Search Results

Search found 18450 results on 738 pages for 'mobile programming'.

Page 247/738 | < Previous Page | 243 244 245 246 247 248 249 250 251 252 253 254  | Next Page >

  • what's an option strict and explicit?

    - by Ygam
    I saw this post: "Typos… Just use option strict and explicit please.. during one software development project, which I was on as a consultant, they were getting ridiculous amounts of errors everywhere… turned out the developer couldn’t spell and would declare variables with incorrect spelling.. no big deal, until you use the correct spelling when you’re assigning a value to it… and you had option explicit off. Ouch to them…" what is an option strict and explicit anyway? I have googled it up but can't get the idea (because mostly it's Visual Basic, I'm doing PHP)

    Read the article

  • Parsing language for both binary and character files

    - by Thorsten S.
    The problem: You have some data and your program needs specified input. For example strings which are numbers. You are searching for a way to transform the original data in a format you need. And the problem is: The source can be anything. It can be XML, property lists, binary which contains the needed data deeply embedded in binary junk. And your output format may vary also: It can be number strings, float, doubles.... You don't want to program. You want routines which gives you commands capable to transform the data in a form you wish. Surely it contains regular expressions, but it is very good designed and it offers capabilities which are sometimes much more easier and more powerful. Something like a super-grep which you can access (!) as program routines, not only as tool. It allows: joining/grouping/merging of results inserting/deleting/finding/replacing write macros which allows to execute a command chain repeatedly meta-grouping (lists-tables-hypertables) Example (No, I am not looking for a solution to this, it is just an example): You want to read xml strings embedded in a binary file with variable length records. Your tool reads the record length and deletes the junk surrounding your text. Now it splits open the xml and extracts the strings. Being Indian number glyphs and containing decimal commas instead of decimal points, your tool transforms it into ASCII and replaces commas with points. Now the results must be stored into matrices of variable length....etc. etc. I am searching for a good language / language-design and if possible, an implementation. Which design do you like or even, if it does not fulfill the conditions, wouldn't you want to miss ? EDIT: The question is if a solution for the problem exists and if yes, which implementations are available. You DO NOT implement your own sorting algorithm if Quicksort, Mergesort and Heapsort is available. You DO NOT invent your own text parsing method if you have regular expressions. You DO NOT invent your own 3D language for graphics if OpenGL/Direct3D is available. There are existing solutions or at least papers describing the problem and giving suggestions. And there are people who may have worked and experienced such problems and who can give ideas and suggestions. The idea that this problem is totally new and I should work out and implement it myself without background knowledge seems for me, I must admit, totally off the mark.

    Read the article

  • Recommendations for SMS gateways with API-support

    - by knorv
    I'm building a web application that needs to send notifications by SMS. What SMS gateway service providers with API support fulfill the following requirements: Reliable Global delivery - I will send globally with no specific region being sent to more than others Ideally cheap What are your recommendations? Why?

    Read the article

  • What are the worst examples of moral failure in the history of software engineering?

    - by Amanda S
    Many computer science curricula include a class or at least a lecture on disasters caused by software bugs, such as the Therac-25 incidents or Ariane 5 Flight 501. Indeed, Wikipedia has a list of software bugs with serious consequences, and a question on StackOverflow addresses some of them too. We study the failures of the past so that we don't repeat them, and I believe that rather than ignoring them or excusing them, it's important to look at these failures squarely and remind ourselves exactly how the mistakes made by people in our profession cost real money and real lives. By studying failures caused by uncaught bugs and bad process, we learn certain lessons about rigorous testing and accountability, and we make sure that our innocent mistakes are caught before they cause major problems. There are kinds of less innocent failure in software engineering, however, and I think it's just as important to study the serious consequences caused by programmers motivated by malice, greed, or just plain amorality. Thus we can learn about the ethical questions that arise in our profession, and how to respond when we are faced with them ourselves. Unfortunately, it's much harder to find lists of these failures--the only one I can come up with is that apocryphal "DOS ain't done 'til Lotus won't run" story. What are the worst examples of moral failure in the history of software engineering?

