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Complex data types in WCF?

- by Hojou

I've run into a problem trying to return an object that holds a collection of childobjects that again can hold a collection of grandchild objects. I get an error, 'connection forcibly closed by host'. Is there any way to make this work? I currently have a structure resembling this: pseudo code: Person: IEnumerable<Order> Order: IEnumberable<OrderLine> All three objects have the DataContract attribute and all public properties i want exposed (including the IEnumerable's) have the DataMember attribute. I have multiple OperationContract's on my service and all the methods returning a single object OR an IEnumerable of an object works perfectly. It's only when i try to nest IEnumerable that it turns bad. Also in my client service reference i picked the generic list as my collection type. I just want to emphasize, only one of my operations/methods fail with this error - the rest of them work perfectly. EDIT (more detailed error description): [SocketException (0x2746): An existing connection was forcibly closed by the remote host] [IOException: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host.] [WebException: The underlying connection was closed: An unexpected error occurred on a receive.] [CommunicationException: An error occurred while receiving the HTTP response to http://myservice.mydomain.dk/MyService.svc. This could be due to the service endpoint binding not using the HTTP protocol. This could also be due to an HTTP request context being aborted by the server (possibly due to the service shutting down). See server logs for more details.] I tried looking for logs but i can't find any... also i'm using a WSHttpBinding and an http endpoint.

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Marshal.StringToCoTaskMemAnsi converting non-Latin characters when sending raw data to a printer

- by rem

For sending raw data to a thermal DATAMAX printer I'm using RawPrinterHelper class from this Microsoft KB article. When a string sent to printer contains only Latin characters, everything is OK. But non-Latin, in my case Russian characters in a string, are not printed correct. I think the problem is in using Marshal.StringToCoTaskMemAnsi method for converting the string: public static bool SendStringToPrinter(string szPrinterName, string szString) { IntPtr pBytes; Int32 dwCount; // How many characters are in the string? dwCount = szString.Length; // Assume that the printer is expecting ANSI text, and then convert // the string to ANSI text. pBytes = Marshal.StringToCoTaskMemAnsi(szString); // Send the converted ANSI string to the printer. SendBytesToPrinter(szPrinterName, pBytes, dwCount); Marshal.FreeCoTaskMem(pBytes); return true; } Just to note, Russian characters in the string are put in hex format, like "\x83", but nevertheless the method doesn't put this hex value in unmanaged memory as it is, but converts it, I think, according with ANSI code page to a character and then printer can not read it correctly. If I try to compose a file, using Hex editor and put correct hex values in place of non-Latin characters and then send the file to a printer using another method from the same class SendFileToPrinter, everything, including Russian characters is printed correctly. How in this case the problem with sending string, containing non-Latin characters, could be solved?

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How to fetch distinct values in Core Data?

- by Andy

So in looking through Core Data Snippets, I found the following code: ... [request setEntity:entity]; [request setResultType:NSDictionaryResultType]; [request setReturnsDistinctValues:YES]; [request setPropertiesToFetch:[NSArray arrayWithObject:@"<#Attribute name#>"]]; // Execute the fetch NSError *error; id requestedValue = nil; // WTF? This isn't defined or used anywhere NSArray *objects = [managedObjectContext executeFetchRequest:request error:&error]; if (objects == nil) { // handle the error } This is great and seems perfect for what I need...but how does one actually use it? I assume since it's returning dictionaries, I need a key to get at the values - but where's the key defined? Is that the "id requestedValue = nil" line? If so, how does "requestedValue" become the key? Xcode gives me a compiler warning about an unused variable at the "requestedValue" declaration. I feel like I'm missing something here. Thanks in advance for any assistance you can offer.

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Substitute values (for specific dates) from a second data frame to the first data frame

