+Show TOC
×Hide TOC

Load

Kind of class:	class
Inherits from:	EventDispatcher < CoreObject
Implements:	LoadInterface
Known subclasses:	RetryableLoad
Version:	05/06/07
Author:	Aaron Clinger
Classpath:	org.casalib.load.base.Load
File last modified:	Monday, 01 December 2008, 13:34:40

► View source

▼ Hide source

/*
    CASA Lib for ActionScript 2.0
    Copyright (c) 2008, Aaron Clinger & Contributors of CASA Lib
    All rights reserved.
    
    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are met:
    
    - Redistributions of source code must retain the above copyright notice,
      this list of conditions and the following disclaimer.
    
    - Redistributions in binary form must reproduce the above copyright notice,
      this list of conditions and the following disclaimer in the documentation
      and/or other materials provided with the distribution.
    
    - Neither the name of the CASA Lib nor the names of its contributors
      may be used to endorse or promote products derived from this software
      without specific prior written permission.
    
    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
    LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
    CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
    SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
    INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    POSSIBILITY OF SUCH DAMAGE.
*/

import org.casalib.event.EventDispatcher;
import org.casalib.load.base.LoadInterface;
import org.casalib.time.FrameDelay;

/**
    Base load class. Class needs to be extended further to function properly.
    
    @author Aaron Clinger
    @version 05/06/07
    @since Flash Player 7
*/

class org.casalib.load.base.Load extends EventDispatcher implements LoadInterface {
    public static var EVENT_LOAD_START:String    = 'onLoadStart';
    public static var EVENT_LOAD_ERROR:String    = 'onLoadError';
    public static var EVENT_LOAD_COMPLETE:String = 'onLoadComplete';
    public static var EVENT_LOAD_INIT:String     = 'onLoadInit';
    private var $filePath:String;
    private var $target:Object;
    private var $hasLoaded:Boolean;
    private var $isLoading:Boolean;
    private var $frameDelay:FrameDelay;
    
    
    /**
        @param target: A path to a container where the file specified by <code>filePath</code> should be loaded into.
        @param filePath: The absolute or relative URL of the file to be loaded.
    */
    private function Load(target:Object, filePath:String) {
        super();
        
        this.$target    = target;
        this.$filePath  = filePath;
        this.$hasLoaded = this.$isLoading = false;
        
        this.$setClassDescription('org.casalib.load.base.Load');
    }
    
    /**
        Begins the loading process and broadcasts events to observers.
        
        @usageNote Use {@link EventDispatcher#addEventObserver} to listen for broadcasted events.
        @sends onLoadStart = function(sender:Load) {}
    */
    public function start():Void {
        if (this.isLoading() || this.hasLoaded())
            return;
        
        if (this.$filePath == undefined || this.$target == undefined) {
            this.dispatchEvent(Load.EVENT_LOAD_ERROR, this);
            return;
        }
        
        this.$startLoad();
        
        this.dispatchEvent(Load.EVENT_LOAD_START, this);
    }
    
    /**
        Unloads a file that has previously loaded, or cancels a currently loading file from completing.
        
        @usageNote If you issue this command while a file is loading, event <code>onLoadError</code> is also invoked.
    */
    public function stop():Void {
        if (this.isLoading()) {
            this.$stopLoad();
            this.dispatchEvent(Load.EVENT_LOAD_ERROR, this);
            return;
        }
        
        this.$stopLoad();
    }
    
    public function getFilePath():String {
        return this.$filePath;
    }
    
    public function hasLoaded():Boolean {
        return this.$hasLoaded;
    }
    
    public function isLoading():Boolean {
        return this.$isLoading;
    }
    
    public function destroy():Void {
        this.$clean();
        
        delete this.$hasLoaded;
        delete this.$filePath;
        delete this.$target;
        
        super.destroy();
    }
    
    /**
        <strong>This function needs to be extended by a subclass.</strong>
    */
    private function $startLoad():Void {
        this.$isLoading = true;
        this.$hasLoaded = false;
    }
    
    /**
        <strong>This function needs to be extended by a subclass.</strong>
    */
    private function $stopLoad():Void {
        this.$clean();
        this.$hasLoaded = false;
    }
    
    /**
        <strong>This function needs to be called by a subclass.</strong>
        
        If target in subclass has an reliable <code>"onLoad"</code> handler call this method after target is defined in the constructor.
        
        @param loadContainer: <strong>[optional]</strong> Defines object file is loading into and has the event handler <code>"onLoad"</code>; defaults to <code>$target</code>.
    */
    private function $remapOnLoadHandler(loadContainer:Object):Void {
        var _this:Load  = this;
        var targ:Object = (loadContainer == undefined) ? this.$target : loadContainer;
        
        targ.onLoad = function(success:Boolean):Void {
            _this.$onLoad(success);
        };
    }
    
    private function $onLoad(success:Boolean):Void {
        if (success)
            this.$onComplete();
    }
    
    /**
        @sends onLoadComplete = function(sender:Load) {}
        @sends onLoadError = function(sender:Load) {}
    */
    private function $onComplete():Void {
        this.$hasLoaded = true;
        
        this.dispatchEvent(Load.EVENT_LOAD_COMPLETE, this);
        
        this.$frameDelay = new FrameDelay(this, '$onInitialized');
        this.$frameDelay.start();
    }
    
    /**
        @sends onLoadInit = function(sender:Load) {}
    */
    private function $onInitialized():Void {
        this.dispatchEvent(Load.EVENT_LOAD_INIT, this);
        this.$clean();
    }
    
    private function $clean():Void {
        this.$frameDelay.destroy();
        
        delete this.$frameDelay;
        delete this.$isLoading;
    }
}

Base load class. Class needs to be extended further to function properly.

Since:

Flash Player 7

Events broadcasted to listeners:

onLoadStart = function (sender:Load) {}
onLoadComplete = function (sender:Load) {}
onLoadError = function (sender:Load) {}
onLoadInit = function (sender:Load) {}

Summary

Class properties

EVENT_LOAD_START : String
EVENT_LOAD_ERROR : String
EVENT_LOAD_COMPLETE : String
EVENT_LOAD_INIT : String

Instance methods

start : Void
- Begins the loading process and broadcasts events to observers.
stop : Void
- Unloads a file that has previously loaded, or cancels a currently loading file from completing.
getFilePath : String
- Retrieves the path to the file that is to be loaded.
hasLoaded : Boolean
- Determines whether the requested file has finished loading.
isLoading : Boolean
- Determines whether the requested file is in the process of loading.
destroy : Void
- Removes any internal variables, intervals, enter frames, internal MovieClips and event observers to allow the object to be garbage collected.

Instance methods inherited from EventDispatcher

addEventObserver destroy dispatchEvent removeAllEventObservers removeEventObserver removeEventObserversForEvent removeEventObserversForScope

Instance methods inherited from CoreObject

$setClassDescription destroy toString

Class properties

EVENT_LOAD_COMPLETE

static EVENT_LOAD_COMPLETE:String = 'onLoadComplete'

(read,write)

EVENT_LOAD_ERROR

static EVENT_LOAD_ERROR:String = 'onLoadError'

(read,write)

EVENT_LOAD_INIT

static EVENT_LOAD_INIT:String = 'onLoadInit'

(read,write)

EVENT_LOAD_START

static EVENT_LOAD_START:String = 'onLoadStart'

(read,write)

Instance methods

destroy

function destroy (

) : Void

Removes any internal variables, intervals, enter frames, internal MovieClips and event observers to allow the object to be garbage collected.

Always call filePath before deleting last object pointer.

Overrides: