I am currently trying to write an android app in which a user can blacklist any food ingredients he or she wants to avoid. The user should then be able to scan a label and instantly be told whether or not any blacklisted ingredients are found via text recognition.
I am using a cameraSource to detect the text in real time which appears to somewhat work, but only when very few words are present on screen. When there are too many words on screen, it cannot find anything.
What is going wrong when larger amounts of words are present?
private SurfaceView cameraView;
private TextView textView;
private CameraSource cameraSource;
private const int RequestCameraPermissionID = 1001;
public JavaList<string> userIngredients;
public ISharedPreferences pref;
public ISharedPreferencesEditor edit;
public Bitmap imageBitmap;
protected override void OnCreate(Bundle bundle)
{
base.OnCreate(bundle);
// Set our view from the "main" layout resource
SetContentView(Resource.Layout.ScanLayout);
cameraView = FindViewById<SurfaceView>(Resource.Id.surface_view);
textView = FindViewById<TextView>(Resource.Id.text_view);
pref = Application.Context.GetSharedPreferences("UserPrefs", FileCreationMode.Private);
edit = pref.Edit();
var preferences = pref.GetStringSet("UserPrefs", new JavaList<string>());
userIngredients = new JavaList<string>(preferences);
var bitmapOptions = new BitmapFactory.Options();
TextRecognizer textRecognizer = new TextRecognizer.Builder(ApplicationContext).Build();
if (!textRecognizer.IsOperational)
{
Log.Error("Main Activity", "Detector dependancies are not yet available");
}
else
{
cameraSource = new CameraSource.Builder(ApplicationContext, textRecognizer)
.SetFacing(CameraFacing.Back)
.SetRequestedFps(2.0f)
.SetAutoFocusEnabled(true)
.Build();
cameraView.Holder.AddCallback(this);
textRecognizer.SetProcessor(this);
}
}
public void SurfaceCreated(ISurfaceHolder holder)
{
if (ActivityCompat.CheckSelfPermission(ApplicationContext, Manifest.Permission.Camera) != Android.Content.PM.Permission.Granted)
{
//Request Permission
ActivityCompat.RequestPermissions(this, new string[] {
Android.Manifest.Permission.Camera
}, RequestCameraPermissionID);
return;
}
cameraSource.Start(cameraView.Holder);
}
public void SurfaceDestroyed(ISurfaceHolder holder)
{
cameraSource.Stop();
}
public void ReceiveDetections(Detections detections)
{
bool blackListedFound = false;
SparseArray items = detections.DetectedItems;
if (items.Size() != 0)
{
textView.Post(() =>
{
for (int i = 0; i < items.Size(); ++i)
{
for (int j = 0; j < userIngredients.Size(); j++)
{
if (((TextBlock)items.ValueAt(i)).Value.Equals(userIngredients[j]))
{
blackListedFound = true;
textView.Text = "Not reccomended\nIngredient Found: " + userIngredients[j];
}
}
}
});
}
else if (blackListedFound == false)
textView.Post(() =>
{
textView.Text = "No Ingredients found";
});
}
}
}
Here are some example images of my current problem;
Here is an example of the app failing to find a blacklisted ingredient (Water);
So hi to #ll this is my fist post/question on stackoverflow :D
I need help # following :
So i integrated the Facebook SDk sucessfully in my game but i´dont get the profile picture working ...
So i tryied it oldshool on Facebooks "Tutotial" Way and followed all steps to implement login functions and so on ...
I´ve downloaded the "friendsmash_start" Sample and implemented that Stuff ...
My Main Problem is i don´t get ahead with this problem and can´t figure out what i´m doing wrong so i´m hoping for help.
Here´s the complete Code from the MainMenu Script from the sample which is the only i´ve changed ... like in the tutorial ...
