Develop Reference

Loading binary image data to an image fails on Android 4.1 in Cordova Project

I have serious issues loading binary image data into a simple image-element. I coded a cordova app (using Sencha touch) which loads images the following way:
xhr.open('GET', imageUrl, true);
xhr.responseType = 'blob';
xhr.addEventListener('load', function () {
if (xhr.status === 200) {
// onload needed since Google Chrome doesn't support addEventListener for FileReader
fileReader.onload = function (evt) {
image.setSrc(evt.target.result);
};
// Load blob as Data URL
fileReader.readAsDataURL(xhr.response);
}
}, false);
On Android 5 and 4.4 (these are the ones I tested) it works like a charm. Now I ran it Android 4.1 on an ASUS Tablet and the onload callback doesn't get fired. When I throw a blob in the readAsDataURL-function, at least the onload callback is fired, but the image doesn't show any image as well :(
Has anyone a suggestion, what the failure could be or what I'm doing wrong?

Ah, finally I got it to work on Android 4.1.1 (ASUS Tablet) with the following code. Another issue was, that saving an arraybuffer response from the xhr could not simply serialized, so I converted the stuff to string. Also I receive the blob taking into account, that on some systems the Blob object simply isn't there:
function arrayBufferToString(buf) {
return String.fromCharCode.apply(null, new Uint8Array(buf));
};
function stringToArrayBuffer(str) {
var buf = new ArrayBuffer(str.length*2); // 2 bytes for each char
var bufView = new Uint8Array(buf);
for (var i=0, strLen=str.length; i<strLen; i++) {
bufView[i] = str.charCodeAt(i);
}
return buf;
};
function getBlob(content, type) {
var blob = null;
// Android 4 only has the deprecated BlobBuilder :-(
try {
blob = new Blob([content], {type: type});
} catch(e) {
window.BlobBuilder = window.BlobBuilder || window.WebKitBlobBuilder ||
window.MozBlobBuilder || window.MSBlobBuilder;
if (window.BlobBuilder)
{
var bb = new BlobBuilder();
bb.append(content);
blob = bb.getBlob(type);
}
}
return blob;
};
cachedFile = getCachedFile(...); // not of interest here, I think :-)
if (cachedFile)
{
callback.apply(this, [window.webkitURL.createObjectURL(getBlob(stringToArrayBuffer(cachedFile.data), 'image/jpeg'))]);
}
else {
xhr.open('GET', imageUrl, true);
xhr.responseType = 'arraybuffer';
xhr.addEventListener('load', function () {
if (xhr.status === 200) {
cachedFile = {
url: imageUrl,
data: arrayBufferToString(xhr.response)
};
addCachedFile(cachedFile); // not of interest here, I think :-)
callback.apply(this, [window.webkitURL.createObjectURL(getBlob(xhr.response, 'image/jpeg'))]);
}
}, false);
// Send XHR
xhr.send();
}
Edit: Just did a little change and now used the Uint8Array Class instead of the Uint16Array Class because I got errors: "RangeError: byte length of Uint16Array should be a multiple of 2". Now it works well.
Edit2: Just saw, that the above code doesn't work out in all situations because of the usage of Uint8Array resp. Uint16Array.
Now I think I have a solid solution: I convert the binary responded by the image url into a base64 using canvas with the function from here http://appcropolis.com/blog/web-technology/javascript-encode-images-dataurl/ . Takes a little time, but still a working solution :)

Cordova resolveLocalFileSystemURL callbacks not fired

I've been trying to run the following code but the callbacks [ok() and ko()] are not called.
Using Worklight 6.2 (Cordova 3.4).
function wlCommonInit() {
window.requestFileSystem(LocalFileSystem.PERSISTENT, 0,
success, fail);
window.resolveLocalFileSystemURL(cordova.file.applicationDirectory
+ "www/index.html", ok, ko);
}
function ko(e) {
alert("NO");
}
function ok(fileEntry) {
alert("OK");
}
On the other hand requestFileSystem callbacks are called regularly.