- by user1665355

I have two time series data frames: The first one: head(df1) : GMT MSCI ACWI DJGlbl Russell 1000 Russell Dev S&P GSCI Industrial S&P GSCI Precious 1999-03-01 -0.7000000 0.2000000 -0.1000000 -1.5000000 -1.0000000 -0.4000000 1999-03-02 -0.5035247 0.0998004 -0.7007007 -0.2030457 0.4040404 -0.3012048 1999-03-03 -0.2024291 0.2991027 0.0000000 -0.6103764 0.1006036 -0.1007049 1999-03-04 0.7099391 0.2982107 1.5120968 -0.1023541 0.5025126 0.4032258 1999-03-05 2.4169184 0.8919722 2.1847071 2.7663934 -1.2000000 0.0000000 1999-03-08 0.3933137 0.3929273 0.5830904 -0.0997009 -0.2024291 1.1044177 tail(df1) : GMT MSCI ACWI DJGlbl Russell 1000 Russell Dev S&P GSCI Industrial S&P GSCI Precious 2011-12-23 0.68241470 0.84790673 0.9441385 0.6116208 0.5822862 -0.2345300 2011-12-26 -0.05213764 0.00000000 0.0000000 0.0000000 0.0000000 0.0000000 2011-12-27 0.20865936 0.05254861 0.3117693 0.2431611 0.0000000 -0.7233273 2011-12-28 -0.62467465 -1.20798319 -1.1655012 -0.9702850 -2.0414381 -2.4043716 2011-12-29 0.52383447 0.47846890 0.8647799 0.5511329 -0.0933126 -1.2504666 2011-12-30 0.26055237 1.03174603 -0.4676539 1.2180268 1.9613948 1.7388017 The second one: head(df2) : GMT MSCI.ACWI DJGlbl Russell.1000 Russell.Dev S.P.GSCI.Industrial S.P.GSCI.Precious 1999-06-01 0.00000000 0.24438520 0.0000000 0 -0.88465521 0.008522842 1999-07-01 0.12630441 0.06755621 0.0000000 0 0.29394697 0.000000000 1999-08-02 0.07441812 0.18922829 0.0000000 0 0.02697299 -0.107155063 1999-09-01 -0.36952701 0.08684107 0.1117509 0 0.24520976 0.000000000 1999-10-01 0.00000000 0.00000000 0.0000000 0 0.00000000 1.941266205 1999-11-01 0.41879925 0.00000000 0.0000000 0 0.00000000 -0.197897901 tail(df2) : GMT MSCI.ACWI DJGlbl Russell.1000 Russell.Dev S.P.GSCI.Industrial S.P.GSCI.Precious 2011-07-01 0.00000000 0.0000000 0.0000000 0.0000000 0.00000000 -0.1141162 2011-08-01 0.00000000 0.0000000 0.0000000 0.0000000 0.02627347 0.0000000 2011-09-01 -0.02470873 0.2977585 -0.0911891 0.6367605 0.00000000 0.2830977 2011-10-03 0.42495188 0.0000000 0.4200743 -0.4420027 -0.41012646 0.0000000 2011-11-01 0.00000000 0.0000000 0.0000000 -0.6597739 0.00000000 0.0000000 2011-12-01 0.50273034 0.0000000 0.0000000 0.6476393 0.00000000 0.0000000 The first df cointains daily observations. The second df contains only the "first day of each month" forecasted values. I would like to substitute the values from the second df into the first one. In other words, the "first day of each month" values in the first df will be substituted for the "first day of each month" values from the second df. I tried to write an lapply loop that substitutes the values and was only trying to use match function. But I failed. I could not find the similar question at StackOverflow either... Greatful for any suggestions!

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What are the correct bindings for an NSComboBox for use with Core Data

- by theMikeSwan

Imagine if you will a Core Data app with two entities (Employee, and Department). Employees have a to-one relationship with department (department) and the inverse is a to-many relationship (employees). In the UI you can select individual Employee entities and edit the details in a detail area (there are of course other attributes and there is UI for adding and editing Department entities). When using a popup button the bindings are: content = PopUpArrayController.arrangedObjects content values = PopUpArrayController.arrangedObjects.name (name is an NSString) selected object = EmployeeArrayController.selection.department.name This allows for viewing of all departments in the popup menu, correct selection of the current Employee's department, and allows that department to be changed as expected. The goal is to change this for an NSComboBox so that the user can tab to the box and type the department name in without switching to the mouse. I have tried numerous different bindings to accomplish this. I even had it work for one run with these bindings: content = PopUpArrayController.arrangedObjects.name value = EmployeeArrayController.selection.department.name At least once this worked as expected (it even added a new department when the entered text did not match any existing department). Now however it will display the available Departments and auto complete but will not update the model with the correct value when the value is changed in the combo box. If the Department is set or changed with the popup the correct department is shown in the combo box. Does anyone know what I am missing? Thanks.

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LINQ Normalizing data

- by Brennan Mann

I am using an OMS that stores up to three line items per record in the database. Below is an example of an order containing five line items. Order Header Order Detail Prod 1 Prod 2 Prod 3 Order Detail Prod 4 Prod 5 One order header record and two detail records. My goal is have a one to one relation for details records(i.e., one detail record per line item). In the past, I used an UNION ALL SQL statement to extract the data. Is there a better approcach to this problem using LINQ? Below is my first attempt at using LINQ. Any feedback, suggestions or recommendations would greatly be appreciated. For what I have read, an UNION statement can tax the process? var orderdetail = (from o in context.ORDERSUBHEADs select new { edpNo = o.EDPNOS_001, price = o.EXTPRICES_001, qty = o.ITEMQTYS_001 } ).Union(from o in context.ORDERSUBHEADs select new { edpNo = o.EDPNOS_002, price = o.EXTPRICES_002, qty = o.ITEMQTYS_002 } ).Union(from o in context.ORDERSUBHEADs select new { edpNo = o.EDPNOS_003, price = o.EXTPRICES_003, qty = o.ITEMQTYS_003 });

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Core Data NSPredicate to filter results

