Search Results

Search found 21054 results on 843 pages for 'void'.

Page 253/843 | < Previous Page | 249 250 251 252 253 254 255 256 257 258 259 260  | Next Page >

  • Bad Design? Constructor of composition uses `this`

    - by tanascius
    Example: class MyClass { Composition m_Composition; void MyClass() { m_Composition = new Composition( this ); } } I am interested in using depenency-injection here. So I will have to refactor the constructor to something like: void MyClass( Composition composition ) { m_Composition = composition; } However I get a problem now, since the Composition-object relies on the object of type MyClass which is just created. Can a dependency container resolve this? Is it supposed to do so? Or is it just bad design from the beginning on?

    Read the article

  • interface as a method parameter in Java

    - by PeterYu
    Hi all, I had an interview days ago and was thrown a question like this. Q: Reverse a linked list. Following code is given: public class ReverseList { interface NodeList { int getItem(); NodeList nextNode(); } void reverse(NodeList node) { } public static void main(String[] args) { } } I was confused because I did not know an interface object could be used as a method parameter. The interviewer explained a little bit but I am still not sure about this. Could somebody enlighten me?

    Read the article

  • Why is 'virtual' optional for overridden methods in derived classes?

    - by squelart
    When a method is declared as virtual in a class, its overrides in derived classes are automatically considered virtual as well, and the C++ language makes this keyword virtual optional in this case: class Base { virtual void f(); }; class Derived : public Base { void f(); // 'virtual' is optional but implied. }; My question is: What is the rationale for making virtual optional? I know that it is not absolutely necessary for the compiler to be told that, but I would think that developers would benefit if such a constraint was enforced by the compiler. E.g., sometimes when I read others' code I wonder if a method is virtual and I have to track down its superclasses to determine that. And some coding standards (Google) make it a 'must' to put the virtual keyword in all subclasses.

    Read the article

  • AnimationDrawable, when does it end?

    - by Syb
    I know there have been several people with the same question. Which is: How do i know when a frame by frame animation has ended? I have not had any useful answer on fora i visited. So i thought, let's see if they know at stackoverflow. But I could not sit still in the mean time, so i made a work around of this, but it does not really work the way i would like it to. here is the code: public class Main extends Activity { AnimationDrawable sybAnimation; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); ImageView imageView = (ImageView)findViewById(R.id.ImageView01); imageView.setBackgroundResource(R.anim.testanimation); sybAnimation = (AnimationDrawable) imageView.getBackground(); imageView.post(new Starter()); } class Starter implements Runnable { public void run() { sybAnimation.start(); long totalDuration = 0; for(int i = 0; i< sybAnimation.getNumberOfFrames();i++){ totalDuration += sybAnimation.getDuration(i); } Timer timer = new Timer(); timer.schedule(new AnimationFollowUpTimerTask(R.id.ImageView01, R.anim.testanimation_reverse),totalDuration); } } class AnimationFollowUpTimerTask extends TimerTask { private int id; private int animationToRunId; public AnimationFollowUpTimerTask(int idOfImageView, int animationXML){ id = idOfImageView; animationToRunId = animationXML; } @Override public void run() { ImageView imageView = (ImageView)findViewById(id); imageView.setBackgroundResource(animationToRunId); AnimationDrawable anim = (AnimationDrawable) imageView.getBackground(); anim.start(); } } basically I make a timertask which is scheduled with the same time as the animation to take. In that run() I want to load a new animation into the imageView and start that animation, this however does not work. Does anyone know how to get this to work, or even better, have a better way to find out when an AnimationDrawable has ended its animation?

    Read the article

  • Magick++ in VS2010 - unresolved external symbol

    - by FlashFan
    Hey guys! I'm trying to use ImageMagick Magick++ for a C++ Project in VS2010. I installed the Library from here: klick Then in my Project, I added c:/program files/ImageMagick-6.6.6-Q16/include to the include folders. Then I tried to use Magick++ with this code: #include <Magick++.h> void main(int argc, char ** argv){ InitializeMagick(*argv); } But this does not work! VS2010 returns the following errors: error LNK2001: unresolved external symbol "__declspec(dllimport) void __cdecl Magick::InitializeMagick(char const *)" (__imp_?InitializeMagick@Magick@@YAXPBD@Z) error LNK1120: 1 unresolved externals What am I doing wrong? Thanks very much for your help!