Unity shows me this Error -> "The name 'LoadPicture' does not exist in the current context ... so the errors are on these two parts of code :
"LoadPicture(Util.GetPictureURL("me", 128, 128), MyPictureCallback);" in the "OnLoggedIn" function
"LoadPicture(Util.GetPictureURL("me", 128, 128), MyPictureCallback);" in the "MyPictureCallback" function
I don´t understand it cause i searched myself in the script for this function "LoadPicture" and find nothing that was ... according to the "Tutorial" of facebook here :
https://developers.facebook.com/docs/games/unity/unity-tutorial?locale=de_DE
the function should be there cause they wrote there :
"Take a look at the LoadPicture method also in MainMenu.cs to see how we use the Unity WWW class to load the image returned by the graph API."
But i can´t find it :(
HOPE SOMEONE CAN HELP ME I DON´T GET IT ...
Have that problem unfortunately very long time ... thats enoying. :(
HERE`S THE FULL CODE OF MAINMENU.CS :
using UnityEngine;
using System.Collections;
using System.Collections.Generic;
using Facebook.MiniJSON;
using System;
public class MainMenu : MonoBehaviour
{
// Inspector tunable members //
public Texture ButtonTexture;
public Texture PlayTexture; // Texture for main menu button icons
public Texture BragTexture;
public Texture ChallengeTexture;
public Texture StoreTexture;
public Texture FullScreenTexture;
public Texture FullScreenActiveTexture;
public Texture ResourcesTexture;
public Vector2 CanvasSize; // size of window on canvas
public Rect LoginButtonRect; // Position of login button
public Vector2 ResourcePos; // position of resource indicators (not used yet)
public Vector2 ButtonStartPos; // position of first button in main menu
public float ButtonScale; // size of main menu buttons
public float ButtonYGap; // gap between buttons in main menu
public float ChallengeDisplayTime; // Number of seconds the request sent message is displayed for
public Vector2 ButtonLogoOffset; // Offset determining positioning of logo on buttons
public float TournamentStep; // Spacing between tournament entries
public float MouseScrollStep = 40; // Amount score table moves with each step of the mouse wheel
public PaymentDialog paymentDialog;
public GUISkin MenuSkin;
public int CoinBalance;
public int NumLives;
public int NumBombs;
public Texture[] CelebTextures;
public string [] CelebNames;
// Private members //
private static MainMenu instance;
private static List<object> friends = null;
private static Dictionary<string, string> profile = null;
private static List<object> scores = null;
private static Dictionary<string, Texture> friendImages = new Dictionary<string, Texture>();
private Vector2 scrollPosition = Vector2.zero;
private bool haveUserPicture = false;
private float tournamentLength = 0;
private int tournamentWidth = 512;
private int mainMenuLevel = 0; // Level index of main menu
private string popupMessage;
private float popupTime;
private float popupDuration;
void Awake()
{
Util.Log("Awake");
paymentDialog = ((PaymentDialog)(GetComponent("PaymentDialog")));
// allow only one instance of the Main Menu
if (instance != null && instance != this)
{
Destroy(gameObject);
return;
}
#if UNITY_WEBPLAYER
// Execute javascript in iframe to keep the player centred
string javaScript = #"
window.onresize = function() {
var unity = UnityObject2.instances[0].getUnity();
var unityDiv = document.getElementById(""unityPlayerEmbed"");
var width = window.innerWidth;
var height = window.innerHeight;
var appWidth = " + CanvasSize.x + #";
var appHeight = " + CanvasSize.y + #";