    Read the article

  • What are all the disadvantages of using files as a means of communicating between two processes?

    - by Manny
    I have legacy code which I need to improve for performance reasons. My application comprises of two executables that need to exchange certain information. In the legacy code, one exe writes to a file ( the file name is passed as an argument to exe) and the second executable first checks if such a file exists; if does not exist checks again and when it finds it, then goes on to read the contents of the file. This way information in transferred between the two executables. The way the code is structured, the second executable is successful on the first try itself. Now I have to clean this code up and was wondering what are the disadvantages of using files as a means of communication rather than some inter-process communication like pipes.Is opening and reading a file more expensive than pipes? Are there any other disadvantages? And how significant do you think would be the performance degradation. The legacy code is run on both windows and linux.

    Read the article

  • F#: how to find Cartesian power

    - by Nike
    I have a problem with writing a Cartesian power function. I found many examples about calculating Cartesian Product, but no one about Cartesian power. For example, [1;2] raised to power 3 = [ [1;1;1] ; [1;1;2] ; [1;2;1] ; [1;2;2] ; [2;1;1] ; [2;1;2] ; [2;2;1]; [2;2;2] ] I use following code to calculate Cartesian Product: let Cprod U V = let mutable res = [] for u in U do for v in V do res <- res @ [[u;v]] res And trying to calculate Cartesian power. I use following code to calculate Cartesian Product: let Cpower U n = let mutable V = U for i=0 to n-1 do V <- Dprod U V V Visual Studio said: Error The resulting type would be infinite when unifying ''a' and ''a list'. I will thankful for any help and links.

    Read the article

  • Sources for news about network security

    - by chris.nullptr
    I am a software developer that wants to stay up-to-date on network security news. What are some of the best sources online for not only keeping tabs on newly discovered security vulnerabilities that may affect projects I'm working on, but also best-practices when developing network software. Please keep in mind that I am looking for sources that cater to the software developer not IT administration.

    Read the article

  • Which languages are dynamically typed and compiled (and which are statically typed and interpreted)?

    - by Skilldrick
    In my reading on dynamic and static typing, I keep coming up against the assumption that statically typed languages are compiled, while dynamically typed languages are interpreted. I know that in general this is true, but I'm interested in the exceptions. I'd really like someone to not only give some examples of these exceptions, but try to explain why it was decided that these languages should work in this way.

    Read the article

  • C# Detect Localhost Port Usage

    - by ThaKidd
    In advance, thank you for your advice. I am currently working on a program which uses Putty to create a SSH connection with a server that uses local port forwarding to enable a client, running my software, to access the service behind the SSH server via localhost. IE: client:20100 - Internet - Remote SSH server exposed via router/firewall - Local Intranet - Intranet Web POP3 Server:110. Cmd Line: "putty -ssh -2 -P 22 -C -L 20100:intranteIP:110 -pw sshpassword sshusername@sshserver" Client would use putty to create a SSH connection with the SSH server specifying in the connection string that it would like to tie port 110 of the Intranet POP3 Server to port 20100 on the client system. Therefore the client would be able to open up a mail client to localhost:20100 and interact with the Internal POP3 server over the SSH tunnel. The above is a general description. I already know what I am trying to do will work without a problem so am not looking for debate on the above. The question is this...How can I ensure the local port (I cannot use dynamic ports, so it must be static) on localhost is not being used or listened to by any other application? I am currently executing this code in my C# app: private bool checkPort(int port) { try { //Create a socket on the current IPv4 address Socket TestSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); // Create an IP end point IPEndPoint localIP = new IPEndPoint(IPAddress.Parse("127.0.0.1"), port); // Bind that port TestSocket.Bind(localIP); // Cleanup TestSocket.Close(); return false; } catch (Exception e) { // Exception occurred. Port is already bound. return true; } } I am currently calling this function starting with a specific port in a for loop to get the 'false' return at the first available port. The first port I try is actually being listened to by uTorrent. The above code does not catch this and my connection fails. What is the best method to ensure a port is truly free? I do understand some other program may grab the port during/after I have tested it. I just need to find something that will ensure it is not currently in use AT ALL when the test is executed. If there is a way to truly reserve the localhost port during the test, I would love to hear about it.

