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  • How to get Media Picker Field via proxy record of many-to-many in orchard

    - by Sergey Schipanov
    I need to access mediapickerfield in Widget view. This field is relative to 'ActionPart'. I have a problem, when I create many-to-many relationships to display my 'ActionPart' in the widget. When I mapped many-to-many I take an 'ActionPart' and but cannot access the mediapickerfield. Records classes public class ActionPartRecord : ContentPartRecord { public virtual string Text { get; set; } public virtual double Price { get; set; } public virtual int TextPosX { get; set; } public virtual int TextPosY { get; set; } public virtual String TextSale { get; set; } public virtual int Color { get; set; } } public class ActionListRecord { public virtual int Id { get; set; } public virtual ActionPartRecord ActionPartRecord { get; set; } public virtual ActionWidgetPartRecord ActionWidgetPartRecord { get; set; } } public class ActionWidgetPartRecord : ContentPartRecord { public ActionWidgetPartRecord() { ActionList = new List<ActionListRecord>(); } public virtual IList<ActionListRecord> ActionList { get; set; } } public class ActionWidgetPart : ContentPart<ActionWidgetPartRecord> { public IEnumerable<ActionPartRecord> ActionList { get { return Record.ActionList.Select(x => x.ActionPartRecord); } } } ActionPart class public class ActionPart : ContentPart<ActionPartRecord> { public String Text { get { return Record.Text; } set { Record.Text = value; } } /*other field*/ } Migrations public int Create() { SchemaBuilder.CreateTable("ActionPartRecord", table => table .ContentPartRecord() .Column<string>("Text") .Column<double>("Price") .Column<int>("TextPosX") .Column<int>("TextPosY") .Column<string>("TextSale") .Column<int>("Color") ); ContentDefinitionManager.AlterPartDefinition("ActionPart", builder => builder .WithField("BaseImage", fieldBuilder => fieldBuilder.OfType("MediaPickerField").WithDisplayName("Action Image")) .WithField("PatternImage", fieldBuilder => fieldBuilder.OfType("MediaPickerField").WithDisplayName("Pattern Image")) .WithField("TimeExp", fieldBuilder => fieldBuilder.OfType("DateTimeField").WithDisplayName("Expecting date")) .Attachable()); ContentDefinitionManager.AlterTypeDefinition("Action", cfg => cfg .WithPart("CommonPart") .WithPart("TitlePart") .WithPart("RoutePart") .WithPart("BodyPart") .WithPart("ActionPart") .Creatable() .Indexed()); SchemaBuilder.CreateTable("ActionListRecord", table => table .Column<int>("Id", column => column.PrimaryKey().Identity()) .Column<int>("ActionPartRecord_Id") .Column<int>("ActionWidgetPartRecord_Id") ); SchemaBuilder.CreateTable("ActionWidgetPartRecord", table => table .ContentPartRecord() ); ContentDefinitionManager.AlterPartDefinition( "ActionWidgetPart", builder => builder.Attachable()); ContentDefinitionManager.AlterTypeDefinition("ActionWidget", cfg => cfg .WithPart("ActionWidgetPart") .WithPart("WidgetPart") .WithPart("CommonPart") .WithSetting("Stereotype", "Widget")); return 1; } Driver Display method protected override DriverResult Display( ActionWidgetPart part, string displayType, dynamic shapeHelper) { return ContentShape("Parts_ActionWidget", () => shapeHelper.Parts_ActionWidget( ContentPart: part, ActionList: part.ActionList)); } Widget View @foreach (var action in Model.ActionList) { <div class="item"> *How to access BaseImage Field in this row* <div class="sale-pattern"></div> <div class="container"> <div class="carousel-caption"> <h1>@action.Text</h1> <h1 class="price">@action.Price</h1> </div> </div> </div> }

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  • Overloading stream insertion without violating information hiding?

    - by Chris
    I'm using yaml-cpp for a project. I want to overload the << and >> operators for some classes, but I'm having an issue grappling with how to "properly" do this. Take the Note class, for example. It's fairly boring: class Note { public: // constructors Note( void ); ~Note( void ); // public accessor methods void number( const unsigned long& number ) { _number = number; } unsigned long number( void ) const { return _number; } void author( const unsigned long& author ) { _author = author; } unsigned long author( void ) const { return _author; } void subject( const std::string& subject ) { _subject = subject; } std::string subject( void ) const { return _subject; } void body( const std::string& body ) { _body = body; } std::string body( void ) const { return _body; } private: unsigned long _number; unsigned long _author; std::string _subject; std::string _body; }; The << operator is easy sauce. In the .h: YAML::Emitter& operator << ( YAML::Emitter& out, const Note& v ); And in the .cpp: YAML::Emitter& operator << ( YAML::Emitter& out, const Note& v ) { out << v.number() << v.author() << v.subject() << v.body(); return out; } No sweat. Then I go to declare the >> operator. In the .h: void operator >> ( const YAML::Node& node, Note& note ); But in the .cpp I get: void operator >> ( const YAML::Node& node, Note& note ) { node[0] >> ? node[1] >> ? node[2] >> ? node[3] >> ? return; } If I write things like node[0] >> v._number; then I would need to change the CV-qualifier to make all of the Note fields public (which defeats everything I was taught (by professors, books, and experience))) about data hiding. I feel like doing node[0] >> temp0; v.number( temp0 ); all over the place is not only tedious, error-prone, and ugly, but rather wasteful (what with the extra copies). Then I got wise: I attempted to move these two operators into the Note class itself, and declare them as friends, but the compiler (GCC 4.4) didn't like that: src/note.h:44: error: ‘YAML::Emitter& Note::operator<<(YAML::Emitter&, const Note&)’ must take exactly one argument src/note.h:45: error: ‘void Note::operator(const YAML::Node&, Note&)’ must take exactly one argument Question: How do I "properly" overload the >> operator for a class Without violating the information hiding principle? Without excessive copying?

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  • Using GA in GUI

    - by AlexT
    Sorry if this isn't clear as I'm writing this on a mobile device and I'm trying to make it quick. I've written a basic Genetic Algorithm with a binary encoding (genes) that builds a fitness value and evolves through several iterations using tournament selection, mutation and crossover. As a basic command-line example it seems to work. The problem I've got is with applying a genetic algorithm within a GUI as I am writing a maze-solving program that uses the GA to find a method through a maze. How do I turn my random binary encoded genes and fitness function (add all the binary values together) into a method to control a bot around a maze? I have built a basic GUI in Java consisting of a maze of labels (like a grid) with the available routes being in blue and the walls being in black. To reiterate my GA performs well and contains what any typical GA would (fitness method, get and set population, selection, crossover, etc) but now I need to plug it into a GUI to get my maze running. What needs to go where in order to get a bot that can move in different directions depending on what the GA says? Rough pseudocode would be great if possible As requested, an Individual is built using a separate class (Indiv), with all the main work being done in a Pop class. When a new individual is instantiated an array of ints represent the genes of said individual, with the genes being picked at random from a number between 0 and 1. The fitness function merely adds together the value of these genes and in the Pop class handles selection, mutation and crossover of two selected individuals. There's not much else to it, the command line program just shows evolution over n generations with the total fitness improving over each iteration. EDIT: It's starting to make a bit more sense now, although there are a few things that are bugging me... As Adamski has suggested I want to create an "Agent" with the options shown below. The problem I have is where the random bit string comes into play here. The agent knows where the walls are and has it laid out in a 4 bit string (i.e. 0111), but how does this affect the random 32 bit string? (i.e. 10001011011001001010011011010101) If I have the following maze (x is the start place, 2 is the goal, 1 is the wall): x 1 1 1 1 0 0 1 0 0 1 0 0 0 2 If I turn left I'm facing the wrong way and the agent will move completely off the maze if it moves forward. I assume that the first generation of the string will be completely random and it will evolve as the fitness grows but I don't get how the string will work within a maze. So, to get this straight... The fitness is the result of when the agent is able to move and is by a wall. The genes are a string of 32 bits, split into 16 sets of 2 bits to show the available actions and for the robot to move the two bits need to be passed with four bits from the agent showings its position near the walls. If the move is to go past a wall the move isn't made and it is deemed invalid and if the move is made and if a new wall is found then the fitness goes up. Is that right?