- by Bryan

I have a NSManagedObject that contains a bID and a pID. Within the set of NSManagedObjects, I only want a subset returned and I'm struggling to find the correct NSPredicate or way to get what I need out of Core Data. Here's my full list: bid pid 41 0 42 41 43 0 44 0 47 41 48 0 49 0 50 43 There is a parent-child relationship above. Rules: If a record's PID = 0, it means that that record IS a parent record. If a record's PID != 0, then that record's PID refers to it's parent record's BID. Example: 1) BID = 41 is a parent record. Why? Because records BID=42 and record BID=47 have PID's of 41, meaning those are children of its PID record. 2) BID = 42 has a parent record with a BID = 41. 3) BID = 43 is a parent record. 4) BID = 44 is a parent record. 5) BID = 47 has a parent record with a BID = 41 because its PID = 41. See #1 above. 6) BID = 48 is a parent record. 7) BID = 49 is a parent record. 8) BID = 50 is a child record, and its parent record has a BID = 43. See the pattern? Now, basically from that, I want only the following rows fetched: bid pid 44 0 47 41 48 0 49 0 50 43 BID = 41, BID = 48, BID = 49 should all be returned because there are no records with a PID equal to their BID. BID = 47 should be returned because it is the most recent child of PID = 41. BID = 50 should be returned because it is the most recent child of PID = 43. Hope this helps explain it more.

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How should I go about implementing a points-to analysis in Maude?

- by reprogrammer

I'm going to implement a points-to analysis algorithm. I'd like to implement this analysis mainly based on the algorithm by Whaley and Lam. Whaley and Lam use a BDD based implementation of Datalog to represent and compute the points-to analysis relations. The following lists some of the relations that are used in a typical points-to analysis. Note that D(w, z) :- A(w, x),B(x, y), C(y, z) means D(w, z) is true if A(w, x), B(x, y), and C(y, z) are all true. BDD is the data structure used to represent these relations. Relations input vP0 (variable : V, heap : H) input store (base : V, field : F, source : V) input load (base : V, field : F, dest : V) input assign (dest : V, source : V) output vP (variable : V, heap : H) output hP (base : H, field : F, target : H) Rules vP(v, h) :- vP0(v, h) vP(v1, h) :- assign(v1, v2), vP(v2, h) hP(h1, f,h2) :- store(v1, f, v2), vP(v1, h1), vP(v2, h2) vP(v2, h2) :- load(v1, f, v2), vP(v1, h1), hP(h1, f, h2) I need to understand if Maude is a good environment for implementing points-to analysis. I noticed that Maude uses a BDD library called BuDDy. But, it looks like that Maude uses BDDs for a different purpose, i.e. unification. So, I thought I might be able to use Maude instead of a Datalog engine to compute the relations of my points-to analysis. I assume Maude propagates independent information concurrently. And this concurrency could potentially make my points-to analysis faster than sequential processing of rules. But, I don't know the best way to represent my relations in Maude. Should I implement BDD in Maude myself, or Maude's internal unification based on BDD has the same effect?

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haskell: a data structure for storing ascending integers with a very fast lookup

- by valya

Hello! (This question is related to my previous question, or rather to my answer to it.) I want to store all qubes of natural numbers in a structure and look up specific integers to see if they are perfect cubes. For example, cubes = map (\x -> x*x*x) [1..] is_cube n = n == (head $ dropWhile (<n) cubes) It is much faster than calculating the cube root, but It has complexity of O(n^(1/3)) (am I right?). I think, using a more complex data structure would be better. For example, in C I could store a length of an already generated array (not list - for faster indexing) and do a binary search. It would be O(log n) with lower ?oefficient than in another answer to that question. The problem is, I can't express it in Haskell (and I don't think I should). Or I can use a hash function (like mod). But I think it would be much more memory consuming to have several lists (or a list of lists), and it won't lower the complexity of lookup (still O(n^(1/3))), only a coefficient. I thought about a kind of a tree, but without any clever ideas (sadly I've never studied CS). I think, the fact that all integers are ascending will make my tree ill-balanced for lookups. And I'm pretty sure this fact about ascending integers can be a great advantage for lookups, but I don't know how to use it properly (see my first solution which I can't express in Haskell).

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Core data relationship memory leak

