Welcome!

Adobe Flex Authors: Matthew Lobas, PR.com Newswire, Shelly Palmer, Kevin Benedict

Related Topics: Adobe Flex

Adobe Flex: Article

The NumericStepper Component

One of flash's hidden gems

Perhaps one of the easiest components to overlook in Flash MX 2004 is tucked away in the UI Components section of the Components Panel, and carries the uninteresting name NumericStepper. Perhaps you're developing experimental effects and require on-screen controls to alter dynamic feedback within those effects. Maybe you're building complex forms that allow users to quickly select numerical data. Either way, it's time to cast your eye over the NumericStepper component.

Let's look at an example. All the dynamics of the movie pictured below are controlled with instances of the NumericStepper.

NumericStepper is an extremely valuable component, but at its most basic, it's designed to step up or down through a series of numbers incrementally. There are several properties of the component that we can get and set. These extremely useful properties, which we'll explore in this article, are as follows:

  • minimum: the minimum value of the component
  • maximum: the maximum value of the component nextValue: the next incremental value of the component (read-only)
  • previousValue: the previous incremental value of the component (read-only)
  • stepSize: the incremental change value for the component
  • value: the currently selected value of the component
    Potential uses for the NumericStepper component include:
  • used as form elements to facilitate rapid numeric value selection
  • used as date selection elements (months, years etc)
  • used in experimental applications to control complex values
The main difference between the NumericStepper and ComboBox components, apart from the methods, properties and events, is to do with ease of use.

While you can accomplish similar effects using the ComboBox component, the NumericStepper component allows you to increment up or down a selection rapidly via the 'up' and 'down' arrows, or the up and down keys on the keyboard. Using the ComboBox, you need to click the ComboBox, wait for it to display the options, then select the desired value from a dropdown.

The NumericStepper solution is obviously much quicker than the ComboBox, and its capabilities allow NumericStepper to be implemented and used easily and effectively in some unique applications.

Numeric Stepper Basics
To get a feel for this component, let's add a single instance of NumericStepper to the stage. We'll then populate some dynamic text boxes with a couple of the NumericStepper component's properties.

The source FLA file for this example is called NumericStepperBasics.fla and can be found in the downloadable code archive accompanying the online version of this article at http://mxdj.sys-con.com.

Setting the Stage

  1. Start by creating a new Flash document. Accept the default width, height and frame rate settings.
  2. Rename the default layer Actions and add another layer beneath it called Components. Drag an instance of the NumericStepper component from the UI Components section of the Components panel into the first frame of the Components layer. Name the instance StepperMain.
  3. Select the NumericStepper component instance and add the following values within the Property Inspector: maximum:100, minimum:0; stepSize:5, value:10. Note: Here, we've added the component's property values via the Property Inspector, but we can also add these values programmatically via ActionScript if we wish (more on this later).
  4. Create two dynamic text boxes one above the other. Name the instances previousTextBox and nextTextBox.
    When we click the NumericStepper component, these text boxes will be populated with the next and previous values of the component. We'll add the ActionScript that achieves this in a moment.
  5. Add relevant labels to the component and text boxes if you wish, as shown in the above screenshot.
Let's move on. Now, we'll add the ActionScript that allows us to see the component in action...

Adding the ActionScript

  1. With the first frame of the Actions layer selected, add the following code within the Actions Panel:

    var palletteArray = new Array ();
    palleteArray = ["0x7FAAD4", "0xFFDF7F"];
    function setTheme() {
    _global.style.setStyle("themeColor", palleteArray[0]);
    _global.style.setStyle("backgroundColor", palleteArray[1]);
    _global.style.setStyle("fontSize", 11);
    _global.style.setStyle("fontWeight", "bold");
    _global.style.setStyle("color", palleteArray[0]);
    }
    setTheme(); // Called at startup

    var stepsListener = new Object();
    stepsListener.change = function() {
    populateTextBoxes();
    };
    stepperMain.addEventListener("change", stepsListener);

    function populateTextBoxes() {
    if ((stepperMain.value<stepperMain.maximum)
    && (stepperMain.value>stepperMain.minimum)) {
    nextTextBox.text = stepperMain.nextValue;
    previousTextBox.text = stepperMain.previousValue;
    }
    }
    The first thing that we are doing here is creating a new array called 'palletteArray', which we populate with a couple of color codes that we've selected for our interface: a nice pastel yellow (#7FAAD4) and a complementary blue (#FFDF7F).

    Note: Creating an array of colors makes it much easier to switch those colors if we need to: we simply change the values of different array members. This solution allows us to avoid having to search through the code, changing individual hexadecimal values as we find them.

    We then have a function called setTheme(), which is called at startup. It sets the theme for the NumericStepper component (or any other Flash MX 2004 component on the stage) using the palletteArray array we set up earlier.

