Search Results

Search found 27144 results on 1086 pages for 'tail call optimization'.

Page 424/1086 | < Previous Page | 420 421 422 423 424 425 426 427 428 429 430 431  | Next Page >

  • How can I use io.StringIO() with the csv module?

    - by Tim Pietzcker
    I tried to backport a Python 3 program to 2.7, and I'm stuck with a strange problem: >>> import io >>> import csv >>> output = io.StringIO() >>> output.write("Hello!") # Fail: io.StringIO expects Unicode Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: unicode argument expected, got 'str' >>> output.write(u"Hello!") # This works as expected. 6L >>> writer = csv.writer(output) # Now let's try this with the csv module: >>> csvdata = [u"Hello", u"Goodbye"] # Look ma, all Unicode! (?) >>> writer.writerow(csvdata) # Sadly, no. Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: unicode argument expected, got 'str' According to the docs, io.StringIO() returns an in-memory stream for Unicode text. It works correctly when I try and feed it a Unicode string manually. Why does it fail in conjunction with the csv module, even if all the strings being written are Unicode strings? Where does the str come from that causes the Exception? (I do know that I can use StringIO.StringIO() instead, but I'm wondering what's wrong with io.StringIO() in this scenario)

    Read the article

  • Maximize/Minimize is causing Close Button to be re-enabled after disabling it -- Why?

    - by Brainsick
    I have used P/Invoke to call GetSystemMenu and EnableMenuItem (win32api) to disable the close functionality. However, after minimizing or maximizing my Windows Forms application the button is re-enabled. Obviously minimizing or maximizing is causing the behavior, but how? I'm not sure where to look to prevent this behavior. Should I be preventing the maximize and minimize behavior or is there something particularly wrong with the way in which I P/Invoked the calls? Once the application (main form) has loaded, I call the static method from a button click. class PInvoke { // P/Invoke signatures [DllImport("user32.dll")] static extern IntPtr GetSystemMenu(IntPtr hWnd, bool bRevert); [DllImport("user32.dll")] static extern bool EnableMenuItem(IntPtr hMenu, uint uIDEnableItem, uint uEnable); // SysCommand (WM_SYSCOMMAND) constant internal const UInt32 SC_CLOSE = 0xF060; // Constants used with Add/Check/EnableMenuItem internal const UInt32 MF_BYCOMMAND = 0x00000000; internal const UInt32 MF_ENABLED = 0x00000000; internal const UInt32 MF_GRAYED = 0x00000001; internal const UInt32 MF_DISABLED = 0x00000002; /// <summary> /// Sets the state of the Close (X) button and the System Menu close functionality. /// </summary> /// <param name="window">Window or Form</param> /// <param name="bEnabled">Enabled state</param> public static void EnableCloseButton(IWin32Window window, bool bEnabled) { IntPtr hSystemMenu = GetSystemMenu(window.Handle, false); EnableMenuItem(hSystemMenu, SC_CLOSE, MF_BYCOMMAND | (bEnabled ? MF_ENABLED : MF_GRAYED)); } }

    Read the article

  • How do I automatically update hundreds of images in an HTML page using jquery?

    - by Chris
    I have an HTML page where I want to refresh a lot of images every 30 seconds after the HTML page has been downloaded. I understand how to do this with Jquery and a single image, but I want to use about 200 custom urls to determine the current image to display for over 200 images. I need to find an efficient way to have jquery call the custom url associated with each image to download the url for the needed image as it changes, and then update the image in the page when it changes. Current hyperlink example to demonstrate the custom urls. <A href="/urlThatReturnsCurrentImageURL/1234/4567">link to url for image</A> Each custom url will return an image tag like this (or any other text that makes this simpler for jquery) <img src="/static/someImage.jpg"> What is the simplest way to have jquery call the custom url for each image to download the image url, image html, or some other text that jquery can use to download the right image every 30 seconds? Please keep in mind that I will have about 200 of these on a page.

    Read the article

  • .NET remoting: System references wrong .NET dll, but how to cure ?

