Question

I started reading this tutorial: http://active.tutsplus.com/tutorials/actionscript/creating-a-reusable-flash-uploader-with-actionscript-3-0-and-php/

I’m using FlashDevelop, and I pasted the full code into an ActionScript file. The errors I’m receiving are like this:

C:\Users\tempus\Documents\uploaderas\Uploader.as(30): col: 4 Error: Access of undefined property select_btn.
select_btn.addEventListener( MouseEvent.CLICK, browse );
^
C:\Users\tempus\Documents\uploaderas\Uploader.as(31): col: 4 Error: Access of undefined property progress_mc.
progress_mc.bar.scaleX = 0;

...

I understand that the errors appear because the objects have not been declared ( and they appear to be instantiated from somewhere ), but I don’t understand how/what should I include to declare them. Could you point me towards a solution?

Answer 1

It’s because the buttons are created in the Flash IDE (as the tutorial was meant to be compiled using the Flash IDE). Since the buttons don’t exist in the code aspect you get that error.

You can either create the elements yourself via code, or use the Flash IDE and export a swc/swf of the neccessary UI elements and include that in your flashDevelop project. I’m assuming you’ll want to do the latter –

in the Flash IDE, open the .fla, open the library panel, find the progress asset, right click it and bring up the properties. Check the “Export For ActionScript” option, then in the ‘Class’ field give it a unique name like “SelectBtn”. Do the same for the ‘progress’ asset (only a different class name like ‘ProgressBar’). Go to the flash publish settings, and on the flash tab select ‘export swc’. publish the file and place the published swc in your flash Develop project folder (traditionally the lib folder of your project).

In Flash Develop, right click your swc and choose ‘Add To Library’. (You may need to right-click again and go to options and choose the include completely option). Now you can access those classes you setup in Flash. Then in your code, declare and initialize the display assets:

public var select_btn:SelectBtn = new SelectBtn();
public var progress_mc:ProgressBar = new ProgressBar();

You’ll also need to do that textField too. It would be easiest just to do it in your code though.

public var label_txt:TextField = new TextField();

Keep in mind you’ll need to manually position and use addChild on all three elements this way. If you want to keep the positioning that’s in flash, just select all the elements on the stage and press F8 to convert them to a MovieClip. Then in the library setup linkage the same as the others and give it a class name of something like “DisplayAssets” and export a new swc. Then your code would look like this:

public var select_btn:Sprite;
public var progress_mc:Sprite;

public function Uploader(){
    var displayAssets:DisplayAssets = new DisplayAssets();
    addChild(displayAssets);

    select_btn = displayAssets.select_btn;
    progress_mc = displayAssets.progress_mc;

    //the rest of the code
}