    Read the article

  • What is the effect of final variable declaration in methods?

    - by Finbarr
    Classic example of a simple server: class ThreadPerTaskSocketServer { public static void main(String[] args) throws IOException { ServerSocket socket = new ServerSocket(80); while (true) { final Socket connection = socket.accept(); Runnable task = new Runnable() { public void run() { handleRequest(connection); } }; new Thread(task).start(); } } } Why should the Socket be declared as final? Is it because the new Thread that handles the request could refer back to the socket variable in the method and cause some sort of ConcurrentModificationException?

    Read the article

  • Thread Question

    - by Polaris
    I have method which create background thread to make some action. In this background thread I create object. But this object while creating in runtime give me an exception : The calling thread must be STA, because many UI components require this. I know that I must use Dispatcher to make reflect something to UI. But in this case I just create an object and dont iteract with UI. This is my code: public void SomeMethod() { BackgroundWorker worker = new BackgroundWorker(); worker.DoWork += new DoWorkEventHandler(Background_Method); worker.RunWorkerAsync(); } void Background_Method(object sender, DoWorkEventArgs e) { TreeView tv = new TreeView(); } How can I create objects in background thread? I use WPF application

    Read the article

  • Calling a JAVA method from C++ with JNI, no parameters

    - by PRNDL Development Studios
    Please bear with me, I am an iPhone developer and this whole android this confuses me a bit. I have some c++ methods that are called from a cocos2d-x CCMenuItem. Therefore I cannot send any parameters, according to the docs. I need to open a url with the android browser which will require me to call a JAVA function to start a new intent. I understand that I need to create a VM, however the below code gives me the error: jni/../../Classes/MyClass.cpp:184: error: 'JNI_CreateJavaVM' was not declared in this scope I was looking at this thread: Calling a java method from c++ in Android But he uses parameters, and I can't do that. And I don't see where those are in his code to just make them myself. I don't know what the string should be in the 'Find Class' method. Also, I assume it is pretty terrible to create a new VM instance in every method I need to call. How would I create one as a singleton to use across the board? This is my c++ code called by my menu item: #include <jni.h> ... JavaVM *vm; // Global ... void OptionsScene::website(){ JNIEnv *env; JavaVMInitArgs vm_args; vm_args.version = JNI_VERSION_1_2; vm_args.nOptions = 0; vm_args.ignoreUnrecognized = 1; jint result = JNI_CreateJavaVM(&vm, (void **)&env, &vm_args); // This line still errors jclass clazz = env->FindClass("com/prndl/project/WebExecute"); jmethodID method = env->GetMethodID(clazz, "website", "(Ljava/lang/String;)V"); env->CallVoidMethod(NULL,method); vm->DestroyJavaVM(); And this is the JAVA Method that I need to call: public class WebExecute extends Activity{ public void website(){ Intent browserIntent = new Intent(Intent.ACTION_VIEW, Uri.parse("http://www.google.com")); startActivity(browserIntent); } } Honestly, I am struggling with this, any help is appreciated. Thanks.

    Read the article

  • .Net - interop assemblies taking 15 seconds to load when being referenced in a function

    - by Jon
    This is a C# console application. I have a function that does something like this: static void foo() { Application powerpointApp; Presentation presentation = null; powerpointApp = new Microsoft.Office.Interop.PowerPoint.ApplicationClass(); } That's all it does. When it is called there is a fifteen second delay before the function gets hit. I added something like this: static void MyAssemblyLoadEventHandler(object sender, AssemblyLoadEventArgs args) { Console.WriteLine(DateTime.Now.ToString() + " ASSEMBLY LOADED: " + args.LoadedAssembly.FullName); Console.WriteLine(); } This gets fired telling me that my interop assemblies have been loaded about 10 milliseconds before my foo function gets hit. What can I do about this? The program needs to call this function (and eventually do something else) once and then exit so I need for these assemblies to be cached or something. Ideas?

