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  • EF Code First to SQL Azure

    - by Predrag Pejic
    I am using EF Code First to create a database on local .\SQLEXPRESS. Among others. I have these 2 classes: public class Shop { public int ShopID { get; set; } [Required(AllowEmptyStrings = false, ErrorMessage = "You must enter a name!")] [MaxLength(25, ErrorMessage = "Name must be 25 characters or less")] public string Name { get; set; } [Required(AllowEmptyStrings = false, ErrorMessage = "You must enter an address!")] [MaxLength(30, ErrorMessage = "Address must be 30 characters or less")] public string Address { get; set; } [Required(AllowEmptyStrings = false, ErrorMessage = "You must enter a valid city name!")] [MaxLength(30, ErrorMessage = "City name must be 30 characters or less")] public string City { get; set; } [Required(AllowEmptyStrings = false, ErrorMessage = "You must enter a phone number!")] [MaxLength(14, ErrorMessage = "Phone number must be 14 characters or less")] public string Phone { get; set; } [MaxLength(100, ErrorMessage = "Description must be 50 characters or less")] public string Description { get; set; } [Required(AllowEmptyStrings = false, ErrorMessage = "You must enter a WorkTime!")] public DateTime WorkTimeBegin { get; set; } [Required(AllowEmptyStrings = false, ErrorMessage = "You must enter a WorkTime!")] public DateTime WorkTimeEnd { get; set; } public DateTime? SaturdayWorkTimeBegin { get; set; } public DateTime? SaturdayWorkTimeEnd { get; set; } public DateTime? SundayWorkTimeBegin { get; set; } public DateTime? SundayWorkTimeEnd { get; set; } public int ShoppingPlaceID { get; set; } public virtual ShoppingPlace ShoppingPlace { get; set; } public virtual ICollection<Category> Categories { get; set; } } public class ShoppingPlace { [Key] public int ShopingplaceID { get; set; } [Required(AllowEmptyStrings = false, ErrorMessage = "You must enter a name!")] [MaxLength(25, ErrorMessage = "Name must be 25 characters or less")] public string Name { get; set; } [Required(AllowEmptyStrings = false, ErrorMessage = "You must enter an address!")] [MaxLength(50, ErrorMessage = "Address must be 50 characters or less")] public string Address { get; set; } [Required(AllowEmptyStrings = false, ErrorMessage = "You must enter a city name!")] [MaxLength(30, ErrorMessage = "City must be 30 characters or less")] public string City { get; set; } [Required(AllowEmptyStrings = false, ErrorMessage = "You must enter a valid phone number!")] [MaxLength(14, ErrorMessage = "Phone number must be 14 characters or less")] public string Phone { get; set; } public int ShoppingCenterID { get; set; } public virtual ShoppingCenter ShoppingCenter { get; set; } public virtual ICollection<Shop> Shops { get; set; } } and a method in DbContext: modelBuilder.Entity<Item>() .HasRequired(p => p.Category) .WithMany(a => a.Items) .HasForeignKey(a => a.CategoryID) .WillCascadeOnDelete(false); modelBuilder.Entity<Category>() .HasRequired(a => a.Shop) .WithMany(a => a.Categories) .HasForeignKey(a => a.ShopID) .WillCascadeOnDelete(false); modelBuilder.Entity<Shop>() .HasOptional(a => a.ShoppingPlace) .WithMany(a => a.Shops) .HasForeignKey(a => a.ShoppingPlaceID) .WillCascadeOnDelete(false); modelBuilder.Entity<ShoppingPlace>() .HasOptional(a => a.ShoppingCenter) .WithMany(a => a.ShoppingPlaces) .HasForeignKey(a => a.ShoppingCenterID) .WillCascadeOnDelete(false); Why I can't create Shop without creating and populating ShopingPlace. How to achieve that? EDIT: Tried with: modelBuilder.Entity<Shop>() .HasOptional(a => a.ShoppingPlace) .WithOptionalPrincipal(); modelBuilder.Entity<ShoppingPlace>() .HasOptional(a => a.ShoppingCenter) .WithOptionalPrincipal(); and it passed, but what is the difference? And why in SQL Server i am allowed to see ShoppingPlaceID and ShoppingPlace_ShopingPlaceID when in the case of Item and Category i see only one?

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  • Fastest gap sequence for shell sort ?

