as3 PNGEncoder error | 易学教程

问题

I am trying to save my graphics using the PNG encoder, and I get two errors.

Scene 1, Layer 'canvas', Frame 2, Line 42, Column 12    1172: Definition PNGEncoder could not be found.

Scene 1, Layer 'canvas', Frame 2, Line 965, Column 24   1120: Access of undefined property PNGEncoder.

Here is all the code revolving saving:

     import PNGEncoder;                          [Recieves the first error]


function export():void
{
  var bmd:BitmapData = new BitmapData(board.width, board.height);

bmd.draw(board);

var ba:ByteArray = PNGEncoder.encode(bmd);   [Recieves the second error]

var file:FileReference = new FileReference();  

file.save(ba, "MyDrawing.png"); 
}


saveButton.addEventListener(MouseEvent.CLICK,save) 


 function save(e:MouseEvent):void
{
    export(); 
  }

I got this code from a tutorial, so I can't be too sure it is formated right. The tut said that PNGEncoder was an import but according to flash cs3 it is not. Can someone help me straighten this out? I labeled the parts giving me an error, thanks.

回答1:

You need to download the PNG Encoder and setup Flash to know where to find the new library (the process below can be used for any other externally downloaded SWC's you need to use in future)

1) Create a new folder called Flash_Addons (the path would be C:\Flash_Addons\ it's just to get you started for now, later change the setup to a prefered folder name/location)

2) Download the AS3 CoreLib (the "Download ZIP" option at bottom/right-hand side

3) Inside the Zip is a folder (I think its called "as3corelib-.93") copy that to your Flash_Addons folder so it's now a sub-folder.

4) Now to tell Flash where to find it.. In your CS got to Edit-->Preferences (CTRL+U shortcut) and click on "ActionScript" in Category list then when shown click ActionScript 3.0 Settings
Now you will see three boxes (Source path/ Library path/ External path).

(for these below, click "+" to add new entry, then either type path or click the folder icon to browse)
Source path: You want it to add.. C:\Flash_Addons\
Library path: You want it to add.. C:\Flash_Addons\as3corelib-.93\lib
(note: the "lib" folder contains the actual as3corelib.SWC file, that's why we put direct path to it. When you want to add any new SWC library just add path to the list of entries (example):
C:\Flash_Addons\as3corelib-.93\lib
C:\Flash_Addons\Useful_Library_Folder_of_SWC_file\
etc... etc..

Now you're ready to export PNG..

import com.adobe.images.PNGEncoder; //fixes the errors

saveButton.addEventListener(MouseEvent.CLICK, save)

function save(e:MouseEvent):void
{  export(); }

function export():void
{
  var bmd:BitmapData = new BitmapData(board.width, board.height);

  bmd.draw(board);

  var ba:ByteArray = PNGEncoder.encode(bmd); 
  var file:FileReference = new FileReference();  

  file.save(ba, "MyDrawing.png"); 

}

来源：https://stackoverflow.com/questions/24843663/as3-pngencoder-error

标签

actionscript-3

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