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  • ValidationProperty not returning entered value for textbox in custom ontrol

    - by nat
    hi I have a custom control, (relevant code at the bottom) it consists of some text/links and a hidden textbox (rather than a hidden input). when rendered, the user via another dialog and some JS sets the value of the textbox to an integer and clicks submit on the form. i am trying to assure that the user has entered a number (via the JS) and that the textbox is not still set to its default of "0" the requiredfieldvalidator works just fine, if i dont change the value it spots it on the client and fills the validation summary on the page with the appropriate message. unfortunately when i do fill the textbox, the validator also rejests the post as the controls textbox text value is still set to "0", even though on the form it has changed. clearly i am doing something wrong.. but cant work out what it is? could someone enlighten me please, this is driving me potty if i step through the code, when the get of the mediaidtext is hit,the findcontrol finds does not the textbox, if i inspect the controls collection however i can find the textbox, but its value is still "0" it also seems that when findcontrol is called, the createchildcontrols is called again - thus resetting the value back to "0" there.. ! how can i ever assure the control realises that the textbox value has changed? many thanks code below nat [ValidationProperty("MediaIdText")] public class MediaLibraryFileControl: CompositeControl { private int mediaId = 0; public int MediaId { get { return mediaId; } set { mediaId = value; } } public string MediaIdText { get { string txt = "0"; Control ctrl = this.FindControl(this.UniqueID+ "_hidden"); try { txt = ((TextBox)ctrl).Text; MediaId = Convert.ToInt32(txt); } catch { MediaId = 0; } return txt; } } protected override void CreateChildControls() { this.Controls.Add(new LiteralControl("<span>")); this.Controls.Add(new LiteralControl("<span id=\"" + TextControlName + "\">" + getMediaDetails() + "</span>")); TextBox tb = new TextBox(); tb.Text = this.MediaId.ToString(); tb.ID = this.UniqueID + "_hidden"; tb.CssClass = "hidden"; this.Controls.Add(tb); if (Select == true) { this.Controls.Add(new LiteralControl(string.Format("&nbsp;[<a href=\"javascript:{0}(this,'{1}','{2}')\" class=\"select\">{3}</a>]", dialog, this.UniqueID, this.categoryId, "select"))); this.Controls.Add(new LiteralControl(string.Format("&nbsp;[<a href=\"javascript:{0}(this,'{1}')\" class=\"select\">{2}</a>]", clearDialog, this.ID, "clear"))); } this.Controls.Add(new LiteralControl("</span>")); } protected virtual string getMediaDetails() { //... return String.Empty; } } this is the code adding the validationcontrol the editcontrol is the instance of the control above public override Control RenderValidationControl(Control editControl) { Control ctrl = new PlaceHolder(); RequiredFieldValidator req = new RequiredFieldValidator(); req.ID = editControl.ClientID + "_validator"; req.ControlToValidate = editControl.ID; req.Display = ValidatorDisplay.None; req.InitialValue = "0"; req.EnableClientScript = false; req.ErrorMessage = "control cannot be blank"; ctrl.Controls.Add(req); return ctrl; }

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  • Unable to write data to the transport connection: An existing connection was forcibly closed by the remote host

    - by xnoor
    i have an update server that sends client updates through TCP port 12000, the sending of a single file is successful only the first time, but after that i get an error message on the server "Unable to write data to the transport connection: An existing connection was forcibly closed by the remote host", if i restart the update service on the server, it works again only one, i have normal multithreaded windows service SERVER CODE namespace WSTSAU { public partial class ApplicationUpdater : ServiceBase { private Logger logger = LogManager.GetCurrentClassLogger(); private int _listeningPort; private int _ApplicationReceivingPort; private string _setupFilename; private string _startupPath; public ApplicationUpdater() { InitializeComponent(); } protected override void OnStart(string[] args) { init(); logger.Info("after init"); Thread ListnerThread = new Thread(new ThreadStart(StartListener)); ListnerThread.IsBackground = true; ListnerThread.Start(); logger.Info("after thread start"); } private void init() { _listeningPort = Convert.ToInt16(ConfigurationSettings.AppSettings["ListeningPort"]); _setupFilename = ConfigurationSettings.AppSettings["SetupFilename"]; _startupPath = System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase).Substring(6); } private void StartListener() { try { logger.Info("Listening Started"); ThreadPool.SetMinThreads(50, 50); TcpListener listener = new TcpListener(_listeningPort); listener.Start(); while (true) { TcpClient c = listener.AcceptTcpClient(); ThreadPool.QueueUserWorkItem(ProcessReceivedMessage, c); } } catch (Exception ex) { logger.Error(ex.Message); } } void ProcessReceivedMessage(object c) { try { TcpClient tcpClient = c as TcpClient; NetworkStream Networkstream = tcpClient.GetStream(); byte[] _data = new byte[1024]; int _bytesRead = 0; _bytesRead = Networkstream.Read(_data, 0, _data.Length); MessageContainer messageContainer = new MessageContainer(); messageContainer = SerializationManager.XmlFormatterByteArrayToObject(_data, messageContainer) as MessageContainer; switch (messageContainer.messageType) { case MessageType.ApplicationUpdateMessage: ApplicationUpdateMessage appUpdateMessage = new ApplicationUpdateMessage(); appUpdateMessage = SerializationManager.XmlFormatterByteArrayToObject(messageContainer.messageContnet, appUpdateMessage) as ApplicationUpdateMessage; Func<ApplicationUpdateMessage, bool> HandleUpdateRequestMethod = HandleUpdateRequest; IAsyncResult cookie = HandleUpdateRequestMethod.BeginInvoke(appUpdateMessage, null, null); bool WorkerThread = HandleUpdateRequestMethod.EndInvoke(cookie); break; } } catch (Exception ex) { logger.Error(ex.Message); } } private bool HandleUpdateRequest(ApplicationUpdateMessage appUpdateMessage) { try { TcpClient tcpClient = new TcpClient(); NetworkStream networkStream; FileStream fileStream = null; tcpClient.Connect(appUpdateMessage.receiverIpAddress, appUpdateMessage.receiverPortNumber); networkStream = tcpClient.GetStream(); fileStream = new FileStream(_startupPath + "\\" + _setupFilename, FileMode.Open, FileAccess.Read); FileInfo fi = new FileInfo(_startupPath + "\\" + _setupFilename); BinaryReader binFile = new BinaryReader(fileStream); FileUpdateMessage fileUpdateMessage = new FileUpdateMessage(); fileUpdateMessage.fileName = fi.Name; fileUpdateMessage.fileSize = fi.Length; MessageContainer messageContainer = new MessageContainer(); messageContainer.messageType = MessageType.FileProperties; messageContainer.messageContnet = SerializationManager.XmlFormatterObjectToByteArray(fileUpdateMessage); byte[] messageByte = SerializationManager.XmlFormatterObjectToByteArray(messageContainer); networkStream.Write(messageByte, 0, messageByte.Length); int bytesSize = 0; byte[] downBuffer = new byte[2048]; while ((bytesSize = fileStream.Read(downBuffer, 0, downBuffer.Length)) > 0) { networkStream.Write(downBuffer, 0, bytesSize); } fileStream.Close(); tcpClient.Close(); networkStream.Close(); return true; } catch (Exception ex) { logger.Info(ex.Message); return false; } finally { } } protected override void OnStop() { } } i have to note something that my windows service (server) is multithreaded.. i hope anyone can help with this

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  • System.Threading.Timer Doesn't Trigger my TimerCallBack Delegate

    - by Tom Kong
    Hi, I am writing my first Windows Service using C# and I am having some trouble with my Timer class. When the service is started, it runs as expected but the code will not execute again (I want it to run every minute) Please take a quick look at the attached source and let me know if you see any obvious mistakes! TIA using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Diagnostics; using System.Linq; using System.ServiceProcess; using System.Text; using System.Threading; using System.IO; namespace CXO001 { public partial class Service1 : ServiceBase { public Service1() { InitializeComponent(); } /* * Aim: To calculate and update the Occupancy values for the different Sites * * Method: Retrieve data every minute, updating a public value which can be polled */ protected override void OnStart(string[] args) { Daemon(); } public void Daemon() { TimerCallback tcb = new TimerCallback(On_Tick); TimeSpan duetime = new TimeSpan(0, 0, 1); TimeSpan interval = new TimeSpan(0, 1, 0); Timer querytimer = new Timer(tcb, null, duetime, interval); } protected override void OnStop() { } static int[] floorplanids = new int[] { 115, 114, 107, 108 }; public static List<Record> Records = new List<Record>(); static bool firstrun = true; public static void On_Tick(object timercallback) { //Update occupancy data for the last minute //Save a copy of the public values to HDD with a timestamp string starttime; if (Records.Count > 0) { starttime = Records.Last().TS; firstrun = false; } else { starttime = DateTime.Today.AddHours(7).ToString(); firstrun = true; } DateTime endtime = DateTime.Now; GetData(starttime, endtime); } public static void GetData(string starttime, DateTime endtime) { string connstr = "Data Source = 192.168.1.123; Initial Catalog = Brickstream_OPS; User Id = Brickstream; Password = bstas;"; DataSet resultds = new DataSet(); //Get the occupancy for each Zone foreach (int zone in floorplanids) { SQL s = new SQL(); string querystr = "SELECT SUM(DIRECTIONAL_METRIC.NUM_TO_ENTER - DIRECTIONAL_METRIC.NUM_TO_EXIT) AS 'Occupancy' FROM REPORT_OBJECT INNER JOIN REPORT_OBJ_METRIC ON REPORT_OBJECT.REPORT_OBJ_ID = REPORT_OBJ_METRIC.REPORT_OBJECT_ID INNER JOIN DIRECTIONAL_METRIC ON REPORT_OBJ_METRIC.REP_OBJ_METRIC_ID = DIRECTIONAL_METRIC.REP_OBJ_METRIC_ID WHERE (REPORT_OBJ_METRIC.M_START_TIME BETWEEN '" + starttime + "' AND '" + endtime.ToString() + "') AND (REPORT_OBJECT.FLOORPLAN_ID = '" + zone + "');"; resultds = s.Go(querystr, connstr, zone.ToString(), resultds); } List<Record> result = new List<Record>(); int c = 0; foreach (DataTable dt in resultds.Tables) { Record r = new Record(); r.TS = DateTime.Now.ToString(); r.Zone = dt.TableName; if (!firstrun) { r.Occupancy = (dt.Rows[0].Field<int>("Occupancy")) + (Records[c].Occupancy); } else { r.Occupancy = dt.Rows[0].Field<int>("Occupancy"); } result.Add(r); c++; } Records = result; MrWriter(); } public static void MrWriter() { StringBuilder output = new StringBuilder("Time,Zone,Occupancy\n"); foreach (Record r in Records) { output.Append(r.TS); output.Append(","); output.Append(r.Zone); output.Append(","); output.Append(r.Occupancy.ToString()); output.Append("\n"); } output.Append(firstrun.ToString()); output.Append(DateTime.Now.ToFileTime()); string filePath = @"C:\temp\CXO.csv"; File.WriteAllText(filePath, output.ToString()); } } }