    Read the article

  • Validation of method parameters

    - by Anton Tsivarev
    I have a RESTful web service. For implementation using JAX-RS (Jersey). Have the following method: public void foo (@PathParam ("name") String uuid) { ... } I need to do validation of input parameters. And if data invalid throw WebApplicationException. I added my custom annotation CheckUuid (extends ): public void foo (@PathParam ("name") @CheckUuid String uuid) { ... } Is it possible to do validation using annotations on a stage when the method chosen, but not yet called? For example using PreProcessInterceptor?

    Read the article

  • Can I compose a WCF callback contract out of multiple interfaces?

    - by mafutrct
    Followup question to http://stackoverflow.com/questions/2502930/how-can-i-compose-a-wcf-contract-out-of-multiple-interfaces. I tried to merge multiple callback interfaces in a single interface. This yields an InvalidOperationException claiming that the final interface contains no operations. Technically, this is true, however, the inherited interfaces do contain operations. How can I fix this? Or is this a limitation of WCF? Edit: interface A { [OperationContract]void X(); } interface B { [OperationContract]void Y(); } interface C: A, B {} // this is the public callback contract

    Read the article

  • Copy image to BLOB from client pc aka Java function in Oracle

    - by mumich
    Hi guys, I've been stuck with this for past two days. I've go java function stored in Oracle system which is supposed to copy image from local drive do remote database and store it in BLOB - it's called CopyBLOB and looks like this: import java.sql.*; import oracle.sql.*; import java.io.*; public class CopyBLOB { static int id; static String fileName = null; static Connection conn = null; public CopyBLOB(int idz, String f) { id = idz; fileName = f; } public static void copy(int ident, String path) throws SQLException, FileNotFoundException { CopyBLOB cpB = new CopyBLOB(ident, path); cpB.getConnection(); cpB.callUpdate(id, fileName); } public void getConnection() throws SQLException { DriverManager.registerDriver (new oracle.jdbc.OracleDriver()); try { conn = DriverManager.getConnection("jdbc:oracle:thin:@oraserv.ms.mff.cuni.cz:1521:db", "xxx", "xxx"); } catch (SQLException sqlex) { System.out.println("SQLException while getting db connection: "+sqlex); if (conn != null) conn.close(); } catch (Exception ex) { System.out.println("Exception while getting db connection: "+ex); if (conn != null) conn.close(); } } public void callUpdate(int id, String file ) throws SQLException, FileNotFoundException { CallableStatement cs = null; try { conn.setAutoCommit(false); File f = new File(file); FileInputStream fin = new FileInputStream(f); cs = (CallableStatement) conn.prepareCall( "begin add_image(?,?); end;" ); cs.setInt(1, id ); cs.setBinaryStream(2, fin, (int) f.length()); cs.execute(); conn.setAutoCommit(true); } catch ( SQLException sqlex ) { System.out.println("SQLException in callUpdateUsingStream method of given status : " + sqlex.getMessage() ); } catch ( FileNotFoundException fnex ) { System.out.println("FileNotFoundException in callUpdateUsingStream method of given status : " + fnex.getMessage() ); } finally { try { if (cs != null) cs.close(); if (conn != null) conn.close(); } catch ( Exception ex ) { System.out.println("Some exception in callUpdateUsingStream method of given status : " + ex.getMessage( ) ); } } } } The wrapper function is defined in package "MyPackage" as folows: procedure image_adder( id varchar2, path varchar2 ) AS language java name 'CopyBLOB.copy(java.lang.String, java.lang.String)'; And the inserting function called image_add is as simple as this: procedure add_image( id numeric(10), pic blob) AS BEGIN insert into pictures values (seq_pic.nextval, id, pic); END add_image; Now the problem: When I type call MyPackage.image_adder(1, 'd:\samples\img.jpg'); I get the ORA-29531 Error: No method copy in class CopyBLOB. Can you help me, please?

