setting the needle

[Harry]

Hi all

We have a large asp.net web application that was not built as a silverlight application.  We recently found that we will need to add use a silverlight rad gauge to our existing application.  I can get the gauge into the page without a problem and set the needle to a number in the xaml.cs file but I cannot set the needle outside of the control due to the application is not originally a silverlight build.  It is not really an option to rebuild the application because of the man hours involved.  If any body has any ideas to get the info to the control We would be very thankful.

[Andrey]

Hi Harry,

You can pass parameters to the Silverlight control using the user-defined initialization parameters for Silverlight Plug-in Object. The sample code below passes the needle value to the Silverlight user control.

<object data="data:application/x-silverlight-2," type="application/x-silverlight-2" width="100%" height="100%">
  <param name="initparams" value="needleValue=25"/>
  <param name="source" value="ClientBin/RadControlsSilverlightApp1.xap"/>
  <param name="onError" value="onSilverlightError" />
  <param name="background" value="white" />
  <param name="minRuntimeVersion" value="4.0.50826.0" />
  <param name="autoUpgrade" value="true" />
  <param name="onload" value="pluginLoaded" />
  <a href="http://go.microsoft.com/fwlink/?LinkID=149156&v=4.0.50826.0" style="text-decoration:none">
      <img src="http://go.microsoft.com/fwlink/?LinkId=161376" alt="Get Microsoft Silverlight" style="border-style:none"/>
  </a>
</object>

<UserControl x:Class="RadControlsSilverlightApp1.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"
    mc:Ignorable="d" d:DesignWidth="640" d:DesignHeight="480">
    <Grid x:Name="LayoutRoot">
        <telerik:RadGauge Height="200" Width="200">
            <telerik:RadialGauge>
                <telerik:RadialScale>
                    <telerik:IndicatorList>
                        <telerik:Needle Name="Needle1" />
                    </telerik:IndicatorList>
                </telerik:RadialScale>
            </telerik:RadialGauge>
        </telerik:RadGauge>
    </Grid>
</UserControl>

using System.Globalization;
using System.Windows;
using System.Windows.Controls;

namespace RadControlsSilverlightApp1
{
    public partial class MainPage : UserControl
    {
        public MainPage()
        {
            InitializeComponent();

            string stringValue = Application.Current.Host.InitParams["needleValue"];
            double value = double.Parse(stringValue, CultureInfo.InvariantCulture);

            this.Needle1.Value = value;
        }
    }
}

For more information please take a look to the following articles:
http://msdn.microsoft.com/en-us/library/cc838255(v=vs.95).aspx
http://msdn.microsoft.com/en-us/library/cc645076(v=vs.95).aspx

Best wishes,
Andrey Murzov
the Telerik team

[Jonathan]

How would you set the needle from the .cs file of an aspx page that hosts the silverlight control rather than using an object parameter?

[Andrey]

Hello Jonathan,

I have attached a sample solution that sets the needle value from the .cs file of an aspx page.

I hope it helps.


Kind regards,
Andrey Murzov
the Telerik team

[Jonathan]

thanks Andrey I'll take a look

[Jonathan]

I took a look at the example project and it works well for setting the intial value.  What I would liek to do is set the valuse every 5 minutes using a timer in the radajax manager.

<telerik:RadAjaxManager ID="RadAjaxManager1" runat="server">

        <AjaxSettings>

            <telerik:AjaxSetting AjaxControlID="Timer1">

                <UpdatedControls>

                    <telerik:AjaxUpdatedControl ControlID="RadRotator1" LoadingPanelID="RadAjaxLoadingPanel1" />

                    <telerik:AjaxUpdatedControl ControlID="radGridWhosCallingStats" LoadingPanelID="RadAjaxLoadingPanel1" />

                    <telerik:AjaxUpdatedControl ControlID="gaugeUserControl1" LoadingPanelID="RadAjaxLoadingPanel1" />                    

                </UpdatedControls>

            </telerik:AjaxSetting>

        </AjaxSettings>

    </telerik:RadAjaxManager>

    <telerik:RadAjaxLoadingPanel ID="RadAjaxLoadingPanel1" runat="server" InitialDelayTime="100" BackgroundPosition="Bottom" Transparency="10" >

            <img src="./images/loading7.gif" alt="Loading..." style="border: 0;"/>

     </telerik:RadAjaxLoadingPanel> 

    <asp:Panel ID="Panel1" runat="server">

        <asp:Timer ID="Timer1" runat="server" ontick="Timer1_Tick"/>

    </asp:Panel>

The problem is that it looks like the gauge control value is set with a piece of javascript that is not updated by the timer.  how might I accomplish this?

Thanks,
Jonathan

[Jonathan]

Hello again.

basically the guage user control does a

 

Page.ClientScript.RegisterStartupScript(

 

typeof(Page), "SLPROXY_VALUE" + this.ClientID, string.Format("setGaugeValue('{0}','{1}');", this.GaugeValue, this.ClientID), true);

which inserts the follwoing piece of code into the page on the initial page load

 

//<![CDATA
setGaugeValue('71','ctl00_ContentPlaceHolder1_gaugeUserControl1');

but I'd like to be able to reset the gauge value via the ajax callback from the timer every 5 minutes based on a value returned from a webservice call.  It's a fine piece of work so far could you help me with this last piece.

I'm wondering if using a literal and putting the javascript code in the literal and then having one of the updated controls in the ajax manager be the literal might work.. thoughts?

[Andrey]

Hello Jonathan,

You can take advantage of the RadAjaxManager.ResponseScripts property, as shown in this example.

Best regards,
Ves
the Telerik team

[Jonathan]

Thanks, but how would I access the page's radajaxmanager or in the case of your example a radajaxpanel from inside the usercontrol Page_load event as this is where the script is setup?

Cheers
Jonathan

[Giuseppe]

Hello Jonathan,

Check the following help topic here:

If one still needs the manager instance at the code of a WebUserControl for example so that an AJAX request need to be triggered explicitly, she can get the manager by RadAjaxManager.GetCurrent() method call. The method will return null if there is no manager on the page, similar to ASP:ScriptManager implementation.


Regards,
Giuseppe
the Telerik team

[Jonathan]

ok this is making my brain hurt.    I can see how having a timer inside the user control and using the ajax proxy and RadAjaxManager.ResponseScripts to repond to the ajaxyified timer click to set the scriptabel value on the silverlight object would probably work,  but the timer is in the main page that holds the usercontrol and that leaves me a bit stumped how to pull al this together... 

[Giuseppe]

Hi Jonathan,

It is possible to get a reference to the Timer from the user control like this:

public partial class WebUserControl : System.Web.UI.UserControl
{
    private Timer Timer
    {
        get
        {
            return this.Page.FindControl("Timer1") as Timer;
        }
    }

    protected void Page_Load(object sender, EventArgs e)
    {
        if (this.Timer != null)
        {
            this.Timer.Tick += new EventHandler<EventArgs>(timer_Tick);
            this.Unload += new EventHandler(WebUserControl_Unload);
        }
    }

    void WebUserControl_Unload(object sender, EventArgs e)
    {
        if (this.Timer != null)
            this.Timer.Tick -= new EventHandler<EventArgs>(timer_Tick);
    }

    void timer_Tick(object sender, EventArgs e)
    {
        // ...
    }
}

All the best,
Giuseppe
the Telerik team