ASPxTrackBar.ShowDragHandles Property

Gets or sets the value that specifies whether or not main and secondary drag handles are shown.

Namespace: DevExpress.Web

Assembly: DevExpress.Web.v24.1.dll

NuGet Package: DevExpress.Web

Declaration

C#

[DefaultValue(true)]
public bool ShowDragHandles { get; set; }

VB.NET

<DefaultValue(True)>
Public Property ShowDragHandles As Boolean

Property Value

Type	Default	Description
Boolean	true	true to show drag handles; otherwise, false.

Remarks

This property is a wrapper of the TrackBarProperties.ShowDragHandles property.

Example

The code sample below demonstrates how you can use the ASPxTrackBar control in two ways. On the one hand, a user can easily choose the required value or item, on the other hand, you can show end-users the visual result of their actions.

In this example, an end-user can select a chemical element and see its melting point. Here we use two track bars. The first track bar is used to visualize melting points and looks like a thermometer scale. By design, an end-user cannot change its value directly, so the ASPxEdit.ReadOnly property for this track bar is enabled. The second track bar is used to select the required chemical element. All the defined elements are gathered to the ASPxTrackBar.Items collection. The ASPxClientTrackBar.PositionChanged event of the second track bar is handled to update the value of the first track bar.

The image below shows the result.

JS

function OnPositionChanged(s, e) {
    updateItems(s);
}

function OnInit(s, e) {
    updateItems(s);
}

function updateItems(trackBar) {
    var trackBarValue = trackBar.GetValue();
    termometer.SetValue(trackBarValue);
}

ASPX

<dx:ASPxTrackBar ID="ASPxTrackBar1" runat="server" ScalePosition="RightOrBottom" 
    Orientation="Vertical" ShowChangeButtons="False" 
    ShowDragHandles="False" Direction="Reversed" ReadOnly="True" 
    ValueType="System.String" ClientInstanceName="termometer" 
    MaxValue="-340" MinValue="-440" ScaleLabelFormatString="{0}°F" 
    Width="54px" ValueToolTipPosition="None" LargeTickEndValue="-340" 
    LargeTickStartValue="-440" Position="-440" PositionEnd="-440" PositionStart="-440" 
    >
    <ScaleStyle>
        <BackgroundImage ImageUrl="~/imgs/scale_background.png" />
    </ScaleStyle>
    <BarHighlightStyle>
        <BackgroundImage ImageUrl="~/imgs/barhighlight.png" Repeat="RepeatY" 
            HorizontalPosition="center" />
    </BarHighlightStyle>
    <TrackStyle>
        <BackgroundImage ImageUrl="~/imgs/track.png" Repeat="RepeatY" 
            HorizontalPosition="center" />
    </TrackStyle>
</dx:ASPxTrackBar>


<br />


<dx:ASPxTrackBar ID="ASPxTrackBar2" runat="server" LargeTickEndValue="4" 
    MaxValue="4" Step="1" ScalePosition="RightOrBottom" 
    ShowChangeButtons="False" ValueType="System.String" Position="0" 
    PositionStart="0" EnableAnimation="true" 
    ValueToolTipPosition="RightOrBottom" >
    <ClientSideEvents  Init="OnInit" PositionChanged="OnPositionChanged" />
    <Items>
        <dx:TrackBarItem Text="H" ToolTip="Hydrogen" Value="-434" />
        <dx:TrackBarItem Text="Ne" ToolTip="Neon" Value="-414"/>
        <dx:TrackBarItem Text="O" ToolTip="Oxygen" Value="-367"/>
        <dx:TrackBarItem Text="F" ToolTip="Fluorine" Value="-362"/>
        <dx:TrackBarItem Text="N" ToolTip="Nitrogen" Value="-346"/>
    </Items>
    <ScaleStyle Font-Names="Arial" >
    </ScaleStyle>
</dx:ASPxTrackBar>