    Read the article

  • Pointer to another classs as a property

    - by arjacsoh
    Why I receive an error when I try to create a property to another class through a pointer like that: #ifndef SQUARE_H #define SQUARE_H #include <string> //using namespace std; #include "Player.h" class Square { public: Square(int); void process(); protected: int ID; Player* PlayerOn; <--- }; #endif and the Player class is : #ifndef PLAYER_H #define PLAYER_H #include <string> //using namespace std; #include "Square.h" class Player { public: Player(int,int); // ~Player(void); int playDice(); private: int ID; int money; }; #endif I receive: syntax error missing ; before * (on the declaration of Player* PlayerOn;) and missing type specifier (on the same line...)

    Read the article

  • Calling class in Java after editing file used in as source for table

    - by user2892290
    I'm currently working on a project, I'll try to subrscibe first. I save data into text file, that I use as a source for browser of that data. The browser is based on table that contains the data. I have to rewrite the source file everytime I delete or edit data. That's where the problem comes in. After deleting or editing data I call a method to create the table again, but the table never creates. Is it possibly made by editing the file and calling the method right after that? If I restart my app the table is successfully created with right data. Take in note that I don't get any error message. This is the method I use for loading data from source file: try (BufferedReader input1 = new BufferedReader(new FileReader("./src/data.src"))) { int lines = 0; while (input1.read() != -1) { if (!(input1.readLine()).equals("")) { lines++; } } input1.close(); if (lines == 0) { JOptionPane.showMessageDialog(null, "No data to load, create a note first!"); new Writer().build(frame); } else { try (BufferedReader input = new BufferedReader(new FileReader("./src/data.src"))) { Game[] g = new Game[lines]; String currentLine; String[] help; int counter = 0; while (lines > 0) { currentLine = input.readLine(); help = currentLine.split("#"); g[counter] = new Game(help[0],help[1], help[2], help[3], help[4], help[5], help[6], help[7], help[8], help[9]); counter++; lines--; } input.close(); final JButton bButton = new backButton().create(frame, mPanel); build(g, frame, bButton); mPanel.add(panel); mPanel.add(panel2); mPanel.add(searchPanel); mPanel.add(bButton); bButton.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { frame.setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR)); panel.removeAll(); frame.setCursor(Cursor.getDefaultCursor()); } }); mPanel.setPreferredSize(new Dimension(1000, 750)); panel.setBorder(new EmptyBorder(10, 10, 10, 10)); frame.setLayout(new FlowLayout()); frame.add(mPanel); frame.pack(); JMenuBar menuBar = new Menu().create(frame, mPanel); frame.setJMenuBar(menuBar); frame.setVisible(true); Rectangle rec = GraphicsEnvironment.getLocalGraphicsEnvironment().getMaximumWindowBounds(); int width = (int) rec.getWidth(); int height = (int) rec.getHeight(); frame.setBounds(1, 3, width, height); frame.addComponentListener(new ComponentAdapter() { @Override public void componentMoved(ComponentEvent e) { frame.setLocation(1, 3); } }); And this is the method I use for creating the table: String[][] tableData = new String[g.length][9]; for (int i = 0; i < tableData.length; i++) { tableData[i][0] = g[i].getChampion(); tableData[i][1] = g[i].getRole(); tableData[i][2] = g[i].getEnemy(); tableData[i][3] = g[i].getDifficulty(); tableData[i][4] = g[i].getResult(); tableData[i][5] = g[i].getScore(); tableData[i][6] = g[i].getGameType(); tableData[i][7] = g[i].getPoints(); tableData[i][8] = g[i].getLeague(); } final JLabel searchLabel = new JLabel("Search for champion played."); final JButton searchButton = new JButton("Search"); final JTextField searchText = new JTextField(20); frame.setTitle("LoL Notepad - reading your notes"); JTable table = new JTable(tableData, columnNames); final JScrollPane scrollPane = new JScrollPane(table); scrollPane.setPreferredSize(new Dimension(980, 500)); panel2.setPreferredSize(new Dimension(1000, 550)); panel2.setVisible(false); panel2.setBorder(new EmptyBorder(10, 10, 10, 10)); panel3.setVisible(false); panel.setLayout(new FlowLayout()); panel.add(scrollPane); searchPanel.add(searchLabel); searchPanel.add(searchText); searchPanel.add(searchButton); searchButton.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { try { frame.setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR)); search(g, searchText.getText(), frame, bButton); frame.setCursor(Cursor.getDefaultCursor()); } catch (IOException ex) { Logger.getLogger(Reader.class.getName()).log(Level.SEVERE, null, ex); } } }); table.addMouseListener(new MouseAdapter() { @Override public void mousePressed(MouseEvent e) { if (e.getClickCount() == 1) { JTable target = (JTable) e.getSource(); panel.setVisible(false); searchPanel.setVisible(false); bButton.setVisible(false); int row = target.getSelectedRow(); specific(row, g, frame, bButton); } } });

