|By Michael Earls||
|May 20, 2005 11:00 AM EDT||
One of the most basic ways to navigate within an application is by use of a tab control. Tabs are easy to use and users are very familiar with them. There have been many implementations of tab controls for Web applications, but they had often required advanced client-side script that was only supported in a few browsers, or they required extensive and confusing server-side include files. ASP.NET 2.0 provides a few things that make this easier to do with no dependency on functional code. In this article I'll show you how you can use the new features of ASP.NET 2.0 to easily create a tab control for your Web application.
To get started, create a new Web site (use your favorite language) on your computer and call it TabDemo. ASP.NET 2.0 introduces a new set of data providers and controls based on the notion of a site map. The site map is the central data store for site navigation data. Let's start by defining a simple site map that we can use for our site. Add a new sitemap to the site (use the default name of Web.sitemap). Listing 1 shows a simple sitemap that will demonstrate the tabs nicely.
Now that we have our sitemap, we can continue with the actual user interface. To get the most benefit from the tab control, we'll use a master page to keep everything together. Add a new master page to your Web site and call it MasterPage.master (see Figure 1).
In order to make our tabs seem as though they're physically connected to our content, we'll need to create a master HTML table to contain the tabs. Delete the code between the <form> and </form> tags in the MasterPage.master file and replace it with the HTML in Listing 2.
That will give us the main table that will hold all of our content (including our tab control). Now we need to define the table that actually holds our tabs and the tab "panels." Let's take a look at Listing 3. It shows the HTML that we should put into the TD with the ID of ContentContainer.
Notice the use of the TD with the CSS class TabMenuSpacer. This cell forces the empty area behind the tabs to take up all of the excess space to the right of the menu. We need to add the SiteMapDataSource to our page so that the menu will be bound to our site map. This is easy to do. Simply add the following code just below the main table:
<asp:SiteMapDataSource ID="TabMenuSitemap" runat="server" ShowStartingNode="false" />
This adds a new SiteMapData-Source to the page. Since we used the default name of Web.sitemap for our site map, ASP.NET will automatically use it as the main site map for the site, so we don't have to do anything else. If you add another site map to the site, you'll need to define a new site map provider to the web.config file that points to your new site map, and then set the SiteMapProvider property of the SiteMapDataSource to your new site map provider. It's also important to point out that we set the ShowStartingNode property to false. We did this because we have a flat site map and we don't want to show the top-most parent node for our menu (since the site map is defined in XML, we had to have a root node, even though we'll never use it).
Let's go ahead and take a look at what we have so far. Delete the Default.aspx page that Visual Studio added to your site and replace it with a new Default.aspx page. This time, when you add the page, check the box labeled "Select master page." Then select MasterPage.master as the master page. Build and run the Web application. At this point, you'll see a very simple page that doesn't look like a whole lot (see Figure 2).
The reason our page looks so odd is because we haven't yet defined the Cascading Style Sheet for the page. We need to add the CSS that will actually render what we have as a Tab menu. Add a new style sheet to your project and name it Stylesheet.css. Then, add the following to the <head> of MasterPage.master:
<link href="StyleSheet.css" rel="stylesheet" type="text/css" />
This will link in the new style sheet. Let's take a look at the individual styles that make up our tab control. We'll start with the CSS class named TabMenuContainer. This style is applied to the entire tab menu. We just need to make sure that we have a top border so that our menu has a lid on it.
border-top: solid 1px black;
The next style that we're concerned with is the TabMenuItem. This is the style that is applied to all of our tabs in their unselected state.
border: solid 1px black;
padding: 3px 3px 3px 3px;
Notice that we've defined a border with a single pixel black line. We then set the left border to be nothing. This is actually an intentional move that prevents the tabs from looking bad against the border of the main container.
The secret to this whole method is in the next style. This is the style that is applied to the selected menu item:
border-right: solid 1px black;
padding: 5px 3px 5px 3px;
We set the bottom border to "none" and the background color to white. This will allow the tab to look as if it is attached to the content cell. We also set the top border to "none" to give the selected tab just a little more height than the other tabs.
