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ptg 380 Chapter 15 There are several key ways to control data in ActionScript 3.0. They include Arrays, Shared Objects and XML. An Array is the first method you are likely to use in your ActionScript code. The role of an Array is to create a list of data types in your code. For example, you may want to list the colors red, green, blue and orange. To do this you need to define a new variable with the data type of Array: var colorArray:Array = new Array("red", "green", "blue", "orange"); You can see in this script that a set of four items have been inserted into the Array. You can access the data in the Array with the fol- lowing trace statement: trace (colorArray); The “push” property will allow you to add a new item into your array: colorArray.push("purple"); To re move the l ast it em of an A rray yo u can use the Pop property. colorArray.pop(); What you will find is that Arrays are great for manage simple lists. Additional properties allow you to remove specific values, to count the number of values you have and to sort your lists. For more complex data you will want to leverage the Local Data Storage or XML. When you are counting the number of values in an Array you have to remember that Arrays always start with 0. For instance, if you have five items in an array and tell the array to pull item 1, it will pull the second item. This is because the first item has the registered value of 0. If you are developing an AIR solution you can take advantage of the SQL database built right into AIR. The SQL database comes with support for the creation of tables, stored pro- cedures and SQL statements. Using Flash Cookies The Flash Player can also store data locally in very much the same way that a cookie can be stored in a Web browser. Flash does not call this cookies but Shared Objects. An example of Share Object ActionScript 3.0 is: var mySO:SharedObject = SharedObject.getLocal("myFlashCookie"); mySO.data.now = new Date().time; trace(mySO.data.now); The Share Object is declared and given a name where it will be stored on the local computer. You can now effectively target data to this space that can be accessed if this com- puter comes back to this page at a later date. Controlling Data From the Library of Wow! eBook ptg Chapter 15 Working with ActionScript 3.0 381 Manipulating XML with E4X Flash has supported XML in one fashion or another since Flash 5. Have you worked with XML in ActionScript 2.0? It’s not pretty. To our relief, ActionScript 3.0 now supports the ECMA XML standard called E4X. You can now more easily step through your XML docu- ments. You can also change the value of items into an XML document. What this means is that you can load an XML document and then modify the content. For instance, you can change Yellow to Blue. Import an XML Document as a Data Type Before you can import an XML document, you need to create one. You can use the following code and save it as an XML document with the name colors.xml . <?xml version="1.0" encoding="UTF-8"?> <pallette> <color>Orange</color> <color>Red</color> <color>Yellow</color> </pallette> Click the File menu, click New , click ActionScript 3.0 , and then click OK . Click the File menu, and then click Save to save the FLA file to the same folder as the XML document. The first step is to create a new object to manage the XML: var myXml:XML; The next step is to create a new URLLoader file that will load the XML file: var xmlLoader = new URLLoader(); 5 4 3 2 1 xmlLoader.addEventListener (Event.COMPLETE,onXMLLoaded); xmlLoader.load (new URLRequest("colors.xml")); At this point you have loaded the XML successfully into Flash. You can test this by adding the following function to trace the contents of the XML document into your OutPut window. function onXMLLoaded(e:Event):void{ myXml = new XML(e.target.data); trace(myXml); } You can now easily pull out a specific value. For instance, add the following to the onXMLLoaded function to extract the third value in the XML file: trace(myXml color[2]); The double dots after the variable myXML allows you to step to the second value of your XML document. All of this is so much easier to accomplish with E4X than with ActionScript 2.0. 7 6 From the Library of Wow! eBook ptg 382 Chapter 15 Patterns are everywhere as you develop your code. This is clearly seen with the use of Regular Expressions, a method for describing the pattern of data you are looking to use. Using Regular Expressions you can now eas- ily format form fields to correctly capture date, ZIP or Credit Card numbers. To va lid ate da ta me ets a si mpl e patte rn yo u need to create a string variable: var myColor = "Orange"; Now create a new regular expression that is looking for a simple pattern. In this instance, the pattern is that the myColor string value must start with an “O”. var colorRegExp:RegExp = /O/; You can write a trace script to test your movie: trace( colorRegExp.test( myColor ) ); The value in the Output panel is True. Let’s extend what you can do with Regular Expressions by adding a pattern that looks for an email address. Start by adding a new email string with a valid email address: var email:String = "mdavid@matthewdavid.ws"; Next, create a new Regular Expression that is looking for a pattern structure in your email: var emailRegExp:RegExp = /^([a-zA-Z0-9_-]+)@([a- zA-Z0-9 ]+)\.