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  • Java: How to check the random letters from a-z, out of 10 letters minimum 2 letter should be a vowel

    - by kalandar
    I am writing a program to validate the following scenarios: Scenario 1: I am using the Random class from java.util. The random class will generate 10 letters from a-z and within 10 letter, minimum 2 letters must be a vowels. Scenario 2: When the player 1 and player 2 form a word from A-Z, he will score some points. There will be a score for each letter. I have already assigned the values for A-Z. At the end of the game, the system should display a scores for player 1 and player 2. How do i do it? Please help. I will post my code here. Thanks a lot. =========================================== import java.util.Random; import java.util.Scanner; public class FindYourWords { public static void main(String[] args) { Random rand = new Random(); Scanner userInput = new Scanner(System.in); //==================Player object=============================================== Player playerOne = new Player(); playerOne.wordScore = 0; playerOne.choice = "blah"; playerOne.turn = true; Player playerTwo = new Player(); playerTwo.wordScore = 0; playerTwo.choice = "blah"; playerTwo.turn = false; //================== Alphabet ================================================== String[] newChars = { "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z" }; //values of the 26 alphabets to be used int [] letterScore = {1,3,3,2,1,4,2,4,1,8,5,1,3,1,1,3,10,1,1,1,1,4,4,8,4,10}; // to assign score to the player1 and player 2 String[] vowel = { "a", "e", "i", "o", "u" }; // values for vowels int vow=0; System.out.println("FINDYOURWORDS\n"); int[] arrayRandom = new int[10]; //int array for word limiter String[] randomLetter = new String[10]; //storing the letters in newChars into this array //=============================================================================== boolean cont = true; while (cont) { if (playerOne.turn) { System.out.print("Letters of Player 1: "); } else if (!playerOne.turn) { System.out.print("Letters of Player 2: "); } for (int i = 0; i < arrayRandom.length; i++) { //running through the array limiter int r = rand.nextInt(newChars.length); //assigning random nums to the array of letters randomLetter[i] = newChars[r]; System.out.print(randomLetter[i]+ " "); } //input section for player System.out.println(""); System.out.println("Enter your word (or '@' to pass or '!' to quit): "); if (playerOne.turn) { playerOne.choice = userInput.next(); System.out.println(playerOne.turn); playerOne.turn = false; } else if (!playerOne.turn){ playerTwo.choice = userInput.next(); System.out.println(playerOne.turn); playerOne.turn = true; } //System.out.println(choice); String[] wordList = FileUtil.readDictFromFile("words.txt"); //Still dunno what this is for if (playerOne.choice.equals("@")) { playerOne.turn = false; } else if (playerTwo.choice.equals("@")) { playerOne.turn = true; } else if (playerOne.choice.equals("!")) { cont = false; } for (int i = 0; i < wordList.length; i++) { //System.out.println(wordList[i]); if (playerOne.choice.equalsIgnoreCase(wordList[i]) || playerTwo.choice.equalsIgnoreCase(wordList[i])){ } } } }}

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  • File observer problem

    - by Nemat
    Hi, I want to listen to the changes occured in file system.I am using FileObserver.Here is my code: Code: class MyDirObserver extends FileObserver { String superPath; public MyDirObserver(String path) { super(path, ALL_EVENTS); this.superPath=path; } public void onEvent(int event, String path) { Log.e("onEvent of Directory", "=== onEvent ==="); try{ _Dump("dir", event, path,superPath); } catch(NullPointerException ex) { Log.e("ERROR","I am getting error"); } } } private void _Dump(final String tag, int event, String path,String superPath) { Log.d(tag, "=== dump begin ==="); Log.d(tag, "path=" + path); Log.d(tag,"super path="+superPath); Log.d(tag, "event list:"); if ((event & FileObserver.OPEN) != 0) { Log.d(tag, " OPEN"); } if ((event & FileObserver.CLOSE_NOWRITE) != 0) { Log.d(tag, " CLOSE_NOWRITE"); } if ((event & FileObserver.CLOSE_WRITE) != 0) { Log.d(tag, " CLOSE_WRITE"); Log.i("NEWFILEOBSERVER","File is Modified"); if(path!=null) { Log.d("---------FilePath",superPath+path); } } if ((event & FileObserver.CREATE) != 0) { isCreate=true; Log.i("NEWFILEOBSERVER","File is Created "); if(path!=null) { Log.d("---------FilePath",superPath+path); } Log.d(tag, " CREATE"); } if ((event & FileObserver.DELETE) != 0) { Log.i("NEWFILEOBSERVER","File is deleted"); if(path!=null) { Log.d("---------FilePath",superPath+path); } // startMyActivity("A new file is deleted thats="+superPath); Log.d(tag, " DELETE"); } if ((event & FileObserver.DELETE_SELF) != 0) { Log.d(tag, " DELETE_SELF"); } if ((event & FileObserver.ACCESS) != 0) { Log.d(tag, " ACCESS"); } if ((event & FileObserver.MODIFY) != 0) { if(!isModified) isModified=true; if(isModified && isOpen) isAgainModified=true; Log.d(tag, " MODIFY"); } if ((event & FileObserver.MOVED_FROM) != 0) { Log.d(tag, " MOVED_FROM"); if(path!=null) { Log.d("---------FilePath",superPath+path); } } if ((event & FileObserver.MOVED_TO) != 0) { Log.d(tag, " MOVED_TO"); if(path!=null) { Log.d("---------FilePath",superPath+path); } } if ((event & FileObserver.MOVE_SELF) != 0) { Log.d(tag, " MOVE_SELF"); } if ((event & FileObserver.ATTRIB) != 0) { Log.d(tag, " ATTRIB"); } Log.d(tag, "=== dump end ==="); } it stops after some time.I dont get the exact time but doesnt work always though I call startWatching() in service in a loop which runs for all the folders of sdcard and calls startWatching() for each of them. It shows unpredictable behaviour and stops listening for some folders and runs perfectly for the others. I hope you guys help me.I tried many ways but it doesnt work perfectly.Am I doing something wrong??? or there we have some other way to do this....... Please help me........I have to get this done withing few days...... Any help is appreciated!!!! Thanks in Advance Nemat

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  • How to generalize a method call in Java (to avoid code duplication)

    - by dln385
    I have a process that needs to call a method and return its value. However, there are several different methods that this process may need to call, depending on the situation. If I could pass the method and its arguments to the process (like in Python), then this would be no problem. However, I don't know of any way to do this in Java. Here's a concrete example. (This example uses Apache ZooKeeper, but you don't need to know anything about ZooKeeper to understand the example.) The ZooKeeper object has several methods that will fail if the network goes down. In this case, I always want to retry the method. To make this easy, I made a "BetterZooKeeper" class that inherits the ZooKeeper class, and all of its methods automatically retry on failure. This is what the code looked like: public class BetterZooKeeper extends ZooKeeper { private void waitForReconnect() { // logic } @Override public Stat exists(String path, Watcher watcher) { while (true) { try { return super.exists(path, watcher); } catch (KeeperException e) { // We will retry. } waitForReconnect(); } } @Override public byte[] getData(String path, boolean watch, Stat stat) { while (true) { try { return super.getData(path, watch, stat); } catch (KeeperException e) { // We will retry. } waitForReconnect(); } } @Override public void delete(String path, int version) { while (true) { try { super.delete(path, version); return; } catch (KeeperException e) { // We will retry. } waitForReconnect(); } } } (In the actual program there is much more logic and many more methods that I took out of the example for simplicity.) We can see that I'm using the same retry logic, but the arguments, method call, and return type are all different for each of the methods. Here's what I did to eliminate the duplication of code: public class BetterZooKeeper extends ZooKeeper { private void waitForReconnect() { // logic } @Override public Stat exists(final String path, final Watcher watcher) { return new RetryableZooKeeperAction<Stat>() { @Override public Stat action() { return BetterZooKeeper.super.exists(path, watcher); } }.run(); } @Override public byte[] getData(final String path, final boolean watch, final Stat stat) { return new RetryableZooKeeperAction<byte[]>() { @Override public byte[] action() { return BetterZooKeeper.super.getData(path, watch, stat); } }.run(); } @Override public void delete(final String path, final int version) { new RetryableZooKeeperAction<Object>() { @Override public Object action() { BetterZooKeeper.super.delete(path, version); return null; } }.run(); return; } private abstract class RetryableZooKeeperAction<T> { public abstract T action(); public final T run() { while (true) { try { return action(); } catch (KeeperException e) { // We will retry. } waitForReconnect(); } } } } The RetryableZooKeeperAction is parameterized with the return type of the function. The run() method holds the retry logic, and the action() method is a placeholder for whichever ZooKeeper method needs to be run. Each of the public methods of BetterZooKeeper instantiates an anonymous inner class that is a subclass of the RetryableZooKeeperAction inner class, and it overrides the action() method. The local variables are (strangely enough) implicitly passed to the action() method, which is possible because they are final. In the end, this approach does work and it does eliminate the duplication of the retry logic. However, it has two major drawbacks: (1) it creates a new object every time a method is called, and (2) it's ugly and hardly readable. Also I had to workaround the 'delete' method which has a void return value. So, here is my question: is there a better way to do this in Java? This can't be a totally uncommon task, and other languages (like Python) make it easier by allowing methods to be passed. I suspect there might be a way to do this through reflection, but I haven't been able to wrap my head around it.

