DashboardViewer.DataLoading Event

Allows you to provide data for the DashboardObjectDataSource.

Namespace: DevExpress.DashboardWin

Assembly: DevExpress.Dashboard.v19.1.Win.dll

Declaration

C#

public event DataLoadingEventHandler DataLoading

VB.NET

Public Event DataLoading As DataLoadingEventHandler

Event Data

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

Property	Description
Data	Gets or sets data for the current data source.
DataSourceComponentName	Get the component name of the data source for which the event has been raised.
DataSourceName	Gets the name of the data source for which the event has been raised.
Parameters	Provides access to parameter values passed to the object data source.

Remarks

The DataLoading event is raised when the dashboard needs to load data from a data source assigned using the DashboardObjectDataSource. Use the event parameter’s DataLoadingEventArgs.Data property to provide data for this data source. This object should implement the IEnumerable or IListSource interface.

For other data source types (for instance, DashboardSqlDataSource or DashboardOlapDataSource), you can handle the DashboardViewer.ConfigureDataConnection event to customize connection parameters.

Example

The following example demonstrates how to bind a dashboard to a List object.

In this example, information about the sold units quantity is provided at runtime. The dashboard data source is added to the Dashboard.DataSources collection on the first load.

To update the displayed data, the DashboardViewer.ReloadData method is called. This raises the DashboardViewer.DataLoading event and allows supplying the dashboard with updated data.

Note

A complete sample project is available at https://github.com/DevExpress-Examples/how-to-bind-a-dashboard-to-a-list-object-e5171.

Data.cs

using System;
using System.Collections.Generic;
using System.Threading;

namespace Dashboard_BindingToList {
    public class Data {
        public string SalesPerson { get; set; }
        public int Quantity { get; set; }

        public static List<Data> CreateData() {
            List<Data> data = new List<Data>();
            string[] salesPersons = { "Andrew Fuller", "Michael Suyama", "Robert King", "Nancy Davolio",
                "Margaret Peacock", "Laura Callahan", "Steven Buchanan", "Janet Leverling" };

            for (int i = 0; i < 100; i++) {
                Data record = new Data();
                int seed = (int)DateTime.Now.Ticks & 0x0000FFFF;
                record.SalesPerson = salesPersons[new Random(seed).Next(0, salesPersons.Length)];
                record.Quantity = new Random(seed).Next(0, 100);
                data.Add(record);
                Thread.Sleep(3);
            }
            return data;
        }
    }
}

Form1.cs

using DevExpress.DashboardCommon;
using DevExpress.DataAccess;
using DevExpress.XtraEditors;

namespace Dashboard_BindingToList {
    public partial class Form1 : XtraForm {
        public Form1() {
            InitializeComponent();
            dashboardViewer1.DataSourceOptions.ObjectDataSourceLoadingBehavior = DocumentLoadingBehavior.LoadAsIs;
        }

        private void Form1_Load(object sender, System.EventArgs e) {
            Dashboard dashboard = new Dashboard();
            DashboardObjectDataSource objectDataSource = new DashboardObjectDataSource("Data Source 1");
            objectDataSource.DataSource = typeof(Data);
            objectDataSource.DataMember = "CreateData";
            dashboard.DataSources.Add(objectDataSource);

            // Creates a Pie dashboard item that displays share of sold units quantity per sales person.
            PieDashboardItem pies = new PieDashboardItem();
            pies.DataSource = dashboard.DataSources[0];
            Dimension salesPersonArgument = new Dimension("SalesPerson");
            Measure quantity = new Measure("Quantity");
            pies.Arguments.Add(salesPersonArgument);
            salesPersonArgument.TopNOptions.Enabled = true; salesPersonArgument.TopNOptions.Count = 3;
            salesPersonArgument.TopNOptions.Measure = quantity;
            pies.Values.Add(quantity);

            // Creates a Grid dashboard item that displays sales persons and corresponding quantities.
            GridDashboardItem grid = new GridDashboardItem();
            grid.DataSource = dashboard.DataSources[0];
            grid.Columns.Add(new GridDimensionColumn(new Dimension("SalesPerson")));
            grid.Columns.Add(new GridMeasureColumn(new Measure("Quantity")));

            dashboard.Items.AddRange(pies, grid);
            dashboardViewer1.Dashboard = dashboard;
        }

        // Handles the DashboardViewer.DataLoading event to provide the dashboard with new data.
        private void dashboardViewer1_DataLoading(object sender, DataLoadingEventArgs e) {
            if (e.DataSourceName == "Data Source 1")
                e.Data = Data.CreateData();
        }

        private void button1_Click(object sender, System.EventArgs e) {
            // Reloads data in data sources.
            dashboardViewer1.ReloadData();
        }
    }
}