- by cfihelp

I have a strange (to me) memory leak when accessing an entity in a relationship. Series and Tiles have an inverse relationship to each other. // set up the fetch request NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"Series" inManagedObjectContext:managedObjectContext]; [fetchRequest setEntity:entity]; // grab all of the series in the core data store NSError *error = nil; availableSeries = [[NSArray alloc] initWithArray:[managedObjectContext executeFetchRequest:fetchRequest error:&error]]; [fetchRequest release]; // grab one of the series Series *currentSeries = [availableSeries objectAtIndex:1]; // load all of the tiles attached to the series through the relationship NSArray *myTiles = [currentSeries.tile allObjects]; // 16 byte leak here! Instruments reports back that the final line has a 16 byte leak cause by NSPlaceHolderString. Stack trace: 2 UIKit UIApplicationMain 3 UIKit -[UIApplication _run] 4 CoreFoundation CFRunLoopRunInMode 5 CoreFoundation CFRunLoopRunSpecific 6 GraphicsServices PurpleEventCallback 7 UIKit _UIApplicationHandleEvent 8 UIKit -[UIApplication sendEvent:] 9 UIKit -[UIApplication handleEvent:withNewEvent:] 10 UIKit -[UIApplication _runWithURL:sourceBundleID:] 11 UIKit -[UIApplication _performInitializationWithURL:sourceBundleID:] 12 Memory -[AppDelegate_Phone application:didFinishLaunchingWithOptions:] /Users/cfish/svnrepo/Memory/src/Memory/iPhone/AppDelegate_Phone.m:49 13 UIKit -[UIViewController view] 14 Memory -[HomeScreenController_Phone viewDidLoad] /Users/cfish/svnrepo/Memory/src/Memory/iPhone/HomeScreenController_Phone.m:58 15 CoreData -[_NSFaultingMutableSet allObjects] 16 CoreData -[_NSFaultingMutableSet willRead] 17 CoreData -[NSFaultHandler retainedFulfillAggregateFaultForObject:andRelationship:withContext:] 18 CoreData -[NSSQLCore retainedRelationshipDataWithSourceID:forRelationship:withContext:] 19 CoreData -[NSSQLCore newFetchedPKsForSourceID:andRelationship:] 20 CoreData -[NSSQLCore rawSQLTextForToManyFaultStatement:stripBindVariables:swapEKPK:] 21 Foundation +[NSString stringWithFormat:] 22 Foundation -[NSPlaceholderString initWithFormat:locale:arguments:] 23 CoreFoundation _CFStringCreateWithFormatAndArgumentsAux 24 CoreFoundation _CFStringAppendFormatAndArgumentsAux 25 Foundation _NSDescriptionWithLocaleFunc 26 CoreFoundation -[NSObject respondsToSelector:] 27 libobjc.A.dylib class_respondsToSelector 28 libobjc.A.dylib lookUpMethod 29 libobjc.A.dylib _cache_addForwardEntry 30 libobjc.A.dylib _malloc_internal I think I'm missing something obvious but I can't quite figure out what. Thanks for your help! Update: I've copied the offending chunk of code to the first part of applicationDidFinishLaunching and it still leaks. Could there be something wrong with my model?

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Backwards compatibility when using Core Data

- by Alex

Could anybody shed some light as to why is my app crashing with the following error on iPhone OS 2.2.1 dyld: Symbol not found: _OBJC_CLASS_$_NSPredicate Referenced from: /var/mobile/Applications/456F243F-468A-4969-9BB7-A4DF993AE89C/AppName.app/AppName Expected in: /System/Library/Frameworks/Foundation.framework/Foundation I have weak linked CoreData.framework, and have the Base SDK set to 3.0 and Deployment Target set to SDK 2.2 The app already uses other 3.0 features when available and I did not have any problems with those. But apparently the backward-compatibility methods used for other features do not work with Core Data. The app crashes before app delegate's applicationDidFinishLaunching gets called. Here's the debugger log: [Session started at 2010-05-25 20:17:03 -0400.] GNU gdb 6.3.50-20050815 (Apple version gdb-1119) (Thu May 14 05:35:37 UTC 2009) Copyright 2004 Free Software Foundation, Inc. GDB is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Type "show copying" to see the conditions. There is absolutely no warranty for GDB. Type "show warranty" for details. This GDB was configured as "--host=i386-apple-darwin --target=arm-apple-darwin".tty /dev/ttys001 Loading program into debugger… sharedlibrary apply-load-rules all warning: Unable to read symbols from "MessageUI" (not yet mapped into memory). warning: Unable to read symbols from "CoreData" (not yet mapped into memory). Program loaded. target remote-mobile /tmp/.XcodeGDBRemote-12038-42 Switching to remote-macosx protocol mem 0x1000 0x3fffffff cache mem 0x40000000 0xffffffff none mem 0x00000000 0x0fff none run Running… [Switching to thread 10755] [Switching to thread 10755] Re-enabling shared library breakpoint 1 Re-enabling shared library breakpoint 2 Re-enabling shared library breakpoint 3 Re-enabling shared library breakpoint 4 Re-enabling shared library breakpoint 5 (gdb) continue warning: Unable to read symbols for ""/Users/alex/iPhone Projects/AppName/build/Debug-iphoneos"/AppName.app/AppName" (file not found). dyld: Symbol not found: _OBJC_CLASS_$_NSPredicate Referenced from: /var/mobile/Applications/456F243F-468A-4969-9BB7-A4DF993AE89C/AppName.app/AppName Expected in: /System/Library/Frameworks/Foundation.framework/Foundation (gdb)

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Data Binding to an object in C#

