<

Go Premium for a chance to win a PS4. Enter to Win

x

Working with Modal Popup extender control.

Published on
48,371 Points
38,471 Views
4 Endorsements
Last Modified:
Awarded
This article discusses the ASP.NET AJAX ModalPopupExtender control. In this article we will show how to use the ModalPopupExtender control, how to display/show/call the ASP.NET AJAX ModalPopupExtender control from javascript, how to show/display/call the modal popup from a hyper link control within the gridview control and finally some important javascript methods of the ASP.NET AJAX ModalPopupExtender control. So first let's see how to use the ModalPopupExtender control.

How to use the ASP.NET AJAX ModalPopupExtender control?

Drag and drop a ASP.NET button/LinkButton/ImageButton or any control to an aspx page. To add a ModalPopupExtender control, drag and drop the control from the toolbox or Select the control (button/LinkButton/ImageButton or any other control) and click the button with a greater than symbol as shown below.
image-thumb11.png
When you click the arrow you will get a menu with an “Add Extender” option as shown below.
image-thumb10.png
Click the “Add Extender” menu option and select “ModalPopupExtender” from “Extender Wizard” popup. Once you have added the ModalPopupExtender control you need an ASP.NET panel control. This is because the ModalPopupExtender control will show the content of the Panel control as a popup. Add ASP.NET Panel control and the content which you want to display as popup into the ASP.NET Panel control. Sample code with all the above requirement is pasted below. Don’t forget to drag and drop the ScriptManager control to the page.
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="ModalPopup.aspx.cs" Inherits="ModalPopup" %> 
<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="cc1" %> 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml"> 
<head runat="server"> 
    <title>Modal Popup Demo</title> 
    <style> 
    .backgroundColor 
    { 
        background-color:Gray;    
        filter:alpha(opacity=25); 
    } 
    </style> 
</head> 
<body> 
    <form id="form1" runat="server"> 
    <div> 
        <asp:ScriptManager ID="ScriptManager1" runat="server"> 
        </asp:ScriptManager>        
        <asp:Button ID="popupBtn" runat="server" Text="Click to see the modal popup." /> 
        <asp:Panel ID="Panel1" runat="server" Style="display: none; padding:10px; border:1px; border-style:solid;" BackColor="#FF9933" Width="400px"> 
            <h3 style="text-align: center;" id="header">Modal Popup</h3> 
            <p>This is a Modal Popup extender control. You are seeing this because you have clicked the hyperlink button.</p> 
            <p style="text-align: center;"><asp:Button ID="closeBtn" runat="server" Text="Close" /></p>        
        </asp:Panel> 
        <cc1:ModalPopupExtender ID="ModalPopupExtender" runat="server" 
            TargetControlID="popupBtn" 
            PopupControlID="Panel1"              
            OkControlID="closeBtn" 
            BackgroundCssClass="backgroundColor" 
            DropShadow="true" 
            PopupDragHandleControlID="header"/> 
    </div> 
    </form> 
</body> 
</html>

Open in new window

From the above code one can see I have a ScriptManager, an asp:Button control, an asp:Panel control, some contents inside the panel control and then we have the ModalPopupExtender control. Normally when you attach an ASP.NET panel control to a ModalPopupExtender control it will become invisible in the HTML rendered to the browser and if due to some reason if the panel control is being displayed in the page then just set the "Style" property' “display” attribute to “none” as in the above e.g. Now when you click the button you will see a popup as shown below.
image-thumb2.png
Now let's see how to configure the ModalPopupExtender control. The configuration is pretty simple; you need to set some properties and and you will have your Modal popup. The properties are as follows

TargetControlID: This property specifies which control should be used as the source for showing the popup control i.e. on click of which control the popup should be displayed. In our e.g. we have given the TargetControlID as our button control. You can assign the ID of any ASP.NET controls like LinkButton, ImageButton, HyperLink, DropDownList, CheckBox, RadioButton etc. Even you can give a label’ id as the TargetControlID.

PopupControlID: The ID of the control to be displayed as a modal popup. In our example we have given ASP.NET panel control’ ID as the "PopupControlID". You can give any ASP.NET control’ ID. For example, if you give the ID of a textbox then the textbox alone will be popped up. It is not compulsory that you should provide an ASP.NET panel control.