    We then create a new listener object that listens for a change in the value of the NumericStepper component. When a change is detected, the populateTextBoxes() function is called. It pushes the nextValue and previousValue properties of the component to the relevant dynamic text boxes.

  2. Save the Flash document to a location of your choice and preview your work in Flash.
As you can see, clicking on the NumericStepper instance increments or decrements the values of the component, and pushes the next and previous values into the dynamic text areas.

More Stories By Steven Grosvenor

Steven Grosvenor is founder of Phireworx.com. His job title changes more often than his socks, but we're sure he does something important for a Managed Internet Security company in Manchester. A Ph.D. in Molecular Virology has served Steven well in the web industry, bearing no relevance at all, but this hasn't stopped him progressing so deep into code that nobody else understands. When not worked to death, his wife and young children ensure he can relax at home.

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


IoT & Smart Cities Stories
The challenges of aggregating data from consumer-oriented devices, such as wearable technologies and smart thermostats, are fairly well-understood. However, there are a new set of challenges for IoT devices that generate megabytes or gigabytes of data per second. Certainly, the infrastructure will have to change, as those volumes of data will likely overwhelm the available bandwidth for aggregating the data into a central repository. Ochandarena discusses a whole new way to think about your next...
CloudEXPO | DevOpsSUMMIT | DXWorldEXPO are the world's most influential, independent events where Cloud Computing was coined and where technology buyers and vendors meet to experience and discuss the big picture of Digital Transformation and all of the strategies, tactics, and tools they need to realize their goals. Sponsors of DXWorldEXPO | CloudEXPO benefit from unmatched branding, profile building and lead generation opportunities.
DXWorldEXPO LLC announced today that Big Data Federation to Exhibit at the 22nd International CloudEXPO, colocated with DevOpsSUMMIT and DXWorldEXPO, November 12-13, 2018 in New York City. Big Data Federation, Inc. develops and applies artificial intelligence to predict financial and economic events that matter. The company uncovers patterns and precise drivers of performance and outcomes with the aid of machine-learning algorithms, big data, and fundamental analysis. Their products are deployed...
All in Mobile is a place where we continually maximize their impact by fostering understanding, empathy, insights, creativity and joy. They believe that a truly useful and desirable mobile app doesn't need the brightest idea or the most advanced technology. A great product begins with understanding people. It's easy to think that customers will love your app, but can you justify it? They make sure your final app is something that users truly want and need. The only way to do this is by ...
Digital Transformation and Disruption, Amazon Style - What You Can Learn. Chris Kocher is a co-founder of Grey Heron, a management and strategic marketing consulting firm. He has 25+ years in both strategic and hands-on operating experience helping executives and investors build revenues and shareholder value. He has consulted with over 130 companies on innovating with new business models, product strategies and monetization. Chris has held management positions at HP and Symantec in addition to ...
Dynatrace is an application performance management software company with products for the information technology departments and digital business owners of medium and large businesses. Building the Future of Monitoring with Artificial Intelligence. Today we can collect lots and lots of performance data. We build beautiful dashboards and even have fancy query languages to access and transform the data. Still performance data is a secret language only a couple of people understand. The more busine...
Cell networks have the advantage of long-range communications, reaching an estimated 90% of the world. But cell networks such as 2G, 3G and LTE consume lots of power and were designed for connecting people. They are not optimized for low- or battery-powered devices or for IoT applications with infrequently transmitted data. Cell IoT modules that support narrow-band IoT and 4G cell networks will enable cell connectivity, device management, and app enablement for low-power wide-area network IoT. B...
The hierarchical architecture that distributes "compute" within the network specially at the edge can enable new services by harnessing emerging technologies. But Edge-Compute comes at increased cost that needs to be managed and potentially augmented by creative architecture solutions as there will always a catching-up with the capacity demands. Processing power in smartphones has enhanced YoY and there is increasingly spare compute capacity that can be potentially pooled. Uber has successfully ...
SYS-CON Events announced today that CrowdReviews.com has been named “Media Sponsor” of SYS-CON's 22nd International Cloud Expo, which will take place on June 5–7, 2018, at the Javits Center in New York City, NY. CrowdReviews.com is a transparent online platform for determining which products and services are the best based on the opinion of the crowd. The crowd consists of Internet users that have experienced products and services first-hand and have an interest in letting other potential buye...
When talking IoT we often focus on the devices, the sensors, the hardware itself. The new smart appliances, the new smart or self-driving cars (which are amalgamations of many ‘things'). When we are looking at the world of IoT, we should take a step back, look at the big picture. What value are these devices providing. IoT is not about the devices, its about the data consumed and generated. The devices are tools, mechanisms, conduits. This paper discusses the considerations when dealing with the...