    - by Quandary
    Question: I defined an interface like below. The problem now is, that when I add the dll (API.dll) as reference in an asp.net project, it references a wrong API.dll, though I referenced the correct dll. In turn, it doesn't find GetLDAPlookup, but there is another method that is not in defined here, but in an older version of API.dll... I rebuilt the dll I referenced, so it is definitely the latest version that I added as reference. Do I have to add another GUID, or something ? Imports System.Runtime.InteropServices Namespace RemoteObject ''' <summary> ''' Defines server interface which will be deployed on every client ''' </summary> ''' <GuidAttribute("921DE547-32FA-40BB-961A-EA390B7AE27D")> _ Public Interface IServerMethods ''' <summary> ''' Function to call the server from the client ''' </summary> ''' <param name="strMessage">Some text</param> ''' Sub ServerPrint(ByVal strMessage As String) ''' <summary> ''' Function to call the server from the client ''' </summary> ''' <param name="strMessage">Some text</param> ''' <returns>Some interesting text</returns> ''' Function GetLDAPlookup(ByVal strMessage As String) As System.Data.DataSet End Interface End Namespace

    Read the article

  • Response Redirect - Open Link in New Window

    - by bacis09
    First, I've taken the time to review this question which seems to be the most similar, however, the solution that seems to have been selected will not work in my scenario.Not to mention I worry about some of the comments claiming it to be brittle or an inadequate solution. http://stackoverflow.com/questions/104601/asp-net-response-redirect-to-new-window -We have an XML document which basically contains all of the information for a Side menu. -We have numerous URLS which are stored in a constants class. -One of the elements in a string of XML (well call it label) is used to determine if the menu item is created as a LinkButton or a Label. -Links use a custom user control that is used standard for all links across the application (why suggestion on similar thread doesn't work - I don't want all links to open in a new window - just one) -One of the elements in a string of XML (well call it function) is used in a Switch statement to generate our links using Response Redirect. It may look something like this. switch (function) { case goto 1: string url; if (user_group == 1) { url = Constants.CONSTANT1 } else { url = Constants.CONSTANT2 } Response.Redirect(url) case goto 2: ...... default: ...... break; } Given this scenario, I'm trying to find the best way to quickly open a New Window, when a specific case in this switch statement is met. Can it be done with Response Redirect (this seems to be arguable - people say no it can't, yet other people say they have made it work)? If not, what alternative can work here?

    Read the article

  • How to debug python del self.callbacks[s][cid] keyError when the error message does not indicate where in my code the error is

    - by lkloh
    In a python program I am writing, I get an error saying Traceback (most recent call last): File "/Applications/Canopy.app/appdata/canopy-1.4.0.1938.macosx- x86_64/Canopy.app/Contents/lib/python2.7/lib-tk/Tkinter.py", line 1470, in __call__ return self.func(*args) File "/Users/lkloh/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/matplotlib/backends/backend_tkagg.py", line 413, in button_release_event FigureCanvasBase.button_release_event(self, x, y, num, guiEvent=event) File "/Users/lkloh/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/matplotlib/backend_bases.py", line 1808, in button_release_event self.callbacks.process(s, event) File "/Users/lkloh/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/matplotlib/cbook.py", line 525, in process del self.callbacks[s][cid] KeyError: 103 Do you have any idea how I can debug this/ what could be wrong? The error message does not point to anywhere in code I have personally written. I get the error message only after I close my GUI window, but I want to fix it even though it does not break the functionality of my code. The error is part of a very big program I am writing, so I cannot post all my code, but below is code I think is relevant: def save(self, event): self.getSaveAxes() self.save_connect() def getSaveAxes(self): saveFigure = figure(figsize=(8,1)) saveFigure.clf() # size of save buttons rect_saveHeaders = [0.04,0.2,0.2,0.6] rect_saveHeadersFilterParams = [0.28,0.2,0.2,0.6] rect_saveHeadersOverride = [0.52,0.2,0.2,0.6] rect_saveQuit = [0.76,0.2,0.2,0.6] #initalize axes saveAxs = {} saveAxs['saveHeaders'] = saveFigure.add_axes(rect_saveHeaders) saveAxs['saveHeadersFilterParams'] = saveFigure.add_axes(rect_saveHeadersFilterParams) saveAxs['saveHeadersOverride'] = saveFigure.add_axes(rect_saveHeadersOverride) saveAxs['saveQuit'] = saveFigure.add_axes(rect_saveQuit) self.saveAxs = saveAxs self.save_connect() self.saveFigure = saveFigure show() def save_connect(self): #set buttons self.bn_saveHeaders = Button(self.saveAxs['saveHeaders'], 'Save\nHeaders\nOnly') self.bn_saveHeadersFilterParams = Button(self.saveAxs['saveHeadersFilterParams'], 'Save Headers &\n Filter Parameters') self.bn_saveHeadersOverride = Button(self.saveAxs['saveHeadersOverride'], 'Save Headers &\nOverride Data') self.bn_saveQuit = Button(self.saveAxs['saveQuit'], 'Quit') #connect buttons to functions they trigger self.cid_saveHeaders = self.bn_saveHeaders.on_clicked(self.save_headers) self.cid_savedHeadersFilterParams = self.bn_saveHeadersFilterParams.on_clicked(self.save_headers_filterParams) self.cid_saveHeadersOverride = self.bn_saveHeadersOverride.on_clicked(self.save_headers_override) self.cid_saveQuit = self.bn_saveQuit.on_clicked(self.save_quit) def save_quit(self, event): self.save_disconnect() close()