OkControlID: The ID of the control which should act as an Ok button. Clicking of this control will dismiss the popup.

BackgroundCssClass: The name of the CSS class that needs to be applied to the background of the popup. One thing to note here is that if you don’t provide a CSS class then the modal popup will not function like a modal dialog; i.e. one will be able to interact with the controls in the back of the popup control, so it's imperative to provide a valid CSS class name value to the BackgroundCssClass property. In the above example we have defined a CSS class called “backgroundColor” in the header section of the aspx page. Please note in the CSS class definition we have applied “filter” property to make the background transparent.

DropShadow: Accepts a boolean value which specifies whether the popup should have shadow. True will give a shadow and false will disable the shadow.

PopupDragHandleControlID: The ID of the control clicking on which the ModalPopupExtender can be dragged. The control should be enclosed in the control specified using PopupControlID; i.e. in our case inside the ASP.NET panel control. If a particular control ID is set as the PopupDragHandlerControlID then one can click on that control and drag the ModalPopupExtender control. In the above example we have set the ID of the “h3” control as PopupDragHandleControlID. If anyone wants to drag the popup control then he needs to click "h3" and drag the popup control.

CancelControlID: If you want a button to behave as a Cancel button provide the ID of the button. This button will cancel the popup.

Drag: This property takes a boolean value that, when set, determines whether the popup control can have the drag feature. A value of true means the popup extender control can be dragged around the screen whereas false will disable the drag.

RepositionMode: This property accepts four values. They are “None”, “RepositionOnWindowResize”, “RepositionOnWindowResizeAndScroll” and “RepositionOnWindowScroll”. The default value is “RepositionOnWindowResizeAndScroll”. Explanation of each values is given below.

RepositionOnWindowResize: Will reposition the popup when the window is resized.

RepositionOnWindowScroll: Will reposition the popup when the scroll bar is moved.

RepositionOnWindowResizeAndScroll: Will reposition the popup when you resize or when you move the scroll bar. Its a combination of both “RepositionOnWindowResize” and “RepositionOnWindowScroll”.

None: The popup will not be tinkered with. It will be shown in its original position irrespective of window resizing or scroll bar being moved.

DynamicServicePath: Link to a webservice/aspx page from where data or content needs to be retrieved and displayed in the popup extender control.

DynamicServiceMethod: The method name from which content needs to be retrieved. The method can be a webservice method or a method in your code behind file of your aspx file. If you leave the “DynamicServicePath” empty and provide DynamicServiceMethod name then the system will try to ping the same page’ and try to find a method. We will see an e.g. with web service shortly.

DynamicContextKey: The string value which will be passed as the parameter to the method specified in DynamicServiceMethod. One thing to note here is that the parameter should be named contextKey in the webservice/code behind.

X: The X coordinates for the popup control.

Y: The Y coordinates for the popup control.

Showing the content of a webservice (asmx) method in a ModalPopupExtender control.

Showing the output of a web method of a web service in a ModalPopupExtender control is also pretty simple. First you need to have a web service, if you don’t have one it's very easy to create one in Visual Studio. Create a web service and add a method the output of which you want to display in a ModalPopupExtender conrol. Below I have pasted the code of my webservice.
using System; 
using System.Collections; 
using System.Linq; 
using System.Web; 
using System.Web.Services; 
using System.Web.Services.Protocols; 
using System.Xml.Linq; 
 
[WebService(Namespace = "http://tempuri.org/")] 
/*The below attribute is needed so that the webservice can process calls from ASP.NET AJAX controls. Without the below attribute one may get the following error. "Web Service call failed: 500"*/ 
[System.Web.Script.Services.ScriptService] 
public class Service : System.Web.Services.WebService 
{ 
    public Service () 
    { 
    } 
    /*Method which will be called by the ModalPopupExtender control.*/ 
    [WebMethod] 
    public string HelloWorld() 
    { 
        return "<b>Hello World</b><br/>"; 
    } 
}

Open in new window

The above webservice is pretty simple. It has only one web method -- the most famous of them all, the “HelloWorld” method. The method returns a HTML formatted “Hello World” string.