- by Allen

Objective-c/cocoa offers a form of binding where a control's properties (ie text in a textbox) can be bound to the property of an object. I am trying to duplicate this functionality in C# w/ .Net 3.5. I have created the following very simple class in the file MyClass.cs: class MyClass { private string myName; public string MyName { get { return myName; } set { myName = value; } } public MyClass() { myName = "Allen"; } } I also created a simple form with 1 textbox and 1 button. I init'd one instance of Myclass inside the form code and built the project. Using the DataSource Wizard in Vs2008, i selected to create a data source based on object, and selected the MyClass assembly. This created a datasource entity. I changed the databinding of the textbox to this datasource; however, the expected result (that the textbox's contents would be "allen") was not achieved. Further, putting text into the textbox is not updating the name property of the object. I know i'm missing something fundamental here. At some point i should have to tie my instance of the MyClass class that i initialized inside the form code to the textbox, but that hasn't occurred. Everything i've looked at online seems to gloss over using DataBinding with an object (or i'm missing the mark entirely), so any help is great appreciated. ----Edit--- Utilizing what i learned by the answers, i looked at the code generated by Visual Studio, it had the following: this.myClassBindingSource.DataSource = typeof(BindingTest.MyClass); if i comment that out and substitute : this.myClassBindingSource.DataSource = new MyClass(); i get the expected behavior. Why is the default code generated by VS like it is? Assuming this is more correct than the method that works, how should i modify my code to work within the bounds of what VS generated?

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Where to put data management rules for complex data validation in ASP.NET MVC?

- by TheRHCP

Hello, I am currently working on an ASP.NET MVC2 project. This is the first time I am working on a real MVC web application. The ASP.NET MVC website really helped me to get started really fast, but I still have some obscure knowledge concerning datamodel validation. My problem is that I do not really know where to manage my filled datamodel when it comes to complex validation rules. For example, validating a string field with a Regex is quite easy and I know that I just have to decorate my field with a specific attribute, so data management rules are implemented in the model. But if I have multiple fields that I need to validate which each other, for example multiple datetime that need to be correctly set following a specific time rule, where do I need to validate them? I know that I could create my own validation attributes, but sometimes validation ask a specific validation path which is to complex to be validated using attributes. This first question also leads me to a related question which is, is it right to validate a model in the controller? Because for the moment that is the only way I found for complex validation. But I find this a bit dirty and I feel it does not really fit a the controller role and much harder to test (multiple code path). Thanks.

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VB.NET handling data between different forms

- by niuchu

Hi, I'm writing a simple application - address book. User enters new addresses and they are added as an entry to a list visible on the main form (frmStart). I use one form to add and edit (AddContForm). Add button on the frmStart works fine, however I experience some problems with the edit button as when I press it and enter new data they are added as new entry however the previous entry is still there. Logic is handled by Contact.vb class. Please let me know how to fix this problem. Here is the code: Contact.vb Public Class Contact Public Contact As String Public Title As String Public Fname As String Public Surname As String Public Address As String Private myCont As String Public Property Cont() Get Return myCont End Get Set(ByVal value) myCont = Value End Set End Property Public Overrides Function ToString() As String Return Me.Cont End Function Public Sub Display() Dim C As New Contact C.Cont = frmAddCont.txtTitle.Text C.Fname = frmAddCont.txtFName.Text C.Surname = frmAddCont.txtSName.Text C.Address = frmAddCont.txtAddress.Text frmStart.lstContact.Items.Add(C) End Sub End Class Here is frmStart.vb Public Class frmStart Public Button As String Private Sub btnAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAdd.Click Button = "" Button = "Add" frmAddCont.ShowDialog() End Sub Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDel.Click Button = "" Button = "Del" Dim DelCont As Contact DelCont = Me.lstContact.SelectedItem() lstContact.Items.Remove(DelCont) End Sub Private Sub lstContact_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles lstContact.SelectedIndexChanged End Sub Private Sub btnEdit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnEdit.Click Button = "" Button = "Edit" Dim C As Contact If lstContact.SelectedItem IsNot Nothing Then C = DirectCast(lstContact.SelectedItem, Contact) frmAddCont.ShowDialog() End If End Sub End Class Here is AddContFrm.vb Public Class frmAddCont Public Class ControlObject Dim Title As String Dim FName As String Dim SName As String Dim Address As String Dim TelephoneNumber As Integer Dim emailAddress As String Dim Website As String Dim Photograph As String End Class Private Sub btnConfirmAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnConfirmAdd.Click Dim B As String B = frmStart.Button Dim C As New Contact C.Display() Me.Hide() If B = "Edit" Then C = DirectCast(frmStart.lstContact.SelectedItem, Contact) frmStart.lstContact.SelectedItems.Remove(C) End If End Sub Private Sub frmAddCont_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load End Sub End Class

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how to continuously send data without blocking?