([a-zA-Z]{2,4})$/i; The pattern is looking for a combination of alpha-numerical-special character formats separated by an “@” sign and suffix “.” Add the following trace statement to see whether or not the pattern works: trace( "Is this email valid? " + emailRegExp.test( email ) ) Tes t the movi e to vie w the fo llo win g res pon se in the Output panel: Is this email valid? True Change the email address to just “Matthew David” a pattern that does not match the Regular Expression. When you test the movie you will see that the Regular Expression returns a false response. You can also get great information on how to structure regular expressions at: http://www.regular-expressions.info . Using Regular Expressions From the Library of Wow! eBook ptg Chapter 15 Working with ActionScript 3.0 383 Controlling Text In many ways you do not need to work on the Stage at all when using ActionScript 3.0. All visual objects can be programmatically cre- ated. The easiest way to see this is in using the Text object to create dynamic text fields on the Stage. Create a Dynamic Text Field Click the File menu, click New , click ActionScript 3.0 , and then click OK . Open the Properties panel. Click the Edit Class Definition button (small pencil icon) in the Properties inspector, enter a new class with the name text , and then click OK . A new ActionScript file named text.as opens. Add the libraries to be imported into your file: import flash.display.Sprite; import flash.text.TextField; import flash.text.TextFieldAutoSize; import flash.text.TextFormat; Insert a private variable that will be used to define the dynamic text: private var myTextField:TextField; The following creates a basic string you can insert into your texftfield: private var someText:String = "Hello world."; A private function is used to define the physical position of the textfield on the screen. Declare the text field as a new object, and then use the X and Y properties to place the text on the screen: 7 6 5 4 3 2 1 private function configuretext():void { myTextField = new TextField(); myTextField.y = 200; myTextField.x = 100; A textFormat object is used to format the visual properties of the text. For instance, the following textFormat object sets the font to “_sans”, the color black and font size 15: var format:TextFormat = new TextFormat(); format.font = "_sans"; format.color = 0x000000; format.size = 15; myTextField.defaultTextFormat = format; addChild(myTextField); The final two public functions tie the text string to the new formatted text field: public function text() { configuretext(); setValueOfTextField(someText); } public function setValueOfTextField (str:String):void { myTextField.text = str; } Click the Control menu, point to Test Movie , and then click Test to display a text string added to your screen. Creating a dynamic text field on the Stage with ActionScript allows you more control over the text on the Stage than using tradi- tional methods. 10 9 8 From the Library of Wow! eBook ptg 384 Chapter 15 As with the text object, you can create images dynamically in ActionScript 3.0. There are sev- eral different types of image you can create that include traditional Movie Clips and Graphics. You can now also create a new type of image called a Sprite. Essentially, a Sprite is the same as a Movie Clip with the excep- tion that it does not contain timeline function- ality. Sprite’s can be created by invoking the new Sprite Object Class and then adding properties to the object. Add a Square Shaped Sprite to the Stage Add the following ActionScript to create a new Sprite with the name myFirstSprite . var myFirstSprite:Sprite = new Sprite(); addChild(myFirstSprite); 1 The following ActionScript formats the size, fill/outline color, and position of the Sprite: myFirstSprite.graphics.lineStyle(3,0xFF6600); myFirstSprite.graphics.beginFill(0xFF0000); myFirstSprite.graphics.drawRect(0,0,100,100); myFirstSprite.graphics.endFill(); Click the Control menu, point to Test Movie , and then click Test to view the rectangle on the screen. The following ActionScript applies a fade in transition effect to your new Sprite. myFirstSprite.addEventListener (Event.ENTER_FRAME, fadeInSprite); myFirstSprite.alpha = 0; function fadeInSprite(event:Event) { myFirstSprite.alpha += 0.01; if(myFirstSprite.alpha >= 1) { myFirstSprite.removeEventListener (Event.ENTER_FRAME, fadeInSprite); } } You can do a lot with ActionScript constructed images. Working with the all the different objects available to you in ActionScript 3.0 you have almost no limits to what you can create using Flash. 4 3 2 Drawing with the Shape Class From the Library of Wow! eBook . imported into your file: import flash. display.Sprite; import flash. text.TextField; import flash. text.TextFieldAutoSize; import flash. text.TextFormat; Insert. statements. Using Flash Cookies The Flash Player can also store data locally in very much the same way that a cookie can be stored in a Web browser. Flash does

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