One thing to note while writing a web service whose methods can be called by the ASP.NET Ajax controls is that you need to add the “[System.Web.Script.Services.ScriptService]” attribute. If the before-mentioned attribute is not added then you may get the following web service error:
Web Service call failed: 500
The mark up for the ModalPopupExtender control to display the webservice’ web method output is pasted below.
<!--Web service content display demo--> 
<asp:Panel ID="webServicePanel" runat="server" Width="300px" Height="300" BackColor="Azure"> 
    <asp:Label ID="webServiceContentLbl" runat="server" Text="Label"></asp:Label> 
    <asp:Button ID="clsBtn" runat="server" Text="Button" /> 
</asp:Panel> 
<asp:Button ID="webServiceCall" runat="server" Text="Click to see the output of a webservice in a popup." /> 
<cc1:ModalPopupExtender ID="ModalPopupExtender1" runat="server" TargetControlID="webServiceCall" OkControlID="clsBtn" DynamicServicePath="Service.asmx" DynamicServiceMethod="HelloWorld"   DynamicControlID="webServiceContentLbl"  
  BackgroundCssClass="backgroundColor" PopupControlID="webServicePanel" DropShadow="true">        
</cc1:ModalPopupExtender>

Open in new window

The difference from our previous ModalPopupExtender control is that we have configured some extra properties related to webservice request. They are DynamicServicePath where we have given the URL of the web service. DynamicServiceMethod takes the web method name and finally DynamicControlID takes the ID of the control in which the output of the web method should be displayed. We have given the ID of the label control inside the panel control as the DynamicControlID. The label control will display “Hello World” string in bold.

The ModalPopupExtender is capable of displaying the output from normal aspx pages as well. To display some content it is not compulsory that you need to create a webservice. One can directly show the output of a method in a code behind file in a ModalPopupExtender. Let's see how to do that.
Displaying the content of a webpage (aspx) method in a ModalPopupExtender control.

Below is the code behind file content of the ASPX page. The code is pretty straightforward. It has a static method called HelloWorld that returns the same text as that of the webservice.
public partial class ModalPopup : System.Web.UI.Page 
{ 
    protected void Page_Load(object sender, EventArgs e) 
    { 
    } 
    /// <summary> 
    /// Page method which will be called by the modal popup extender control. 
    /// </summary> 
    /// <returns></returns> 
    [System.Web.Services.WebMethod(), System.Web.Script.Services.ScriptMethodAttribute()] 
    public static string HelloWorld() 
    { 
        return "<b>Hello World</b><br/>"; 
    } 
}

Open in new window

One thing to keep in mind when you declare a method in an aspx that needs to be accessed by the ModalPopupExtender control or any ASP.NET AJAX control is to apply the following attribute.
[System.Web.Services.WebMethod(), System.Web.Script.Services.ScriptMethodAttribute()]

Open in new window

In addition to the above method attributes one needs to declare the method as a static method. If the method is not declared static then you may not be able to ping from the client side. In the case of web service the method need not be static. Some of the errors you may face because of not declaring the method static or because of not applying the above attributes are listed below.
1. Web Service call failed: 12030
2. Web Service call failed: 500
If the above two errors popup you know what to do? First check whether the method attributes are applied and second, see to it that the method is declared as static in the code behind.

Below is the mark up needed to display the content from a method in an aspx page.
<!--Web service content display demo--> 
<asp:Panel ID="webServicePanel" runat="server" Width="300px" Height="300" BackColor="Azure"> 
    <asp:Label ID="outputContentLbl" runat="server" Text="Label"></asp:Label> 
    <asp:Button ID="clsBtn" runat="server" Text="Button" /> 
</asp:Panel> 
<asp:Button ID="webServiceCall" runat="server" Text="Click to see the output of a webservice in a popup." /> 
<cc1:ModalPopupExtender ID="ModalPopupExtender1"       runat="server"  DynamicServicePath="ModalPopup.aspx" 
    TargetControlID="webServiceCall"          OkControlID="clsBtn"          DynamicServiceMethod="HelloWorld"          DynamicControlID="outputContentLbl"          BackgroundCssClass="backgroundColor"          PopupControlID="webServicePanel" DropShadow="true">        
</cc1:ModalPopupExtender>