- by Donal Rafferty

I am trying to send rtp audio data from my Android application. I currently can send 1 RTP packet with the code below and I also have another class that extends Thread that listens to and receives RTP packets. My question is how do I continuously send my updated buffer through the packet payload without blocking the receiving thread? public void run() { isRecording = true; android.os.Process.setThreadPriority (android.os.Process.THREAD_PRIORITY_URGENT_AUDIO); int buffersize = AudioRecord.getMinBufferSize(8000, AudioFormat.CHANNEL_CONFIGURATION_MONO, AudioFormat.ENCODING_PCM_16BIT); Log.d("BUFFERSIZE","Buffer size = " + buffersize); arec = new AudioRecord(MediaRecorder.AudioSource.MIC, 8000, AudioFormat.CHANNEL_CONFIGURATION_MONO, AudioFormat.ENCODING_PCM_16BIT, buffersize); short[] readBuffer = new short[80]; byte[] buffer = new byte[160]; arec.startRecording(); while(arec.getRecordingState() == AudioRecord.RECORDSTATE_RECORDING){ int frames = arec.read(readBuffer, 0, 80); @SuppressWarnings("unused") int lenghtInBytes = codec.encode(readBuffer, 0, buffer, frames); RtpPacket rtpPacket = new RtpPacket(); rtpPacket.setV(2); rtpPacket.setX(0); rtpPacket.setM(0); rtpPacket.setPT(0); rtpPacket.setSSRC(123342345); rtpPacket.setPayload(buffer, 160); try { rtpSession2.sendRtpPacket(rtpPacket); } catch (UnknownHostException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (RtpException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } So when I send on one device and receive on another I get decent audio, but when I send and receive on both I get broken sound like its taking turns to send and receive audio. I have a feeling it could be to do with the while loop? it could be looping around in there and not letting anything else run?

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Core data setReturnsDistinctResult not working

- by Moze

So i'm building a small application, it uses core data database of ~25mb size with 4 entities. It's for bus timetables. In one table named "Stop" there are have ~1300 entries of bus stops with atributes "name", "id", "longitude", "latitude" and couple relationships. Now there are many stops with same name but different coordinates and id. Search is implemented using NSPredicate. So I want to show all distinct stop names in table view, i'm using setReturnsDistinctResults with NSDictionaryResultType and setPropertiesToFetch. But setReturnsDistinctResult is not working and I'm still getting all entries. Heres code: - (NSFetchRequest *)fetchRequest { if (fetchRequest == nil) { fetchRequest = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"Stop" inManagedObjectContext:managedObjectContext]; [fetchRequest setEntity:entity]; NSArray *sortDescriptors = [NSArray arrayWithObject:[[[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES] autorelease]]; [fetchRequest setSortDescriptors:sortDescriptors]; [fetchRequest setResultType:NSDictionaryResultType]; [fetchRequest setPropertiesToFetch:[NSArray arrayWithObject:[[entity propertiesByName] objectForKey:@"name"]]]; [fetchRequest setReturnsDistinctResults:YES]; DebugLog(@"fetchRequest initialized"); } return fetchRequest; } ///////////////////// - (NSFetchedResultsController *)fetchedResultsController { if (self.predicateString != nil) { self.predicate = [NSPredicate predicateWithFormat:@"name CONTAINS[cd] %@", self.predicateString]; [self.fetchRequest setPredicate:predicate]; } else { self.predicate = nil; [self.fetchRequest setPredicate:predicate]; } fetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:self.fetchRequest managedObjectContext:managedObjectContext sectionNameKeyPath:sectionNameKeyPath cacheName:nil]; return fetchedResultsController; } ////////////// - (UITableViewCell *)tableView:(UITableView *)table cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"Cell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease]; } cell.textLabel.text = [[fetchedResultsController objectAtIndexPath:indexPath] valueForKey:@"name"]; return cell; }

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Core Data Inferred Migration – Automatic "lightweight" vs Manual

- by ohhorob

I've updated the model of an existing iPhone app in some simple ways (remove attribute, add attribute, remove index), and can use automatic lightweight migration to migrate the persistent store. Due to the typical size of the data set, the processing time is not insignificant, and warrants feedback for the user. NSMigrationManager provides a simple but useful migrationProgress value that sends KVO notifications as the migration is performed. That forms the basis of providing feedback, however attempting to use an inferred model ([NSMappingModel inferredMappingModelForSourceModel:destinationModel:error:]) results in drastically different timing for the exact same dataset. Profile results on and original iPhone (2G) Automatic inferred lightweight migration PROFILE: CacheManager -migrateStore PROFILE: 0.6130 (+0.6130) models loaded PROFILE: 1.1759 (+0.5629) delegate -CacheManagerWillMigrate: PROFILE: 1.2516 (+0.0757) persistent store coordinator loaded PROFILE: 5.1436 (+3.8920) automatic lightweight migration completed PROFILE: 5.5435 (+0.3999) delegate -CacheManagerDidFinishMigration:withError: Manual inferred migration PROFILE: CacheManager -migrateStore PROFILE: 0.6660 (+0.6660) models loaded PROFILE: 1.1471 (+0.4811) inferred mapping model generated PROFILE: 1.4046 (+0.2574) delegate -CacheManagerWillMigrate: PROFILE: 1.5058 (+0.1013) persistent store coordinator loaded PROFILE: 22.6952 (+21.1894) manual migration completed PROFILE: 23.1478 (+0.4525) delegate -CacheManagerDidFinishMigration:withError: So, with an inferred model, the manual migration takes over 5 times longer than automatic! It's a big inconsistency, and the lightweight option that NSPersistentStoreCoordinator -addPersistentStoreWithType:configuration:URL:options:error: provides absolutely no indication of progress while processing. Can anybody provide a supported way to get the migrationProgress values during automatic migration, OR a way to configure an inferred mapping model to be as fast during manual processing as automatic?

