Create Columns and Bind Them to Data Fields

• Apr 19, 2019
• 5 minutes to read

Important

This documentation topic describes legacy technology. We no longer develop new functionality for the GridControl and suggest that you use the new DataGridView control instead.

To work with a GridControl, bind it to a data source. To do this, you need to create columns and bind them to data fields. There are two ways to add columns to a grid and associate them with data fields of the underlying data source.

• Create columns for all fields of the bound data source automatically.

  By default, a GridControl instance automatically generates columns based on the bound data source - one column for one field of a data source object, except complex fields. In terms of objects, a complex field can be a field of the nested object. A complex field name is constructed in the “String1.String2” form. For example, in Lesson 1 of the Getting Started tutorial, a grid displays orders. Columns for the Date, Shipped and Quantity properties of an Order object are generated automatically, however columns for fields of a related Product are not created (you can create columns bound to these complex fields in the grid manually by using the “Product.Name” and “Product.UnitPrice” field names, as shown in Lesson 2).

  

  The order of columns generated automatically in the grid is the same as the order of fields in the data source. You can prevent columns from being automatically created or set another mode of auto generating columns, using the GridControl.AutoGenerateColumnsMode property.

• Create columns and bind them to fields manually.

  You can manually specify a collection of grid columns. To do this, create corresponding column objects, bind each column to the corresponding data field using the GridColumn.FieldName property and add columns to the GridControl.Columns collection in the order you want to show them in the grid. You can manage the grid’s collection of columns in XAML or C# code.

Create and Bind Columns in XAML

This example shows how to add columns to GridControl to display and edit data of different types. The grid is bound to a collection of Employee objects. Each Employee object contains an employee’s photo (image), name, position, phone, address (strings), hire and birth dates (DateTime values), a value that specifies an employee’s access level, and a Boolean value indicating whether an employee is on vacation.

Grid columns are stored in the GridControl.Columns collection. An individual column is specified by a GridColumn descendant, which is appropriate to the type of data contained in this column. In this example, to display information on employees and allow end-users to edit it, the following columns are created in the grid.

Grid Column	Description
Photo ImageColumn	This column displays employee photos which are images added to a project as embedded resources.
Employee TemplateColumn	A cell in this column displays three employee properties: Name, Position and HireDate. A cell appearance is defined via a template. Each cell contains three Xamarin.Forms.Label elements within a Xamarin.Forms.Grid. Each Label element is bound to a property of the Employee class. A cell template data context is specified by the CellData object. Its CellData.Value property provides access to a value of a data field assigned to the column’s GridColumn.FieldName property. In this example, a column cell displays not only this field value but also values of two more fields. So, it is required to specify the whole data row as a binding source for the template. To do this, set the BindingContext property of the Grid to CellData.Source. Note that BindingContext specified for the Grid is inherited by all its children. This means that all Label elements have the same BindingContext as the Grid, and you can specify their simple bindings to properties of that object (Employee). Use the GridColumn.AllowSort, GridColumn.AllowGroup and GridColumn.IsReadOnly properties to prevent end-users from sorting and grouping data in the grid by this column and disable data editing.
Phone NumberColumn	The employee’s Phone property is of the string type. The keyboard allowing text input is automatically displayed when an end-user activates this column cell to edit an employee’s phone.
Address TextColumn	This column is bound to the employee’s Address string property. The keyboard allowing text input is automatically displayed when an end-user activates this column cell to edit an employee’s address.
Birth Date DateColumn	This column displays and allows editing employee birth days. The GridColumn.DisplayFormat property specifies the format of displaying dates.
Access Level PickerColumn	The employee’s Access property is of the AccessLevel type which is an enumeration with values Admin and User. To allow editing an employee’s access level by selecting one of two enumeration values, this property is bound to the grid’s picker column.
On Vacation SwitchColumn	The employee’s OnVacation property is of the Boolean type, so it is bound to the grid’s switch column which allows editing a cell value by selecting between two states.

Create and Bind Columns in C#

The following example shows how to create columns and bind them to data fields using C# code.

C#

using DevExpress.Mobile.DataGrid;
// ... 

GridControl grid = new GridControl ();
grid.Columns.Add (new TextColumn (){FieldName = "Product.Name", Caption = "Product" });
grid.Columns.Add (new NumberColumn (){FieldName = "Product.UnitPrice", Caption = "Price", DisplayFormat="C0" });
grid.Columns.Add (new NumberColumn (){FieldName = "Quantity"});
grid.Columns.Add (new DateColumn (){FieldName = "Date", DisplayFormat="d" });
grid.Columns.Add (new SwitchColumn (){FieldName = "Shipped"});