unity.style.width = appWidth + ""px"";
unity.style.height = appHeight + ""px"";
unityDiv.style.marginLeft = (width - appWidth)/2 + ""px"";
unityDiv.style.marginTop = (height - appHeight)/2 + ""px"";
unityDiv.style.marginRight = (width - appWidth)/2 + ""px"";
unityDiv.style.marginBottom = (height - appHeight)/2 + ""px"";
}
window.onresize(); // force it to resize now";
Application.ExternalCall(javaScript);
#endif
DontDestroyOnLoad(gameObject);
instance = this;
// Initialize FB SDK
FB.Init(SetInit, OnHideUnity);
}
private void SetInit()
{
Util.Log("SetInit");
enabled = true; // "enabled" is a property inherited from MonoBehaviour
if (FB.IsLoggedIn)
{
Util.Log("Already logged in");
OnLoggedIn();
}
}
private void OnHideUnity(bool isGameShown)
{
Util.Log("OnHideUnity");
if (!isGameShown)
{
// pause the game - we will need to hide
Time.timeScale = 0;
}
else
{
// start the game back up - we're getting focus again
Time.timeScale = 1;
}
}
private void QueryScores()
{
FB.API("/app/scores?fields=score,user.limit(20)", Facebook.HttpMethod.GET, ScoresCallback);
}
private int getScoreFromEntry(object obj)
{
Dictionary<string,object> entry = (Dictionary<string,object>) obj;
return Convert.ToInt32(entry["score"]);
}
void ScoresCallback(FBResult result)
{
Util.Log("ScoresCallback");
if (result.Error != null)
{
Util.LogError(result.Error);
return;
}
scores = new List<object>();
List<object> scoresList = Util.DeserializeScores(result.Text);
foreach(object score in scoresList)
{
var entry = (Dictionary<string,object>) score;
var user = (Dictionary<string,object>) entry["user"];
string userId = (string)user["id"];
if (string.Equals(userId,FB.UserId))
{
// This entry is the current player
int playerHighScore = getScoreFromEntry(entry);
Util.Log("Local players score on server is " + playerHighScore);
if (playerHighScore < GameStateManager.Score)
{
Util.Log("Locally overriding with just acquired score: " + GameStateManager.Score);
playerHighScore = GameStateManager.Score;
}
entry["score"] = playerHighScore.ToString();
GameStateManager.HighScore = playerHighScore;
}
scores.Add(entry);
if (!friendImages.ContainsKey(userId))
{
// We don't have this players image yet, request it now
LoadPictureAPI(Util.GetPictureURL(userId, 128, 128),pictureTexture =>
{
if (pictureTexture != null)
{
friendImages.Add(userId, pictureTexture);
}
});
}
}
// Now sort the entries based on score
scores.Sort(delegate(object firstObj,
object secondObj)
{
return -getScoreFromEntry(firstObj).CompareTo(getScoreFromEntry(secondObj));
}
);
}
void OnApplicationFocus( bool hasFocus )
{
Util.Log ("hasFocus " + (hasFocus ? "Y" : "N"));
}
// Convenience function to check if mouse/touch is the tournament area
private bool IsInTournamentArea (Vector2 p)
{
return p.x > Screen.width-tournamentWidth;
}
// Scroll the tournament view by some delta
private void ScrollTournament(float delta)
{
scrollPosition.y += delta;
if (scrollPosition.y > tournamentLength - Screen.height)
scrollPosition.y = tournamentLength - Screen.height;
if (scrollPosition.y < 0)
scrollPosition.y = 0;
}
// variables for keeping track of scrolling
private Vector2 mouseLastPos;
private bool mouseDragging = false;
void Update()
{
if(Input.touches.Length > 0)
{
Touch touch = Input.touches[0];
if (IsInTournamentArea (touch.position) && touch.phase == TouchPhase.Moved)
{
// dragging
ScrollTournament (touch.deltaPosition.y*3);
}
}
if (Input.GetAxis("Mouse ScrollWheel") < 0)
{
ScrollTournament (MouseScrollStep);
}
else if (Input.GetAxis("Mouse ScrollWheel") > 0)
{
