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ImageColumn Class

A column type that allows you to display images.

Namespace: DevExpress.Mobile.DataGrid

Assembly: DevExpress.Mobile.Grid.v18.2.dll

Declaration

public class ImageColumn :
    GridColumn

Remarks

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.

Example

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.

GridColumns_All_iOS

GridColumns_All

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.

Inheritance

Object
GridColumn
ImageColumn
See Also