    Read the article

  • sqlite no such table

    - by Graham B
    can anyone please help. I've seen many people with the same problem and looked at all suggestions but still cannot get this to work. I have tried to unistall the application and install again, I have tried to change the version number and start again. I've debugged the code and it does go into the onCreate function, but when I go to make a select query it says the users table does not exist. Any help would greatly be appreciated. Thanks guys DatabaseHandler Class public class DatabaseHandler extends SQLiteOpenHelper { // Variables protected static final int DATABASE_VERSION = 1; protected static final String DATABASE_NAME = "MyUser.db"; // Constructor public DatabaseHandler(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); } // Creating Tables @Override public void onCreate(SQLiteDatabase db) { // Create the Users table // NOTE: I have the column variables saved above String CREATE_USERS_TABLE = "CREATE TABLE IF NOT EXISTS Users(" + KEY_PRIMARY_ID + " " + INTEGER + " " + PRIMARY_KEY + " " + AUTO_INCREMENT + " " + NOT_NULL + "," + USERS_KEY_EMAIL + " " + NVARCHAR+"(1000)" + " " + UNIQUE + " " + NOT_NULL + "," + USERS_KEY_PIN + " " + NVARCHAR+"(10)" + " " + NOT_NULL + ")"; db.execSQL(CREATE_USERS_TABLE); } // Upgrading database @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { db.execSQL("DROP TABLE IF EXISTS Users"); onCreate(db); } UserDataSource class public class UserDataSource { private SQLiteDatabase db; private DatabaseHandler dbHandler; public UserDataSource(Context context) { dbHandler = new DatabaseHandler(context); } public void OpenWriteable() throws SQLException { db = dbHandler.getWritableDatabase(); } public void Close() { dbHandler.close(); } // Validate the user login with the username and password provided public void ValidateLogin(String username, String pin) throws CustomException { Cursor cursor = db.rawQuery( "select * from Users where " + DatabaseHandler.USERS_KEY_EMAIL + " = '" + username + "'" + " and " + DatabaseHandler.USERS_KEY_PIN + " = '" + pin + "'" , null); ........ } Then in the activity class, I'm calling UserDataSource uds = new UserDataSource (this); uds.OpenWriteable(); uds.ValidateLogin("name", "pin"); Any help would be great, thanks very much Graham The following is the attached log from the error report 11-23 17:47:46.414: I/SqliteDatabaseCpp(26717): sqlite returned: error code = 1, msg = no such table: Users, db=/data/data/prometric.myitemwriter/databases/MyUser.db 11-23 17:47:57.085: D/AndroidRuntime(26717): Shutting down VM 11-23 17:47:57.085: W/dalvikvm(26717): threadid=1: thread exiting with uncaught exception (group=0x40bec1f8) 11-23 17:47:57.171: D/dalvikvm(26717): GC_CONCURRENT freed 575K, 8% free 8649K/9351K, paused 2ms+6ms 11-23 17:47:57.179: E/AndroidRuntime(26717): FATAL EXCEPTION: main 11-23 17:47:57.179: E/AndroidRuntime(26717): java.lang.IllegalStateException: Could not execute method of the activity 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.view.View$1.onClick(View.java:3091) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.view.View.performClick(View.java:3558) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.view.View$PerformClick.run(View.java:14152) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.os.Handler.handleCallback(Handler.java:605) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.os.Handler.dispatchMessage(Handler.java:92) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.os.Looper.loop(Looper.java:137) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.app.ActivityThread.main(ActivityThread.java:4514) 11-23 17:47:57.179: E/AndroidRuntime(26717): at java.lang.reflect.Method.invokeNative(Native Method) 11-23 17:47:57.179: E/AndroidRuntime(26717): at java.lang.reflect.Method.invoke(Method.java:511) 11-23 17:47:57.179: E/AndroidRuntime(26717): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:790) 11-23 17:47:57.179: E/AndroidRuntime(26717): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:557) 11-23 17:47:57.179: E/AndroidRuntime(26717): at dalvik.system.NativeStart.main(Native Method) 11-23 17:47:57.179: E/AndroidRuntime(26717): Caused by: java.lang.reflect.InvocationTargetException 11-23 17:47:57.179: E/AndroidRuntime(26717): at java.lang.reflect.Method.invokeNative(Native Method) 11-23 17:47:57.179: E/AndroidRuntime(26717): at java.lang.reflect.Method.invoke(Method.java:511) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.view.View$1.onClick(View.java:3086) 11-23 17:47:57.179: E/AndroidRuntime(26717): ... 11 more 11-23 17:47:57.179: E/AndroidRuntime(26717): Caused by: android.database.sqlite.SQLiteException: no such table: Users: , while compiling: select * from Users where email = '' and pin = '' 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.database.sqlite.SQLiteCompiledSql.native_compile(Native Method) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.database.sqlite.SQLiteCompiledSql.<init>(SQLiteCompiledSql.java:68) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.database.sqlite.SQLiteProgram.compileSql(SQLiteProgram.java:143) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.database.sqlite.SQLiteProgram.compileAndbindAllArgs(SQLiteProgram.java:361) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:127) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:94) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.database.sqlite.SQLiteQuery.<init>(SQLiteQuery.java:53) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:47) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1685) 11-23 17:47:57.179: E/AndroidRuntime(26717): at android.database.sqlite.SQLiteDatabase.rawQuery(SQLiteDatabase.java:1659) 11-23 17:47:57.179: E/AndroidRuntime(26717): at projectname.database.UserDataSource.ValidateLogin(UserDataSource.java:73) 11-23 17:47:57.179: E/AndroidRuntime(26717): at projectname.LoginActivity.btn_login_Click(LoginActivity.java:47) 11-23 17:47:57.179: E/AndroidRuntime(26717): ... 14 more