Form1.vb

Imports DevExpress.DashboardCommon
Imports DevExpress.DataAccess
Imports DevExpress.XtraEditors

Namespace Dashboard_BindingToList
    Partial Public Class Form1
        Inherits XtraForm

        Public Sub New()
            InitializeComponent()
            dashboardViewer1.DataSourceOptions.ObjectDataSourceLoadingBehavior = DocumentLoadingBehavior.LoadAsIs
        End Sub

        Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
            Dim dashboard As New Dashboard()
            Dim objectDataSource As New DashboardObjectDataSource("Data Source 1")
            objectDataSource.DataSource = GetType(Data)
            objectDataSource.DataMember = "CreateData"
            dashboard.DataSources.Add(objectDataSource)

            ' Creates a Pie dashboard item that displays share of sold units quantity per sales person.
            Dim pies As New PieDashboardItem()
            pies.DataSource = dashboard.DataSources(0)
            Dim salesPersonArgument As New Dimension("SalesPerson")
            Dim quantity As New Measure("Quantity")
            pies.Arguments.Add(salesPersonArgument)
            salesPersonArgument.TopNOptions.Enabled = True
            salesPersonArgument.TopNOptions.Count = 3
            salesPersonArgument.TopNOptions.Measure = quantity
            pies.Values.Add(quantity)

            ' Creates a Grid dashboard item that displays sales persons and corresponding quantities.
            Dim grid As New GridDashboardItem()
            grid.DataSource = dashboard.DataSources(0)
            grid.Columns.Add(New GridDimensionColumn(New Dimension("SalesPerson")))
            grid.Columns.Add(New GridMeasureColumn(New Measure("Quantity")))

            dashboard.Items.AddRange(pies, grid)
            dashboardViewer1.Dashboard = dashboard
        End Sub

        ' Handles the DashboardViewer.DataLoading event to provide the dashboard with new data.
        Private Sub dashboardViewer1_DataLoading(ByVal sender As Object, ByVal e As DataLoadingEventArgs) _
            Handles dashboardViewer1.DataLoading
            If e.DataSourceName = "Data Source 1" Then
                e.Data = Data.CreateData()
            End If
        End Sub

        Private Sub button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles button1.Click
            ' Reloads data in data sources.
            dashboardViewer1.ReloadData()
        End Sub
    End Class
End Namespace

Data.vb

Imports System
Imports System.Collections.Generic
Imports System.Threading

Namespace Dashboard_BindingToList
    Public Class Data
        Public Property SalesPerson() As String
        Public Property Quantity() As Integer

        Public Shared Function CreateData() As List(Of Data)

            Dim data_Renamed As New List(Of Data)()
            Dim salesPersons() As String = {"Andrew Fuller", "Michael Suyama",
                                            "Robert King", "Nancy Davolio",
                                            "Margaret Peacock", "Laura Callahan",
                                            "Steven Buchanan", "Janet Leverling"}

            For i As Integer = 0 To 99
                Dim record As New Data()
                Dim seed As Long = CLng(Date.Now.Ticks) And &HFFFF
                record.SalesPerson = salesPersons((New Random(seed)).Next(0, salesPersons.Length))
                record.Quantity = (New Random(seed)).Next(0, 100)
                data_Renamed.Add(record)
                Thread.Sleep(3)
            Next i
            Return data_Renamed
        End Function
    End Class
End Namespace

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the DataLoading event.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

how-to-bind-a-dashboard-to-a-dataset-populated-from-an-xml-file-e4857/CS/Dashboard_DataLoading_Example/Form1.cs#L16

    dashboardViewer1.Dashboard = new Dashboard1();
    dashboardViewer1.DataLoading += DashboardViewer1_DataLoading;
}

winforms-dashboard-add-custom-interactivity-to-dashboard/CS/Dashboard_CustomVisualInteractivity/Form1.cs#L13

InitializeComponent();
dashboardViewer1.DataLoading += dashboardViewer1_DataLoading;
dashboardViewer1.DashboardItemClick += dashboardViewer1_DashboardItemClick;

VB.NET

how-to-bind-a-dashboard-to-a-dataset-populated-from-an-xml-file-e4857/VB/Dashboard_DataLoading_Example/Form1.vb#L16

    dashboardViewer1.Dashboard = New Dashboard1()
    AddHandler dashboardViewer1.DataLoading, AddressOf DashboardViewer1_DataLoading
End Sub

winforms-dashboard-add-custom-interactivity-to-dashboard/VB/Dashboard_CustomVisualInteractivity/Form1.vb#L14

InitializeComponent()
AddHandler dashboardViewer1.DataLoading, AddressOf dashboardViewer1_DataLoading
AddHandler dashboardViewer1.DashboardItemClick, AddressOf dashboardViewer1_DashboardItemClick