Open in new window

You can see in the above mark up everything is same except for the webservice related properties. DynamicServicePath is used to specify the url of the page. If left blank it will refer the same page. DynamicServiceMethod is the method name in the aspx/codebehind which will be pinged by the ModalPopupExtender to retrieve data. DynamicControlID is the ID of the control in which you would like to display the output of the method. DynamicControlID should have the ID of a control inside the ASP.NET Panel control in our case or any control inside whatever container control the user is making use for popup. Also if you have any argument then you can use DynamicContextKey to pass the string argument.

Hiding and Showing the ModalPopupExtender control using javascript

The above examples are quite straightforward and easy to implement. Unfortunately a developer’s life is not a bed of roses. There may arise a requirement where one has to call/show/hide the popup control using javascript. So let's see how to do exactly this. Below is the HTML markup.
<asp:Button ID="popupScriptBtn" runat="server" Text="Click to view the modal popup using javascript"   OnClientClick=”javascript:showModalPopup();return false;” /> 
<asp:Button ID="popupBtn" runat="server" Text="Click to see the modal popup." /> 
<div ID="div1" runat="server" > 
    <asp:Panel ID="Panel1" runat="server" Style="display: none; padding:10px; border:1px; border-style:solid;" BackColor="#FF9933" Width="400px"> 
        <table id="Table1" style="background-color: #C0C0C0; width: 400px; height: 5px;"><tr><td><h3 style="text-align: center;" id="header">Modal Popup</h3></td></tr></table> 
        <p>This is a Modal Popup extender control. You are seeing this because you have clicked the hyperlink button.</p> 
        <p style="text-align: center;"><asp:Button ID="closeBtn" runat="server" Text="Close" /></p>        
    </asp:Panel> 
</div> 
<cc1:ModalPopupExtender ID="ModalPopupExtender" runat="server" TargetControlID="popupBtn" 
    PopupControlID="Panel1" OkControlID="closeBtn" 
    BackgroundCssClass="backgroundColor" 
    DropShadow="true" PopupDragHandleControlID="header" 
    CancelControlID="" Drag="true" RepositionMode="None" />

Open in new window

The above markup is pretty much same as the one we used at the beginning of this article. The only difference is that we have an extra ASP.NET button that shows the ModalPopupExtender control with the help of javascript. In the above markup we have used the “OnClientClick” property to assign the javascript, showModalPopup, that needs to be called when the button is clicked. The javascript to show and hide the popup is pasted below.
<script type="text/javascript" language="javascript"> 
//Javascript function to hide the popup control. 
function closeModalPopup() 
{ 
    //Using the $find javascript method to retrieve the modal popup control. 
    var modalPopup = $find('<%=ModalPopupExtender.ClientID %>'); 
    if (modalPopup != null) 
    { 
        modalPopup.hide(); 
    } 
} 
//Javascript function to show the ModalPopupExtender control. 
function showModalPopup() 
{ 
    //Using the $find javascript method to retrieve the modal popup control. 
    var modalPopup = $find('<%=ModalPopupExtender.ClientID %>'); 
    if (modalPopup != null) 
    { 
        modalPopup.show(); 
    }    
} 
</script>

Open in new window

Note: <%=ModalPopupExtendender.ClientID%> will work only if you place the javascript code inside an aspx page. The same code if placed in an external JS file will throw error.
In the above javascript we have two functions. One to show the ModalPopupExtender control and another to hide the control. In both the functions we are using $find shortcut method to retrieve the popup control. To know more about $find method please see this link. Once we have retrieved the modal popup control we are calling the show and hide methods of the control to show and hide the control respectively.

