AS3 CookBook学习整理(一)
1. 我要改变swf的尺寸和颜色
在flex builder 3里，默认会生成一个全屏、背景色为#869CA7、帧数为24/秒的swf文件，要修改这些参数，只需要在类文件中定义 [SWF(width="800", height="600", backgroundColor="#ffffff", frameRate="31")]
package hxw
{
import flash.display.Sprite;
[SWF(width="800", height="600", backgroundColor="#ff0000", frameRate="31")]
public class ExampleApplication extends Sprite
{
public function ExampleApplication()
{
}
}
}
2. 我要重复执行某段代码
在enterFrame事件中添加监听器和关联处理方法
package hxw
{
import flash.display.Sprite;
import flash.events.Event;
public class Sample1009 extends Sprite
{
public function Sample1009()
{
graphics.lineStyle(3,0xFF0000,1);
addEventListener(Event.ENTER_FRAME,onEnterFrame);
}
private function onEnterFrame(event:Event):void
{
graphics.lineTo(Math.random()*400,Math.random()*400);
}
}
}
3. 如何响应鼠标事件
为MouseEvent系列事件添加监听器和关联处理方法
package hxw
{
import flash.display.Sprite;
import flash.events.MouseEvent;
[SWF(width="800", height="600", backgroundColor="#869CA7", frameRate="31")]
public class Sample1010 extends Sprite
{
private var _sprite:Sprite;
public function Sample1010()
{
_sprite = new Sprite();
_sprite.graphics.beginFill(0x27496E);
_sprite.graphics.drawRect(5,5,400,400);
_sprite.graphics.endFill();
_sprite.addEventListener(MouseEvent.MOUSE_DOWN,OnMouseDown);
_sprite.addEventListener(MouseEvent.MOUSE_UP,OnMouseUp);
this.addChild(_sprite);
}
private function OnMouseDown(event:MouseEvent):void
{
_sprite.graphics.lineStyle(1,0xFFFF00,1);
_sprite.graphics.moveTo(mouseX,mouseY);
_sprite.addEventListener(MouseEvent.MOUSE_MOVE,OnMouseMove);
}
private function OnMouseUp(event:MouseEvent):void
{
_sprite.removeEventListener(MouseEvent.MOUSE_MOVE,OnMouseMove);
}
private function OnMouseMove(event:MouseEvent):void
{
_sprite.graphics.lineTo(mouseX,mouseY);
}
}
}
4. 如何响应键盘事件
为KeyboardEvent事件添加监听器和关联处理方法
package {
import flash.display.Sprite;
import flash.events.KeyboardEvent;
public class Sample1030 extends Sprite
{
public function Sample1030()
{
//stage.focus = this;
stage.addEventListener(KeyboardEvent.KEY_DOWN,OnKeyDown);
}
private function OnKeyDown(event:KeyboardEvent):void
{
trace(event.charCode);
}
}
}
5. 如何实现定时器(Timer)
初始化一个Timer类，使用addEventListener来设置一个函数处理这个事件，然后使用timer的start( )方法启动或stop( )停止它。
package {
import flash.display.Sprite;
import flash.events.TimerEvent;
import flash.utils.Timer;
public class Sample1101 extends Sprite
{
private var _rect:Sprite;
private var _circle:Sprite;
public function Sample1101()
{
_rect = new Sprite();
_circle = new Sprite();
_rect.graphics.beginFill(0xFFFF00);
_rect.graphics.drawRect(0,0,100,100);
_rect.graphics.endFill();
_rect.x = 50;
_rect.y = 100;
this.addChild(_rect);
_circle.graphics.beginFill(0x80C56E);
_circle.graphics.drawCircle(0,0,50);
_circle.graphics.endFill();
_circle.x = 100;
_circle.y = 200;
this.addChild(_circle);
var _timer:Timer = new Timer(50);
_timer.addEventListener(TimerEvent.TIMER,OnTimerTick);
_timer.addEventListener(TimerEvent.TIMER,OnTimerTick2);
_timer.start();
}
private function OnTimerTick(event:TimerEvent):void
{
_rect.x += 20;
}
private function OnTimerTick2(event:TimerEvent):void