    - by Tony
    According to Marcin Ciura's Optimal (best known) sequence of increments for shell sort algorithm. The best sequence for shellsort is 1, 4, 10, 23, 57, 132, 301, 701... But how can I generate such a sequence ? In Marcin Ciura's paper he said : Both Knuth’s and Hibbard’s sequences are relatively bad, because they are defined by simple linear recurrences but most algorithm books I searched , they all tend to use Knuth’s sequence : k = 3k + 1 ; because it's easy to generate , what's your way of generating shellsort sequence ?

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  • learning inkscape for webapp/website

    - by creativz
    Hello, I'm quite impressed with Incskape, it's very powerfull. That's why I wanted to start learning it. But how should I start (to learn it efficiently)? Should I read a book (anybody can recommend me a good one?) or just (inefficiently) do some tutorials on the internet. I really want to learn it to make professional graphics for a webapp or website. So how should I tackle it? Thanks!

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  • Update data programmatically using EntityDataSource

    - by Vinay
    Hello guys, I want to update the data using programmatically in code behind using EntityDataSource. I have done the samething using Update method of LINQ Datasource. sample code snippet int id = Convert.ToInt32(e.CommandArgument); ListDictionary keyValues = new ListDictionary(); ListDictionary newValues = new ListDictionary(); ListDictionary oldValues = new ListDictionary(); keyValues.Add("ReviewID", id); oldValues.Add("IsActive", "IsActive"); newValues.Add("IsActive", "false"); GridDataSource.Update(keyValues,newValues, oldValues); Can I achieve the same thing using EntityDataSource? Thanks, Vinay

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  • Using Zend_HTTP_Client instead of CURL

    - by Vincent
    All, I want to use Zend_HTTP_CLient instead of CURL as there are issues with using curl on Solaris. I have the following curl code.. How will this code be written if I want to use Zend_HTTP_Client? $ch = curl_init(); $devnull = fopen('/tmp/cookie.txt', 'w'); curl_setopt($ch, CURLOPT_STDERR, $devnull); curl_setopt($ch, CURLOPT_POST, 1); curl_setopt($ch, CURLOPT_URL, $desturl); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false); curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false); curl_setopt($ch, CURLOPT_HEADER, false); curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 0); curl_setopt($ch, CURLOPT_CONNECTTIMEOUT,800); curl_setopt($ch, CURLOPT_AUTOREFERER, true); curl_setopt($ch, CURLOPT_ENCODING, 'gzip,deflate'); curl_setopt($ch, CURLOPT_POSTFIELDS, $postdata); $retVal = curl_exec($ch); print_r(curl_error($ch)); curl_close($ch); if ($devnull) { fclose($devnull); } Thanks

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  • Modifying a column with the 'Identity' pattern is not supported in WCF RIA Services

    - by Banford
    I've been following the walkthrough for creating your first WCF RIA Services Application from Microsoft and have encountered a problem when trying to edit and update data using the SubmitChanges() method of the Data Context. The table being updated has an Identity Specification set in SQL Server 2008 on the 'CourseID' column. However the PRIMARY key is a composite of two other fields. When using SubmitChanges() the application locks up in the browser an presents an unhandled exception. By handling this exception I managed to get the message: Modifying a column with the 'Identity' pattern is not supported. This is referring to the 'CourseID' column. Turning identity specification off solves the problem, but I need the auto-incrementing ID. In what way isn't this supported. Or where am I going wrong?

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  • Help:Graph contest problem: maybe a modified Dijkstra or another alternative algorithm