Using the modal popup control within a GridView control

There is nothing different here. In a grid if you want to link the ModalPopupExtender to a control inside the GridView you need to just convert the column into a template column and add the ModalPopupExtender control to the column, and configure the necessary properties as discussed. Below is a sample code where I have added the ModalPopupExtender control in the header section as well in a column of GridView control.
<asp:GridView ID="backIssueGrid" runat="server" AutoGenerateColumns="False" 
            DataMember="issue" DataSourceID="backIssuesXML"> 
        <RowStyle BorderColor="Tan" BorderStyle="Solid" BorderWidth="1px" /> 
        <Columns> 
            <asp:TemplateField HeaderText="Back Issues" HeaderStyle-CssClass="headerText"> 
                <ItemTemplate> 
                    <asp:HyperLink ID="title" runat="server" 
                        Text='<%# XPath("@title") %>' CssClass="gridText" NavigateUrl='<%# XPath("url") %>'></asp:HyperLink> 
                    <asp:Panel ID="webServicePanel" runat="server" Width="300px" Height="300" BackColor="Azure"> 
                        <asp:Label ID="outputContentLbl" runat="server" Text="Label"></asp:Label> 
                        <asp:Button ID="clsBtn" runat="server" Text="Button" /> 
                    </asp:Panel> 
                    <cc1:ModalPopupExtender ID="ModalPopupExtender1" runat="server" DynamicServicePath="ModalPopup.aspx" 
                        TargetControlID="title" OkControlID="clsBtn" 
                        DynamicServiceMethod="HelloWorld" 
                        DynamicControlID="outputContentLbl"  
                        BackgroundCssClass="backgroundColor" PopupControlID="webServicePanel" 
                        DropShadow="true">        
                    </cc1:ModalPopupExtender> 
                </ItemTemplate> 
                <HeaderStyle CssClass="headerText"></HeaderStyle> 
                <ItemStyle BorderColor="Tan" BorderStyle="Solid" BorderWidth="1px" />                
            </asp:TemplateField> 
            <asp:TemplateField HeaderStyle-CssClass="headerText">                
                <ItemTemplate> 
                    <asp:TextBox ID="quantityTxt" Width="30" runat="server" Text='<%#XPath("@noOfCopies") %>' CssClass="gridText"></asp:TextBox> 
                </ItemTemplate> 
                <ItemStyle BorderColor="Tan" HorizontalAlign="Center" BorderStyle="Solid" BorderWidth="1px" /> 
                <HeaderStyle CssClass="headerText"></HeaderStyle> 
                <HeaderTemplate> 
                    <asp:ImageButton ID="ImageButton1" runat="server" ImageUrl="some.gif" />                    
                    <asp:Panel ID="webServicePanel2" runat="server" Width="300px" Height="300" BackColor="Azure"> 
                        <asp:Label ID="outputContentLbl1" runat="server" Text="Label"></asp:Label> 
                        <asp:Button ID="clsBtn" runat="server" Text="Button" /> 
                    </asp:Panel> 
                    <cc1:ModalPopupExtender ID="ModalPopupExtender2" runat="server" DynamicServicePath="ModalPopup.aspx" 
                        TargetControlID="ImageButton1" OkControlID="clsBtn" 
                        DynamicServiceMethod="HelloWorld" 
                        DynamicControlID="outputContentLbl1"  
                        BackgroundCssClass="backgroundColor" PopupControlID="webServicePanel2" 
                        DropShadow="true">        
                    </cc1:ModalPopupExtender> 
                </HeaderTemplate> 
            </asp:TemplateField> 
            <asp:TemplateField> 
                <ItemTemplate> 
                    <asp:Label ID="Label4" CssClass="gridText" runat="server" Text='<%# Add(XPath("@noOfCopies"), XPath("@price"))%>'></asp:Label> 
                </ItemTemplate> 
            </asp:TemplateField> 
            <asp:CommandField ShowSelectButton="True" ButtonType="Button" 
                SelectText="Remove" ControlStyle-CssClass="buttonText" > 
            <ControlStyle CssClass="buttonText"></ControlStyle> 
            <ItemStyle BorderColor="Tan" BorderStyle="Solid" BorderWidth="1px" /> 
            </asp:CommandField> 
        </Columns> 
        <EditRowStyle BorderStyle="Solid" /> 
    </asp:GridView>

Open in new window

In the above example you can see in the markups that in the first portion I have placed a popup control in the “ItemTemplate” and hooked the ModalPopupExtender control to a hyperlink control. Pretty simple, isn’t it? In the second section I have put the popup control in the HeaderTemplate of the column and hooked it to a ImageButton. So when one clicks on the image button in the header he will see a popup. If you want you can add javascript “onmouseover” and “onmouseout” behavior to the image in the code behind by adding attributes to the ImageButton control.