    Read the article

  • Sending tweets using Android

    - by Saranya.R
    I want to send a tweet from Android.I have executed the following code.But I am not bale to send any tweets.Avtually the button I created is not working.Can anybody tel me wats the prob? This is my code.. package samplecode.sampleapp.sampletwidgitpublicintent; import android.app.Activity; import android.content.ActivityNotFoundException; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.os.Bundle; public class TwidgitPublicIntent extends Activity implements OnClickListener { private static final int TWIDGIT_REQUEST_CODE = 2564; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); ((Button)findViewById(R.id.tweet_button)).setOnClickListener(this); ((Button)findViewById(R.id.mention_button)).setOnClickListener(this); ((Button)findViewById(R.id.retweet_button)).setOnClickListener(this); ((Button)findViewById(R.id.message_button)).setOnClickListener(this); } public void onClick(View v) { switch(v.getId()) { case R.id.tweet_button: // Standard tweet Intent tIntent = new Intent("com.disretrospect.twidgit.TWEET"); tIntent.putExtra("com.disretrospect.twidgit.extras.MESSAGE", "_message_in_here_"); try { this.startActivityForResult(tIntent, TWIDGIT_REQUEST_CODE); } catch (ActivityNotFoundException e) { // If Twidgit is not installed } break; case R.id.mention_button: // Mention Intent mIntent = new Intent("com.disretrospect.twidgit.MENTION"); mIntent.putExtra("com.disretrospect.twidgit.extras.TO", "_username_to_xmention_"); mIntent.putExtra("com.disretrospect.twidgit.extras.MESSAGE", "_message_in_here_"); try { this.startActivityForResult(mIntent, TWIDGIT_REQUEST_CODE); } catch (ActivityNotFoundException e) { // If Twidgit is not installed } break; case R.id.retweet_button: // Retweet a tweet Intent rtIntent = new Intent("com.disretrospect.twidgit.RETWEET"); rtIntent.putExtra("com.disretrospect.twidgit.extras.MESSAGE", "_message_in_here_"); rtIntent.putExtra("com.disretrospect.twidgit.extras.VIA", "_original_author_of_tweet_name_"); try { this.startActivityForResult(rtIntent, TWIDGIT_REQUEST_CODE); } catch (ActivityNotFoundException e) { // If Twidgit is not installed } break; case R.id.message_button: // Send DM Intent dmIntent = new Intent("com.disretrospect.twidgit.DIRECT_MESSAGE"); dmIntent.putExtra("com.disretrospect.twidgit.extras.TO", "_username_to_send_dm_to_"); dmIntent.putExtra("com.disretrospect.twidgit.extras.MESSAGE", "_message_in_here_"); try { this.startActivityForResult(dmIntent, TWIDGIT_REQUEST_CODE); } catch (ActivityNotFoundException e) { // If Twidgit is not installed } break; } } @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { super.onActivityResult(requestCode, resultCode, data); // Check result code if(resultCode == Activity.RESULT_OK) { // Check requestCode switch(requestCode) { case TWIDGIT_REQUEST_CODE: // Handle successful return break; } } else if(resultCode == Activity.RESULT_CANCELED){ // Handle canceled activity } } }

