问题
I am aiming to create an application where the user can take a picture of their face, which includes an overlay of a face cutout. I need the user to be able to click the screen and for the application to save the picture, mask it with the same face cutout, and then save it to the applications storage.
This is the first time using AIR on IOS with Actionscript3. I know there is a proper directory that you are supposed to save to on IOS however I am not aware of it. I have been saving other variables using SharedObjects...
E.g:
var so:SharedObject = SharedObject.getLocal("applicationID");
and then writing to it
so.data['variableID'] = aVariable;
This is how I access the front camera and display it. For some reason to display the whole video and not a narrow section of it, I add the video from the camera to a movieclip on the stage, 50% of the size of the stage.
import flash.media.Camera;
import flash.media.Video;
import flash.display.BitmapData;
import flash.utils.ByteArray;
import com.adobe.images.JPGEncoder
var camera:Camera = Camera.getCamera("1");
camera.setQuality(0,100);
camera.setMode(1024,768, 30, false);
var video:Video = new Video();
video.attachCamera(camera);
videoArea.addChild(video);
Multitouch.inputMode = MultitouchInputMode.TOUCH_POINT;
Capture_Picture_BTN.addEventListener(TouchEvent.TOUCH_TAP, savePicture);
function savePicture(event:TouchEvent):void
{
trace("Saving Picture");
//Capture Picture BTN
var bitmapData:BitmapData = new BitmapData(1024,768);
bitmapData.draw(video);
}
I apologize if this is the wrong way of going about this I am still fairly new to Actionscript as it is. If you need any more information I will be happy to provide.
回答1:
You can only save ~100kb of data via SharedObject, so you can't use that. It is meant solely to save application settings and, from my experience, is ignored by AIR devs because we have better control over the file system.
We have the File and FileStream classes. These classes allow you to read and write directly to and from the device's disk, something not quite possible on the web (the user is the one who has to save/open; can't be done automatically).
Before my example, I must stress that you should read the documentation. Adobe's LiveDocs are among the best language/SDK docs available and it will point out many things that my quick example on usage will not (such as in-depth discussion of each directory, how to write various types, etc)
So, here's an example:
// create the File and resolve it to the applicationStorageDirectory, which is where you should save files
var f:File = File.applicationStorageDirectory.resolvePath("name.png");
// this prevents iCloud backup. false by default. Apple will reject anything using this directory for large file saving that doesn't prevent iCloud backup. Can also use cacheDirectory, though certain aspects of AIR cannot access that directory
f.preventBackup = true;
// set up the filestream
var fs:FileStream = new FileStream();
fs.open(f, FileMode.WRITE); //open file to write
fs.writeBytes( BYTE ARRAY HERE ); // writes a byte array to file
fs.close(); // close connection
So that will save to disk. To read, you open the FileStream in READ mode.
var fs:FileStream = new FileStream();
var output:ByteArray = new ByteArray();
fs.open(f, FileMode.READ); //open file to write
fs.readBytes( output ); // reads the file into a byte array
fs.close(); // close connection
Again, please read the documentation. FileStream supports dozens of read and write methods of various types. You need to select the correct one for your situation (readBytes() and writeBytes() should work in all cases, though there are instances where you are should use a more specific method)
Hope that helps.
来源：https://stackoverflow.com/questions/20622254/saving-and-masking-webcam-still-as3-air-ios