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  • The type or namespace cannot be found (are you missing a using directive or an assembly reference?)

    - by Kumu
    I get the following error when I try to compile my C# program: The type or namespace name 'Login' could not be found (are you missing a using directive or an assembly reference?) using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; namespace FootballLeague { public partial class MainMenu : Form { FootballLeagueDatabase footballLeagueDatabase; Game game; Team team; Login login; //Error here public MainMenu() { InitializeComponent(); changePanel(1); } public MainMenu(FootballLeagueDatabase footballLeagueDatabaseIn) { InitializeComponent(); footballLeagueDatabase = footballLeagueDatabaseIn; } private void Form_Loaded(object sender, EventArgs e) { } private void gameButton_Click(object sender, EventArgs e) { int option = 0; changePanel(option); } private void scoreboardButton_Click(object sender, EventArgs e) { int option = 1; changePanel(option); } private void changePanel(int optionIn) { gamePanel.Hide(); scoreboardPanel.Hide(); string title = "Football League System"; switch (optionIn) { case 0: gamePanel.Show(); this.Text = title + " - Game Menu"; break; case 1: scoreboardPanel.Show(); this.Text = title + " - Display Menu"; break; } } private void logoutButton_Click(object sender, EventArgs e) { login = new Login(); login.Show(); this.Hide(); } Login.cs class: using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; namespace FootballLeagueSystem { public partial class Login : Form { MainMenu menu; public Login() { InitializeComponent(); } private void administratorLoginButton_Click(object sender, EventArgs e) { string username1 = "08247739"; string password1 = "08247739"; if ((userNameTxt.Text.Length) == 0) MessageBox.Show("Please enter your username!"); else if ((passwordTxt.Text.Length) == 0) MessageBox.Show("Please enter your password!"); else if (userNameTxt.Text.Equals("") || passwordTxt.Text.Equals("")) MessageBox.Show("Invalid Username or Password!"); else { if (this.userNameTxt.Text == username1 && this.passwordTxt.Text == password1) MessageBox.Show("Welcome Administrator!", "Administrator Login"); menu = new MainMenu(); menu.Show(); this.Hide(); } } private void managerLoginButton_Click(object sender, EventArgs e) { { string username2 = "1111"; string password2 = "1111"; if ((userNameTxt.Text.Length) == 0) MessageBox.Show("Please enter your username!"); else if ((passwordTxt.Text.Length) == 0) MessageBox.Show("Please enter your password!"); else if (userNameTxt.Text.Equals("") && passwordTxt.Text.Equals("")) MessageBox.Show("Invalid Username or Password!"); else { if (this.userNameTxt.Text == username2 && this.passwordTxt.Text == password2) MessageBox.Show("Welcome Manager!", "Manager Login"); menu = new MainMenu(); menu.Show(); this.Hide(); } } } private void cancelButton_Click(object sender, EventArgs e) { this.Close(); } } } Where is the error? What am I doing wrong?

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  • Undefined reference to vtable

    - by RyanG
    So, I'm getting the infamously horrible "undefined reference to 'vtable..." error for the following code (The class in question is CGameModule.) and I cannot for the life of me understand what the problem is. At first, I thought it was related to forgetting to give a virtual function a body, but as far as I understand, everything is all here. The inheritance chain is a little long, but here is the related source code. I'm not sure what other information I should provide. My code: class CGameModule : public CDasherModule { public: CGameModule(Dasher::CEventHandler *pEventHandler, CSettingsStore *pSettingsStore, CDasherInterfaceBase *pInterface, ModuleID_t iID, const char *szName) : CDasherModule(pEventHandler, pSettingsStore, iID, 0, szName) { g_pLogger->Log("Inside game module constructor"); m_pInterface = pInterface; } virtual ~CGameModule() {}; std::string GetTypedTarget(); std::string GetUntypedTarget(); bool DecorateView(CDasherView *pView) { //g_pLogger->Log("Decorating the view"); return false; } void SetDasherModel(CDasherModel *pModel) { m_pModel = pModel; } virtual void HandleEvent(Dasher::CEvent *pEvent); private: CDasherNode *pLastTypedNode; CDasherNode *pNextTargetNode; std::string m_sTargetString; size_t m_stCurrentStringPos; CDasherModel *m_pModel; CDasherInterfaceBase *m_pInterface; }; } Inherits from... class CDasherModule; typedef std::vector<CDasherModule*>::size_type ModuleID_t; /// \ingroup Core /// @{ class CDasherModule : public Dasher::CDasherComponent { public: CDasherModule(Dasher::CEventHandler * pEventHandler, CSettingsStore * pSettingsStore, ModuleID_t iID, int iType, const char *szName); virtual ModuleID_t GetID(); virtual void SetID(ModuleID_t); virtual int GetType(); virtual const char *GetName(); virtual bool GetSettings(SModuleSettings **pSettings, int *iCount) { return false; }; private: ModuleID_t m_iID; int m_iType; const char *m_szName; }; Which inherits from.... namespace Dasher { class CEvent; class CEventHandler; class CDasherComponent; }; /// \ingroup Core /// @{ class Dasher::CDasherComponent { public: CDasherComponent(Dasher::CEventHandler* pEventHandler, CSettingsStore* pSettingsStore); virtual ~CDasherComponent(); void InsertEvent(Dasher::CEvent * pEvent); virtual void HandleEvent(Dasher::CEvent * pEvent) {}; bool GetBoolParameter(int iParameter) const; void SetBoolParameter(int iParameter, bool bValue) const; long GetLongParameter(int iParameter) const; void SetLongParameter(int iParameter, long lValue) const; std::string GetStringParameter(int iParameter) const; void SetStringParameter(int iParameter, const std::string & sValue) const; ParameterType GetParameterType(int iParameter) const; std::string GetParameterName(int iParameter) const; protected: Dasher::CEventHandler *m_pEventHandler; CSettingsStore *m_pSettingsStore; }; /// @} #endif

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  • Create and Share a File (Also a mysterious error)

    - by Kirk
    My goal is to create a XML file and then send it through the share Intent. I'm able to create a XML file using this code FileOutputStream outputStream = context.openFileOutput(fileName, Context.MODE_WORLD_READABLE); PrintStream printStream = new PrintStream(outputStream); String xml = this.writeXml(); // get XML here printStream.println(xml); printStream.close(); I'm stuck trying to retrieve a Uri to the output file in order to share it. I first tried to access the file by converting the file to a Uri File outFile = context.getFileStreamPath(fileName); return Uri.fromFile(outFile); This returns file:///data/data/com.my.package/files/myfile.xml but I cannot appear to attach this to an email, upload, etc. If I manually check the file length, it's proper and shows there is a reasonable file size. Next I created a content provider and tried to reference the file and it isn't a valid handle to the file. The ContentProvider doesn't ever seem to be called a any point. Uri uri = Uri.parse("content://" + CachedFileProvider.AUTHORITY + "/" + fileName); return uri; This returns content://com.my.package.provider/myfile.xml but I check the file and it's zero length. How do I access files properly? Do I need to create the file with the content provider? If so, how? Update Here is the code I'm using to share. If I select Gmail, it does show as an attachment but when I send it gives an error Couldn't show attachment and the email that arrives has no attachment. public void onClick(View view) { Log.d(TAG, "onClick " + view.getId()); switch (view.getId()) { case R.id.share_cancel: setResult(RESULT_CANCELED, getIntent()); finish(); break; case R.id.share_share: MyXml xml = new MyXml(); Uri uri; try { uri = xml.writeXmlToFile(getApplicationContext(), "myfile.xml"); //uri is "file:///data/data/com.my.package/files/myfile.xml" Log.d(TAG, "Share URI: " + uri.toString() + " path: " + uri.getPath()); File f = new File(uri.getPath()); Log.d(TAG, "File length: " + f.length()); // shows a valid file size Intent shareIntent = new Intent(); shareIntent.setAction(Intent.ACTION_SEND); shareIntent.putExtra(Intent.EXTRA_STREAM, uri); shareIntent.setType("text/plain"); startActivity(Intent.createChooser(shareIntent, "Share")); } catch (FileNotFoundException e) { e.printStackTrace(); } break; } } I noticed that there is an Exception thrown here from inside createChooser(...), but I can't figure out why it's thrown. E/ActivityThread(572): Activity com.android.internal.app.ChooserActivity has leaked IntentReceiver com.android.internal.app.ResolverActivity$1@4148d658 that was originally registered here. Are you missing a call to unregisterReceiver()? I've researched this error and can't find anything obvious. Both of these links suggest that I need to unregister a receiver. Chooser Activity Leak - Android Why does Intent.createChooser() need a BroadcastReceiver and how to implement? I have a receiver setup, but it's for an AlarmManager that is set elsewhere and doesn't require the app to register / unregister. Code for openFile(...) In case it's needed, here is the content provider I've created. public ParcelFileDescriptor openFile(Uri uri, String mode) throws FileNotFoundException { String fileLocation = getContext().getCacheDir() + "/" + uri.getLastPathSegment(); ParcelFileDescriptor pfd = ParcelFileDescriptor.open(new File(fileLocation), ParcelFileDescriptor.MODE_READ_ONLY); return pfd; }

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  • Why is my NSURLConnection so slow?

