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Listbox with doubleclick event (one-click event fires BEFORE double-click event, messing it up)

Greetings..

I've successfully made a doubleclick event on a listbox, but with one annoying issue i cannot bare with:

The "single-click" event fires first (when i select an listitem) so that the double-click event doesn't work until the second time i double-click the listitem. See code below.

/// CODE I PAGE LOAD.
 
lbAllTemplateTasks.Attributes.Add("ondblclick", ClientScript.GetPostBackEventReference(lbAllTemplateTasks, "addthis"));
 
if (Request["__EVENTARGUMENT"] != null && Request["__EVENTARGUMENT"] == "addthis")
        {
            if (lbAllTemplateTasks.SelectedIndex > -1)
            {
                TemplateTask tt = TemplateTask.TryFind(Convert.ToInt32(lbAllTemplateTasks.SelectedValue));
                Stage stage = Stage.Find(Convert.ToInt32(ddlSelectStage.SelectedValue));
 
                stage.TemplateTaskList.Add(tt);
                stage.SaveAndFlush();
            }
 
            lbAllTemplateTasks.DataBind();
            lbThisTemplateTasks.DataBind();
            upnlAllTemplateTasks.Update();
            upnlThisTemplateTasks.Update();
        }

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apresto

You can disable the onclick event by using the -= syntax to remove the handler and reapplying it when it is ok for it to fire

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apresto

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Nygter

ASKER

Aah.. thank you for this Apresto !.. Most useful !..

Since i have to use the eventhandling many places i've made my own listboxcontrol which extends Listbox and implements IPostBackEventHandler.

Only issue is that it fires on the _CLICK_ event.. not the _DOUBLE_CLICK_.. weird..

It works marvelously, but.. it does the moving on the click event, not the doubleclick :)

Care to take a quick look ?

LISTBOXCONTROL : 
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Text;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.Design.WebControls;
 
namespace Induct_Ctl
{
    public class InductListBox : ListBox,IPostBackEventHandler
    {
        public event EventHandler DoubleClick;
 
        protected virtual void OnDoubleClick(EventArgs e)
        {   
            if(DoubleClick != null)   
            {      
                DoubleClick(this, e);   
            }
        }
 
        public void RaisePostBackEvent(string navigateUrl) 
        { 
            this.OnDoubleClick(System.EventArgs.Empty); 
        }
 
        protected override void OnPreRender(EventArgs e) 
        { 
            base.OnPreRender(e); this.Attributes.Add("ondblclick", "javascript: " + Page.GetPostBackEventReference(this)); 
        }
 
    }
}
 
 
Usage : 
protected void lnkSetTemplateTask_Click(object sender, ImageClickEventArgs e)
    {
        if (lbAllTemplateTasks.SelectedIndex > -1)
        {
            addTemplateTask();
        }
    }
 
<Induct:InductListBox ID="lbThisTemplateTasks" runat="server" 
                                                        DataSourceID="odsExistingTemplateTasks" DataTextField="Title" DataValueField="Id" 
                                                        Height="120px" Width="210px" AutoPostBack="True" 
                                                        onselectedindexchanged="lbThisTemplateTasks_SelectedIndexChanged" OnDoubleClick="lbThisTemplateTasks_DoubleClick" 
                                                        />

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