    - by newba
    Hi you all, I'm trying to do this contest exercise about graphs: XPTO is an intrepid adventurer (a little too temerarious for his own good) who boasts about exploring every corner of the universe, no matter how inhospitable. In fact, he doesn't visit the planets where people can easily live in, he prefers those where only a madman would go with a very good reason (several millions of credits for instance). His latest exploit is trying to survive in Proxima III. The problem is that Proxima III suffers from storms of highly corrosive acids that destroy everything, including spacesuits that were especially designed to withstand corrosion. Our intrepid explorer was caught in a rectangular area in the middle of one of these storms. Fortunately, he has an instrument that is capable of measuring the exact concentration of acid on each sector and how much damage it does to his spacesuit. Now, he only needs to find out if he can escape the storm. Problem The problem consists of finding an escape route that will allow XPTOto escape the noxious storm. You are given the initial energy of the spacesuit, the size of the rectangular area and the damage that the spacesuit will suffer while standing in each sector. Your task is to find the exit sector, the number of steps necessary to reach it and the amount of energy his suit will have when he leaves the rectangular area. The escape route chosen should be the safest one (i.e., the one where his spacesuit will be the least damaged). Notice that Rodericus will perish if the energy of his suit reaches zero. In case there are more than one possible solutions, choose the one that uses the least number of steps. If there are at least two sectors with the same number of steps (X1, Y1) and (X2, Y2) then choose the first if X1 < X2 or if X1 = X2 and Y1 < Y2. Constraints 0 < E = 30000 the suit's starting energy 0 = W = 500 the rectangle's width 0 = H = 500 rectangle's height 0 < X < W the starting X position 0 < Y < H the starting Y position 0 = D = 10000 the damage sustained in each sector Input The first number given is the number of test cases. Each case will consist of a line with the integers E, X and Y. The following line will have the integers W and H. The following lines will hold the matrix containing the damage D the spacesuit will suffer whilst in the corresponding sector. Notice that, as is often the case for computer geeks, (1,1) corresponds to the upper left corner. Output If there is a solution, the output will be the remaining energy, the exit sector's X and Y coordinates and the number of steps of the route that will lead Rodericus to safety. In case there is no solution, the phrase Goodbye cruel world! will be written. Sample Input 3 40 3 3 7 8 12 11 12 11 3 12 12 12 11 11 12 2 1 13 11 11 12 2 13 2 14 10 11 13 3 2 1 12 10 11 13 13 11 12 13 12 12 11 13 11 13 12 13 12 12 11 11 11 11 13 13 10 10 13 11 12 8 3 4 7 6 4 3 3 2 2 3 2 2 5 2 2 2 3 3 2 1 2 2 3 2 2 4 3 3 2 2 4 1 3 1 4 3 2 3 1 2 2 3 3 0 3 4 10 3 4 7 6 3 3 1 2 2 1 0 2 2 2 4 2 2 5 2 2 1 3 0 2 2 2 2 1 3 3 4 2 3 4 4 3 1 1 3 1 2 2 4 2 2 1 Sample Output 12 5 1 8 Goodbye cruel world! 5 1 4 2 Basically, I think we have to do a modified Dijkstra, in which the distance between nodes is the suit's energy (and we have to subtract it instead of suming up like is normal with distances) and the steps are the ....steps made along the path. The pos with the bester binomial (Energy,num_Steps) is our "way out". Important : XPTO obviously can't move in diagonals, so we have to cut out this cases. I have many ideas, but I have such a problem implementing them... Could someone please help me thinking about this with some code or, at least, ideas? Am I totally wrong?

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  • spring 3 AOP anotated advises

    - by Art79
    Trying to figure out how to Proxy my beans with AOP advices in annotated way. I have a simple class @Service public class RestSampleDao { @MonitorTimer public Collection<User> getUsers(){ .... return users; } } i have created custom annotation for monitoring execution time @Target({ ElementType.METHOD, ElementType.TYPE }) @Retention(RetentionPolicy.RUNTIME) public @interface MonitorTimer { } and advise to do some fake monitoring public class MonitorTimerAdvice implements MethodInterceptor { public Object invoke(MethodInvocation invocation) throws Throwable{ try { long start = System.currentTimeMillis(); Object retVal = invocation.proceed(); long end = System.currentTimeMillis(); long differenceMs = end - start; System.out.println("\ncall took " + differenceMs + " ms "); return retVal; } catch(Throwable t){ System.out.println("\nerror occured"); throw t; } } } now i can use it if i manually proxy the instance of dao like this AnnotationMatchingPointcut pc = new AnnotationMatchingPointcut(null, MonitorTimer.class); Advisor advisor = new DefaultPointcutAdvisor(pc, new MonitorTimerAdvice()); ProxyFactory pf = new ProxyFactory(); pf.setTarget( sampleDao ); pf.addAdvisor(advisor); RestSampleDao proxy = (RestSampleDao) pf.getProxy(); mv.addObject( proxy.getUsers() ); but how do i set it up in Spring so that my custom annotated methods would get proxied by this interceptor automatically? i would like to inject proxied samepleDao instead of real one. Can that be done without xml configurations? i think should be possible to just annotate methods i want to intercept and spring DI would proxy what is necessary. or do i have to use aspectj for that? would prefere simplest solution :- ) thanks a lot for help!

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  • Using C# and Repository Factory and the error: The requested database is not defined in configurati

    - by odiseh
    hi I am using Repository factory for visual studio 2008 for a personal project. It generated a class called ProductRepository which inherits from Repository. The ProductRepository has a constructor which gets a database name as string and passes it to its base (I mean Repository ). So when I try to debug my project step by step, I pass my database name to ProductRepository but it raises the following error: The requested database is not defined in configuration. What's wrong?