    - by Bama91
    I have setup an NSURLConnection using the guidelines in Using NSURLConnection from the Mac OS X Reference Library, creating an NSMutableURLRequest as POST to a PHP script with a custom body to upload 20 MB of data (see code below). Note that the post body is what it is (line breaks and all) to exactly match an existing desktop implementation. When I run this in the iPhone simulator, the post is successful, but takes an order of magnitude longer than if I run the equivalent code locally on my Mac in C++ (20 minutes vs. 20 seconds, respectively). Any ideas why the difference is so dramatic? I understand that the simulator will give different results than the actual device, but I would expect at least similar results. Thanks const NSUInteger kDataSizePOST = 20971520; const NSString* kServerBDC = @"WWW.SOMEURL.COM"; const NSString* kUploadURL = @"http://WWW.SOMEURL.COM/php/test/upload.php"; const NSString* kUploadFilename = @"test.data"; const NSString* kUsername = @"testuser"; const NSString* kHostname = @"testhost"; srandom(time(NULL)); NSMutableData *uniqueData = [[NSMutableData alloc] initWithCapacity:kDataSizePOST]; for (unsigned int i = 0 ; i < kDataSizePOST ; ++i) { u_int32_t randomByte = ((random() % 95) + 32); [uniqueData appendBytes:(void*)&randomByte length:1]; } NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init]; [request setURL:[NSURL URLWithString:kUploadURL]]; [request setHTTPMethod:@"POST"]; NSString *boundary = @"aBcDd"; NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; boundary=%@",boundary]; [request addValue:contentType forHTTPHeaderField: @"Content-Type"]; NSMutableData *postbody = [NSMutableData data]; [postbody appendData:[[NSString stringWithFormat:@"--%@\nContent-Size:%d",boundary,[uniqueData length]] dataUsingEncoding:NSUTF8StringEncoding]]; [postbody appendData:[[NSString stringWithFormat:@"\nContent-Disposition: form-data; name=test; filename=%@", kUploadFilename] dataUsingEncoding:NSUTF8StringEncoding]]; [postbody appendData:[[NSString stringWithString:@";\nContent-Type: multipart/mixed;\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]]; [postbody appendData:[NSData dataWithData:uniqueData]]; [postbody appendData:[[NSString stringWithFormat:@"--%@\nContent-Size:%d",boundary,[kUsername length]] dataUsingEncoding:NSUTF8StringEncoding]]; [postbody appendData:[[NSString stringWithFormat:@"\nContent-Disposition: inline; name=Username;\n\r\n%@",kUsername] dataUsingEncoding:NSUTF8StringEncoding]]; [postbody appendData:[[NSString stringWithFormat:@"--%@\nContent-Size:%d",boundary,[kHostname length]] dataUsingEncoding:NSUTF8StringEncoding]]; [postbody appendData:[[NSString stringWithFormat:@"\nContent-Disposition: inline; name=Hostname;\n\r\n%@",kHostname] dataUsingEncoding:NSUTF8StringEncoding]]; [postbody appendData:[[NSString stringWithFormat:@"\n--%@--",boundary] dataUsingEncoding:NSUTF8StringEncoding]]; [request setHTTPBody:postbody]; NSURLConnection *theConnection = [[NSURLConnection alloc] initWithRequest:request delegate:self]; if (theConnection) { _receivedData = [[NSMutableData data] retain]; } else { // Inform the user that the connection failed. } [request release]; [uniqueData release];

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  • Servlet response wrapper has encoding problem

    - by John O
    A servlet response wrapper is being used in a Servlet Filter. The idea is that the response is manipulated, with a 'nonce' value being injected into forms, as part of defence against CSRF attacks. The web app is using UTF-8 everywhere. When the Servlet Filter is absent, no problems. When the filter is added, encoding issues occur. (It seems as if the response is reverting to 8859-1.) The guts of the code : final class CsrfResponseWrapper extends AbstractResponseWrapper { ... byte[] modifyResponse(byte[] aInputResponse){ ... String originalInput = new String(aInputResponse, encoding); String modifiedResult = addHiddenParamToPostedForms(originalInput); result = modifiedResult.getBytes(encoding); ... } ... } As I understand it, the transition between byte-land and String-land should specify an encoding. That is done here, as you can see, in two places. The value of the 'encoding' variable is 'UTF-8'; the alteration of the String itself is standard string manipulation (with a regex), and never specifies an encoding (addHiddenParamToPostedForms). Where am I in error about the encoding? EDIT: Here is the base class (sorry it's rather long): package hirondelle.web4j.security; import javax.servlet.ServletOutputStream; import javax.servlet.ServletResponse; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpServletResponseWrapper; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.PrintWriter; /** Abstract Base Class for altering response content. (May be useful in future contexts as well. For now, keep package-private.) */ abstract class AbstractResponseWrapper extends HttpServletResponseWrapper { AbstractResponseWrapper(ServletResponse aServletResponse) throws IOException { super((HttpServletResponse)aServletResponse); fOutputStream = new ModifiedOutputStream(aServletResponse.getOutputStream()); fWriter = new PrintWriter(fOutputStream); } /** Return the modified response. */ abstract byte[] modifyResponse(byte[] aInputResponse); /** Standard servlet method. */ public final ServletOutputStream getOutputStream() { //fLogger.fine("Modified Response : Getting output stream."); if ( fWriterReturned ) { throw new IllegalStateException(); } fOutputStreamReturned = true; return fOutputStream; } /** Standard servlet method. */ public final PrintWriter getWriter() { //fLogger.fine("Modified Response : Getting writer."); if ( fOutputStreamReturned ) { throw new IllegalStateException(); } fWriterReturned = true; return fWriter; } // PRIVATE /* Well-behaved servlets return either an OutputStream or a PrintWriter, but not both. */ private PrintWriter fWriter; private ModifiedOutputStream fOutputStream; /* These items are used to implement conformance to the javadoc for ServletResponse, regarding exceptions being thrown. */ private boolean fWriterReturned; private boolean fOutputStreamReturned; /** Modified low level output stream. */ private class ModifiedOutputStream extends ServletOutputStream { public ModifiedOutputStream(ServletOutputStream aOutputStream) { fServletOutputStream = aOutputStream; fBuffer = new ByteArrayOutputStream(); } /** Must be implemented to make this class concrete. */ public void write(int aByte) { fBuffer.write(aByte); } public void close() throws IOException { if ( !fIsClosed ){ processStream(); fServletOutputStream.close(); fIsClosed = true; } } public void flush() throws IOException { if ( fBuffer.size() != 0 ){ if ( !fIsClosed ) { processStream(); fBuffer = new ByteArrayOutputStream(); } } } /** Perform the core processing, by calling the abstract method. */ public void processStream() throws IOException { fServletOutputStream.write(modifyResponse(fBuffer.toByteArray())); fServletOutputStream.flush(); } // PRIVATE // private ServletOutputStream fServletOutputStream; private ByteArrayOutputStream fBuffer; /** Tracks if this stream has been closed. */ private boolean fIsClosed = false; } }

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  • move carat to the end of a text input field AND make the end visible

