at once on the screen.

Common interface controls

A Stats Editor Control which gives the user the ability to view, add, edit and remove the statistics displayed in StatRows. DataGridCollectionView class is essentially a collection, with some useful functionality built into it allowing Filtering, Grouping and Sorting. This article presents a sample demonstrating how to use those advanced features. Avalonia has only recently become production ready and because of that, the major 3rd party component providers like Telerik, DevExpress or Infragistics still have not released the components for Avalonia.

Additional controls and features in the Plus Edition

If we copy our customer data into an ObservableCollection and bind this to the DataGrid, we can handle the CollectionChanged event and perform the required operation on the DAL. The following code snippet shows how the CustomerObjectDataProvider (which is defined as an ObjectDataProvider in the XAML) constructs an ObservableCollection of CustomerUIObjects. These UI objects simply wrap their data object counterparts in order to expose the same properties. When a grid is in a table-view layout, the first n columns can be fixed so that they do not scroll with the grid content.

  1. If you are new to MVVM or need a refresher, take a moment to read an introduction to the MVVM pattern.
  2. Both of those approaches will work and can be shared among all your data grid instances, so choose the one that suits you.
  3. The CardView and CompactCardView classes provide card-view layouts for the data items in a grid.
  4. This article presents a sample demonstrating how to use those advanced features.

There are dark and light themes, a Material and touch-friendly theme. One of the coolest WPF features is the styling and template mechanism. Styles allow you to set the properties of a component in a tidy way and create a configuration that can be shared among many instances. Templates allow you to take control over the appearance of a component using ControlTemplate or the appearance of data using DataTemplate. What the creators of the DataGrid have done is take advantage of this mechanism and allowed you, the developer, to modify the appearance of the GridView (and any component for that matter) very granularly. Just this simple code change is all that is required to start using the power of IQueryable in your code.

The style of the column header can easily be modified via the ColumnHeaderStyle of the DataGrid. However, if you modify the background colour of the column header, you will find that the sort arrows disappear! This is because the arrows are not part of the ColumnHeader template; instead, they are added programmatically. However, it should be noted that the validation support for the WPF DataGrid is currently a bit patchy. The row level validation which was advertised as part of the first DataGrid CTP didn’t quite make the release, and the recently released DataGrid v1 still has a number of validation related issues.

Binding property simply allows the DataGrid to bind the column value to a property of the row — this is how the basic DataGrid (without any improvements from NP.Ava.Visuals) works. When declaring the DataGrid in code behind, a default view must be set. As cool as the DataTable API is, you should restrain yourself from using it except for cases of dynamic data as described above or when you are migrating an existing code base to WPF. Querying databases and displaying their data can be done using other, more modern techniques. If you are new to MVVM or need a refresher, take a moment to read an introduction to the MVVM pattern. In this post, I will assume you have a basic understanding of how MVVM works.

They are configured by the SelectionMode and SelectionUnit property. This project has adopted the code of conduct defined by the Contributor Covenant to clarify expected behavior in our community.For more information see the .NET Foundation Code of Conduct. This article will present a few common validation scenarios, demonstrating how the DataGrid can be configured to perform these tasks.

All database synchronisation logic is performed by handling event from this bound collection; therefore, there is no WPF DataGrid specific code. Handling delete operations is relatively straightforward, but how about updates or insertions? Furthermore, when a user adds a new item to the DataGrid, the object is initially added to the bound collection in a non-initialized state, so we would only ever see the object with its default property values.

The InsertionRow class represents a row in which values can be entered to insert a new item to the grid. Then, I use AddClassesToDataGridColumnHeaderBehavior attached behavior to inject the WithFilter DataGridColumnHeader class for every column within the DataGrid. CallAction is a very important and useful behavior defined within NP.Ava.Visuals package that will be explained in detail elsewhere. I have added all the above capabilities to the built-in Avalonia DataGrid aside from Grouping (which is on my list and should be added soon).

Cell level validation makes use of the standard Binding validation mechanisms which are described in great detail in this excellent CodeProject article. Row level validation makes use of the new .NET SP1 feature, BindingGroups. A binding group does pretty much what you would expect, it groups together a number of bindings, allowing them to be validated as a single entity.

In the event handler, we invoke the DAL DeleteCustomer method with the wrapped data object passed as the parameter. This works well enough; however, one of the advertised features of the WPF DataGrid is design-time support. If you right-click on the DataGrid in the Visual Studio designer, you will see a DataGrid entry wpf advanced datagrid in the context menu. However, the sub-menu is a little sparse, and displays the message «You need to set ItemsSource to enable some column operations». The problem is that the DataGrid designer is unable to inspect the contents of the ItemsSource property of the DataGrid if it has been constructed in the code-behind.

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