Since we want our tab panels (the cell that contains the Content-PlaceHolder control) to be the same height from page to page, we should set them to be a specific height. Once again, we use CSS to define a style to do this. In the HTML for the master page we added a table cell to the right of the content container and set its CSS class to SiteContentSpacer. Let's set the style for that to be a specific height.
Not only did we set the height of the content to 200 pixels (a very small number just for demonstration purposes), but we also made the cell invisible. Listing 4 shows the entire style sheet that contains all of the styles used to make our tab control demo.
Once we've added the remaining styles to the style sheet, we can take a look at the final product. Figure 3 shows a screenshot of the resulting page with our tab control and all of the styles defined.
The tab control is a very useful user interface element that is common to many applications. With the introduction of master pages, SiteMapDataSource, and the menu control in ASP.NET 2.0, creating tabs in Web applications is easy. Best of all, once you have the master page set up for tabs, all you have to do to use them is to set the master page on your new Web forms and edit the page as you normally would. Also, since the solution relies on CSS, these tabs work in the latest Web browsers without any client-side coding.
|Aravind 05/06/08 09:09:19 AM EDT|
Great work, Thank you so much.
|Tony 04/02/08 04:22:56 PM EDT|
Thank you very much, I have been looking for a nice simple way to do this. Awesome article.
|Pranoti 03/07/08 03:18:06 PM EST|
Thank your very much, your tutorial helped me a lot
|Saurabh 01/28/08 10:49:37 PM EST|
It's really awesome. It really works. Thanks a lot. Really nice article.
|Aseem 12/20/07 06:07:54 AM EST|
Thanks for the easy to follow instructions in the article. How do we add a second layer to our tab navigation? IE when you click on one tab, the subtabs for that tab appear. Any help would be great also I need it urgently. Please help it out.
|Dave 11/26/07 02:05:38 PM EST|
Thanks for the easy to follow instructions in the article. How do we add a second layer to our tab navigation? IE when you click on one tab, the subtabs for that tab appear. Any help would be great.
|AK 11/16/07 04:51:45 PM EST|
Great! Worked really good for me first time, may have to make a dummies version for the less experienced...
|Rob 08/08/07 06:19:13 PM EDT|
Thanks for sharing that. Instructions were great and it all worked first time. I'm used to the tab control in Access and its good to have it in asp.net
|ChuckO 06/14/07 03:39:41 PM EDT|
The information in this article is not all correct. I followed his instructions and get the following error.
Content controls have to be top-level controls in a content page or a nested master page that references a master page.
|John Bowyer 12/30/05 03:35:37 AM EST|
I have implemented the tab control as documented to the best of my ability and it appears to have missing ingredients from the article.
When I select a tab, it does not highlight. In short it does not look like a tab at all. I also have dynamic mouse flyouts.
The article specifies as a class: TabMenu that is not inclided in Listing 1.
As more intelligent IoT applications shift into gear, they’re merging into the ever-increasing traffic flow of the Internet. It won’t be long before we experience bottlenecks, as IoT traffic peaks during rush hours. Organizations that are unprepared will find themselves by the side of the road unable to cross back into the fast lane. As billions of new devices begin to communicate and exchange data – will your infrastructure be scalable enough to handle this new interconnected world?
Oct. 13, 2015 10:15 PM EDT Reads: 171
SYS-CON Events announced today that Super Micro Computer, Inc., a global leader in high-performance, high-efficiency server, storage technology and green computing, will exhibit at the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. Supermicro (NASDAQ: SMCI), the leading innovator in high-performance, high-efficiency server technology is a premier provider of advanced server Building Block Solutions® for Data Center, Cloud Computing, Enterprise IT, Hadoop/Big Data, HPC and Embedded Systems worldwide. Supermi...