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  • Resizing and saving an image in WinMobile and .NET CF throws OutOfMemoryException

    - by devguy
    I have a WinMobile app which allows the user the snap a photo with the camera, and then use for for various things. The photo can be snapped at 1600x1200, 800x600 or 640x480, but it must always be resized to 400px for the longest size (the other is proportional of course). Here's the code: private void LoadImage(string path) { Image tmpPhoto = new Bitmap(path); // calculate new bitmap size... double width = ... double height = ... // draw new bitmap Image photo = new Bitmap(width, height, System.Drawing.Imaging.PixelFormat.Format24bppRgb); using (Graphics g = Graphics.FromImage(photo)) { g.FillRectangle(new SolidBrush(Color.White), new Rectangle(0, 0, photo.Width, photo.Height)); int srcX = (int)((double)(tmpPhoto.Width - width) / 2d); int srcY = (int)((double)(tmpPhoto.Height - height) / 2d); g.DrawImage(tmpPhoto, new Rectangle(0, 0, photo.Width, photo.Height), new Rectangle(srcX, srcY, photo.Width, photo.Height), GraphicsUnit.Pixel); } tmpPhoto.Dispose(); // save new image and dispose photo.Save(Path.Combine(config.TempPath, config.TempPhotoFileName), System.Drawing.Imaging.ImageFormat.Jpeg); photo.Dispose(); } Now the problem is that the app breaks in the photo.Save call, with an OutOfMemoryException. And I don't know why, since I dispose the tempPhoto (with the original photo from the camera) as soon as I can, and I also dispose the Graphics obj. Why does this happen? It seems impossible to me that one can't take a photo with the camera and resize/save it without making it crash :( Should I restor t C++ for such a simple thing? Thanks.

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  • Notification CeSetUserNotificationEx with custom sound

