Display Flex application instantly?

I'm working on a little project in Flex that's an application to upload images to a server. Since it's a pretty lightweight application (~40 kb in release version), I would like it to display instantly when the html page is loaded. But somehow there's a delay of up to 1-2 seconds before it shows up. I think it is a delay actually between the load and the display of the application, and I believe it could be removed.

However, I couldn't find a solution on how to shorten/remove the delay. First, I tried to disable the preloader, but this did nothing. There's actually a delay between a preloader shuts and the application displays (it is around 500 ms - 1 sec). My next guess was to write a custom preloader cl开发者_如何学编程ass to display at least an image of the application (even though it wouldn't be clickable, but at least something).

Any advice would be greatly appreciated.

use AS2 instead, you'll get simpler and lightweight

try to use swfloader of current version in as2

use this in flex4 e.g. Merged into code as here http://devgirl.files.wordpress.com/2010/04/screen-shot-2010-04-07-at-2-26-32-pm.png

Well i actually managed to get the desired behavior. Your comments were useful though.

Here's how. I implemented a custom preloader for my application, and in the constructor of the preloader I loaded an image (read: screenshot) of my application in a disabled state (so that user won't want to interact with it). I used the SnapShot Demo from this link - http://blogs.adobe.com/aharui/2010/01/custom_preloader_downloadprogr.html

Here's the code that I wrote for the preloader (most of is is from the link below, a cut version):

package {

import flash.display.Bitmap;
import flash.display.BitmapData;
import flash.display.DisplayObject;
import flash.display.Loader;
import flash.display.Sprite;
import flash.events.Event;
import flash.events.ProgressEvent;
import flash.net.URLRequest;
import flash.utils.ByteArray;
import mx.events.FlexEvent;
import mx.events.RSLEvent;
import mx.preloaders.IPreloaderDisplay;

public class SSPreloader extends Sprite implements IPreloaderDisplay
{        
    [ Embed(source="startup.png", mimeType="application/octet-stream") ]
    public var WelcomeScreenGraphic:Class;

    private var loader:Loader;
    public function SSPreloader() 
    {
        super();

        loader = new Loader();
        loader.contentLoaderInfo.addEventListener(Event.COMPLETE, onLoaderBytesLoaded);
        loader.loadBytes(new WelcomeScreenGraphic() as ByteArray);
    }

    public function onLoaderBytesLoaded(event : Event) : void
    {
        loader.contentLoaderInfo.removeEventListener(Event.COMPLETE, onLoaderBytesLoaded);
        if (event.target.content != null)
        {
            var image:DisplayObject = event.target.content as DisplayObject; 
            addChildAt(image,0);
        }
    }


    private var _backgroundAlpha:Number = 1;
    public function get backgroundAlpha():Number
    {
        if (!isNaN(_backgroundAlpha))
            return _backgroundAlpha;
        else
            return 1;
    }

    public function set backgroundAlpha(value:Number):void
    {
        _backgroundAlpha = value;
    }

    //----------------------------------
    //  backgroundColor
    //----------------------------------

    private var _backgroundColor:uint;
    public function get backgroundColor():uint
    {
        return _backgroundColor;
    }
    public function set backgroundColor(value:uint):void
    {
        _backgroundColor = value;
    }

    //----------------------------------
    //  backgroundImage
    //----------------------------------

    private var _backgroundImage:Object;
    public function get backgroundImage():Object
    {
        return _backgroundImage;
    }
    public function set backgroundImage(value:Object):void
    {
        _backgroundImage = value;
    }

    //----------------------------------
    //  backgroundSize
    //----------------------------------

    private var _backgroundSize:String = "";
    public function get backgroundSize():String
    {
        return _backgroundSize;
    }
    public function set backgroundSize(value:String):void
    {
        _backgroundSize = value;
    }

    //----------------------------------
    //  preloader
    //----------------------------------

    private var _preloader:Sprite;         
    public function set preloader(value:Sprite):void
    {
        _preloader = value;

        value.addEventListener(ProgressEvent.PROGRESS, progressHandler);    
        value.addEventListener(Event.COMPLETE, completeHandler);

        value.addEventListener(RSLEvent.RSL_ERROR, rslErrorHandler);

        value.addEventListener(FlexEvent.INIT_PROGRESS, initProgressHandler);
        value.addEventListener(FlexEvent.INIT_COMPLETE, initCompleteHandler);
    }

    //----------------------------------
    //  stageHeight
    //----------------------------------

    private var _stageHeight:Number = 375;
    public function get stageHeight():Number 
    {
        return _stageHeight;
    }
    public function set stageHeight(value:Number):void 
    {
        _stageHeight = value;
    }

    //----------------------------------
    //  stageWidth
    //----------------------------------

    private var _stageWidth:Number = 500;
    public function get stageWidth():Number 
    {
        return _stageWidth;
    }
    public function set stageWidth(value:Number):void 
    {
        _stageWidth = value;
    }

    //--------------------------------------------------------------------------
    //
    //  Methods:IPreloaderDisplay
    //
    //--------------------------------------------------------------------------

    public function initialize():void
    {
    }

    //--------------------------------------------------------------------------
    //
    //  Methods
    //
    //--------------------------------------------------------------------------

    private var lastBarWidth:Number = 0;
    protected function setDownloadProgress(completed:Number, total:Number):void
    {
    }

    protected function setInitProgress(completed:Number, total:Number):void
    {
    }

    protected function showDisplayForDownloading(elapsedTime:int,
                                                 event:ProgressEvent):Boolean
    {
        return false;
    }

    protected function showDisplayForInit(elapsedTime:int, count:int):Boolean
    {
        return false;
    }

    //--------------------------------------------------------------------------
    //
    //  Event handlers
    //
    //--------------------------------------------------------------------------

    protected function progressHandler(event:ProgressEvent):void
    {
    }

    protected function completeHandler(event:Event):void
    {
    }

    protected function rslErrorHandler(event:RSLEvent):void
    {
        _preloader.removeEventListener(ProgressEvent.PROGRESS,
            progressHandler);    

        _preloader.removeEventListener(Event.COMPLETE,
            completeHandler);

        _preloader.removeEventListener(RSLEvent.RSL_ERROR,
            rslErrorHandler);

        _preloader.removeEventListener(FlexEvent.INIT_PROGRESS,
            initProgressHandler);

        _preloader.removeEventListener(FlexEvent.INIT_COMPLETE,
            initCompleteHandler);
    }

    protected function initProgressHandler(event:Event):void
    {
    }

    protected function initCompleteHandler(event:Event):void
    {
        dispatchEvent(new Event(Event.COMPLETE)); 
    }
}    

}

I got a huge class eventually, but it does what its supposed to. Any comments on the code would be appreciated.