ActionScript 3.0 Cookbook: Chapter 3, Runtime Environment
Pages: 1, 2, 3, 4, 5

It is also often important to know how a user will be entering text on her system. Languages, such as Chinese, Japanese, and Korean, can have thousands of possible characters. To enter these characters via the keyboard, a special program called an Input Method Editor (IME) is required. This is usually part of the operating system of the particular language.

To detect if the user's system has an IME, check the value of flash.system.Capabilities.hasIME, which will return true or false. Then use the flash.system.IME class to get more information about and interact with the IME. The flash.system.IME.enabled property tells you whether the user is using the IME or entering text straight from the keyboard. This property is actually writable, so you can use it to turn on the IME. On some platforms and OS versions, you can send a string to the IME to be converted into the correct characters, and accept the output of the IME back into a selected text field. Since this does not work on all systems, it is best to check the OS first (see Recipe 3.2).

See Also

Recipe 3.2

Section 3.5: Detecting Display Settings

Problem

You want to know the display settings for the device on which the movie is being played.

Solution

Use the screenResolutionX and screenResolutionY properties of the system.capabilities object.

Discussion

You should use the flash.system.Capabilities object to determine the display settings of the device that is playing the movie. The screenResolutionX and screenResolutionY properties return the display resolution in pixels.

// Example output:
// 1024
// 768
trace(flash.system.Capabilities.screenResolutionX);
trace(flash.system.Capabilities.screenResolutionY);

You can use these values to determine how to display a movie, or even which movie to load. These decisions are increasingly important as more handheld devices support the Flash Player. For example, the dimensions of a cellphone screen and a typical desktop computer display are different, so you should load different content based on the playback device.

var resX:int = flash.system.Capabilities.screenResolutionX;
var resY:int = flash.system.Capabilities.screenResolutionY;

// If the resolution is 240 x 320 or less, then load the PocketPC
// movie version. Otherwise, assume the device is a desktop computer 
// and load the regular content.
if ( (resX <= 240) && (resY <= 320) ) {
  var url:String = "main_pocketPC.swf";
}
else {
  var url:String = "main_desktop.swf";
}
loader.load(new URLRequest(url));

You can also use the screen resolution values to center a pop-up browser window:

var resX:int = flash.system.Capabilities.screenResolutionX;
var resY:int = flash.system.Capabilities.screenResolutionY;

// Set variables for the width and height of the new browser window.
var winW:int = 200;
var winH:int = 200;

// Determine the X and Y values to center the window.
var winX:int = (resX / 2) - (winW / 2);
var winY:int = (resY / 2) - (winH / 2);

// Create the code that, when passed to URLLoader.load( )
// opens the new browser window.
var jsCode:String = "javascript:void(
         newWin=window.open('http://www.person13.com/'," + 
         "'newWindow', 'width=" + winW +
         ", height=" +  winH + "," + 
         "left=" + winX + ",top=" + winY + "'));";

// Call the JavaScript function using a URLLoader object
urlLoader.load(new URLRequest(jsCode));

This excerpt is from ActionScript 3.0 Cookbook. Well before Ajax and Windows Presentation Foundation, Macromedia Flash provided the first method for building "rich" web pages. Now, Adobe is making Flash a full-fledged development environment, and learning ActionScript 3.0 is key. That's a challenge for even the most experienced Flash developer. This Cookbook offers more than 300 solutions to solve a wide range of coding dilemmas, so you can learn to work with the new version right away.

Additionally, it is worth considering using the screen resolution values to determine whether or not to scale a movie. For example, when users have their resolution set to a high value, such as 1600/code>.

The Flash Player defaults to a scale mode of showAll. In this mode, the Flash movie scales to fit the player's size while maintaining the movie's original aspect ratio. The result is that the movie can potentially have borders on the sides if the Player's aspect ratio does not match the movie's aspect ratio. You can set a movie to showAll mode from your main application class as follows (don't forget to import the flash.display.StageScaleMode class):

stage.scaleMode = StageScaleMode.SHOW_ALL;

Note that stage is not a global object, but a property of any display object, so this statement only works in a sprite or other class that extends the DisplayObject class.

The noBorder mode scales a movie to fit the Player while maintaining the original aspect ratio; however, it forces the Player to display no borders around the Stage. If the aspect ratio of the Player does not match that of the movie, some of the movie will be cut off on the sides. You can set a movie to noBorder mode as follows:

stage.scaleMode = StageScaleMode.NO_BORDER;

The exactFit mode scales a movie to fit the Player, and it alters the movie's aspect ratio, if necessary, to match that of the Player. The result is that the movie always fills the Player exactly, but the elements of the movie may be distorted. For example:

stage.scaleMode = StageScaleMode.EXACT_FIT;

In noScale mode, the movie is not scaled, and it maintains its original size and aspect ratio regardless of the Stage's size. When you use the noScale mode, don't forget to set the movie's alignment (see Recipe 3.7, which includes example code that demonstrates the available alignment options). For example:

stage.scaleMode = StageScaleMode.NO_SCALE;

The scaleMode property's value does not prevent the user from being able to scale the movie using the right-click/Control-click menu. However, you can disable those options in the menu, as shown in Recipe 3.8.

See Also

Recipes 3.7 and 3.8

Section 3.7: Changing the Alignment

Problem

You want to change the alignment of the movie within the Player.

Solution

Use the stage.align property.

Discussion

Flash movies appear in the center of the Player by default. You can control the alignment of a movie within the Player by setting the stage.align property of any class that extends DisplayObject. The various alignment modes are implemented as strings, such as "T" for "top," "L" for "left," etc. However, to avoid errors in typing, these have also been made properties of the flash.display.StageAlign class, listed in Table 3-1.