Filtering Data on a DevExpress GridView - vb.net

Question

I am an MVC person, and have minimal experience with WebForms, but now I am having to add some functionality to a legacy VB.NET WebForms application.
So the application is using DevExpress Grids, and it displays a really long grid view on the page where one of the columns has the following:
The extra functionality that I am asked to add is a filter where the user can say:
I only want to see the rows where the on-load radio button selected is Print (or one of the other two actions).
So I went to the bottom of the grid and created the following:
My thinking was, the user can come to this drop down and selected what he or she wants to filter on for radio button actions.
DevExpress GridView Code
<dx:ASPxGridView ID="GridView1" runat="server" Theme="Office2010Blue" KeyFieldName="ID" AutoGenerateColumns="False" DataSourceID="ObjectDataSource1" Width="3200px">
<Columns>
<!-- Many more columns go here -->
<dx:GridViewDataColumn Caption="" VisibleIndex="29" Name="decision" Width="150px">
<HeaderTemplate>
<asp:LinkButton runat="server" ID="lnkPrint" OnClick="SelectPrintAll">Print All</asp:LinkButton>
<asp:LinkButton runat="server" ID="lnkEmail" OnClick="SelectEmailAll">Email All</asp:LinkButton>
<asp:LinkButton runat="server" ID="lnkIgnore" OnClick="SelectIgnoreAll">Ignore All</asp:LinkButton>
</HeaderTemplate>
<DataItemTemplate>
<asp:UpdatePanel runat="server" ID="upRadDecision" UpdateMode="Conditional">
<ContentTemplate>
<dx:ASPxRadioButtonList ID="radDecision" runat="server" RepeatDirection="Horizontal"
OnSelectedIndexChanged="StoreDecisionForRow" AutoPostBack="True" Height="15px"
OnDataBinding="BindDecisionRadioButton">
<Border BorderStyle="None"></Border>
<Paddings Padding="0"></Paddings>
<Items>
<dx:ListEditItem Text="Print" Value="Print" />
<dx:ListEditItem Text="Email" Value="Email" />
<dx:ListEditItem Text="Ignore" Value="Ignore" />
</Items>
</dx:ASPxRadioButtonList>
</ContentTemplate>
</asp:UpdatePanel>
</DataItemTemplate>
<Settings HeaderFilterMode="CheckedList"></Settings>
</dx:GridViewDataColumn>
</Columns>
<!-- Stylres -->
<Styles>
<AlternatingRow Enabled="true" />
</Styles>
<!-- Settings -->
<Settings ShowFilterRow="True" ShowFilterRowMenu="true" ShowFilterBar="Auto" ShowHeaderFilterButton="true" ShowGroupPanel="True" ShowFooter="True" />
<SettingsBehavior AllowSelectByRowClick="False" />
<SettingsBehavior AllowSelectSingleRowOnly="False" />
<SettingsBehavior ProcessSelectionChangedOnServer="true" />
<SettingsPager Mode="ShowAllRecords" />
<GroupSummary>
<dx:ASPxSummaryItem SummaryType="Count" />
</GroupSummary>
</dx:ASPxGridView>
I have added a click handler to my filter button, and the code is like so:
Private Sub btnFilterDefaults_Click(sender As Object, e As EventArgs) Handles btnFilterDefaults.Click
Dim filterOn As String = ddDefaultsFilterOption.SelectedValue
'Code Handling the Filtering.
GridView1.filter
For rowIndex As Integer = 0 To GridView1.VisibleRowCount - 1
Dim datarow = GridView1.GetDataRow(rowIndex)
Dim radDecision As ASPxRadioButtonList = CType(GridView1.FindRowCellTemplateControl(rowIndex, Nothing, "radDecision"), ASPxRadioButtonList)
Dim decision As String = ""
If radDecision.Value Is Nothing then Continue For
decision = radDecision.Value.ToString()
If decision.Contains(filterOn) Then
datarow.?? <<<<< no option to hide row here!!! :/
End If
Next
End Sub
I was hoping that when I got hold of the data row, I'd be able to hide it, but there is no such option!

Answer 1

I think the issue is you're trying to apply a visible trait to a datarow. What you want to do is use GridViewRow instead. It's the presentation object. Sorry I don't have an example for you but here is a link to msdn for it