    - by user322384
    I'm going insane. I have an autosuggest box where users choose a suggestion. On the next suggestion selection the value of the text input box exceeds its size. I can move the carat to the end of the input field crossbrowser, no problem. But on Chrome and Safari I cannot SEE the carat at the end. The end of the text is not visible. Is there a way to move the carat to the end of a text input field AND have the end of the field visible so that the user is not confused about where the input carat went? what I got so far: <html> <head><title>Field update test</title></head> <body> <form action="#" method="POST" name="testform"> <p>After a field is updated the carat should be at the end of the text field AND the end of the text should be visible</p> <input type="text" name="testbox" value="" size="40"> <p><a href="javascript:void(0);" onclick="add_more_text();">add more text</a></p> </form> <script type="text/javascript"> <!-- var count = 0; function add_more_text() { var textfield = document.testform.elements['testbox']; textfield.blur(); textfield.focus(); if (count == 0) textfield.value = ''; // clear old count++; textfield.value = (count ? textfield.value : '') + ", " + count + ": This is some sample text"; // move to the carat to the end of the field if (textfield.setSelectionRange) { textfield.setSelectionRange(textfield.value.length, textfield.value.length); } else if (textfield.createTextRange) { var range = textfield.createTextRange(); range.collapse(true); range.moveEnd('character', textfield.value.length); range.moveStart('character', textfield.value.length); range.select(); } // force carat visibility for some browsers if (document.createEvent) { // Trigger a space keypress. var e = document.createEvent('KeyboardEvent'); if (typeof(e.initKeyEvent) != 'undefined') { e.initKeyEvent('keypress', true, true, null, false, false, false, false, 0, 32); } else { e.initKeyboardEvent('keypress', true, true, null, false, false, false, false, 0, 32); } textfield.dispatchEvent(e); // Trigger a backspace keypress. e = document.createEvent('KeyboardEvent'); if (typeof(e.initKeyEvent) != 'undefined') { e.initKeyEvent('keypress', true, true, null, false, false, false, false, 8, 0); } else { e.initKeyboardEvent('keypress', true, true, null, false, false, false, false, 8, 0); } textfield.dispatchEvent(e); } } // --> </script> </body> </html> Thanks

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  • jsp error plz check this code why are not insert my data into database

    - by lekhni
    <%@ page language="java" import="java.util.*" pageEncoding="ISO-8859-1"%> <%@ page import="java.sql.*" %> <%@ page import="java.io.*"%> <%@ page import="java.io.File"%> <%@ page import="java.util.*"%> <%@ page import="java.sql.*"%> <%@ page import="java.sql.Blob"%> <%@ page import="java.sql.PreparedStatement"%> <%@ page import="java.sql.BatchUpdateException"%> <%@ page import="javax.servlet.*"%> <%@ page import="javax.servlet.http.*"%> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <title>My JSP 'p.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> </head> <body> <% int activityId = Integer.parseInt(request.getParameter("activityId")); String name = request.getParameter("name"); String activityType = request.getParameter("activityType"); int parentId = Integer.parseInt(request.getParameter("parentId")); String description = request.getParameter("description"); %> <% Connection conn=null; PreparedStatement pstatement = null; try{ Class.forName("com.mysql.jdbc.Driver"); conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/pol","root","1234"); Statement st=conn.createStatement(); String queryString = "INSERT INTO activity(activityId,name,activityType,parentId,description)" + " VALUES (?, ?, ?, ?, ?)"; pstatement = conn.prepareStatement(queryString); pstatement.setInt(1, activityId); pstatement.setString(2, name); pstatement.setString(3, activityType); pstatement.setInt(4, parentId); pstatement.setString(5, description); } catch (Exception ex) { out.println("Unable to connect to batabase."); } finally { pstatement.close(); conn.close(); } %> </body> </html>

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  • Javascript and Twitter API rate limitation? (Changing variable values in a loop)

    - by Pablo
    Hello, I have adapted an script from an example of http://github.com/remy/twitterlib. It´s a script that makes one query each 10 seconds to my Twitter timeline, to get only the messages that begin with a musical notation. It´s already working, but I don´t know it is the better way to do this... The Twitter API has a rate limit of 150 IP access per hour (queries from the same user). At this time, my Twitter API is blocked at 25 minutes because the 10 seconds frecuency between posts. If I set up a frecuency of 25 seconds between post, I am below the rate limit per hour, but the first 10 posts are shown so slowly. I think this way I can guarantee to be below the Twitter API rate limit and show the first 10 posts at normal speed: For the first 10 posts, I would like to set a frecuency of 5 seconds between queries. For the rest of the posts, I would like to set a frecuency of 25 seconds between queries. I think if making somewhere in the code a loop with the previous sentences, setting the "frecuency" value from 5000 to 25000 after the 10th query (or after 50 seconds, it´s the same), that´s it... Can you help me on modify this code below to make it work? Thank you in advance. var Queue = function (delay, callback) { var q = [], timer = null, processed = {}, empty = null, ignoreRT = twitterlib.filter.format('-"RT @"'); function process() { var item = null; if (q.length) { callback(q.shift()); } else { this.stop(); setTimeout(empty, 5000); } return this; } return { push: function (item) { var green = [], i; if (!(item instanceof Array)) { item = [item]; } if (timer == null && q.length == 0) { this.start(); } for (i = 0; i < item.length; i++) { if (!processed[item[i].id] && twitterlib.filter.match(item[i], ignoreRT)) { processed[item[i].id] = true; q.push(item[i]); } } q = q.sort(function (a, b) { return a.id > b.id; }); return this; }, start: function () { if (timer == null) { timer = setInterval(process, delay); } return this; }, stop: function () { clearInterval(timer); timer = null; return this; }, empty: function (fn) { empty = fn; return this; }, q: q, next: process }; }; $.extend($.expr[':'], { below: function (a, i, m) { var y = m[3]; return $(a).offset().top y; } }); function renderTweet(data) { var html = ''; html += ''; html += twitterlib.ify.clean(data.text); html += ''; since_id = data.id; return html; } function passToQueue(data) { if (data.length) { twitterQueue.push(data.reverse()); } } var frecuency = 10000; // The lapse between each new Queue var since_id = 1; var run = function () { twitterlib .timeline('twitteruser', { filter : "'?'", limit: 10 }, passToQueue) }; var twitterQueue = new Queue(frecuency, function (item) { var tweet = $(renderTweet(item)); var tweetClone = tweet.clone().hide().css({ visibility: 'hidden' }).prependTo('#tweets').slideDown(1000); tweet.css({ top: -200, position: 'absolute' }).prependTo('#tweets').animate({ top: 0 }, 1000, function () { tweetClone.css({ visibility: 'visible' }); $(this).remove(); }); $('#tweets p:below(' + window.innerHeight + ')').remove(); }).empty(run); run();

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  • Visual Studio reports that not all code path return a value, even though they do

    - by chris12892
    I have an API in NETMF C# that I am writing that includes a function to send an HTTP request. For those who are familiar with NETMF, this is a heavily modified version of the "webClient" example, which a simple application that demonstrates how to submit an HTTP request, and recive a response. In the sample, it simply prints the response and returns void,. In my version, however, I need it to return the HTTP response. For some reason, Visual Studio reports that not all code paths return a value, even though, as far as I can tell, they do. Here is my code... /// <summary> /// This is a modified webClient /// </summary> /// <param name="url"></param> private string httpRequest(string url) { // Create an HTTP Web request. HttpWebRequest request = HttpWebRequest.Create(url) as HttpWebRequest; // Set request.KeepAlive to use a persistent connection. request.KeepAlive = true; // Get a response from the server. WebResponse resp = request.GetResponse(); // Get the network response stream to read the page data. if (resp != null) { Stream respStream = resp.GetResponseStream(); string page = ""; byte[] byteData = new byte[4096]; char[] charData = new char[4096]; int bytesRead = 0; Decoder UTF8decoder = System.Text.Encoding.UTF8.GetDecoder(); int totalBytes = 0; // allow 5 seconds for reading the stream respStream.ReadTimeout = 5000; // If we know the content length, read exactly that amount of // data; otherwise, read until there is nothing left to read. if (resp.ContentLength != -1) { for (int dataRem = (int)resp.ContentLength; dataRem > 0; ) { Thread.Sleep(500); bytesRead = respStream.Read(byteData, 0, byteData.Length); if (bytesRead == 0) throw new Exception("Data laes than expected"); dataRem -= bytesRead; // Convert from bytes to chars, and add to the page // string. int byteUsed, charUsed; bool completed = false; totalBytes += bytesRead; UTF8decoder.Convert(byteData, 0, bytesRead, charData, 0, bytesRead, true, out byteUsed, out charUsed, out completed); page = page + new String(charData, 0, charUsed); } page = new String(System.Text.Encoding.UTF8.GetChars(byteData)); } else throw new Exception("No content-Length reported"); // Close the response stream. For Keep-Alive streams, the // stream will remain open and will be pushed into the unused // stream list. resp.Close(); return page; } } Any ideas? Thanks...

