ASPxTrackBar.PositionStart Property

Gets or sets main drag handle position.

Namespace: DevExpress.Web

Assembly: DevExpress.Web.v20.2.dll

NuGet Package: DevExpress.Web

Declaration

C#

[DefaultValue(typeof(decimal), "0")]
public decimal PositionStart { get; set; }

VB.NET

<DefaultValue(GetType(Decimal), "0")>
Public Property PositionStart As Decimal

Property Value

Type	Default	Description
Decimal	"0"	A Decimal value that specifies main drag handle position.

Remarks

When the ASPxTrackBar.AllowRangeSelection property is set to true a track bar displays two drag handles to support the value range selection. In this case, the PositionStart property specifies the position of the main drag handle. To specify the secondary drag handle position, use the ASPxTrackBar.PositionEnd property. If the AllowRangeSelection property is set to false you can specify the position of the single drag handle using the ASPxTrackBar.Position property.

If the ASPxTrackBar.Items collection is specified, the PositionStart property returns a zero-based index of an item where the main drag handle is placed. If the Items collection is empty, the PositionStart property is equal to the item’s TrackBarItem.Value property.

The available range of values the PositionStart property is determined by the ASPxTrackBar.MinValue and ASPxTrackBar.MaxValue property values.

Example

The code sample below demonstrates how you can use the ASPxTrackBar control to specify a filter condition for the ASPxGridView control.

Handle the ASPxClientTrackBar.PositionChanging event to update label content that displays the currently selected range. The ASPxClientTrackBar.PositionChanged event handler applies the specified filter to the grid by using the ASPxClientGridView.ApplyFilter method. Note that the ASPxTrackBar.ValueChangedDelay property specifies the time interval between when a user changes the editor’s value and when the filter is applied.

The image below shows the result.

JS

function initLbRange() {
     lbRange.SetText('$' + tbSale.GetPositionStart() + ',000 - $' + tbSale.GetPositionEnd() + ',000');
     updateGrid();
};

function updateLbRange(s, e) {
     lbRange.SetText('$' + e.newPositionStart + ',000 - $' + e.newPositionEnd + ',000');
};

function updateGrid() {
     var filterCondition = "[Sale] > " + tbSale.GetPositionStart() * 1000 
     + " AND [Sale] < " + tbSale.GetPositionEnd() * 1000;
     grid.ApplyFilter(filterCondition);
};

ASPX

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" Theme="Glass"%>

...

<dx:ASPxTrackBar ID="TbSale" runat="server" AllowRangeSelection="True" 
     LargeTickInterval="100" MaxValue="500" MinValue="100" PositionEnd="500" 
     PositionStart="100" ScalePosition="LeftOrTop" Step="10" 
     ClientInstanceName="tbSale" LargeTickEndValue="500" LargeTickStartValue="100" 
     ValueChangedDelay="1000" ValueToolTipPosition="None" Width="300px">
     <ClientSideEvents Init="initLbRange" PositionChanging="updateLbRange" 
          PositionChanged="updateGrid" />
</dx:ASPxTrackBar>

<dx:ASPxLabel ID="LbRange" runat="server" Text="" ClientInstanceName="lbRange">
</dx:ASPxLabel>

<dx:ASPxGridView ID="Grid" runat="server" AutoGenerateColumns="False" 
     DataSourceID="AccessDataSource1" ClientInstanceName="grid">
     <Columns>
          <dx:GridViewDataTextColumn FieldName="TitleOfCourtesy" VisibleIndex="0">
          </dx:GridViewDataTextColumn>
          <dx:GridViewDataTextColumn FieldName="FirstName" VisibleIndex="1">
          </dx:GridViewDataTextColumn>
          <dx:GridViewDataTextColumn FieldName="LastName" VisibleIndex="2">
          </dx:GridViewDataTextColumn>
          <dx:GridViewDataTextColumn FieldName="Sale" VisibleIndex="3">
               <PropertiesTextEdit DisplayFormatString="c" />
          </dx:GridViewDataTextColumn>
     </Columns>
</dx:ASPxGridView>

<asp:AccessDataSource ID="AccessDataSource1" runat="server" 
     DataFile="~/App_Data/Employees.mdb" 
     SelectCommand="SELECT [TitleOfCourtesy], [FirstName], [LastName], [Sale] FROM [Employees]">
</asp:AccessDataSource>