The code snippet in the question will not work in Android due to a Cordova defect: https://issues.apache.org/jira/browse/CB-7273.
To progress further, it would help to understand what are your plans for the file itself.
Do you simply want the path to the file
Or do you want to alter the contents of the file?
Or?
You can read more about file system operations in Cordova in this question/answer: Where does LocalFileSystem.PERSISTENT point to?

I managed to access local fiiles in Worklight running an Android environment using a XMLHttpRequest:
//Works only on Android
function prendiCaricaRisorsaWorklight(percorsoPiuNomeFile) {
var xmlhttp = new XMLHttpRequest();
var risposta = "";
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4
&& (xmlhttp.status == 200 || xmlhttp.status == 0)) {
risposta = xmlhttp.responseText;
alert(risposta);
}
}
xmlhttp.open("GET", "file:///android_asset/www/default/"
+ percorsoPiuNomeFile, true);
xmlhttp.send(null);
}
Usage example:
prendiCaricaRisorsaWorklight("css/cssInterno.css");
prendiCaricaRisorsaWorklight("js/jsInterno.js");
This shows on Android an alert with the file content.

Android(AIR/Actionscript) Cant return FB access_token from stageWebView

Im simply trying to get my users access token from FB using stageWebView. When i trace the output from the location change/changing events all i get are google/FB urls, none of which have the token.
Here is my code:
var webView:StageWebView = new StageWebView();
function onChanging(e:LocationChangeEvent):void {
trace(e.location);
e.preventDefault();
webView.loadURL(e.location);
webView.stage = null;
}
function onChange(e:LocationChangeEvent):void {
trace(webView.location);
if(webView.location.indexOf("http://google.com") == 0 && webView.location.indexOf("access_token")!=-1) {
trace("?"+webView.location.substring(webView.location.indexOf("access_token"), webView.location.indexOf("&expires_in")));
webView.stage = null;
}
}
function connectFb() {
webView.addEventListener(LocationChangeEvent.LOCATION_CHANGING, onChanging);
webView.addEventListener(LocationChangeEvent.LOCATION_CHANGE, onChange);
webView.stage = stage;
webView.viewPort = new Rectangle(0, 0, stage.stageWidth, stage.stageHeight);
webView.loadURL("https://graph.facebook.com/oauth/authorize?client_id=123456789012345&redirect_uri=http://google.com&type=user_agent&display=popup")
}
My Codes output:
https://graph.facebook.com/oauth/authorize?client_id=164534120383085&redirect_uri=http://google.com&type=user_agent&display=popup
https://www.facebook.com/dialog/oauth?client_id=164534120383085&redirect_uri=http%3A%2F%2Fgoogle.com&type=user_agent&display=popup
https://www.facebook.com/dialog/oauth?client_id=164534120383085&redirect_uri=http%3A%2F%2Fgoogle.com&type=user_agent&display=popup
http://google.com/
http://google.com/
http://www.google.com/
http://www.google.com/
I tried every tutorial on the net and even bought a book on AS3 facebook dev & still cant figure this out; Any help would be VERY appreciated since this is a fairly important project to me

Use this where you are Updating UI example Loading Profile photo or Name of User
String acc = session.getAccessToken();
Log.e("Access-Token", acc);
Best of Luck

Air android/mobile: same sharedobject for different apps?

I have two apps, one is a trial version the other the full version of a game, both made with adobe air. While saving data via the sharedobjects solution is no problem, I would like to use "one" savegame for both appsm, so users can keep their progress when upgrading to the full version. I tried around a little. But code like e.g. ...:
SharedObject.getLocal("myApp","/");
... doesnt work. So the question is, is there a way to have two Air apps using the same shared object? Or maybe if not using, at least "read" the shared object of another Air app?
Thanks in advance,
ANB_Seth