    - by inTagger
    Hail all! I want to display notification and play custom sound on my Windows Mobile 5/6 device. I have tried something like that, but my custom sound does not play, though message is displayed with standart sound. If i edit Wave key in [HKEY_CURRENT_USER\ControlPanel\Notifications{15F11F90-8A5F-454c-89FC-BA9B7AAB0CAD}] to sound file i need then it plays okay. But why there are flag NotificationAction.Sound and property UserNotification.Sound? It doesn't work. Also Vibration and Led don't work, if i use such flags. (You can obtain full project sources from http://dl.dropbox.com/u/1758206/Code/Thunder.zip) var trigger = new UserNotificationTrigger { StartTime = DateTime.Now + TimeSpan.FromSeconds(1), Type = NotificationType.ClassicTime }; var userNotification = new UserNotification { Sound = @"\Windows\Alarm1.wma", Text = "Hail from Penza, Russia!", Action = NotificationAction.Dialog | NotificationAction.Sound, Title = string.Empty, MaxSound = 16384 }; NotificationTools.SetUserNotification(0, trigger, userNotification); UserNotificationTrigger.cs: using System; using System.Runtime.InteropServices; namespace Thunder.Lib.ThunderMethod1 { /// <summary> /// Specifies the type of notification. /// </summary> public enum NotificationType { /// <summary> /// Equivalent to using the SetUserNotification function. /// The standard command line is supplied. /// </summary> ClassicTime = 4, /// <summary> /// System event notification. /// </summary> Event = 1, /// <summary> /// Time-based notification that is active for the time period between StartTime and EndTime. /// </summary> Period = 3, /// <summary> /// Time-based notification. /// </summary> Time = 2 } /// <summary> /// System Event Flags /// </summary> public enum NotificationEvent { None, TimeChange, SyncEnd, OnACPower, OffACPower, NetConnect, NetDisconnect, DeviceChange, IRDiscovered, RS232Detected, RestoreEnd, Wakeup, TimeZoneChange, MachineNameChange, RndisFNDetected, InternetProxyChange } /// <summary> /// Defines what event activates a notification. /// </summary> [StructLayout(LayoutKind.Sequential)] public class UserNotificationTrigger { internal int dwSize = 52; private int dwType; private int dwEvent; [MarshalAs(UnmanagedType.LPWStr)] private string lpszApplication = string.Empty; [MarshalAs(UnmanagedType.LPWStr)] private string lpszArguments; internal SYSTEMTIME stStartTime; internal SYSTEMTIME stEndTime; /// <summary> /// Specifies the type of notification. /// </summary> public NotificationType Type { get { return (NotificationType) dwType; } set { dwType = (int) value; } } /// <summary> /// Specifies the type of event should Type = Event. /// </summary> public NotificationEvent Event { get { return (NotificationEvent) dwEvent; } set { dwEvent = (int) value; } } /// <summary> /// Name of the application to execute. /// </summary> public string Application { get { return lpszApplication; } set { lpszApplication = value; } } /// <summary> /// Command line (without the application name). /// </summary> public string Arguments { get { return lpszArguments; } set { lpszArguments = value; } } /// <summary> /// Specifies the beginning of the notification period. /// </summary> public DateTime StartTime { get { return stStartTime.ToDateTime(); } set { stStartTime = SYSTEMTIME.FromDateTime(value); } } /// <summary> /// Specifies the end of the notification period. /// </summary> public DateTime EndTime { get { return stEndTime.ToDateTime(); } set { stEndTime = SYSTEMTIME.FromDateTime(value); } } } } UserNotification.cs: using System.Runtime.InteropServices; namespace Thunder.Lib.ThunderMethod1 { /// <summary> /// Contains information used for a user notification. /// </summary> [StructLayout(LayoutKind.Sequential)] public class UserNotification { private int ActionFlags; [MarshalAs(UnmanagedType.LPWStr)] private string pwszDialogTitle; [MarshalAs(UnmanagedType.LPWStr)] private string pwszDialogText; [MarshalAs(UnmanagedType.LPWStr)] private string pwszSound; private int nMaxSound; private int dwReserved; /// <summary> /// Any combination of the <see cref="T:Thunder.Lib.NotificationAction" /> members. /// </summary> /// <value>Flags which specifies the action(s) to be taken when the notification is triggered.</value> /// <remarks>Flags not valid on a given hardware platform will be ignored.</remarks> public NotificationAction Action { get { return (NotificationAction) ActionFlags; } set { ActionFlags = (int) value; } } /// <summary> /// Required if NotificationAction.Dialog is set, ignored otherwise /// </summary> public string Title { get { return pwszDialogTitle; } set { pwszDialogTitle = value; } } /// <summary> /// Required if NotificationAction.Dialog is set, ignored otherwise. /// </summary> public string Text { get { return pwszDialogText; } set { pwszDialogText = value; } } /// <summary> /// Sound string as supplied to PlaySound. /// </summary> public string Sound { get { return pwszSound; } set { pwszSound = value; } } public int MaxSound { get { return nMaxSound; } set { nMaxSound = value; } } } } NativeMethods.cs: using System; using System.Runtime.InteropServices; namespace Thunder.Lib.ThunderMethod1 { [StructLayout(LayoutKind.Sequential)] public struct SYSTEMTIME { public short wYear; public short wMonth; public short wDayOfWeek; public short wDay; public short wHour; public short wMinute; public short wSecond; public short wMillisecond; public static SYSTEMTIME FromDateTime(DateTime dt) { return new SYSTEMTIME { wYear = (short) dt.Year, wMonth = (short) dt.Month, wDayOfWeek = (short) dt.DayOfWeek, wDay = (short) dt.Day, wHour = (short) dt.Hour, wMinute = (short) dt.Minute, wSecond = (short) dt.Second, wMillisecond = (short) dt.Millisecond }; } public DateTime ToDateTime() { if ((((wYear == 0) && (wMonth == 0)) && ((wDay == 0) && (wHour == 0))) && ((wMinute == 0) && (wSecond == 0))) return DateTime.MinValue; return new DateTime(wYear, wMonth, wDay, wHour, wMinute, wSecond, wMillisecond); } } /// <summary> /// Specifies the action to take when a notification event occurs. /// </summary> [Flags] public enum NotificationAction { /// <summary> /// Displays the user notification dialog box. /// </summary> Dialog = 4, /// <summary> /// Flashes the LED. /// </summary> Led = 1, /// <summary> /// Dialog box z-order flag. /// Set if the notification dialog box should come up behind the password. /// </summary> Private = 32, /// <summary> /// Repeats the sound for 10–15 seconds. /// </summary> Repeat = 16, /// <summary> /// Plays the sound specified. /// </summary> Sound = 8, /// <summary> /// Vibrates the device. /// </summary> Vibrate = 2 } internal class NativeMethods { [DllImport("coredll.dll", CallingConvention = CallingConvention.Winapi, CharSet = CharSet.Unicode, SetLastError = true)] internal static extern int CeSetUserNotificationEx(int hNotification, UserNotificationTrigger lpTrigger, UserNotification lpUserNotification); } } NotificationTools.cs: using System.ComponentModel; using System.Runtime.InteropServices; namespace Thunder.Lib.ThunderMethod1 { public static class NotificationTools { /// <summary> /// This function modifies an existing user notification. /// </summary> /// <param name="handle">Handle of the Notification to be modified</param> /// <param name="trigger">A UserNotificationTrigger that defines what event activates a notification.</param> /// <param name="notification">A UserNotification that defines how the system should respond when a notification occurs.</param> /// <returns>Handle to the notification event if successful.</returns> public static int SetUserNotification(int handle, UserNotificationTrigger trigger, UserNotification notification) { int num = NativeMethods.CeSetUserNotificationEx(handle, trigger, notification); if (num == 0) throw new Win32Exception(Marshal.GetLastWin32Error(), "Error setting UserNotification"); return num; } } }

