Flash AS3堆栈溢出

Question

我有一个我遵循的登录教程的代码。

package {

    /*
    always extend a class using movieclip instead of sprite when using flash.
    */

    import flash.display.MovieClip;
    import flash.events.*;
    import flash.net.*;
    import flash.text.*;


    /*
    create our class
    */



public class login extends MovieClip {

;


public function login ():void {

            var login_form:login = new login(); 
            addChild(login_form);
            var username:TextField = new TextField();
            addChild(username);
            var password:TextField = new TextField();
            addChild(password);
            var login_button:MovieClip = new MovieClip();
            addChild(login_button);

             /*
            buttonMode gives the submit button a rollover
            */

            login_button.buttonMode = true;

            /*
            what this says is that when our button is pressed, the checkLogin function will run
            */

            login_button.addEventListener(MouseEvent.MOUSE_DOWN, checkLogin);

            /*
            set the initial textfield values
            */

            username.text = "";
            password.text = "";

        }

public function checkLogin (e:MouseEvent):void {

            var username:TextField = new TextField();
            addChild(username);
            var password:TextField = new TextField();
            addChild(password);

    /*
    check fields before sending request to php
    */

    if (username.text == "" || password.text == "") {

        /*
        if username or password fields are empty set error messages
        */

        if (username.text == "") {

        username.text = "Enter your username";

        } 

        if (password.text == "") {

        password.text = "Enter your password";

        }

    } else {

        /*
        init function to process login
        */

        processLogin();

    }

}

public function processLogin ():void {

            var username:TextField = new TextField();
            addChild(username);
            var password:TextField = new TextField();
            addChild(password);

    /*
    variables that we send to the php file
    */

    var phpVars:URLVariables = new URLVariables();

    /*
    we create a URLRequest  variable. This gets the php file path.
    */

    var phpFileRequest:URLRequest = new URLRequest("php/controlpanel.php");

    /*
    this allows us to use the post function in php
    */

    phpFileRequest.method = URLRequestMethod.POST;

    /*
    attach the php variables to the URLRequest
    */

    phpFileRequest.data = phpVars;

    /*
    create a new loader to load and send our urlrequest
    */

    var phpLoader:URLLoader = new URLLoader();
    phpLoader.dataFormat = URLLoaderDataFormat.VARIABLES;   
    phpLoader.addEventListener(Event.COMPLETE, showResult);

    /*
    now lets create the variables to send to the php file
    */

    phpVars.systemCall = "checkLogin";
    phpVars.username = username.text;
    phpVars.password = password.text;

    /*
    this will start the communication between flash and php
    */

    phpLoader.load(phpFileRequest);

}

     public function showResult (event:Event):void {


                    var result_text:TextField = new TextField();
            addChild(result_text);


    /*

    this autosizes the text field

    ***** You will need to import flash's text classes. You can do this by adding: 

    import flash.text.*;

    ...to your list of import statements 

    */

    result_text.autoSize = TextFieldAutoSize.LEFT;

    /*
    this gets the output and displays it in the result text field
    */

    result_text.text = "" + event.target.data.systemResult;

}

}
}

我不确定在哪里放置我的按钮电影剪辑和文本字段的所有这些实例，但当我运行我的程序时，我得到了这个错误。

Error: Error #1023: Stack overflow occurred.
    at flash.display::DisplayObject()
    at flash.display::InteractiveObject()
    at flash.text::TextField()
    at flash.display::Sprite/constructChildren()
    at flash.display::Sprite()
    at flash.display::MovieClip()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()
    at login()

我试着寻找我能理解的答案，但一无所获。任何帮助都将不胜感激，谢谢。

Answer 1

您得到了Stack overflow错误，因为您在其构造函数中使用var login_form:login = new login();创建了一个实例化login类的无限循环，因此该类的每个实例都将创建另一个实例。

应仅在要插入类的时间/位置实例化该类，例如，在主时间轴或文档类中...，或仅通过将其直接拖放到舞台上。

但是在实例化login类之前，您应该正确地创建它。为此，您可以添加您的对象(Button、MovieClips、TextFields等)通过将它们拖放到MovieClip的舞台上，或通过使用以下命令的代码手动完成：

var username:TextField = new TextField();
addChild(username);

var password:TextField = new TextField();
addChild(password);

// LoginButton here is the AS linkage of a MovieClip/Button in the library  
var login_button:LoginButton = new LoginButton();
addChild(login_button);

这个操作通常只做一次，然后你可以像这样使用你的对象，例如：

 var user_name:String = username.text;

 if(password.text != ''){ /* ... */ }

 login_button.x = 30;

由于您是初学者，因此可以启动Learning ActionScript 3 here。

希望这能有所帮助。

Answer 2

您似乎是在创建login类的一个实例，并将其添加到其自身中，这导致了登录构造函数中的无限递归。

var login_form:login = new login();

您应该从另一个对象初始化登录类，然后将其添加到舞台上一次。