ScrollTournament (-MouseScrollStep);
}
if (Input.GetMouseButton(0) && IsInTournamentArea(Input.mousePosition))
{
if (mouseDragging)
{
ScrollTournament (Input.mousePosition.y - mouseLastPos.y);
}
mouseLastPos = Input.mousePosition;
mouseDragging = true;
}
else
mouseDragging = false;
}
// Button drawing logic //
private Vector2 buttonPos; // Keeps track of where we've got to on the screen as we draw buttons
private void BeginButtons()
{
// start drawing buttons at the chosen start position
buttonPos = ButtonStartPos;
}
private bool DrawButton(string text, Texture texture)
{
// draw a single button and update our position
bool result = GUI.Button(new Rect (buttonPos.x,buttonPos.y, ButtonTexture.width * ButtonScale, ButtonTexture.height * ButtonScale),text,MenuSkin.GetStyle("menu_button"));
Util.DrawActualSizeTexture(ButtonLogoOffset*ButtonScale+buttonPos,texture,ButtonScale);
buttonPos.y += ButtonTexture.height*ButtonScale + ButtonYGap;
if (paymentDialog.DialogEnabled)
result = false;
return result;
}
void OnGUI()
{
GUI.skin = MenuSkin;
if (Application.loadedLevel != mainMenuLevel) return; // don't display anything except when in main menu
GUILayout.Box("", MenuSkin.GetStyle("panel_welcome"));
if (!FB.IsLoggedIn)
{
GUI.Label((new Rect(179, 11, 287, 160)), "Login to Facebook", MenuSkin.GetStyle("text_only"));
if (GUI.Button(LoginButtonRect, "", MenuSkin.GetStyle("button_login")))
{
FB.Login("email,publish_actions", LoginCallback);
}
}
if (FB.IsLoggedIn)
{
string panelText = "Welcome ";
panelText += (!string.IsNullOrEmpty(GameStateManager.Username)) ? string.Format("{0}!", GameStateManager.Username) : "Smasher!";
if (GameStateManager.UserTexture != null)
GUI.DrawTexture( (new Rect(8,10, 150, 150)), GameStateManager.UserTexture);
GUI.Label( (new Rect(179 , 11, 287, 160)), panelText, MenuSkin.GetStyle("text_only"));
}
string subTitle = "Let's smash some friends!";
if (GameStateManager.Score > 0)
{
subTitle = "Score: " + GameStateManager.Score.ToString();
}
if (!string.IsNullOrEmpty(subTitle))
{
GUI.Label( (new Rect(132, 28, 400, 160)), subTitle, MenuSkin.GetStyle("sub_title"));
}
BeginButtons();
if (DrawButton("Play",PlayTexture))
{
onPlayClicked();
}
if (FB.IsLoggedIn)
{
// Draw resources bar
Util.DrawActualSizeTexture(ResourcePos,ResourcesTexture);
Util.DrawSimpleText(ResourcePos + new Vector2(47,5) ,MenuSkin.GetStyle("resources_text"),string.Format("{0}",CoinBalance));
Util.DrawSimpleText(ResourcePos + new Vector2(137,5) ,MenuSkin.GetStyle("resources_text"),string.Format("{0}",NumBombs));
Util.DrawSimpleText(ResourcePos + new Vector2(227,5) ,MenuSkin.GetStyle("resources_text"),string.Format("{0}",NumLives));
}
#if UNITY_WEBPLAYER
if (Screen.fullScreen)
{
if (DrawButton("Full Screen",FullScreenActiveTexture))
SetFullscreenMode(false);
}
else
{
if (DrawButton("Full Screen",FullScreenTexture))
SetFullscreenMode(true);
}
#endif
DrawPopupMessage();
}
public void AddPopupMessage(string message, float duration)
{
popupMessage = message;
popupTime = Time.realtimeSinceStartup;
popupDuration = duration;
}
public void DrawPopupMessage()
{
if (popupTime != 0 && popupTime + popupDuration > Time.realtimeSinceStartup)
{
// Show message that we sent a request
Rect PopupRect = new Rect();
PopupRect.width = 800;
PopupRect.height = 100;
PopupRect.x = Screen.width / 2 - PopupRect.width / 2;
PopupRect.y = Screen.height / 2 - PopupRect.height / 2;
GUI.Box(PopupRect,"",MenuSkin.GetStyle("box"));
GUI.Label(PopupRect, popupMessage, MenuSkin.GetStyle("centred_text"));
}
}
void TournamentGui()
{