    Read the article

  • US (Postal) ZIP codes: ZIP+4 vs. ZIP in web applications

    - by FreekOne
    Hi guys, I am currently writing a web application intended for US users that asks them to input their ZIP code and I just found out about the ZIP+4 code. Since I am not from the US and getting a user's correct ZIP code is important, I have no idea which format I should use. Could anyone (preferably from the US) please clarify what's the deal with the +4 digits and how important are they ? Is it safe to use only the plain 5-digit ZIP ? Thank you in advance !

    Read the article

  • TileGroup does not fill the container

    - by Luo Yong
    I put a TileGroup in a BorderContainer and set the width to 100%, but the content in the TileGroup did not fill the parent container, it leaves a big chunk of blank on the right part. The code is: <s:BorderContainer width="100%" height="100%"> <s:TileGroup width="100%" requestedColumnCount="2"> <s:Button> button1 </s:Button> <s:Button> button2 </s:Button> <s:Button> button3 </s:Button> </s:TileGroup> </s:BorderContainer> and the result is like this: http://i.minus.com/iN39P7Us4cBm1.png The width is already set to 100% but it does not work. Is there any way to make the TileGroup fill the container like GridLayout does in Java swing? http://www.java2s.com/Code/JavaImages/GridLayoutPane.PNG Thank you very much.