Oct. 13, 2015 09:00 PM EDT Reads: 266
Who are you? How do you introduce yourself? Do you use a name, or do you greet a friend by the last four digits of his social security number? Assuming you don’t, why are we content to associate our identity with 10 random digits assigned by our phone company? Identity is an issue that affects everyone, but as individuals we don’t spend a lot of time thinking about it. In his session at @ThingsExpo, Ben Klang, Founder & President of Mojo Lingo, will discuss the impact of technology on identity. Should we federate, or not? How should identity be secured? Who owns the identity? How is identity ...
Oct. 13, 2015 09:00 PM EDT Reads: 504
This week, the team assembled in NYC for @Cloud Expo 2015 and @ThingsExpo 2015. For the past four years, this has been a must-attend event for MetraTech. We were happy to once again join industry visionaries, colleagues, customers and even competitors to share and explore the ways in which the Internet of Things (IoT) will impact our industry. Over the course of the show, we discussed the types of challenges we will collectively need to solve to capitalize on the opportunity IoT presents.
Oct. 13, 2015 08:30 PM EDT Reads: 153
Today’s connected world is moving from devices towards things, what this means is that by using increasingly low cost sensors embedded in devices we can create many new use cases. These span across use cases in cities, vehicles, home, offices, factories, retail environments, worksites, health, logistics, and health. These use cases rely on ubiquitous connectivity and generate massive amounts of data at scale. These technologies enable new business opportunities, ways to optimize and automate, along with new ways to engage with users.
Oct. 13, 2015 07:00 PM EDT Reads: 290
WebRTC converts the entire network into a ubiquitous communications cloud thereby connecting anytime, anywhere through any point. In his session at WebRTC Summit,, Mark Castleman, EIR at Bell Labs and Head of Future X Labs, will discuss how the transformational nature of communications is achieved through the democratizing force of WebRTC. WebRTC is doing for voice what HTML did for web content.
Oct. 13, 2015 07:00 PM EDT Reads: 1,505
Through WebRTC, audio and video communications are being embedded more easily than ever into applications, helping carriers, enterprises and independent software vendors deliver greater functionality to their end users. With today’s business world increasingly focused on outcomes, users’ growing calls for ease of use, and businesses craving smarter, tighter integration, what’s the next step in delivering a richer, more immersive experience? That richer, more fully integrated experience comes about through a Communications Platform as a Service which allows for messaging, screen sharing, video...
Oct. 13, 2015 06:15 PM EDT Reads: 1,237
SYS-CON Events announced today that Dyn, the worldwide leader in Internet Performance, will exhibit at SYS-CON's 17th International Cloud Expo®, which will take place on November 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. Dyn is a cloud-based Internet Performance company. Dyn helps companies monitor, control, and optimize online infrastructure for an exceptional end-user experience. Through a world-class network and unrivaled, objective intelligence into Internet conditions, Dyn ensures traffic gets delivered faster, safer, and more reliably than ever.
Oct. 13, 2015 04:00 PM EDT Reads: 733
SYS-CON Events announced today that Sandy Carter, IBM General Manager Cloud Ecosystem and Developers, and a Social Business Evangelist, will keynote at the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA.
Oct. 13, 2015 03:15 PM EDT Reads: 263
The Internet of Things (IoT) is growing rapidly by extending current technologies, products and networks. By 2020, Cisco estimates there will be 50 billion connected devices. Gartner has forecast revenues of over $300 billion, just to IoT suppliers. Now is the time to figure out how you’ll make money – not just create innovative products. With hundreds of new products and companies jumping into the IoT fray every month, there’s no shortage of innovation. Despite this, McKinsey/VisionMobile data shows "less than 10 percent of IoT developers are making enough to support a reasonably sized team....
Oct. 13, 2015 01:00 PM EDT Reads: 350
The IoT market is on track to hit $7.1 trillion in 2020. The reality is that only a handful of companies are ready for this massive demand. There are a lot of barriers, paint points, traps, and hidden roadblocks. How can we deal with these issues and challenges? The paradigm has changed. Old-style ad-hoc trial-and-error ways will certainly lead you to the dead end. What is mandatory is an overarching and adaptive approach to effectively handle the rapid changes and exponential growth.