GUILayout.BeginArea(new Rect((Screen.width - 450),0,450,Screen.height));
// Title box
GUI.Box (new Rect(0, - scrollPosition.y, 100,200), "", MenuSkin.GetStyle("tournament_bar"));
GUI.Label (new Rect(121 , - scrollPosition.y, 100,200), "Tournament", MenuSkin.GetStyle("heading"));
Rect boxRect = new Rect();
if(scores != null)
{
var x = 0;
foreach(object scoreEntry in scores)
{
Dictionary<string,object> entry = (Dictionary<string,object>) scoreEntry;
Dictionary<string,object> user = (Dictionary<string,object>) entry["user"];
string name = ((string) user["name"]).Split(new char[]{' '})[0] + "\n";
string score = "Smashed: " + entry["score"];
boxRect = new Rect(0, 121+(TournamentStep*x)-scrollPosition.y , 100,128);
// Background box
GUI.Box(boxRect,"",MenuSkin.GetStyle("tournament_entry"));
// Text
GUI.Label (new Rect(24, 136 + (TournamentStep * x) - scrollPosition.y, 100,128), (x+1)+".", MenuSkin.GetStyle("tournament_position")); // Rank e.g. "1.""
GUI.Label (new Rect(250,145 + (TournamentStep * x) - scrollPosition.y, 300,100), name, MenuSkin.GetStyle("tournament_name")); // name
GUI.Label (new Rect(250,193 + (TournamentStep * x) - scrollPosition.y, 300,50), score, MenuSkin.GetStyle("tournament_score")); // score
Texture picture;
if (friendImages.TryGetValue((string) user["id"], out picture))
{
GUI.DrawTexture(new Rect(118,128+(TournamentStep*x)-scrollPosition.y,115,115), picture); // Profile picture
}
x++;
}
}
else GUI.Label (new Rect(180,270,512,200), "Loading...", MenuSkin.GetStyle("text_only"));
// Record length so we know how far we can scroll to
tournamentLength = boxRect.y + boxRect.height + scrollPosition.y;
GUILayout.EndArea();
}
// React to menu buttons //
private void onPlayClicked()
{
Util.Log("onPlayClicked");
if (friends != null && friends.Count > 0)
{
// Select a random friend and get their picture
Dictionary<string, string> friend = Util.RandomFriend(friends);
GameStateManager.FriendName = friend["first_name"];
GameStateManager.FriendID = friend["id"];
GameStateManager.CelebFriend = -1;
LoadPictureURL(friend["image_url"],FriendPictureCallback);
}
else
{
//We can't access friends
GameStateManager.CelebFriend = UnityEngine.Random.Range(0,CelebTextures.Length - 1);
GameStateManager.FriendName = CelebNames[GameStateManager.CelebFriend];
}
// Start the main game
Application.LoadLevel("GameStage");
GameStateManager.Instance.StartGame();
}
public void SetFullscreenMode (bool on)
{
if (on)
{
Screen.SetResolution (Screen.currentResolution.width, Screen.currentResolution.height, true);
}
else
{
Screen.SetResolution ((int)CanvasSize.x, (int)CanvasSize.y, false);
}
}
public static void FriendPictureCallback(Texture texture)
{
GameStateManager.FriendTexture = texture;
}
delegate void LoadPictureCallback (Texture texture);
IEnumerator LoadPictureEnumerator(string url, LoadPictureCallback callback)
{
WWW www = new WWW(url);
yield return www;
callback(www.texture);
}
void LoadPictureAPI (string url, LoadPictureCallback callback)
{
FB.API(url,Facebook.HttpMethod.GET,result =>
{
if (result.Error != null)
{
Util.LogError(result.Error);
return;
}
var imageUrl = Util.DeserializePictureURLString(result.Text);
StartCoroutine(LoadPictureEnumerator(imageUrl,callback));
});
}
void LoadPictureURL (string url, LoadPictureCallback callback)
{
StartCoroutine(LoadPictureEnumerator(url,callback));
}
void LoginCallback(FBResult result)
{
Util.Log("LoginCallback");
if (FB.IsLoggedIn)
{
OnLoggedIn();
}
}
void OnLoggedIn()
{
Util.Log("Logged in. ID: " + FB.UserId);
// Reqest player info and profile picture