    Read the article

  • Assigning two strings together getting Access Read Violation

    - by Jay Bell
    I am trying to pass a string to a class mutator and set the private member to that string here is the code that is sending the string void parseTradePairs(Exchange::Currency *curr, std::string *response, int begin, int exit) { int start; int end; string temp; string dataResponse; CURL *tempCurl; initializeCurl(tempCurl); int location = response->find("marketid", begin); if(location <= exit) { start = location + 11; begin = response->find("label", start); end = begin - start - 3; findStrings(start, end, temp, response); getMarketInfo(tempCurl, temp, dataResponse); curr->_coin->setExch(temp); // here is the line of code that is sending the string dataResponse >> *(curr->_coin); curr->_next = new Exchange::Currency(curr, curr->_position + 1); parseTradePairs(curr->_next, response, begin, exit); } } and here is the mutator within the coin class that is receiving the string and assigning it to _exch void Coin::setExch(string exch) { _exch = exch; } I have stepped through it and made sure that exch has the string in it. "105" but soon as it hits _exch = exch; I get the reading violation. I tried passing as pointer as well. I do not believe it should go out of scope. and the string variable in the class is initialized to zero in the default constructor but again that should matter unless I am trying to read from it instead of writing to it. /* defualt constructor */ Coin::Coin() { _id = ""; _label = ""; _code= ""; _name = ""; _marketCoin = ""; _volume = 0; _last = 0; _exch = ""; } Exchange::Exchange(std::string str) { _exch = str; _currencies = new Currency; std::string pair; std::string response; CURL *curl; initializeCurl(curl); getTradePairs(curl, response); int exit = response.find_last_of("marketid"); parseTradePairs(_currencies, &response, 0, exit); } int main(void) { CURL *curl; string str; string id; Coin coin1; initializeCurl(curl); Exchange ex("cryptsy"); curl_easy_cleanup(curl); system("pause"); return 0; } class Exchange { public: typedef struct Currency { Currency(Coin *coin, Currency *next, Currency *prev, int position) : _coin(coin), _next(next), _prev(prev), _position(position) {} Currency(Currency *prev, int position) : _prev(prev), _position(position), _next(NULL), _coin(&Coin()){} Currency() : _next(NULL), _prev(NULL), _position(0) {} Coin *_coin; Currency *_next; Currency *_prev; int _position; }; /* constructor and destructor */ Exchange(); Exchange(std::string str); ~Exchange(); /* Assignment operator */ Exchange& operator =(const Exchange& copyExchange); /* Parse Cryptsy Pairs */ friend void parseTradePairs(Currency *curr, std::string *response, int begin, int exit); private: std::string _exch; Currency *_currencies; }; here is what i changed it to to fix it. typedef struct Currency { Currency(Coin *coin, Currency *next, Currency *prev, int position) : _coin(coin), _next(next), _prev(prev), _position(position) {} Currency(Currency *prev, int position) : _prev(prev), _position(position), _next(NULL), _coin(&Coin()){} Currency() { _next = NULL; _prev = NULL; _position = 0; _coin = new Coin(); } Coin *_coin; Currency *_next; Currency *_prev; int _position; };

    Read the article

  • C++: Avoid .cpp files with only an empty (de)constructor

    - by Martijn Courteaux
    Hi, When I have a header file like this: #ifndef GAMEVIEW_H_ #define GAMEVIEW_H_ #include <SDL/SDL.h> class GameView { public: GameView(); virtual ~GameView(); virtual void Update() = 0; virtual void Render(SDL_Surface* buffer) = 0; }; #endif /* GAMEVIEW_H_ */ I need to create a .cpp file like this: #include "GameView.h" GameView::~GameView() { } GameView::GameView() { } This is a bit stupid. Just a .cpp file for an empty constructor and deconstructor. I want to implement that method simply in the header file. That is much cleaner. How to do this?

    Read the article

  • Is it possible to write a Java printf statement that prints the statement itself?

    - by polygenelubricants
    Is it possible to have a Java printf statement, whose output is the statement itself? Some snippet to illustrate: // attempt #1 public class Main { public static void main(String[] args) { System.out.printf("something"); } } This prints something. So the output of attempt #1 is not quite exactly the printf statement in attempt #1. We can try something like this: // attempt #2 public class Main { public static void main(String[] args) { System.out.printf("System.out.printf(\"something\");"); } } And now the output is System.out.printf("something"); So now the output of attempt #2 matches the statement in output #1, but we're back to the problem we had before, since we need the output of attempt #2 to match the statement in attempt #2. So is it possible to write a one-line printf statement that prints itself?