Oct. 13, 2015 01:00 PM EDT Reads: 343
With major technology companies and startups seriously embracing IoT strategies, now is the perfect time to attend @ThingsExpo in Silicon Valley. Learn what is going on, contribute to the discussions, and ensure that your enterprise is as "IoT-Ready" as it can be! Internet of @ThingsExpo, taking place Nov 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 17th Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The Internet of Things (IoT) is the most profound change in personal an...
Oct. 13, 2015 01:00 PM EDT Reads: 233
The IoT is upon us, but today’s databases, built on 30-year-old math, require multiple platforms to create a single solution. Data demands of the IoT require Big Data systems that can handle ingest, transactions and analytics concurrently adapting to varied situations as they occur, with speed at scale. In his session at @ThingsExpo, Chad Jones, chief strategy officer at Deep Information Sciences, will look differently at IoT data so enterprises can fully leverage their IoT potential. He’ll share tips on how to speed up business initiatives, harness Big Data and remain one step ahead by apply...
Oct. 13, 2015 12:00 PM EDT Reads: 752
There will be 20 billion IoT devices connected to the Internet soon. What if we could control these devices with our voice, mind, or gestures? What if we could teach these devices how to talk to each other? What if these devices could learn how to interact with us (and each other) to make our lives better? What if Jarvis was real? How can I gain these super powers? In his session at 17th Cloud Expo, Chris Matthieu, co-founder and CTO of Octoblu, will show you!
Oct. 13, 2015 12:00 PM EDT Reads: 312
Developing software for the Internet of Things (IoT) comes with its own set of challenges. Security, privacy, and unified standards are a few key issues. In addition, each IoT product is comprised of at least three separate application components: the software embedded in the device, the backend big-data service, and the mobile application for the end user's controls. Each component is developed by a different team, using different technologies and practices, and deployed to a different stack/target - this makes the integration of these separate pipelines and the coordination of software upd...
Oct. 13, 2015 12:00 PM EDT Reads: 417
As a company adopts a DevOps approach to software development, what are key things that both the Dev and Ops side of the business must keep in mind to ensure effective continuous delivery? In his session at DevOps Summit, Mark Hydar, Head of DevOps, Ericsson TV Platforms, will share best practices and provide helpful tips for Ops teams to adopt an open line of communication with the development side of the house to ensure success between the two sides.
Oct. 13, 2015 12:00 PM EDT Reads: 698
Today air travel is a minefield of delays, hassles and customer disappointment. Airlines struggle to revitalize the experience. GE and M2Mi will demonstrate practical examples of how IoT solutions are helping airlines bring back personalization, reduce trip time and improve reliability. In their session at @ThingsExpo, Shyam Varan Nath, Principal Architect with GE, and Dr. Sarah Cooper, M2Mi's VP Business Development and Engineering, will explore the IoT cloud-based platform technologies driving this change including privacy controls, data transparency and integration of real time context w...
Oct. 13, 2015 11:00 AM EDT Reads: 309
The Internet of Everything is re-shaping technology trends–moving away from “request/response” architecture to an “always-on” Streaming Web where data is in constant motion and secure, reliable communication is an absolute necessity. As more and more THINGS go online, the challenges that developers will need to address will only increase exponentially. In his session at @ThingsExpo, Todd Greene, Founder & CEO of PubNub, will explore the current state of IoT connectivity and review key trends and technology requirements that will drive the Internet of Things from hype to reality.
Oct. 13, 2015 11:00 AM EDT Reads: 326
"Matrix is an ambitious open standard and implementation that's set up to break down the fragmentation problems that exist in IP messaging and VoIP communication," explained John Woolf, Technical Evangelist at Matrix, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Oct. 13, 2015 07:00 AM EDT Reads: 6,014
Nowadays, a large number of sensors and devices are connected to the network. Leading-edge IoT technologies integrate various types of sensor data to create a new value for several business decision scenarios. The transparent cloud is a model of a new IoT emergence service platform. Many service providers store and access various types of sensor data in order to create and find out new business values by integrating such data.
Oct. 13, 2015 04:00 AM EDT Reads: 687