FB.API("/me?fields=id,first_name,friends.limit(100).fields(first_name,id)", Facebook.HttpMethod.GET, APICallback);
LoadPicture(Util.GetPictureURL("me", 128, 128), MyPictureCallback);
}
void APICallback(FBResult result)
{
Util.Log("APICallback");
if (result.Error != null)
{
Util.LogError(result.Error);
// Let's just try again
FB.API("/me?fields=id,first_name,friends.limit(100).fields(first_name,id)", Facebook.HttpMethod.GET, APICallback);
return;
}
profile = Util.DeserializeJSONProfile(result.Text);
GameStateManager.Username = profile["first_name"];
friends = Util.DeserializeJSONFriends(result.Text);
}
void MyPictureCallback(Texture texture)
{
Util.Log("MyPictureCallback");
if (texture == null)
{
// Let's just try again
LoadPicture(Util.GetPictureURL("me", 128, 128), MyPictureCallback);
return;`
}
GameStateManager.UserTexture = texture;
}
}
change the word "LoadPicture" for "LoadPictureAPI".
For reference see:
https://github.com/fbsamples/friendsmash-unity/blob/master/friendsmash_payments_start/Assets/Scripts/MainMenu.cs
It appears that filtering an ObservableCollection with CollectionViewSource is not possible in WinRT:
See here!
I can filter using LINQ, but how do I get the UI to update if changes that affect the filtered data are made?
I ended up writing my own class to achieve the desired effect:
public class ObservableCollectionView<T> : ObservableCollection<T>
{
private ObservableCollection<T> _view;
private Predicate<T> _filter;
public ObservableCollectionView(IComparer<T> comparer)
: base(comparer)
{
}
public ObservableCollectionView(IComparer<T> comparer, IEnumerable<T> collection)
: base(comparer, collection)
{
}
public ObservableCollectionView(IComparer<T> comparer, IEnumerable<T> collection, Predicate<T> filter)
: base(comparer, collection == null ? new T[] { } : collection)
{
if (filter != null)
{
_filter = filter;
if (collection == null)
_view = new ObservableCollection<T>(comparer);
else
_view = new ObservableCollection<T>(comparer, collection);
}
}
public ObservableCollection<T> View
{
get
{
return (_filter == null ? this : _view);
}
}
public Predicate<T> Filter
{
get
{
return _filter;
}
set
{
if (value == null)
{
_filter = null;
_view = new ObservableCollection<T>(Comparer);
}
else
{
_filter = value;
Fill();
}
}
}
private void Fill()
{
_view = new ObservableCollection<T>(Comparer);
foreach (T item in this)
{
if (Filter(item))
View.Add(item);
}
}
private int this[T item]
{
get
{
int foundIndex = -1;
for (int index = 0; index < View.Count; index++)
{
if (View[index].Equals(item))
{
foundIndex = index;
break;
}
}
return foundIndex;
}
}
protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
{
base.OnCollectionChanged(e);
if (_filter != null)
{
switch (e.Action)
{
case NotifyCollectionChangedAction.Add:
foreach (T item in e.NewItems)
if (Filter(item))
View.Add(item);
break;
case NotifyCollectionChangedAction.Move:
break;
case NotifyCollectionChangedAction.Remove:
foreach (T item in e.OldItems)
if (Filter(item))
View.Remove(item);
break;
case NotifyCollectionChangedAction.Replace:
for (int index = 0; index < e.OldItems.Count; index++)
{
T item = (T)e.OldItems[index];
if (Filter(item))
{
int foundIndex = this[item];
if (foundIndex != -1)
View[foundIndex] = (T)e.NewItems[index];
}
}
break;
case NotifyCollectionChangedAction.Reset:
Fill();
break;
}
}
}
protected override void OnPropertyChanged(PropertyChangedEventArgs e)
{
base.OnPropertyChanged(e);
if (_filter != null)
{
// TODO: Implement code for property changes
}
}
}
Not yet perfect. So improvements/suggestions welcomed.