The answer is yes, I actually made a game transfer system for iOS and Android via network connection and 6 digit hash the user has to enter in the newly installed app to fetch the SO from the server. You could do this with a simple file stored locally on the SD card or other local storage device.
/**
* send this user's current save data to the server
*/
public function send():void{
var ba:ByteArray = new ByteArray();
// Main.sv.user - is the registerClassAlias object we write/read locally via SharedObject
ba.writeObject(Main.sv.user);
var name:String = Crypto.hash("Random Secrect Salt - typically user score, name, etc.");
// create 6 digit hash
var key:String = Crypto.hash(name).slice(0, 6).toUpperCase();
var request:URLRequest = new URLRequest ( 'https://sharedobject.com/transfer/save/name/'+name+'/key/'+key );
var loader: URLLoader = new URLLoader();
request.contentType = 'application/octet-stream';
request.method = URLRequestMethod.POST;
request.data = ba;
loader.addEventListener(IOErrorEvent.IO_ERROR, function (evt:Event) {
trace("error - network");
onSaveRestoreEvent(1);
});
loader.addEventListener(Event.COMPLETE, function (evt:Event) {
addChild(new BaseDialog("Save Sent To Server", "Your data has been sent to the server. To get this data back from the server " +
"you will need your secret key. Please write this six digit key down:\n"+name));
});
loader.load( request );
}
/**
* create a GET SO dialog
*/
public function receive():void{
var text:Sprite = new Sprite();
var textInput:TextInput = new TextInput();
textInput.width = Constants.SCREEN_WIDTH-100;
textInput.y = -50;
text.addChild(textInput);
var dialog:BaseDialog = new BaseDialog("Enter Secret Save Key", "Please enter your six digit secret save key in the field below, then press \"Get\".\n\n",
"Get", function():void{
text.removeChildren();
var url:String = "https://sharedobject.com/transfer/get/name/"+textInput.text; //servlet url
var request:URLRequest = new URLRequest(url);
//get rid of the cache issue:
var urlVariables:URLVariables = new URLVariables();
urlVariables.nocache = new Date().getTime();
request.data = urlVariables;
request.method = URLRequestMethod.GET;
var loader:URLLoader = new URLLoader();
loader.dataFormat = URLLoaderDataFormat.BINARY;
loader.addEventListener(Event.COMPLETE, function (evt:Event) {
var loader:URLLoader = URLLoader(evt.target);
var bytes:ByteArray = loader.data as ByteArray;
bytes.position = 0;
if(bytes.length <= 10 || !(bytes.readObject() is User)){
onSaveRestoreEvent(2);
}else{
try{
bytes.position = 0;
Main.sv.user = (bytes.readObject() as User);
Main.sv.save();
onSaveRestoreEvent(0);
}
catch( e : EOFError ){
onSaveRestoreEvent(3);
}
}
});
loader.addEventListener(IOErrorEvent.IO_ERROR, function (evt:Event) {
trace("error - network");
onSaveRestoreEvent(1);
});
loader.load(request);
},
"Close", function():void{text.removeChildren();}, null, null, text);
dispatchEvent(new CreateBaseDialogEvent(dialog));
}
/**
* called after the restore save system is done
* #param prompt int [0 = complete][1 = error network][2 = error key][3 = error EOF]
*/
private function onSaveRestoreEvent(prompt:int):void{
var dialog:BaseDialog;
if(prompt == 0){
dialog = new BaseDialog("Restore Complete!", "All save data has been restored.");
}else if(prompt == 1){
dialog = new BaseDialog("Network Error!", "Please seek an internet connection and try again.");
}else if(prompt == 2){
dialog = new BaseDialog("Invalid Secret Key!", "The key you've entered seems to be invalid, or the save data has expired on the server. " +
"Data only lasts on the server for 24 hours.");
}else{
dialog = new BaseDialog("Error!", "There was an issue getting the file from the server. Please try the transfer again.");
}
dispatchEvent(new CreateBaseDialogEvent(dialog));
}