{
_circle.y += 30;
}
}
}
6. 获得客户端的操作系统版本
ActionScript 3.0中，flash.system.Capabilities.os 属性返回操作系统名称和版本字符串。值可能包括Windows XP, Windows 2000, Windows NT, Windows 98/Me, Windows 95, 和Windows CE. 在苹果机上，字符串包括版本号，比如Mac OS 9.2.1 或Mac OS X 10.4.4
package {
import flash.display.Sprite;
import flash.system.Capabilities;
public class Sample1101 extends Sprite
{
public function Sample1101()
{
var os:String = flash.system.Capabilities.os.substr(0,3);
if (os == "Win") {
// Windows-specific code goes here
}
else if (os == "Mac") {
// Mac-specific code goes here
}
else {
// Must be Unix or Linux
}
}
}
}
7. 获得客户端的播放器类型
使用flash.system.Capabilities.playerType属性。它可能是PlugIn, ActiveX,StandAlone和External。
播放器的类型有：
浏览器插件形式存在于Mozilla 或Firefox
ActiveX 控件形式存在于Internet Explorer
独立播放器
外部播放器，它与Flash IDE进行交互
package {
import flash.display.Sprite;
import flash.system.Capabilities;
public class Sample1101 extends Sprite
{
public function Sample1101()
{
if(flash.system.Capabilities.playerType == "Plugin")
{
// do actions for Mozilla, etc. browsers
}
else if(flash.system.Capabilities.playerType == "ActiveX")
{
// do actions for IE
}
else
{
// do actions for no browser
}
}
}
}
8. 获得客户端的语言与输入法
使用flash.system.Capabilities.language 属性和flash.system.IME 类
package {
import flash.display.Sprite;
import flash.system.IME;
public class Sample1101 extends Sprite
{
public function Sample1101()
{
// 从capabilities 对象上得到语言值
var lang:String = flash.system.Capabilities.language.substr(0, 2);
// 创建支持语言数组>
var supportedLanguages:Array = ["en", "es", "fr"];
// 设置默认语言.
var useLang:String = "en";
//循环匹配，如果找到，设置useLang
for (var i:int = 0; i < supportedLanguages.length; i++)
{
if (supportedLanguages[i] == lang)
{
useLang = lang;
break;
}
}
// 载入对应Flash
var movieURL:String = "myMovie_" + useLang + ".swf";
}
}
}
9. 获得客户端的分辨率
screenResolutionX 和screenResolutionY 属性返回桌面的显示分辨率：
trace(flash.system.Capabilities.screenResolutionX); // 1024
trace(flash.system.Capabilities.screenResolutionY); // 768
package {
import flash.display.Sprite;
import flash.external.ExternalInterface;
import flash.system.Capabilities;
public class Sample1101 extends Sprite
{
public function Sample1101()
{
var screenX:int = flash.system.Capabilities.screenResolutionX;
var screenY:int = flash.system.Capabilities.screenResolutionY;
var winW:int = 200;
var winH:int = 200;
var winX:int = (screenX / 2) - (winW / 2);
var winY:int = (screenY / 2) - (winH / 2);
var jsCode:String = "javascript:void(newWin=window.open('http://www.person13.com/'," +
"'newWindow', 'width=" + winW +
", height=" + winH + "," +
"left=" + winX + ",top=" + winY + "'));";
ExternalInterface.call(jsCode);
}
}
}
10. 缩放影片
设置stage.scaleMode，scaleMode属性值并不影响右键菜单里功能，不过你可以禁用菜单里的缩放功能。
stage.scaleMode的值来自flash.display.StageScaleMode类的枚举，有EXACT_FIT, NO_BORDER,NO_SCALE, 和SHOW_ALL
假设原影片如下：
1. SHOW_ALL
这种模式会成比例缩小与放大。如果播放器与影片的比例不一致，则会出现空白边框。以SHOW_ALL模式缩小后的效果如下：
2. EXACT_FIT
这种模式会不成比例缩小与放大。以EXACT_FIT模式缩小后的效果如下：
3. NO_BORDER
这种模式会成比例缩小与放大。如果播放器和影片比例不一致，则会裁剪影片。以NO_BORDER模式缩小后的效果如下：
4. NO_SCALE
这种模式不进行缩放，保持原有比例。使用该模式不要忘了设置对齐方式。