Answer 2

Did you try to use HeaderFilterMode for your GridView? This function started from 12 DevExpress version, as I remember. Look at the example below, how you can enable it.
<dx:GridViewDataColumn Caption="" VisibleIndex="29" Name="decision" Width="150px">
...
<Settings HeaderFilterMode="CheckedList" />
</dx:GridViewDataColumn>
If you have older version or you need completely another functionality, you can create your own custom template for filter column. Look at the example on c# below
public class FilterLookupTemplate : ITemplate
{
private const string FormatFilterValue = "FilterLookupTemplateValue_{0}";
public string ClientIdLookup { get; private set; }
public string FieldName { get; set; }
public string DataSourceID { get; set; }
public ASPxGridView GridView { get; set; }
#region ITemplate Members
/// <summary>
/// Initialization template
/// </summary>
public void Init()
{
(GridView != null).Ensure<ArgumentException>("There didn't passed reference to grid view!");
if (!GridView.IsClientSideAPIEnabled() || String.IsNullOrEmpty(GridView.ClientInstanceName))
{
GridView.ClientInstanceName = GridView.ID;
}
var column = GridView.Columns[FieldName] as GridViewDataColumn;
(column != null).Ensure<ArgumentException>("There is error to get column by name!");
column.Settings.ShowFilterRowMenu = DefaultBoolean.False;
GridView.AutoFilterCellEditorCreate += OnAutoFilterCellEditorCreate;
GridView.AutoFilterCellEditorInitialize += OnAutoFilterCellEditorInitialize;
GridView.ProcessColumnAutoFilter += OnProcessColumnAutoFilter;
}
/// <summary>
/// Creating filter dropdown control
/// </summary>
/// <param name="sender">Event sender</param>
/// <param name="e">Event arguments</param>
private void OnAutoFilterCellEditorCreate(object sender, ASPxGridViewEditorCreateEventArgs e)
{
if (e.Column.FieldName.Equals(FieldName))
{
var dde = new DropDownEditProperties { EnableClientSideAPI = true, DropDownWindowTemplate = this };
e.EditorProperties = dde;
}
}
/// <summary>
/// Initializing filter dropdown control
/// </summary>
/// <param name="sender">Event sender</param>
/// <param name="e">Event arguments</param>
private void OnAutoFilterCellEditorInitialize(object sender, ASPxGridViewEditorEventArgs e)
{
if (e.Column.FieldName.Equals(FieldName))
{
var editor = e.Editor as ASPxDropDownEdit;
(editor != null).Ensure<ArgumentException>("There wasn't passed reference to the drop down editor!");
editor.ReadOnly = true
}
}
/// <summary>
/// Processing column filtering
/// </summary>
/// <param name="sender">Event sender</param>
/// <param name="e">Event arguments</param>
private void OnProcessColumnAutoFilter(object sender, ASPxGridViewAutoFilterEventArgs e)
{
var session = GridView.Page.Session;
if (e.Kind == GridViewAutoFilterEventKind.CreateCriteria)
{
session[String.Format(FormatFilterValue, e.Column.FieldName)] = e.Value;
if (e.Column.FieldName.Equals(FieldName) && !String.IsNullOrEmpty(e.Value))
{
var values = e.Value.Split(new[] { ";" }, StringSplitOptions.RemoveEmptyEntries);
if (values.Length > 0)
{
var action = new Func<string, string, FunctionOperator>((name, value) =>
new FunctionOperator(FunctionOperatorType.Contains, new OperandProperty(name), new OperandValue(value)));
if (values.Length > 1)
{
var group = new GroupOperator(GroupOperatorType.Or);
group.Operands.AddRange(values.Select(v => action(e.Column.FieldName, v)).ToArray());
e.Criteria = group;
}
else
{
e.Criteria = action(e.Column.FieldName, values[0]);
}
}
}
}
else
{
if (session[String.Format(FormatFilterValue, e.Column.FieldName)] != null)
{
e.Value = session[String.Format(FormatFilterValue, e.Column.FieldName)].ToString();
}
}
}
/// <summary>
/// Rendering loolup template controls
/// </summary>
/// <param name="container">Container of date range template</param>
public void InstantiateIn(Control container)
{
(GridView != null).Ensure<ArgumentException>("There didn't passed reference to grid view!");
var table = new Table { Width = new Unit(200, UnitType.Pixel) };
container.Controls.Add(table);
var row = new TableRow();
table.Rows.Add(row);
var cell = new TableCell();
row.Cells.Add(cell);
var lbl = new ASPxLabel { ID = "lblSelect", Text = MessageResources.FilterLookupTemplate_SelectLabelText };
cell.Controls.Add(lbl);
cell = new TableCell();
row.Cells.Add(cell);
var lookup = new ASPxGridLookup
{
ID = GridView.ID + "lookupValues",
EnableClientSideAPI = true,
Width = new Unit(100, UnitType.Percentage),
SelectionMode = GridLookupSelectionMode.Multiple
};
lookup.GridView.Width = new Unit(100, UnitType.Percentage);
lookup.GridView.DataSourceID = DataSourceID;
lookup.GridView.KeyFieldName = "id";
lookup.GridView.Columns.Add(new GridViewCommandColumn { ShowSelectCheckbox = true, AllowDragDrop = DefaultBoolean.False });
var nameColumn = new GridViewDataTextColumn { FieldName = "name" };
nameColumn.Settings.AllowDragDrop = DefaultBoolean.False;
nameColumn.Settings.AllowGroup = DefaultBoolean.False;
nameColumn.Settings.AllowHeaderFilter = DefaultBoolean.False;
nameColumn.Settings.AllowSort = DefaultBoolean.False;
lookup.GridView.Columns.Add(nameColumn);
lookup.EnableClientSideAPI = true;
cell.Controls.Add(lookup);
ClientIdLookup = lookup.ClientID;
row = new TableRow();
table.Rows.Add(row);
cell = new TableCell { ColumnSpan = 2 };
row.Cells.Add(cell);
var lnk = new ASPxHyperLink { Text = MessageResources.FilterLookupTemplate_ApplyLinkText, NavigateUrl = "#" };
lnk.ClientSideEvents.Click =
String.Format("function (s, e) {{ {0}.HideDropDown(); ApplyLookupFilter({0}, {1}, '{2}', {3}); }}",
container.NamingContainer.NamingContainer.ClientID,
GridView.ClientInstanceName,
FieldName,
ClientIdLookup);
cell.Controls.Add(lnk);
container.Controls.Add(table);
}
#endregion
}
and then register it for your grid view. ReportsCustomerDataSource is a LINQ data source control.
public partial class YourPage: Page
{
protected override void OnInit(EventArgs e)
{
base.OnInit(e);
new FilterLookupTemplate { FieldName = "ReportCustomers", DataSourceID = ReportsCustomerDataSource.ID, GridView = _gridView }.Init();
}
}
On the form it will be look like that