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  • VS2008 EF and non crud SP usage.

    - by SteveO
    Using an edmx version of EF. My returned data is a join between tables that has a COMPOUND filter on the primary table. In essence this query is going to return a SEGMENT of Law codes and descriptions that a user can tie to a Sex Offender report. I have a complex SP because Linq2SQL cannot pass in a between statement, or at least that is how I understand the error. The Code itself is broken up by '-' marks. 39-13-504 "Aggravated Sexual Battery" User wants to have a query with 4 parmas 39, 13, 500, 599. Get all codes from Title 39 and Chapter 13 with parts between 500 and 599. I have the SP in place to do the work, is there are way to consume the SP within the EF? I find many blogs about SPs with CRUD operations as their use of an SP. That doesn't fit this need at all. I do not have a single table but a join to the "prior selections" table that maps the key for the code. Any pointers on how to get a READ with an SP? TIA

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  • Dealing with the lack of closures in Objective-C

    - by Sean Clark Hess
    Maybe it's just the fact that I've been using http://nodejs.org/ lately, but the lack of closures in Objective-C (iphone) has been really hard to work around. For example, I'm creating service classes. Each service class can have several methods, each of which makes a different URL request. I can use the delegate pattern, but that means that I have to create a new service each time I want to call a method on it (because it has to store the delegate and selector for that request, and new method calls would overwrite them). Even more difficult for me is the fact that I can't easily keep local variables around in the scope for a callback. I have to store anything I want to send back to the delegate on the service class itself, which makes it harder to have more than one method on each class. How do you pros do it? Should I just quit whining and do it another way?

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  • Difference between Singleton implemention using pointer and using static object

    - by Anon
    EDIT: Sorry my question was not clear, why do books/articles prefer implementation#1 over implementation#2? What is the actual advantage of using pointer in implementation of Singleton class vs using a static object? Why do most books prefer this class Singleton { private: static Singleton *p_inst; Singleton(); public: static Singleton * instance() { if (!p_inst) { p_inst = new Singleton(); } return p_inst; } }; over this class Singleton { public: static Singleton& Instance() { static Singleton inst; return inst; } protected: Singleton(); // Prevent construction Singleton(const Singleton&); // Prevent construction by copying Singleton& operator=(const Singleton&); // Prevent assignment ~Singleton(); // Prevent unwanted destruction };

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  • Visitor pattern and compiler code generation, how to get children attributes?