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  • missing table in SQLite with specific version of HTC DESIRE HD

    - by William
    My application has a SQLite database in the asset folder. When the user launches my application, the database is created and the tables too. This works fine with a lot of devices (Nexus One, Htc Magic, SGS, X10… and even Htc Desire HD v2.2). My application works with all versions of Android (tested on my device (1.6, 2.2, 2.2.1 Htc Magic) and on the emulator (v1,5 until v2.3). I have just a problem with HTC DESIRE HD v2.2.1 1.72.405.3. The logcat: android.database.sqlite.SQLiteException: no such table: LISTE: , while compiling: select _id from LISTE at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2833) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2854) at android.app.ActivityThread.access$2300(ActivityThread.java:136) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2179) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:143) at android.app.ActivityThread.main(ActivityThread.java:5068) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:521) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) at dalvik.system.NativeStart.main(Native Method) Caused by: android.database.sqlite.SQLiteException: no such table: LISTE: , while compiling: select _id from LISTE at android.database.sqlite.SQLiteCompiledSql.native_compile(Native Method) at android.database.sqlite.SQLiteCompiledSql.compile(SQLiteCompiledSql.java:91) at android.database.sqlite.SQLiteCompiledSql.(SQLiteCompiledSql.java:64) at android.database.sqlite.SQLiteProgram.(SQLiteProgram.java:80) at android.database.sqlite.SQLiteQuery.(SQLiteQuery.java:46) at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:53) at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1417) at android.database.sqlite.SQLiteDatabase.rawQuery(SQLiteDatabase.java:1387) ... 11 more My application create the database but it doesn’t copy the tables of the file of the asset folder in data\data\packagename\databases\mydatabase. My code: public void createDataBase() throws IOException{ boolean dbExist = checkDataBase(); if(dbExist){ //do nothing - database already exist }else{ //By calling this method and empty database will be created into the default system path //of your application so we are gonna be able to overwrite that database with our database. this.getReadableDatabase(); try { copyDataBase(); } catch (IOException e) { throw new Error("Error copying database"); } } } private void copyDataBase() throws IOException{ //Open your local db as the input stream InputStream myInput = myContext.getAssets().open(DB_NAME); // Path to the just created empty db String outFileName = DB_PATH + DB_NAME; //Open the empty db as the output stream OutputStream myOutput = new FileOutputStream(outFileName); //transfer bytes from the inputfile to the outputfile byte[] buffer = new byte[1024]; int length; while ((length = myInput.read(buffer))!= -1){ if (length > 0){ myOutput.write(buffer, 0, length); } } //Close the streams myOutput.flush(); myOutput.close(); myInput.close(); } I think that the copydatabase function has a problem but I don't see. This code works fine with all devices except the HTC DESIRE HD v2.2.1 1.72.405.3. What problems might exist here for the HTC Desire with the given version above? How can this be remedied?

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  • Mbean registered but not found in mbean Server

    - by Prisco
    I have a problem about the mbeans. I have created a simple mbean and I have registered it on the default mBeanServer that is run (Via eclipse or java -jar mbean.jar) and in the same process if I try to fouund the mbean registered with a simple query: for (ObjectInstance instance : mbs.queryMBeans(ObjectNameMbean, null)) { System.out.println(instance.toString()); } the query retuerns my mbean, but if I start another process and try to search this mbean registered the mbeas is not found! why? The approch is : (Process that is running) public static void main(String[] args) throws Exception { MBeanServer mbeanServer =ManagementFactory.getPlatformMBeanServer(); ObjectName objectName = new ObjectName(ObjectNameMbean); Simple simple = new Simple (1, 0); mbeanServer.registerMBean(simple, objectName); while (true) { wait (Is this necessary?) } } So this is the first process that is running (that has the only pourpose to registry the mbean, because there is another process that want to read these informations. So I start another process to search this mbean but nothing. I 'm not using jboss but the local Java virtual Machine but my scope is to deploy this simple application in one ejb (autostart) and another ejb will read all informations. All suggestions are really apprecciated. This example should be more useful : Object Hello: public class Hello implements HelloMBean { public void sayHello() { System.out.println("hello, world"); } public int add(int x, int y) { return x + y; } public String getName() { return this.name; } public int getCacheSize() { return this.cacheSize; } public synchronized void setCacheSize(int size) { this.cacheSize = size; System.out.println("Cache size now " + this.cacheSize); } private final String name = "Reginald"; private int cacheSize = DEFAULT_CACHE_SIZE; private static final int DEFAULT_CACHE_SIZE = 200; } Interface HelloBean (implemented by Hello) public interface HelloMBean { public void sayHello(); public int add(int x, int y); public String getName(); public int getCacheSize(); public void setCacheSize(int size); } Simple Main import java.lang.management.ManagementFactory; import java.util.logging.Logger; import javax.management.MBeanServer; import javax.management.ObjectName; public class Main { static Logger aLog = Logger.getLogger("MBeanTest"); public static void main(String[] args) { try{ MBeanServer mbs = ManagementFactory.getPlatformMBeanServer(); ObjectName name = new ObjectName("ApplicationDomain:type=Hello"); Hello mbean = new Hello(); mbs.registerMBean(mbean, name); // System.out.println(mbs.getAttribute(name, "Name")); aLog.info("Waiting forever..."); Thread.sleep(Long.MAX_VALUE); } catch(Exception x){ x.printStackTrace(); aLog.info("exception"); } } } So now I have exported this project as jar file and run it as "java -jar helloBean.jar" and by eclipse I have modified the main class to read informations of this read (Example "Name" attribute) by using the same objectname used to registry it . Main to read : public static void main(String[] args) { try{ MBeanServer mbs = ManagementFactory.getPlatformMBeanServer(); ObjectName name = new ObjectName("ApplicationDomain:type=Hello"); System.out.println(mbs.getAttribute(name, "Name")); } catch(Exception x){ x.printStackTrace(); aLog.info("exception"); } } But nothing, the bean is not found.

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  • How to manipulate data after its retrieved via remote database

    - by bMon
    So I've used code examples from all over the net and got my app to accurately call a .php file on my server, retrieve the JSON data, then parse the data, and print it. The problem is that its just printing to the screen for sake of the tutorial I was following, but now I need to use that data in other places and need help figuring out that process. The ultimate goal is to return my db query with map coordinates, then plot them on a google map. I have another app in which I manually plot points on a map, so I'll be integrating this app with that once I can get my head around how to correctly manipulate the data returned. public class Remote extends Activity { /** Called when the activity is first created. */ TextView txt; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); // Create a crude view - this should really be set via the layout resources // but since its an example saves declaring them in the XML. LinearLayout rootLayout = new LinearLayout(getApplicationContext()); txt = new TextView(getApplicationContext()); rootLayout.addView(txt); setContentView(rootLayout); // Set the text and call the connect function. txt.setText("Connecting..."); //call the method to run the data retreival txt.setText(getServerData(KEY_121)); } public static final String KEY_121 = "http://example.com/mydbcall.php"; private String getServerData(String returnString) { InputStream is = null; String result = ""; //the year data to send //ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(); //nameValuePairs.add(new BasicNameValuePair("year","1970")); try{ HttpClient httpclient = new DefaultHttpClient(); HttpPost httppost = new HttpPost(KEY_121); HttpResponse response = httpclient.execute(httppost); HttpEntity entity = response.getEntity(); is = entity.getContent(); }catch(Exception e){ Log.e("log_tag", "Error in http connection "+e.toString()); } //convert response to string try{ BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8); StringBuilder sb = new StringBuilder(); String line = null; while ((line = reader.readLine()) != null) { sb.append(line + "\n"); } is.close(); result=sb.toString(); }catch(Exception e){ Log.e("log_tag", "Error converting result "+e.toString()); } //parse json data try{ JSONArray jArray = new JSONArray(result); for(int i=0;i<jArray.length();i++){ JSONObject json_data = jArray.getJSONObject(i); Log.i("log_tag","longitude: "+json_data.getDouble("longitude")+ ", latitude: "+json_data.getDouble("latitude") ); //Get an output to the screen returnString += "\n\t" + jArray.getJSONObject(i); } }catch(JSONException e){ Log.e("log_tag", "Error parsing data "+e.toString()); } return returnString; } } So the code: returnString += "\n\t" + jArray.getJSONObject(i); is what is currently printing to the screen. What I have to figure out is how to get the data into something I can reference in other spots in the program, and access the individual elements ie: double longitude = jArray.getJSONObject(3).longitude; or something to that effect.. I figure the class getServerData will have to return a Array type or something? Any help is appreciated, thanks.

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  • What am I doing wrong?, linking in C++

    - by Facon
    I'm trying to code a simple base64 encoder/decoder (to test my programming skill). I can compile it, but it doesn't link, I've this message error: C:\Documents and Settings\Facon\Escritoriog++ base64.o main.o -o prueba.exe main.o:main.cpp:(.text+0x24a): undefined reference to `Base64Encode(std::vector const&)' collect2: ld returned 1 exit status Compiler & Linker: Mingw32 3.4.5 SO: Windows XP This is my source code: base64.h: #ifndef BASE64_H #define BASE64_H #include <iostream> #include <vector> typedef unsigned char byte; std::string Base64Encode(const std::vector<byte> &array); std::vector<byte> Base64Decode(const std::string &array); #endif base64.cpp: #include "base64.h" std::string Base64Encode(std::vector<byte> &array) { const char *base64_table = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; const unsigned int size = array.size(); std::string output; for (unsigned int i = 0; (i < size); i++) { if ((size - i) > 3) { output.push_back(static_cast<char>(base64_table[array[i] >> 2])); output.push_back(static_cast<char>(base64_table[((array[i++] & 0x03) << 4) | ((array[i] & 0xF0) >> 4)])); output.push_back(static_cast<char>(base64_table[((array[i++] & 0x0F) << 2) | ((array[i] & 0xC0) >> 4)])); output.push_back(static_cast<char>(base64_table[array[i] & 0x3F])); } else if ((size - i) == 3) { output.push_back(static_cast<char>(base64_table[array[i] >> 2])); output.push_back(static_cast<char>(base64_table[((array[i++] & 0x03) << 4) | ((array[i] & 0xF0) >> 4)])); output.push_back(static_cast<char>(base64_table[(array[i] & 0x0F) << 2])); output.push_back(static_cast<char>('=')); } else if ((size - i) == 2) { output.push_back(static_cast<char>(base64_table[array[i] >> 2])); output.push_back(static_cast<char>(base64_table[(array[i] & 0x03) << 4])); output.push_back('='); output.push_back('='); } } return output; } std::vector<byte> Base64Decode(const std::string &array) // TODO { const char *base64_table = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; } main.cpp: #include <iostream> #include <vector> #include "base64.h" using namespace std; int main(int argc, char *argv[]) { const char* prueba = "sure."; vector<byte> texto; string codificado; for (unsigned int i = 0; (prueba[i] != 0); i++) { texto.push_back(prueba[i]); } codificado = Base64Encode(texto); cout << codificado; return 0; } PD: Sorry for my bad knowledge of English :P