You can now bind this object, directly to a control using the View property.
You need to make sure the filtering changes are observable, so you can set the source of the CollectionViewSource to an ObservableCollection and make the changes on that collection or assign a new Source of the CVS to a new, filtered collection.
This is my first post here. I am trying to create a singly link list. I am using AtEnd and AtStart methods to insert values at the end or in the beginning of the list and using display method to print all the values. The insertion methods seems to be working fine (at least I think so) but whenever I call display method it shows only the first value and then there is a null pointer exception. For example when I run this code I see only 9 and then there is the NPE despite the fact that I have put a check on the display method for "not null".
class node {
private int data;
private node next;
node() {
}
node(int data) {
this.data = data;
this.next = null;
}
public int getData() {
return data;
}
public void setData(int data) {
this.data=data;
}
public node getNext() {
return next;
}
public void setNext(node next) {
this.next = next;
}
}
public class list extends node {
node head;
list() {
}
public void AtStart(int val) {
node n = new node(val);
if (head == null) {
head=n;
} else {
n.setNext(head);
int temp = head.getData();
head.setData(val);
n.setData(temp);
//n = head;
}
}
public void AtEnd(int val) {
if (head == null) {
node n = new node(val);
head = n;
} else {
node t = head;
for(; t.getNext() != null; ) {
if(t.getNext() == null) {
t.setNext(new node (val));
}
t = t.getNext();
}
}
}
public void display() {
node t = head;
for(; t.getNext() == null;) {
if (t !=null) {
System.out.println(t.getData());
t = t.getNext();
}
}
}
}
public static void main(String args[]) {
list l = new list();
l.AtStart(16);
l.AtEnd(6);
l.AtEnd(36);
l.AtStart(9);
l.AtEnd(22);
l.display();
}
i dont get what your AtStart function does, it should be much simpler:
public void AtStart(int val){
if(head==null){
head=n;
}
else{
head.setnext(head);
head.setData(val);
}
}
I am trying to create custom iterator element. The class itself is below.
public class ArrayBasedIterator implements IteratorInterface
{
// Holds Array of elements which are iterated
private var _container:Array;
// Holds current index
private var _index:uint = 0;
public function ArrayBasedIterator(data:Array)
{
if (!data)
throw new Error("Cannot create iterator for null data");
_container = data;
}
/**
* Returns next node if it exists, null otherwise*/
public function next():TreeNode
{
if (_index > _container.length )
{
return null;
}
else {
_index += 1;
}
//TODO: implement function
return _container[_index];
}
/**
* Returns prev node if it exists, null otherwise*/
public function prev():TreeNode
{
if (_index < 0)
{
return null
}
else {
_index -= 1;
}
//TODO: implement function
return _container[_index];
}
public function len():int
{
return _container.length;
}
}
The question is. In case I have such iterator over some elements, would it be possible to use for .... in structure? What do I need to change to use it? (Except using just array instead of iterator of course)
If you want to use for ... in, you'll need to subclass Proxy and override the appropriate methods:
http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/utils/Proxy.html