    Read the article

  • I just wanted to DES 4096 bytes of data with a 128 bits key...

    - by badp
    ...and what the nice folks at OpenSSL gratiously provide me with is this. :) Now, since you shouldn't be guessing when using cryptography, I come here for confirmation: what is the function call I want to use? What I understood A 128 bits key is 16 byte large, so I'll need double DES (2 × 8 byte). This leaves me with only a few function calls: void DES_ede2_cfb64_encrypt(const unsigned char *in, unsigned char *out, long length, DES_key_schedule *ks1, DES_key_schedule *ks2, DES_cblock *ivec, int *num, int enc); void DES_ede2_cbc_encrypt(const unsigned char *input, unsigned char *output, long length, DES_key_schedule *ks1, DES_key_schedule *ks2, DES_cblock *ivec, int enc); void DES_ede2_cfb64_encrypt(const unsigned char *in, unsigned char *out, long length, DES_key_schedule *ks1, DES_key_schedule *ks2, DES_cblock *ivec, int *num, int enc); void DES_ede2_ofb64_encrypt(const unsigned char *in, unsigned char *out, long length, DES_key_schedule *ks1, DES_key_schedule *ks2, DES_cblock *ivec, int *num); In this case, I guess the function I want to call DES_ede2_cfb64_encrypt, although I'm not so sure -- I definitely don't need padding here and I'd have to care about what ivec and num are, and how I want to generate them... What am I missing?

    Read the article

  • Saving Email/Password to Keychain in iOS

    - by Jason
    I'm very new to iOS development so forgive me if this is a newbie question. I have a simple authentication mechanism for my app that takes a user's email address and password. I also have a switch that says 'Remember me'. If the user toggles that switch on, I'd like to preserve their email/password so those fields can be auto-populated in the future. I've gotten this to work with saving to a plist file but I know that's not the best idea since the password is unencrypted. I found some sample code for saving to the keychain, but to be honest, I'm a little lost. For the function below, I'm not sure how to call it and how to modify it to save the email address as well. I'm guessing to call it would be: saveString(@"passwordgoeshere"); Thank you for any help!!! + (void)saveString:(NSString *)inputString forKey:(NSString *)account { NSAssert(account != nil, @"Invalid account"); NSAssert(inputString != nil, @"Invalid string"); NSMutableDictionary *query = [NSMutableDictionary dictionary]; [query setObject:(id)kSecClassGenericPassword forKey:(id)kSecClass]; [query setObject:account forKey:(id)kSecAttrAccount]; [query setObject:(id)kSecAttrAccessibleWhenUnlocked forKey:(id)kSecAttrAccessible]; OSStatus error = SecItemCopyMatching((CFDictionaryRef)query, NULL); if (error == errSecSuccess) { // do update NSDictionary *attributesToUpdate = [NSDictionary dictionaryWithObject:[inputString dataUsingEncoding:NSUTF8StringEncoding] forKey:(id)kSecValueData]; error = SecItemUpdate((CFDictionaryRef)query, (CFDictionaryRef)attributesToUpdate); NSAssert1(error == errSecSuccess, @"SecItemUpdate failed: %d", error); } else if (error == errSecItemNotFound) { // do add [query setObject:[inputString dataUsingEncoding:NSUTF8StringEncoding] forKey:(id)kSecValueData]; error = SecItemAdd((CFDictionaryRef)query, NULL); NSAssert1(error == errSecSuccess, @"SecItemAdd failed: %d", error); } else { NSAssert1(NO, @"SecItemCopyMatching failed: %d", error); } }

    Read the article

  • Top n items in a List ( including duplicates )