    Read the article

  • display records which exist in file2 but not in file1

    - by Phoenix
    log file1 contains records of customers(name,id,date) who visited yesterday log file2 contains records of customers(name,id,date) who visited today How would you display customers who visited yesterday but not today? Constraint is: Don't use auxiliary data structure because file contains millions of records. [So, no hashes] Is there a way to do this using Unix commands ??

    Read the article

  • my realtime network receiving time differs a lot, anyone can help?

    - by sguox002
    I wrote a program using tcpip sockets to send commands to a device and receive the data from the device. The data size would be around 200kB to 600KB. The computer is directly connected to the device using a 100MB network. I found that the sending packets always arrive at the computer at 100MB/s speed (I have debugging information on the unit and I also verified this using some network monitoring software), but the receiving time differs a lot from 40ms to 250ms, even if the size is the same (I have a receiving buffer about 700K and the receiving window of 8092 bytes and changing the window size does not change anything). The phenomena differs also on different computers, but on the same computer the problem is very stable. For example, receiving 300k bytes on computer a would be 40ms, but it may cost 200ms on another computer. I have disabled firewall, antivirus, all other network protocol except the TCP/IP. Any experts on this can give me some hints?

    Read the article

  • Good language to learn in order to build small websites

    - by mkoryak
    I want to start building websites and charging people for them! My problem is that the stack that know well does not lend itself to quick development, or cheap hosting. I am looking for languages that satisfy the following criteria: Fast to develop in Can find cheap hosting for it Bonus points if it can also be 'enterprisey'

    Read the article

  • Should I invest time in learning about OR\M or LINQ?

    - by Peter Smith
    I'm a .NET web developer primarily who occasionally writes console applications to mine data, cleanup tasks, etc. Most of what I do winds up involving a database which I currently design via sql server management studio, using stored procedures, and query analyzer. I also create a lot of web services which are consumed via AJAX applications. Do these technologies really help you in speeding up development times? Do you still have to build the database or object code first?

    Read the article

  • Math/numerical formula every computer programmer should know

    - by aaa
    This is a follow-up question to What should every programmer know and Is mathematics necessary. So the question is, as a computer programmer, what is the most important/useful mathematical or numerical formula that you use? By Formula I mean anything that involves less obvious manipulations, whenever binomial coefficients or bit hacks. I work with multidimensional arrays and various matrix representations. So for me most commonly used formulas are: A(i,j,k,..) = a[i + j*Dim0 + k*Dim0*Dim1 + ... to map indexes to one dimension ( which is basic address calculation which many people do not seem to know). And triangular number T(i) = (i*i + i)/2 which is related to binomial coefficients, used to calculate address in triangular matrixes and many other things. What is your workhorse formula that you think programmer should know?

    Read the article

  • (For what) Are Fortran, Cobol and Co. used today?

    - by lamas
    I'm a relatively young programmer and so I don't really know much about languages like Fortran or Cobol that have their origins in the beginning of modern informatics. I'm a bit confused because it seems like there are many people out there saying that these two languages are still very alive and being used all over the world whereas others say the opposite. In addition, it seems like there are only very few questions tagged Fortran or Cobol here on stackoverflow. Can someone "demystify" the situation for me? Who uses these senior languages these days and are they even used anymore? Do you have any experiences with one of the languages or do you know something about their latest developments?

    Read the article

  • Naming convention in Objective C /C , start with "_"?

    - by Tattat
    Something I see ppl define the variable like this: b2World *_world; b2Body *_body; CCSprite *_ball; instead of b2World *world; b2Body *body; CCSprite *ball; I familiar with the second one, but not the first one. So, I checked the Wikipedia about naming convention: Names beginning with double underscore or an underscore and a capital letter are reserved for implementation (compiler, standard library) and should not be used (e.g. __reserved or _Reserved). So, is that any special meaning which is start with "_"? The wiki page.

    Read the article

< Previous Page | 243 244 245 246 247 248 249 250 251 252 253 254  | Next Page >