    - by LeleDumbo
    I'd like to modify my compiler's code generator to use visitor pattern since the current approach must use multiple conditional statement to check the real type of a child before generating the corresponding code. However, I have problems to get children attributes after they're visited. For instance, in binary expression I use this: LHSCode := GenerateExpressionCode(LHSNode); RHSCode := GenerateExpressionCode(RHSNode); CreateBinaryExpression(Self,LHS,RHS); In visitor pattern the visit method is usually void, so I can't get the expression code from LHS and RHS. Keeping shared global variables isn't an option since expression code generation is recursive thus could erase previous values kept in the variables. I'll just show the binary expression as this is the most complicated part (for now): function TLLVMCodeGenerator.GenerateExpressionCode( Expr: TASTExpression): TLLVMValue; var BinExpr: TASTBinaryExpression; UnExpr: TASTUnaryExpression; LHSCode, RHSCode, ExprCode: TLLVMValue; VarExpr: TASTVariableExpression; begin if Expr is TASTBinaryExpression then begin BinExpr := Expr as TASTBinaryExpression; LHSCode := GenerateExpressionCode(BinExpr.LHS); RHSCode := GenerateExpressionCode(BinExpr.RHS); case BinExpr.Op of '<': Result := FBuilder.CreateICmp(ccSLT, LHSCode, RHSCode); '<=': Result := FBuilder.CreateICmp(ccSLE, LHSCode, RHSCode); '>': Result := FBuilder.CreateICmp(ccSGT, LHSCode, RHSCode); '>=': Result := FBuilder.CreateICmp(ccSGE, LHSCode, RHSCode); '==': Result := FBuilder.CreateICmp(ccEQ, LHSCode, RHSCode); '<>': Result := FBuilder.CreateICmp(ccNE, LHSCode, RHSCode); '/\': Result := FBuilder.CreateAnd(LHSCode, RHSCode); '\/': Result := FBuilder.CreateOr(LHSCode, RHSCode); '+': Result := FBuilder.CreateAdd(LHSCode, RHSCode); '-': Result := FBuilder.CreateSub(LHSCode, RHSCode); '*': Result := FBuilder.CreateMul(LHSCode, RHSCode); '/': Result := FBuilder.CreateSDiv(LHSCode, RHSCode); end; end else if Expr is TASTPrimaryExpression then if Expr is TASTBooleanConstant then with Expr as TASTBooleanConstant do Result := FBuilder.CreateConstant(Ord(Value), ltI1) else if Expr is TASTIntegerConstant then with Expr as TASTIntegerConstant do Result := FBuilder.CreateConstant(Value, ltI32) else if Expr is TASTUnaryExpression then begin UnExpr := Expr as TASTUnaryExpression; ExprCode := GenerateExpressionCode(UnExpr.Expr); case UnExpr.Op of '~': Result := FBuilder.CreateXor( FBuilder.CreateConstant(1, ltI1), ExprCode); '-': Result := FBuilder.CreateSub( FBuilder.CreateConstant(0, ltI32), ExprCode); end; end else if Expr is TASTVariableExpression then begin VarExpr := Expr as TASTVariableExpression; with VarExpr.VarDecl do Result := FBuilder.CreateVar(Ident, BaseTypeLLVMTypeMap[BaseType]); end; end; Hope you understand it :)

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  • Graphical sandbox for pathfinding

    - by vrode
    If you needed a clean and consistent sandbox for pathfinding what would you use? I want to experiment with different pathfinding algorithms by sending virtual units (robots) around obstacles on a geometric plane. But I don't need a feature overkill like a game engine or Flash might have, just an animated report and native collision detector. I prefer it to be scripted in python, but if there are java or C++ alternatives I would appreciate them as well.

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  • Tree data structure in iphone with coredata

    - by ebabchick
    Hi, I am looking to store a tree structure in CoreData for iphone. Can someone give me some tips on the best way to go about this? Basically I want to have a bunch of folders that people can dive into in a table view, and I want to have leaves of the tree be photos. The thing is, I want to be able to let the user edit these folders on-the-fly and add folders and content (photos) at their discretion. I'm relatively new to CoreData. Any help would be appreciated. Thanks.

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  • Is this the correct way of speaking to a "Content Manager" Class?

    - by DeanMc
    I am creating a silverlight site. I am currently breaking out my ideas into pieces of functionality. One of the idea's I have is the concept of a content manager. This is essentially a UI control with 4 regions. Top, Bottom, Right & Left. I also have a collection of objects that are considered "Menu Items". These are controls that function as a way to navigate around, similar to links. The idea I have is to implement an IMenuItem interface. Among the standard pieces of information (Text, PageReference, etc) I was also going to hold a reference to the content manager. My idea behind this thinking is that I can pass the PageReference to a property on the ContentManager and then call a method which knows how to update the content manager accordingly. Is this the best way of implementing this or is their some sort of pattern for it?

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  • Invoice Discount: Negative line items vs Internal properties