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Core Data @sum aggregate

- by nasim

I am getting an exception when I try to get @sum on a column in iPhone Core-Data application. My two models are following - Task model: @interface Task : NSManagedObject { } @property (nonatomic, retain) NSString * taskName; @property (nonatomic, retain) NSSet* completion; @end @interface Task (CoreDataGeneratedAccessors) - (void)addCompletionObject:(NSManagedObject *)value; - (void)removeCompletionObject:(NSManagedObject *)value; - (void)addCompletion:(NSSet *)value; - (void)removeCompletion:(NSSet *)value; @end Completion model: @interface Completion : NSManagedObject { } @property (nonatomic, retain) NSNumber * percentage; @property (nonatomic, retain) NSDate * time; @property (nonatomic, retain) Task * task; @end And here is the fetch: NSFetchRequest *request = [[NSFetchRequest alloc] init]; request.entity = [NSEntityDescription entityForName:@"Task" inManagedObjectContext:context]; NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"taskName" ascending:YES]; request.sortDescriptors = [NSArray arrayWithObject:sortDescriptor]; NSError *error; NSArray *results = [context executeFetchRequest:request error:&error]; NSArray *parents = [results valueForKeyPath:@"taskName"]; NSArray *children = [results valueForKeyPath:@"[email protected]"]; NSLog(@"%@ %@", parents, children); [request release]; [sortDescriptor release]; The exception is thrown at the fourth line from bottom. The thrown exception is: *** -[NSCFSet decimalValue]: unrecognized selector sent to instance 0x3b25a30 *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[NSCFSet decimalValue]: unrecognized selector sent to instance 0x3b25a30' I would very much appreciate any kind of help. Thanks.

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Windows Phone app: Binding data in a UserControl which is contained in a ListBox

- by Alexandros Dafkos

I have an "AddressListBox" ListBox that contains "AddressDetails" UserControl items, as shown in the .xaml file extract below. The Addresses collection is defined as ObservableCollection< Address Addresses and Street, Number, PostCode, City are properties of the Address class. The binding fails, when I use the "{Binding property}" syntax shown below. The binding succeeds, when I use the "dummy" strings in the commented-out code. I have also tried "{Binding Path=property}" syntax without success. Can you suggest what syntax I should use for binding the data in the user controls? <ListBox x:Name="AddressListBox" DataContext="{StaticResource dataSettings}" ItemsSource="{Binding Path=Addresses, Mode=TwoWay}"> <ListBox.ItemTemplate> <DataTemplate>  <usercontrols:AddressDetails AddressRoad="{Binding Street}" AddressNumber="{Binding Number}" AddressPostCode="{Binding PostCode}" AddressCity="{Binding City}"> </usercontrols:AddressDetails> </DataTemplate> </ListBox.ItemTemplate> </ListBox>

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NSUndoManager, Core Data and selective undo/redo

- by Combat

I'm working on a core data application that has a rather large hierarchy of managed objects similar to a tree. When a base object is created, it creates a few child objects which in turn create their own child objects and so on. Each of these child objects may gather information using NSURLConnections. Now, I'd like to support undo/redo with the undoManager in the managedObjectContext. The problem is, if a user creates a base object, then tries to undo that action, the base object is not removed. Instead, one or more of the child objects may be removed. Obviously this type of action is unpredictable and unwanted. So I tried disabling undo registration by default. I did this by calling disableUndoRegistration: before anything is modified in the managedObjectContext. Then, enabling undo registration before base operations such as creating a base object the again re-disabling registrations afterwords. Now when i try to undo, I get this error: undo: NSUndoManager 0x1026428b0 is in invalid state, undo was called with too many nested undo groups Thoughts?