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  • Logcat error: "addView(View, LayoutParams) is not supported in AdapterView" in a ListView

    - by HacKreatorz
    I'm doing an aplication for Android and something I need is that it shows a list of all files and directories in the SD Card and it has to be able to move through the different directories. I found a good tutorial in anddev: http://bit.ly/h4GyFC I modified a few things so the aplication moves in the SD Card and not in Android root Directories but the rest is mostly the same. This is my xml file for the activity: <?xml version="1.0" encoding="utf-8"?> <ListView xmlns:android="http://schemas.android.com/apk/res/android" android:id="@id/android:list" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" /> </ListView> And this is the code for the Activity: import hackreatorz.cifrador.R; import java.io.File; import java.util.ArrayList; import android.app.ListActivity; import android.content.res.Configuration; import android.os.Bundle; import android.view.View; import android.widget.ArrayAdapter; import android.widget.ListView; import android.widget.Toast; public class ArchivosSD extends ListActivity { private ArrayList<String> directoryEntries = new ArrayList<String>(); private File currentDirectory = new File("/sdcard/"); @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); browseToSD(); } @Override public void onConfigurationChanged(Configuration newConfig) { super.onConfigurationChanged(newConfig); } private void browseToSD() { browseTo(new File("/sdcard/")); } private void upOneLevel() { if(this.currentDirectory.getParent() != null) this.browseTo(this.currentDirectory.getParentFile()); } private void browseTo(final File directory) { if (directory.isDirectory()) { this.currentDirectory = directory; fill(directory.listFiles()); } else { Toast.makeText(ArchivosSD.this, this.directoryEntries.get(this.getSelectedItemPosition()), Toast.LENGTH_SHORT).show(); } } private void fill(File[] files) { this.directoryEntries.clear(); this.directoryEntries.add(getString(R.string.current_dir)); if(this.currentDirectory.getParent() != null) this.directoryEntries.add(getString(R.string.up_one_level)); int currentPathStringLength = (int) this.currentDirectory.getAbsoluteFile().length(); for (File file : files) { this.directoryEntries.add(file.getAbsolutePath().substring(currentPathStringLength)); } setListAdapter(new ArrayAdapter<String>(this, R.layout.archivos_sd, this.directoryEntries)); } @Override protected void onListItemClick(ListView l, View v, int position, long id) { int selectionRowID = (int) this.getSelectedItemPosition(); String selectedFileString = this.directoryEntries.get(selectionRowID); if (selectedFileString.equals(".")) { this.browseToSD(); } else if(selectedFileString.equals("..")) { this.upOneLevel(); } else { File clickedFile = null; clickedFile = new File(this.currentDirectory.getAbsolutePath() + this.directoryEntries.get(selectionRowID)); if(clickedFile != null) this.browseTo(clickedFile); } } } I don't get any errores in Eclipse, but I get a Force Close when running the aplication on my phone and when I look at Logcat I see the following: 01-01 23:30:29.858: ERROR/AndroidRuntime(14911): FATAL EXCEPTION: main *01-01 23:30:29.858: ERROR/AndroidRuntime(14911): java.lang.UnsupportedOperationException: addView(View, LayoutParams) is not supported in AdapterView* I don't have a clue what to do, I've looked up in Google and I didn't find anything and I did the same at stackoverflow. This is my first aplication in Java and for Android so I'm a real n00b and if the answer was there, I didn't understand it so I would really apreciate if you could explain what I should do to fix this error and why. Thanks for everything in advanced.

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  • ValidationProperty not returning entered value for textbox

    - by nat
    hi I have a custom control, (relevant code at the bottom) it consists of some text/links and a hidden textbox (rather than a hidden input). when rendered, the user via another dialog and some JS sets the value of the textbox to an integer and clicks submit on the form. i am trying to assure that the user has entered a number (via the JS) and that the textbox is not still set to its default of "0" the requiredfieldvalidator works just fine, if i dont change the value it spots it on the client and fills the validation summary on the page with the appropriate message. unfortunately when i do fill the textbox, the validator also rejests the post as the controls textbox text value is still set to "0", even though on the form it has changed. clearly i am doing something wrong.. but cant work out what it is? could someone enlighten me please, this is driving me potty if i step through the code, when the get of the mediaidtext is hit,the findcontrol finds the textbox, but the value is still set to "0" many thanks code below nat [ValidationProperty("MediaIdText")] public class MediaLibraryFileControl: CompositeControl { private int mediaId = 0; public int MediaId { get { return mediaId; } set { mediaId = value; } } public string MediaIdText { get { string txt = "0"; Control ctrl = this.FindControl(this.UniqueID+ "_hidden"); try { txt = ((TextBox)ctrl).Text; MediaId = Convert.ToInt32(txt); } catch { MediaId = 0; } return txt; } } protected override void CreateChildControls() { this.Controls.Add(new LiteralControl("<span>")); this.Controls.Add(new LiteralControl("<span id=\"" + TextControlName + "\">" + getMediaDetails() + "</span>")); TextBox tb = new TextBox(); tb.Text = this.MediaId.ToString(); tb.ID = this.UniqueID + "_hidden"; tb.CssClass = "hidden"; this.Controls.Add(tb); if (Select == true) { this.Controls.Add(new LiteralControl(string.Format("&nbsp;[<a href=\"javascript:{0}(this,'{1}','{2}')\" class=\"select\">{3}</a>]", dialog, this.UniqueID, this.categoryId, "select"))); this.Controls.Add(new LiteralControl(string.Format("&nbsp;[<a href=\"javascript:{0}(this,'{1}')\" class=\"select\">{2}</a>]", clearDialog, this.ID, "clear"))); } this.Controls.Add(new LiteralControl("</span>")); } protected virtual string getMediaDetails() { //... return String.Empty; } } this is the code adding the validationcontrol the editcontrol is the instance of the control above public override Control RenderValidationControl(Control editControl) { Control ctrl = new PlaceHolder(); RequiredFieldValidator req = new RequiredFieldValidator(); req.ID = editControl.ClientID + "_validator"; req.ControlToValidate = editControl.ID; req.Display = ValidatorDisplay.None; req.InitialValue = "0"; req.EnableClientScript = false; req.ErrorMessage = "control cannot be blank"; ctrl.Controls.Add(req); return ctrl; }

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  • C# ambiguity in Func + extension methods + lambdas

    - by Hobbes
    I've been trying to make my way through this article: http://blogs.msdn.com/wesdyer/archive/2008/01/11/the-marvels-of-monads.aspx ... And something on page 1 made me uncomfortable. In particular, I was trying to wrap my head around the Compose<() function, and I wrote an example for myself. Consider the following two Func's: Func<double, double> addTenth = x => x + 0.10; Func<double, string> toPercentString = x => (x * 100.0).ToString() + "%"; No problem! It's easy to understand what these two do. Now, following the example from the article, you can write a generic extension method to compose these functions, like so: public static class ExtensionMethods { public static Func<TInput, TLastOutput> Compose<TInput, TFirstOutput, TLastOutput>( this Func<TFirstOutput, TLastOutput> toPercentString, Func<TInput, TFirstOutput> addTenth) { return input => toPercentString(addTenth(input)); } } Fine. So now you can say: string x = toPercentString.Compose<double, double, string>(addTenth)(0.4); And you get the string "50%" So far, so good. But there's something ambiguous here. Let's say you write another extension method, so now you have two functions: public static class ExtensionMethods { public static Func<TInput, TLastOutput> Compose<TInput, TFirstOutput, TLastOutput>( this Func<TFirstOutput, TLastOutput> toPercentString, Func<TInput, TFirstOutput> addTenth) { return input => toPercentString(addTenth(input)); } public static Func<double, string> Compose<TInput, TFirstOutput, TLastOutput>(this Func<double, string> toPercentString, Func<double, double> addTenth) { return input => toPercentString(addTenth(input + 99999)); } } Herein is the ambiguity. Don't these two function have overlapping signatures? Yes. Does this even compile? Yes. Which one get's called? The second one (which clearly gives you the "wrong" result) gets called. If you comment out either function, it still compiles, but you get different results. It seems like nitpicking, but there's something that deeply offends my sensibilities here, and I can't put my finger on it. Does it have to do with extension methods? Does it have to do with lambdas? Or does it have to do with how Func< allows you to parameterize the return type? I'm not sure. I'm guessing that this is all addressed somewhere in the spec, but I don't even know what to Google to find this. Help!

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