    Read the article

  • WCF methods sharing a dictionary

    - by YeomansLeo
    I'm creating a WCF Service Library and I have a question regarding thread-safety consuming a method inside this library, here is the full implementation that I have until now. namespace WCFConfiguration { [ServiceBehavior(InstanceContextMode = InstanceContextMode.PerCall, ConcurrencyMode = ConcurrencyMode.Single)] public class ConfigurationService : IConfigurationService { ConcurrentDictionary<Tuple<string,string>, string> configurationDictionary = new ConcurrentDictionary<Tuple<string,string>, string>(); public void Configuration(IEnumerable<Configuration> configurationSet) { Tuple<string, string> lookupStrings; foreach (var config in configurationSet) { lookupStrings = new Tuple<string, string>(config.BoxType, config.Size); configurationDictionary.TryAdd(lookupStrings, config.RowNumber); } } public void ScanReceived(string boxType, string size, string packerId = null) { } } } Imagine that I have a 10 values in my configurationDictionary and many people want to query this dictionary consuming ScanReceived method, are those 10 values be shared for each of the clients that request ScanReceived? Do I need to change my ServiceBehavior? The Configuration method is only consumed by one person by the way.

    Read the article

  • Action T synchronous and asynchronous

    - by raffaeu
    Hi everybody I have a contextmenustrip control that allows you to execute an action is two different flawours. Sync and Async. I am trying to covert everything using Generics so I did this: public class BaseContextMenu<T> : IContextMenu { private T executor ... public void Exec(Action<T> action){ action.Invoke(this.executor); } public void ExecAsync(Action<T> asyncAction){ ... } How I can write the async method in order to execute the generic action and 'do something' with the menu in the meanwhile? I saw that the signature of BeginInvoke is something like: asyncAction.BeginInvoke(thi.executor, IAsyncCallback, object);

    Read the article

  • wpf how to bind a listbox to a list (two ways) - c#

    - by user429400
    Hi, I want to create a 2 way bind between a listbox and a .NET list. In my GUI, I have a listbox, a textbox and add and remove buttons. The listbox displays cars, and my goal is to create a 2way bind between the .Net car list and the listbox: when the user enters a car into the textbox, it gets updated only in the .Net list, and the listbox is updated automatically. When the user press the GUI "remove" button, a car gets removed from the GUI and the .Net list is updated automatically. I've started to write the xaml code, but figured that I don't actually know how to do the binding on both sides (c# and xaml): <Window x:Class="WpfApplication1.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:c="clr-namespace:WpfApplication1" Title="Window1" Height="300" Width="369" Loaded="Window_Loaded"> <Window.Resources> <ObjectDataProvider x:Key="carsData" ObjectType="{x:Type c:Window1}" /> </Window.Resources> <Grid Width="332"> <ListBox Margin="10,62,0,100" Name="myListBox" HorizontalAlignment="Left" Width="120" ItemsSource="{Binding Source={StaticResource CarsData}}"/> <Button Height="23" Margin="66,0,0,65" Name="addBtn" VerticalAlignment="Bottom" Click="addBtn_Click" HorizontalAlignment="Left" Width="64">add</Button> <TextBox Margin="10,0,0,64.48" Name="myTextBox" Height="23" VerticalAlignment="Bottom" HorizontalAlignment="Left" Width="47" /> <Button Height="23" Margin="66,0,0,33" Name="removeButton" VerticalAlignment="Bottom" HorizontalAlignment="Left" Width="64" Click="removeButton_Click">Remove</Button> </Grid> </Window> There is my c# code: namespace WpfApplication1 { public partial class Window1 : Window { MyModel listMgr; ObservableCollection carList; public Window1() { InitializeComponent(); listMgr = new MyModel(); } private void addBtn_Click(object sender, RoutedEventArgs e) { listMgr.add(new Car(0, myTextBox.Text, 2011)); } private void removeButton_Click(object sender, RoutedEventArgs e) { //myListBox.Items.RemoveAt(0); } private void Window_Loaded(object sender, RoutedEventArgs e) { carList = listMgr.getList(); myListBox.DataContext = carList; //secondListBox.DataContext = carList; } } } Thanks, Li

    Read the article

  • How would I implement code in a .h file into the main.cpp file?