In my case I had to show help text whenever the user clicks the header text so instead of adding ModalPopupExtender control to each and every HeaderTemplate what I did was add the ModalPopupExtender control somewhere in the aspx page and hooked it to a hidden control and on click of the header, used javascript to display the popup control. The reason why I took this approach is that if I put the ModalPoupExtender in each column’s header template, it will generate as many popup extenders as the number of columns. My popup control needs to display help text and these help texts were retrieved from a method in the code behind/webservice. So I used a javascript function and passed parameters necessary to retrieve the help text. Also people who have similar kind of requirement (where for example you have a column and you need to show some help text or some detailed information based on some parameters) you can also follow the same approach. The approach will reduce the amount of html being generated. With this approach I wanted to highlight the subtle feature of ModalPopupExtender control where one can hook up the control to a hidden control and use javascript to show the control. This method can be very useful for controls to which ModalPopupExtender cannot be attached. Now, let's see the code in action.
<asp:GridView ID="backIssueGrid" runat="server" 
AutoGenerateColumns="False" DataMember="issue" 
DataSourceID="backIssuesXML"> 
        <RowStyle BorderColor="Tan" 
BorderStyle="Solid" BorderWidth="1px" /> 
        <Columns> 
            <asp:TemplateField 
HeaderStyle-CssClass="headerText"> 
                <HeaderTemplate> 
                    <asp:HyperLink ID="title" 
runat="server" Text="Name" CssClass="gridText" 
NavigateUrl='javascript:showModalPopup("helpOne" 
);'></asp:HyperLink> 
                </HeaderTemplate> 
                <ItemTemplate> 
                    <asp:HyperLink ID="title" 
runat="server" Text='<%# XPath("@title") %>' 
CssClass="gridText" NavigateUrl='<%# 
XPath("url") %>'></asp:HyperLink>                        </ItemTemplate> 
                <HeaderStyle 
CssClass="headerText"></HeaderStyle> 
                <ItemStyle BorderColor="Tan" 
BorderStyle="Solid" BorderWidth="1px" />                        </asp:TemplateField> 
            <asp:TemplateField 
HeaderStyle-CssClass="headerText">                       <ItemTemplate> 
                    <asp:TextBox 
ID="quantityTxt" Width="30" runat="server" 
Text='<%#XPath("@noOfCopies") %>' 
CssClass="gridText"></asp:TextBox> 
                </ItemTemplate> 
                <ItemStyle BorderColor="Tan" 
HorizontalAlign="Center" BorderStyle="Solid" 
BorderWidth="1px" /> 
               <HeaderStyle 
CssClass="headerText"></HeaderStyle> 
                <HeaderTemplate> 
                    <asp:HyperLink ID="title" 
runat="server" Text="Address" CssClass="gridText"                         NavigateUrl='javascript:showModalPopup("helpTwo" 
);'></asp:HyperLink>                                             </HeaderTemplate> 
            </asp:TemplateField>            
            <asp:CommandField 
ShowSelectButton="True" ButtonType="Button" 
SelectText="Remove" ControlStyle-CssClass="buttonText" > 
            <ControlStyle 
CssClass="buttonText"></ControlStyle> 
            <ItemStyle BorderColor="Tan" 
BorderStyle="Solid" BorderWidth="1px" /> 
            </asp:CommandField> 
        </Columns>        
</asp:GridView> 
<asp:XmlDataSource ID="backIssuesXML" 
runat="server" 
DataFile="~/Data/BackIssue.xml"></asp:XmlDataSou 
rce> 
<asp:HyperLink ID="title" runat="server" 
Style="display:none;"> </asp:HyperLink> 
        <asp:Panel ID="webServicePanel" 
runat="server" Width="300px" Height="300" 
BackColor="Azure"> 
            <asp:Label ID="outputContentLbl" 
runat="server" Text="Label"></asp:Label> 
            <asp:Button ID="clsBtn" 
runat="server" Text="Button" /> 
        </asp:Panel> 
<cc1:ModalPopupExtender ID="ModalPopupExtender1" 
runat="server" DynamicServicePath="ModalPopup.aspx" 
TargetControlID="title" OkControlID="clsBtn" 
DynamicServiceMethod="HelloWorld" 
DynamicControlID="outputContentLbl"  
BackgroundCssClass="backgroundColor" PopupControlID="webServicePanel" DropShadow="true">        
</cc1:ModalPopupExtender>