ASP.Net MVC HttpContext.User.Identity is getting lost

I have a really weird scenario that I'm stuck on. I have a ASP.Net MVC 4 app where I'm authenticating a user and creating an authCookie and adding it to the response's cookies then redirecting them to the target page:
if (ModelState.IsValid)
{
var userAuthenticated = UserInfo.AuthenticateUser(model.UserName, model.Password);
if (userAuthenticated)
{
var userInfo = UserInfo.FindByUserName(model.UserName);
//SERIALIZE AUTHENTICATED USER
var serializer = new JavaScriptSerializer();
var serializedUser = serializer.Serialize(userInfo);
var ticket = new FormsAuthenticationTicket(1, model.UserName, DateTime.Now, DateTime.Now.AddMinutes(30), false, serializedUser);
var hash = FormsAuthentication.Encrypt(ticket);
var authCookie = new HttpCookie(FormsAuthentication.FormsCookieName, hash) {Expires = ticket.Expiration};
Response.Cookies.Add(authCookie);
if (Url.IsLocalUrl(model.ReturnUrl) && model.ReturnUrl.Length > 1 && model.ReturnUrl.StartsWith("/") && !model.ReturnUrl.StartsWith("//") && !model.ReturnUrl.StartsWith("/\\"))
{
return Redirect(model.ReturnUrl);
}
var url = Url.Action("Index", "Course");
return Redirect(url);
}
ModelState.AddModelError("", "The user name or password provided is incorrect.");
}
This is working just fine in all browsers. I can login and access the secure pages in my app.
My client is requesting an android version of this app. So, I'm trying to figure out how to convert this app into an APK file. My first attempt is to create a simple index.html page with an iframe that targets the application. This works just fine in Firefox and IE 9. However, when accessing the index.html page that contains the iframe that points to the app via Chrome, I get past the login code above and the user gets redirected to the secure controller, but the secure controller has a custom attribute to make sure the user is authenticated:
public class RequiresAuthenticationAttribute : ActionFilterAttribute
{
public override void OnActionExecuting(ActionExecutingContext filterContext)
{
if (filterContext.HttpContext.User.Identity.IsAuthenticated) return;
if (filterContext.HttpContext.Request.Url == null) return;
var returnUrl = filterContext.HttpContext.Request.Url.AbsolutePath;
if (!filterContext.HttpContext.Request.Browser.IsMobileDevice)
{
filterContext.HttpContext.Response.Redirect(FormsAuthentication.LoginUrl + string.Format("?ReturnUrl={0}", returnUrl), true);
}
else
{
filterContext.HttpContext.Response.Redirect("/Home/Home", true);
}
}
}
My app is failing on: filterContext.HttpContext.User.Identity.IsAuthenticated. IsAuthenticated is always false, even though the user was authenticated in the code above.
Keep in mind this only happens when accessing the app via iframe in Chrome. If I access the app directly instead of via iframe, then everything works just fine.
Any ideas?
UPDATE:
My controller extends SecureController. In the constructor of SecureController I have the code that deserializes the user:
public SecureController()
{
var context = new HttpContextWrapper(System.Web.HttpContext.Current);
if (context.Request.Cookies[FormsAuthentication.FormsCookieName] != null)
{
var serializer = new JavaScriptSerializer();
var cookie = context.Request.Cookies[FormsAuthentication.FormsCookieName].Value;
var ticket = FormsAuthentication.Decrypt(cookie);
CurrentUser = serializer.Deserialize<UserInfo>(ticket.UserData);
}
else
{
CurrentUser = new UserInfo();
}
//if ajax request and session has expired, then force re-login
if (context.Request.IsAjaxRequest() && context.Request.IsAuthenticated == false)
{
context.Response.Clear();
context.Response.StatusCode = 401;
context.Response.Flush();
}
}

First, you should be deriving from AuthorizeAttribute, not an ActionFilterAttribute. Authorization attributes execute before the method is even called at a higher level of the pipeline, while ActionFilters execute much further down, and other attributes can execute before yours.
Secondly, you aren't showing the code you use to decrypt the ticket and set the IPrincipal and IIdentity. Since that's where the problem is, it's odd that you didn't include it.