    - by FreshCode
    Should discount on invoice items and entire invoices be negative line items or separate properties of an invoice? In a similar question, Should I incorporate list of fees/discounts into an order class or have them be itemlines, the asker focuses more on orders than invoices (which is a slightly different business entity). Discount is proposed to be separate from order items since it is not equivalent to a fee or product and may have different reporting requirements. Hence, discount should not simply be a negative line item. Previously I have successfully used negative line items to clearly indicate and calculate discount, but this feels inflexible and inaccurate from a business perspective. Now I am opting to add discount to each line item, along with an invoice-wide discount. Is this the right way to do it? Should each item have its own discount amount and percentage? Domain Model Code Sample This is what my domain model, which maps to an SQL repository, looks like: public class Invoice { public int ID { get; set; } public Guid JobID { get; set; } public string InvoiceNumber { get; set; } public Guid UserId { get; set; } // user who created it public DateTime Date { get; set; } public decimal DiscountPercent { get; set; } // all lines discount %? public decimal DiscountAmount { get; set; } // all lines discount $? public LazyList<InvoiceLine> InvoiceLines { get; set; } public LazyList<Payment> Payments { get; set; } // for payments received public boolean IsVoided { get; set; } // Invoices are immutable. // To change: void -> new invoice. public decimal Total { get { return (1.0M - DiscountPercent) * InvoiceLines.Sum(i => i.LineTotal) - DiscountAmount; } } } public class InvoiceLine { public int ID { get; set; } public int InvoiceID { get; set; } public string Title { get; set; } public decimal Quantity { get; set; } public decimal LineItemPrice { get; set; } public decimal DiscountPercent { get; set; } // line discount %? public decimal DiscountAmount { get; set; } // line discount amount? public decimal LineTotal { get { return (1.0M - DiscountPercent) * (this.Quantity * (this.LineItemPrice)) - DiscountAmount; } } }

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  • Database change management tools?

    - by zodeus
    We are currently in the process of solidifying a database change management process. We run MySql 5 running on RedHat 5. I have selected LiquiBase as the tool because it's open source and allows us to expand its functionality later if needed. It also seems to be one of the few free projects that are still active. Has anyone here had any experience using LiquiBase or other Db versioning tools? Company Background: We are an SaaS company providing a 7/24 hosted application. There are dozens of instances running different versions of the same database and we need a way to manage the deploy process as it's starting to get out of control. The databases have hundreds of tables and we typically do releases once every 3 months.

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  • Diagramming Software for a Developer/Designer

    - by Craig Walker
    For a long time I've been looking for a good diagramming/vector-based drawing program that meets my needs as a developer. I'd like to: Draw database diagrams Draw flow charts Draw object-modeling diagrams (UML being the standard) Draw other free-form diagrams (basically boxes & arrows with the occasional clipart) Draw mockups of user interfaces and web pages EDIT: I want good-looking electronic-format diagrams that I can show to 3rd parties, not just something for my own internal use. EDIT 2: I'm also looking for Windows software, although I'm toying with the idea of switching to Mac, so a really good Mac-only product might get me to switch. Basically I need a good vector graphic program (with decent grouping, connecting lines, and ideally auto-routing). I'd prefer a diagramming tool that can also be used for drawing (for the UI mockups) rather than a drawing tool that can also be used for diagrams. I've tried Visio on several occasions, and every time I've been disappointed. The interface always seems to get in my way at some point. It's pretty close to what I want, and the latest version (I got the trail from MS) seems to be better than previous ones in terms of usability, but I really don't want to plunk down that sort of cash for a mediocre product. I've tried Dia and Inkscape, and while initially promising and with the right price tag, I found both of them to be lacking in several ways (including some recurring bugs). I've toyed with getting Adobe Illustrator, but I've never used it before, and I have a feeling that it wouldn't handle the diagramming aspect very well, and I don't want to buy a copy just to find out it doesn't meet my needs. So far, the product that I've had the most success with is, sadly, OpenOffice Draw. It's free of course (which lowers my expectations and thus improves my view of it) and its usability is pretty good, but in the end I'd like something more suited to diagramming. I'm willing to spend real money (in the $500-$1K range) for a really good piece of software if it does everything I want it to. The front runner is of course Visio but I'm hoping for more. Does anybody have any recommendations? CONCLUSION: @dlamblin had the most informative post, but the part I gained the most from was his/her (and others) mention of OmniGraffle, not Gliffy. I gave Gliffy a try, and it seemed neet for occational use, but since it's a Flash app (note: not AJAX as dlamblin mentioned) it's still a bit of a pain to use (no keyboard shortcuts for copy/paste was pretty much a deal breaker for me). I also tried SmartDraw, but it had 3-strikes-you're-out against it: The trial period was only 7 days long. It used some nonstandard (and visually jarring) GUI widget toolkit for its UI. At the very least it makes me suspicious (how do I know it will actually work & support the standard Windows features?) It crashed on me early into my trial. OmniGraffle looks like exactly what I want... except that it's Mac-only (so I couldn't give it a try). However, it got good reviews from my Mac-owning coworker, and I hope to try it on a friend's Mac soon. If it's good enough then I might spring for a new MacBook.

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