II.1.Each MXML component extends,or id derived from, an existing ActionScript class.
II.2. In an MXML component, each property that you want to be bindable needs its own [Bindable] tag.
With ActionScript class definitions, you can mark all the class's properties as bindable with a single instance of the [Bindable] metadata tag placed before the class declaration.
II.3.compc for libraries generation.
####page.256 23:22 2010-3-17
II.4.Navigator containers / View states
Navigator containers : Move from one view to another.
View states: change an existing view.
NOTE:
Q&A
Q:How to handling navigator container sizing?
A:3 ways:
1.Set the Set the navigator container's dimensions to specific pixel or percentage dimensions, and then set the nested container sizes to 100 percent height and width.Each of the nested view containers then resizes to fill the available space in the navigator container.
2.Set the nested containers to specific pixel dimensions, and set the navigator container's 'resizeToContent' property to true.
CAUTION:
Setting resizeToContent to true forces the navigator container to re-measure and
re-draw itself as the user navigates through the application. This can cause interesting
and unintended visual effects, particularly when the navigator container has a visible border or
background.
II.5.Backslash and Forwardslash character
Do not usint backslash character '\' as separator in the path to an application asset, you should always using forwardslash character '/' as separator.
II.6.New line
ActionScript: '\n'
MXML : " "
II.7.ActionScript basic access control
public
private
protected class and it subclass, note this is different from Java, which is allowed access in same package.
internal the default access specifier that allowed all other class which in the same package can access it.
BUT, if above default namespace is not suit for you, you can create your namespace.
III.1.To define an namespace, you have two choice: omit the URI or not, like:
namespace myzoo;
or
namespace myzoo = "http://www.myzoo.com";
once the namespace defined, in its using scope, it can't be redefined.
So, what the scope it control?
e.g,:
package org.mai {
namespace maizoo; //means internal.
}
package org.mai {
public namespace maizoo; //means it can be accessed by other class which it improved it.
}
III.2. Applying namespaces
e.g,:
namespace maizoo;
class MaiClass{
maizoo myFunction(){};
}
the namespace can be placed in front of variable, constant, function, but class.
III.3.Refrencing namespaces
Unlike the default namespaces, (public, private...etc;), which they are controled by context, the user defined namespace must be specified by user himself. Still, you can using the keyword 'use namespace' to simplicified it.(Like you did in C++!)
use namespace maizoo;
myFunction();
or
maizoo::myFunction();
II.8.The variable scope
ActionScript, unlike C++ or Java, doesn't have a 'block level scope', which means that if your declare a variable in a block, the variable is also available in anywhere of the function which the block belong to.
e.g,:
public function do:void(){
for(var i:int = 0; i < 20 ; i++){
var m:String = i + "xxx";
}
trance(m); // also avaiable here!
}
Because laking the block level scope variable scope, the compiler is ( almost is ) can understand how many variable is in some function, this is called 'hoisting', which can be thought as the compiler move all the variables declared to the top of an function. NOTE: the assignment will not be hositing, so the follow is easy understandable:
trace(num); // output NaN;
var num:Number = 20;
trace(num);// will outout 20.
II.9. Default value
| DataType | Value |
| Boolean | false |
| int | 0 |
| uint | 0 |
| Numbwer | NaN |
| * | undefined |
| Object | null |
| String | null |
| All Other Class | null |
II.10. is / instanceof /as
III.1.is / instanceof :: return Boolean.
is : can check an object is an instance of an class or an inherit from some class or it is implement of some interface.
instanceof: as well as 'is' but will be return false if using check an interface.
III.2. as
as : is return an string or null, to check an object is a member of a given data type.
e.g,:
var a:Sprite = new Sprite();
trace( a as Sprite); //[Object Sprite]
trace( a as IEDispatch); //[Object Sprite]
trace( a as Number); //null
II.11. Dynamic class and Sealed class
Dynamic class is a class which it's object can add method or variable at runtime. This is like javascript prototype but more strict.
But method added by this way is not have the ability to access the private variable.(NEED CHECKED!)
####page 83,proAS_Flex3 23:36 2010-3-23
II.12.Function Expressions and Statements
Thinking following example:
class MaiZoo{
var maiFunc = function(){};
function maiStateFunc(){};
}
var maiZoo:MaiZoo = new MaiZoo();
maiZoo.maiFunc(); //Error in 'Strick' mode;Ok in standard mode
maiZoo.maiStateFunc(); // Works fine in both mode.
If you wanna call an expression function in strick mode, the workaround way is:
maiZoo['maiFunc'](); //Guess what? like EL hah? And this is real a javascript way:)
Both satuation above code works fine.
Second way, you can declare whole class as 'dynamic',this way allow you call function express in strick mode, but this way will sacrifice the strick checking and if you attempt to access an undefined property for an instance,the compiler will not generate an error.(?)
III.1.Live sope
The different between function expression and function statement is that the function statement is exist throughtout the scope in which they are defined, INCLUDING IN THE STATEMENTS THAT APPEAR BEFORE THE FUNCTION STATEMENT!!!
But the function expression is not. So the following code will generate an error:
expressionFunc(); //Runtime Error
var expressionFunc:Function= function(){};
and if we using:
statementFunc(); //OK
function statementFunc():void{};
III.2. Delete property
dynamic class Obj{};
var myObj:Obj = new Obj();
myObj.expressionFunc = function(){};
delete myObj.expressionFunc;
myObj.expressionFunc(); //Error; cause the function is 'anonymous', it's just GONE!
//BUT..
function stateFunc():void{}
myObj.stateFunc = stateFunc;
delete stateFunc; //No effect.
stateFunc(); //Still working, lalala~
delete myObj.stateFunc;
myObj.steteFunc(); // Error!
stateFunc(); //Haha, Nondead!
II.13.Function ! Function! Function!
All thing is object, so all the function call is pass by refrence, BUT, for primer type, they works as if pass by value.
Have fixed argument(s) function has an imply object called 'arguments'
1. arguments is an array that contain all actual arguments the function be passed.
2. arguments.length
3. arguments.callee is an refrence to the function itself. so if you are using an anonymous function, you know how to do if you want do a recursion.
4. if you named your parameter 'arguments', it will overwrite the arguments, so you cry means nothing!
...(rest)
this is an way to define an function that not have the fixed but variable arguments.
e.g,:
function doX(... args):void{}
also, you can using (rest) as the way 'arguments' do in normal function, but they DONT HAVE an 'callee' attribute.
####page 101,proAS_Flex3 23:36 2010-3-23 22:19 2010-3-24