Open in new window

The above code has ASP.NET hyper link controls in the header template that calls a javascript function using its NavigateUrl property and passes a string value to the javascript function based on which the help text is retrieved. Also as you can see we have a ModalPopupExtender control outside of GridView. A javascript function is used to show the popup control when you click the hyperlink controls inside the header template of the gridview. Also note the hyperlink control outside the GridView which has its style set to “None” so that the control becomes invisible. The javascript that is executed on clicking the hyperlink controls inside the GridView is pasted below.
//Javascript function to show the ModalPopupExtender control. 
function showModalPopup(helpId) 
{ 
    var modalPopup = $find('<%=ModalPopupExtender1.ClientID %>'); 
    if (modalPopup != null) 
    { 
        modalPopup._DynamicContextKey = helpId; 
        modalPopup.show(); 
    }    
}

Open in new window

In the above javascript we are setting the “_DynamicContextKey” with the help of the method argument. The argument is passed by the hyperlink controls in the header template of the GridView. DynamicContextKey is nothing but the string arguments to be passed to webservice/webpage method. So by varying the DynamicContextKey we can get different messages to be displayed in the ModalPopupExtender control.

The code behind method that is called by the ModalPopupExtender control is pasted below.
[System.Web.Services.WebMethod(), System.Web.Script.Services.ScriptMethodAttribute()] 
public static string HelloWorld(string contextKey) 
{ 
     return "<b>Hello World</b><br/>" + contextKey; 
}

Open in new window

Below are some of the important javascript properties and methods of ModalPopupExtender control.
_DynamicControlID: Using this property you can set/retrieve the ID for the dynamic control i.e. the control that will show the output of the method being pinged by the modal popup extender control.
_DynamicContextKey: Property to set/retrieve the string parameter for the function that will be called by the ModalPopupExtender control.
_DynamicServicePath: Property to set/retrieve the path for the webservice/webpage.
_DynamicServiceMethod: Property to set/retrieve the method that needs to be invoked or pinged to retrieve the output.
_PopupControlID: The property can be used to set/retrieve the ID of the control which will be shown as the popup. Normally it will be the ID of the ASP.NET panel control.
_PopupDragHandleControlID: The ID of the control clicking on which the popup control can be dragged.
_BackgroundCssClass: CSS class name for the background of the popup can be set/retrieved using this javascript property.
_DropShadow: Boolean value which can be set/retrieved to enable drop shadow. A value of “true” means drop shadow is enabled, false means it is disabled.
_Drag: Property to set/retrieve the drag facility. If you want to enable set it as true.
_OkControlID: This property can be used to set/retrieve the “Ok” button.
_CancelControlID: Property to set/retrieve the “Cancel” button id.
_OnOkScript: Property to set/retrieve the script that is to be fired when “Ok” button inside the popup is clicked.
_OnCancelScript: Property to set/retrieve the script that is to be fired when “Cancel” button inside the popup is clicked.
_xCoordinate: Property to set/retrieve the X coordinates of the popup control.
_yCoordinate: Property to set/retrieve the Y coordinates of the popup control.
_repositionMode: Property to set/retrieve the Reposition mode. Reposition mode has been discussed somewhere else in this document. The property accepts integer as its value. The various values and their corresponding reposition mode are as follows. 0 means “None”, 1 means “RepositionOnWindowResize”, 2 means “RepositionOnWindowScroll” and finally 3 means
“RepositionOnWindowResizeAndScroll”. Each of this mode is discussed above.
_id: One can set/retrieve the ID of the ModalPopupExtender control.       

