android - ActionScript 3 + AIR + Android = 如何下载 png 文件？在哪里存放？

Question

使用 Android 版 Air+AS3 时，如何从服务器下载 png？

另外，我在哪里存储它以便以后可以使用它而无需再次下载？

问候米尔扎

Answer 1

1. 更好地将您的文件存储在 ApplicationStoragePath 中，这样您就可以避免一些安全（访问被拒绝）问题。

2. 确保 writeBytesToFile() 也需要指定带有文件扩展名的文件路径（如“images/first.png”）

   private function download(url:String):void
   {
       var urlRequest:URLRequest = new URLRequest();
       urlRequest.url = url;
   
       var urlStream:URLStream = new URLStream();
       urlStream.addEventListener(Event.COMPLETE,onDownload_CompleteHandler);
       urlStream.addEventListener(IOErrorEvent.IO_ERROR, onDownload_IOErrorHandler);
       urlStream.addEventListener(HTTPStatusEvent.HTTP_RESPONSE_STATUS,onDownload_ResponseStatusHandler);
       urlStream.addEventListener(SecurityErrorEvent.SECURITY_ERROR,onDownload_SecurityHandler);   
       urlStream.load(urlRequest); 
   }
   
   protected function onDownload_CompleteHandler(event:Event):void
   {
       var urlStream:URLStream = event.currentTarget as URLStream;
       var outBytes:ByteArray = new ByteArray;         
       urlStream.readBytes(outBytes,0,urlStream.bytesAvailable);           
       writeBytesToFile(outBytes);
   }   
   
   
   private function writeBytesToFile(outBytes:ByteArray):void
   {
       var fileToWrite:File = File.applicationStorageDirectory.resolvePath("path/to/store/filenamewithextension");//Where you want store 
   
       var fileStream:FileStream = new FileStream();  
       fileStream.addEventListener(Event.CLOSE, onFileStream_CloseHandler);
       fileStream.addEventListener(IOErrorEvent.IO_ERROR,onFileStream_IOErrorHandler);
       fileStream.openAsync(fileToWrite, FileMode.WRITE);  
       fileStream.writeBytes(outBytes, 0, outBytes.length);
       fileStream.close();
   }
   
   protected function onFileStream_CloseHandler(event:Event = null):void
   {
       trace("File successfully downloaded ");                 
   }
   
   protected function onFileStream_IOErrorHandler(event:IOErrorEvent):void
   {
       trace("File can't downloaded file doesn't exist ");
   }
   
   protected function onDownload_SecurityHandler(event:SecurityErrorEvent):void
   {
       logger.error("onDownload_SecurityHandler :: " + event.text);            
   }
   
   protected function onDownload_ResponseStatusHandler(event:HTTPStatusEvent):void
   {
       trace("onDownload_ResponseStatusHandler :: " + event.status);
   }
   
   protected function onDownload_IOErrorHandler(event:IOErrorEvent):void
   {
       trace("onDownload_IOErrorHandler :: " + event.text);            
   }