Two questions about loading and parsing air files

Because it is necessary to drag into the loading price resolution, so the first thought is the air, the code found on the internet is as follows:

Public class darg extends Sprite
{
Public Function darg ()
{
If (stage ){
Creat ();
} Else {
Addeventlistener (event. added_to_stage, creat );
}
}
Private VaR _ sp: SPRITE = new sprite ();
Private VaR _ format: array = [". jpg ",". jpg ",". JPEG ",". JPEG ",". GIF ",". GIF ",". PNG ",". SWF ",". PNG "];
Protected function creat (Event: event = NULL): void
{
_ Sp. Graphics. beginfill (0xff0000, 0.5 );
_ Sp. Graphics. drawrect (0, 0, stage. stagewidth, stage. stageheight );
_ Sp. Graphics. endfill ();
Addchild (_ Sp );
Stage. addeventlistener (nativedragevent. native_drag_enter, ondrop );
Stage. addeventlistener (nativedragevent. native_drag_drop, ondrop );
}

Private var Loader: loader = new loader;
Protected function ondrop (Event: nativedragevent): void
{
// Obtain the dragged file in array format, and specify that the dragged data is in file array format.
VaR files: array = event. clipboard. getdata (clipboardformats. file_list_format) as array;
// Obtain the first file to be dragged.
Var file: file = file (files [0]);
Switch (event. Type ){
Case nativedragevent. native_drag_enter:
If (_ format. indexof (file. Type )! =-1 ){
Nativedragmanager. acceptdragdrop (this );
}
Break;
Case nativedragevent. native_drag_drop:
If (_ format. indexof (file. Type )! =-1 ){
// Delete the uploaded Image
Loader. Unload ();
// Load the dragged Image
Loader. Load (New URLRequest (file. url ));
Removechild (_ Sp );
Addchild (loader );
}
Break;
}
}

 

Two issues to be aware:

1. There must be something on the stage, that is why the sprite should be added to the Code;

2. addchild is required, but not stage. addchild is added to the current scenario, rather than to the underlying stage. If you can listen to native_drag_enter on the stage, but there is no native_drag_drop event, you have not studied the specific cause. If you know, you can post it.