    - by Lea
    I have a c++ project I am working on. I am a little stumped at the moment. I need a little help. I need to implement code from the .h file into the main.cpp file and I am not sure how to do that. For example code code from main.cpp: switch (choice){ case 1: // open an account { cout << "Please enter the opening balence: $ "; cin >> openBal; cout << endl; cout << "Please enter the account number: "; cin >> accountNum; cout << endl; break; } case 2:// check an account { cout << "Please enter the account number: "; cin >> accountNum; cout << endl; break; } and code from the .h file: void display(ostream& out) const; // displays every item in this list through out bool retrieve(elemType& item) const; // retrieves item from this list // returns true if item is present in this list and // element in this list is copied to item // false otherwise // transformers void insert(const elemType& item); // inserts item into this list // preconditions: list is not full and // item not present in this list // postcondition: item is in this list In the .h file you would need to use the void insert under transformer in the main.cpp under case 1. How would you do that? Any help is apprecaited. I hope I didn't confuse anyone on what I am needing to know how to do. Thanks

    Read the article

  • crashing on iPhone Address API

    - by phil swenson
    Any ideas on why this code would crash (crash location indicated below)? email is a valid NSString*... ([email protected]) +(void)newContactFromEmail:(DetailViewController*)controller email:(NSString*)emailAddress{ ABNewPersonViewController *npvc = [[ABNewPersonViewController alloc] init]; ABRecordRef newPerson = ABPersonCreate(); [self updateEmail:newPerson email:emailAddress]; npvc.displayedPerson = newPerson; npvc.newPersonViewDelegate = controller; [controller.navigationController pushViewController:npvc animated:YES]; } +(void)updateEmail:(ABRecordRef)person email:(NSString*)email{ **crashes Here**---->> ABMutableMultiValueRef multiEmail = ABMultiValueCreateMutableCopy (ABRecordCopyValue(person, kABPersonEmailProperty)); ABMultiValueAddValueAndLabel(multiEmail, email, kABHomeLabel, NULL); ABRecordSetValue(person, kABPersonEmailProperty, multiEmail, nil); CFRelease(multiEmail); }

    Read the article

  • Thread feeding other MultiThreading

    - by alaamh
    I see it's easy to open pipe between two process using fork, but how we can passing open pipe to threads. Assume we need to pass out of PROGRAM A to PROGRAM B "may by more than one thread", PROGRAM B send his output to PROGRAM C #include <stdio.h> #include <stdlib.h> #include <pthread.h> struct targ_s { char* reader; }; void *thread1(void *arg) { struct targ_s *targ = (struct targ_s*) arg; int status, fd[2]; pid_t pid; pipe(fd); pid = fork(); if (pid == 0) { int fd = fileno( targ->fd_reader ); dup2(STDIN_FILENO, fd); close(fd[0]); dup2(fd[1], STDOUT_FILENO); close(fd[1]); execvp ("PROGRAM B", NULL); exit(1); } else { close(fd[1]); dup2(fd[0], STDIN_FILENO); close(fd[0]); execl("PROGRAM C", NULL); wait(&status); return NULL; } } int main(void) { FILE *fpipe; char *command = "PROGRAM A"; char buffer[1024]; if (!(fpipe = (FILE*) popen(command, "r"))) { perror("Problems with pipe"); exit(1); } char* outfile = "out.dat"; FILE* f = fopen (outfile, "wb"); int fd = fileno( f ); struct targ_s targ; targ.fd_reader = outfile; pthread_t thid; if (pthread_create(&thid, NULL, thread1, &targ) != 0) { perror("pthread_create() error"); exit(1); } int len; while (read(fpipe, buffer, sizeof (buffer)) != 0) { len = strlen(buffer); write(fd, buffer, len); } pclose(fpipe); return (0); }

    Read the article

< Previous Page | 249 250 251 252 253 254 255 256 257 258 259 260  | Next Page >