My original article along with comments and discussion can be fond here.
4
Comment
Author:Sandeep P R
9 Comments
 
LVL 9

Author Comment

by:Sandeep P R
Hi,
Thanks for the suggestion. As with using inline server code (<%%>) it is implicitly understood that the javascript should be in an ASPX file. I have added a note that the inline server code will work only if the javascripts are in the same ASPX page.
Also I have rephrased the sentences. Please review the same and let me know if any changes needs to be done.
0
 
 

Administrative Comment

by:Eric AKA Netminder
sand1980,

Congratulations, and thank you! Your article has been published, and I have added the Community Pick and EE-Approved status for it as well.

ep
PE
0
 
LVL 96

Expert Comment

by:Bob Learned
This is a great article, and I wish I had found it earlier (alas!!)

I am trying to figure out how to change the drop shadow color from black, but I can't quite figure out the CSS, and I was wondering if you know anything about this?
0
VIDEO: THE CONCERTO CLOUD FOR HEALTHCARE

Modern healthcare requires a modern cloud. View this brief video to understand how the Concerto Cloud for Healthcare can help your organization.

 
LVL 9

Author Comment

by:Sandeep P R
Thanks. Sorry for the late reply.

Though I have not tried changing the drop shadow color, I can think of achieving it in one way. When a MPE is created it creates a div with an ID which has "_DropShadow" suffixed. The logic used to generate the ID is Panel control' ClientID +"_DropShadow". This div gives the background shadow effect to the MPE. The div has an inline CSS where the background color is set to black. Getting this control using javascript and manipulating the color can help.

var shadow= '<%=Panel1.ClientID %>' + '_DropShadow';
shadow.style.backgroundColor = "red";

I have not tried this, but I think this can be achieved. Please let me know.
0
 
LVL 96

Expert Comment

by:Bob Learned
There is some serious magic going on, because I don't see any shadow <div>, and even with Internet Explorer 8 Developer Tools I can't select that element, or see where it is rendered.  I have discovered another problem when I changed my page layout, where the offset for the shadow is calculated incorrectly, and it is drawn in the wrong place.  I haven't found any solution for that problem either.  The funny thing is that I didn't need the DropShadow, other than preventing a JavaScript error.  

I changed DropShadow to false this morning, and I am not getting that error anymore, so this has become a non-issue.  It is still a curiosity, though.
0
 
LVL 9

Author Comment

by:Sandeep P R
As you said it is difficult to find out the shadow div using the developer tools. I had to hover for long and repeatedly to find the shadow dive. This is what the auto generated shadow div looks like.

<div id="MainContent_Panel1_DropShadow" style="z-index: 1; position: absolute; background-color: black; width: 332px; height: 168px; visibility: inherit; top: 5px; left: 5px;"/>

Open in new window


I tried getting it using the $get method but it returned me null. Using the developer tool I was able to change the color successfully but using javascript I was not able to get the shadow div. If I get time will try to find out why this is happening.
0
 
LVL 96

Expert Comment

by:Bob Learned
This might be a good suggestion for the toolkit developers, so that you can just apply some CSS to the drop-shadow.  I can't find a good place to do that, though.
0
 
LVL 9

Author Comment

by:Sandeep P R
Yes I do agree. The simple thing they can do is expose a property in  MPE which will give the drop shadow javascript object. Once we have the object we can manipulate it according to our needs.
0
 

Expert Comment

by:nandiniraj
Hi,

Im very new to this ajax controls. I just tried to get the popup. I had pasted your code as it is . It is not giving any error but if run on browser and click on the button, the popup (panel) is not being showed ;-(

Dont know where i went wrong. Should i write anything in code behind to make it work?
Please help me.


Thanks in Advance
Nandini
0

Featured Post

Free Tool: Path Explorer

An intuitive utility to help find the CSS path to UI elements on a webpage. These paths are used frequently in a variety of front-end development and QA automation tasks.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

Join & Write a Comment

This video shows how to quickly and easily deploy an email signature for all users in Office 365 and prevent it from being added to replies and forwards. (the resulting signature is applied on the server level in Exchange Online) The email signat…
In response to a need for security and privacy, and to continue fostering an environment members can turn to for support, solutions, and education, Experts Exchange has created anonymous question capabilities. This new feature is available to our Pr…
Suggested Courses

Keep in touch with Experts Exchange

Tech news and trends delivered to your inbox every month