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What is SSIS order of data transformation component method calls

- by Ron Ruble

I am working on a custom data transformation component. I'm using NUnit and NMock2 to test as I code. Testing and getting the custom UI and other features right is a huge pain, in part because I can't find any documentation about the order in which SSIS invokes methods on the component at design time as well as runtime. I can correct the issues readily enough, but it's tedious and time consuming to unregister the old version, register the new version, fire up the test ssis package, try to display the UI, get an obscure error message, backtrace it, modify the component and continue. One of the big issues involves the UI component needing access to the componentmetadata and buffermanager properties of the component at design time, and what I need to provide for to support properties that won't be initialized until after the user enters them in the UI. I can work through it; but if someone knows of some docs or tips that would speed me up, I'd greatly appreciate it. The samples I've found havn't been much use; they seem to be directed to showing off cool stuff (Twitter, weather.com) rather than actual work. Thanks in advance.

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Core Data - 'calculated' attributes

- by nephilim

I have two entities: A and B A has two properties from and to, both pointing to the B entity. B as a fetched property to A with predicate from == $FETCH_SOURCE or to = $FETCH_SOURCE -- (from) -> A -- (to) -> B <- (As) -- In my application I select a certain B instance, and then show all of its A instances. Now, in my table the columns are bound to an array controller containing the selected A instances. I want to 'merge' the from and to columns. I already know one of the columns will be equal to the selected B instance, so now I'm only interested in the second value. The options I see: create a custom class for the B entity and create a method that returns either value. It should somehow be able to retrieve which B instance is currently selected. create a custom DataSource. Most columns are still using bindings, so then we'd have to access the NSArrayController's array so we're sure we have the right object. create a custom DataSource, remove the NSArrayController and do all the Core Data stuff ourselves. Is there any 'right' way to solve this?

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getting data from tableviewcell to 2nd view

- by chubsta

I am very new to this and am trying to learn by creating a few little apps for myself. I have a navigation-based app where the user taps the row to select a film title - i then want the second view to show details of the film. Thanks to a very helpful person here i am getting the results of the row pressed as 'rowTitle' as follows : (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { NSString *key = [keys objectAtIndex:indexPath.section]; NSArray *nameSection = [names objectForKey:key]; NSString *rowTitle = [nameSection objectAtIndex:indexPath.row]; NSLog(@"rowTitle = %@", rowTitle); [tableView deselectRowAtIndexPath:indexPath animated:YES]; I am, however, struggling to make the data at 'rowTitle' available to the 2nd view - basically, if i can get the info - for example rowTitle is "aliens2" - i want to be able to add a new extension to the end of the string returned by 'rowTitle' in order to point to an image (if that makes sense) in the second view... something like tempImageName=[** this is where the info from rowTitle needs to be i suppose**]; tempImageType=@".png"; finalImageName=[tempImageName stringByAppendingString:tempImageType]; does this make sense to anyone (apologies if it doesnt - i know what i want but how to explain it is a little more awkward!) Thanks again for any help anyone can give (and any help as to formatting these questions would be useful too obviously!!)!

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Core Data: Overkill for simple, static UITableView-based iPhone App?

- by David Foster

Hello! I have a rather simple iPhone app consisting of numerous views containing a single, grouped table view. These views are held together in navigation controllers which are grouped in a tab bar. Simple stuff. My table views do little more than list text (like "Dog", "Cat" and "Weasel") and this data is being served from a collection of plists. It's perhaps worth mentioning too that these tables are 'static' in the sense that their data is pre-determined and will only ever be amended—and if so, very rarely indeed—by the developer (in this case, moi). This rudimentary approach has reached its limits though, and I think I'm going to need something a bit more relational. I have worked a tad with Core Data in the past, but only with apps whose data is determined by user input. I have four closely related questions: Is Core Data overkill for an app consisting mainly of a selection of simple table views? Do you recommend using Core Data to manage data which is predetermine and extremely unlikely to ever change? Can one lock Core Data down so that its data can't change, thereby relinquishing my responsibility as the developer to handle the editing and saving of the managed object context? How do I go about giving Core Data my predetermined data, and in a format I know that it can work with? Thanks a bunch guys.

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Core Data: Deleting causes 'NSObjectInaccessibleException' from NSOperation with a reference to a deleted object

- by Bryan Irace

My application has NSOperation subclasses that fetch and operate on managed objects. My application also periodically purges rows from the database, which can result in the following race condition: An background operation fetches a bunch of objects (from a thread-specific context). It will iterate over these objects and do something with their properties. A bunch of rows are deleted in the main managed object context. The background operation accesses a property on an object that was deleted from the main context. This results in an 'NSObjectInaccessibleException', reason: 'CoreData could not fulfill a fault' Ideally, the objects that are fetched by the NSOperation can be operated on even if one is deleted in the main context. The best way I can think to achieve this is either to: Call [request setReturnsObjectsAsFaults:NO] to ensure that Core Data won't try to fulfill a fault for an object that no longer exists in the main context. The problem here is I may need to access the object's relationships, which (to my understanding) will still be faulted. Iterate through the managed objects up front and copy the properties I will need into separate non-managed objects. The problem here is that (I think) I will need to synchronize/lock this part, in case an object is deleted in the main context before I can finish copying. Am I missing something obvious? It doesn't seem like what I'm trying to accomplish is too out of the ordinary. Thanks for your help.

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