ASPxCardView.CustomCallback Event

Fires when a round trip to the server has been initiated by a call to the client ASPxClientCardView.PerformCallback method.

Namespace: DevExpress.Web

Assembly: DevExpress.Web.v24.1.dll

NuGet Package: DevExpress.Web

Declaration

C#

public event ASPxCardViewCustomCallbackEventHandler CustomCallback

VB.NET

Public Event CustomCallback As ASPxCardViewCustomCallbackEventHandler

Event Data

The CustomCallback event's data class is ASPxCardViewCustomCallbackEventArgs. The following properties provide information specific to this event:

Property	Description
Parameters	Gets a string that contains specific information (if any) passed from the client side. Inherited from ASPxGridCustomCallbackEventArgs.

Remarks

The CustomCallback event allows any desired server-side processing to be performed in response to a call to the client ASPxClientCardView.PerformCallback method.

Use the ASPxGridCustomCallbackEventArgs.Parameters property to get the information passed from the client side.

Note

Don’t export the ASPxCardView’s content during callbacks, because ASP.NET does not support sending binary content during a callback.

Example

The example below uses two ASPxCardView controls to display master-detail data.

Default.aspx

<dx:ASPxCardView ID="ASPxCardView1" runat="server" AutoGenerateColumns="False" DataSourceID="dsCategories" KeyFieldName="CategoryID">
    <ClientSideEvents FocusedCardChanged="function(s, e) {
        cardView2.PerformCallback(s.GetFocusedCardIndex());    
    }" />
    <Settings ShowTitlePanel="True" />
    <SettingsBehavior AllowFocusedCard="True" />
    <SettingsText Title="Categories" />
    <SettingsPager>
        <SettingsTableLayout RowsPerPage="2" />
    </SettingsPager>
    <Columns>
        <dx:CardViewTextColumn FieldName="CategoryID" ReadOnly="True" VisibleIndex="0" Visible="false">
        </dx:CardViewTextColumn>
        <dx:CardViewTextColumn FieldName="CategoryName" VisibleIndex="1">
        </dx:CardViewTextColumn>
        <dx:CardViewTextColumn FieldName="Description" VisibleIndex="2">
        </dx:CardViewTextColumn>
    </Columns>
</dx:ASPxCardView>  
<br />
<dx:ASPxCardView ID="ASPxCardView2" KeyFieldName="ProductID" OnCustomCallback="ASPxCardView2_CustomCallback" ClientInstanceName="cardView2" runat="server" AutoGenerateColumns="False">
    <SettingsText Title="Products" />
    <SettingsPager>
        <SettingsTableLayout RowsPerPage="2" />
    </SettingsPager>
    <Settings ShowTitlePanel="True" />
    <Columns>
        <dx:CardViewTextColumn FieldName="ProductID" ReadOnly="True" Visible="False" VisibleIndex="0">
        </dx:CardViewTextColumn>
        <dx:CardViewTextColumn FieldName="ProductName" VisibleIndex="1">
        </dx:CardViewTextColumn>
        <dx:CardViewTextColumn FieldName="UnitPrice" VisibleIndex="2">
        </dx:CardViewTextColumn>
        <dx:CardViewTextColumn FieldName="UnitsInStock" VisibleIndex="3">
        </dx:CardViewTextColumn>
        <dx:CardViewTextColumn FieldName="QuantityPerUnit" VisibleIndex="4">
        </dx:CardViewTextColumn>
        <dx:CardViewTextColumn FieldName="CategoryID" Visible="False" VisibleIndex="5">
        </dx:CardViewTextColumn>
    </Columns>
</dx:ASPxCardView>  
<br />
<asp:AccessDataSource ID="dsCategories" runat="server" DataFile="~/App_Data/nwind.mdb"
    SelectCommand="SELECT [CategoryID], [CategoryName], [Description] FROM [Categories]">
</asp:AccessDataSource>
<asp:AccessDataSource ID="dsProducts" runat="server" DataFile="~/App_Data/nwind.mdb"
    SelectCommand="SELECT [ProductID], [ProductName], [CategoryID], [UnitPrice], [UnitsInStock], 
    [QuantityPerUnit] FROM [Products] WHERE ([CategoryID] = ?)">
    <SelectParameters>
        <asp:SessionParameter Name="CategoryID" SessionField="CategoryID" Type="Int32" />
    </SelectParameters>
</asp:AccessDataSource>

Default.aspx.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using DevExpress.Web;

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e) {
        if (Session["CategoryID"] != null)
        {
            ASPxCardView2.DataSource = dsProducts;
            ASPxCardView2.DataBind();
        }
    }
    protected void ASPxCardView2_CustomCallback(object sender, DevExpress.Web.ASPxCardViewCustomCallbackEventArgs e) {
        object masterKeyValue = ASPxCardView1.GetCardValues(Convert.ToInt32(e.Parameters), "CategoryID");
        Session["CategoryID"] = masterKeyValue;
        ASPxCardView2.DataSource = dsProducts;
        ASPxCardView2.PageIndex = 0;
        ASPxCardView2.DataBind();

    }
}

Default.aspx.vb

Imports System
Imports System.Collections.Generic
Imports System.Linq
Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports DevExpress.Web

Partial Public Class _Default
    Inherits System.Web.UI.Page

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
        If Session("CategoryID") IsNot Nothing Then
            ASPxCardView2.DataSource = dsProducts
            ASPxCardView2.DataBind()
        End If
    End Sub
    Protected Sub ASPxCardView2_CustomCallback(ByVal sender As Object, ByVal e As DevExpress.Web.ASPxCardViewCustomCallbackEventArgs)
        Dim masterKeyValue As Object = ASPxCardView1.GetCardValues(Convert.ToInt32(e.Parameters), "CategoryID")
        Session("CategoryID") = masterKeyValue
        ASPxCardView2.DataSource = dsProducts
        ASPxCardView2.PageIndex = 0
        ASPxCardView2.DataBind()

    End Sub
End Class