    - by Krishnan
    Trying to find an efficient way to obtain the top N items in a very large list, possibly containing duplicates. I first tried sorting & slicing, which works. But this seems unnnecessary. You shouldn't need to sort a very large list if you just want the top 20 members. So I wrote a recursive routine which builds the top-n list. This also works, but is very much slower than the non-recursive one! Question: Which is my second routine (elite2) so much slower than elite, and how do I make it faster ? My code is attached below. Thanks. import scala.collection.SeqView import scala.math.min object X { def elite(s: SeqView[Int, List[Int]], k:Int):List[Int] = { s.sorted.reverse.force.slice(0,min(k,s.size)) } def elite2(s: SeqView[Int, List[Int]], k:Int, s2:List[Int]=Nil):List[Int] = { if( k == 0 || s.size == 0) s2.reverse else { val m = s.max val parts = s.force.partition(_==m) val whole = if( parts._1.size > 1) parts._1.tail:::parts._2 else parts._2 elite2( whole.view, k-1, m::s2 ) } } def main(args:Array[String]) = { val N = 1000000/3 val x = List(N to 1 by -1).flatten.map(x=>List(x,x,x)).flatten.view println(elite2(x,20)) println(elite(x,20)) } }

    Read the article

  • How can I achieve this kind of relationship (inheritance, composition, something else)?

    - by Tim
    I would like to set up a foundation of classes for an application, two of which are person and student. A person may or may not be a student and a student is always a person. The fact that a student “is a” person led me to try inheritance, but I can't see how to make it work in the case where I have a DAO that returns an instance of person and I then want to determine if that person is a student and call student related methods for it. class Person { private $_firstName; public function isStudent() { // figure out if this person is a student return true; // (or false) } } class Student extends Person { private $_gpa; public function getGpa() { // do something to retrieve this student's gpa return 4.0; // (or whatever it is) } } class SomeDaoThatReturnsPersonInstances { public function find() { return new Person(); } } $myPerson = SomeDaoThatReturnsPersonInstances::find(); if($myPerson->isStudent()) { echo 'My person\'s GPA is: ', $myPerson->getGpa(); } This obviously doesn't work, but what is the best way to achieve this effect? Composition doesn't sond right in my mind because a person does not “have a” student. I'm not looking for a solution necessarily but maybe just a term or phrase to search for. Since I'm not really sure what to call what I'm trying to do, I haven't had much luck. Thank you!

    Read the article

  • Dispose, when is it called?

    - by Snake
    Consider the following code: namespace DisposeTest { using System; class Program { static void Main(string[] args) { Console.WriteLine("Calling Test"); Test(); Console.WriteLine("Call to Test done"); } static void Test() { DisposeImplementation di = new DisposeImplementation(); } } internal class DisposeImplementation : IDisposable { ~DisposeImplementation() { Console.WriteLine("~ in DisposeImplementation instance called"); } public void Dispose() { Console.WriteLine("Dispose in DisposeImplementation instance called"); } } } The Dispose just never get's called, even if I put a wait loop after the Test(); invocation. So that quite sucks. I want to write a class that is straightforward and very easy to use, to make sure that every possible resource is cleaned up. I don't want to put that responsibilty to the user of my class. Possible solution: use using, or call Dispose myself(basicly the same). Can I force the user to use a using? Or can I force the dispose to be called? Calling GC.Collect(); after Test(); doesn't work either. Putting di to null doesn't invoke Dispose either. The Deconstructor DOES work, so the object get's deconstructed when it exits Test()

    Read the article

  • Accessing Sub functions /procedures from DPR or other function / procedure in Delphi

    - by HX_unbanned
    Hello, stackoverflowers :) As much I know - Subroutines are with Private access mode to its parent unction / procedure, right? Is there any way to access them from "outer-world" - dpr or other function / procedure in unit? Also - which way takes more calcualtion and space to compiled file? for example: function blablabla(parameter : tparameter) : abcde; procedure xyz(par_ : tpar_); begin // ... end; begin // ... end; procedure albalbalb(param : tparam) : www; begin xyz(par_ : tpar); // is there any way to make this function public / published to access it therefore enabling to call it this way? end; // all text is random. // also, is there way to call it from DPR in this manner? // in C++ this can be done by specifing access mode and/or using "Friend" class .. but in DELPHI?

    Read the article

  • Generic Singleton Fasade design pattern

    - by Paul
    Hi I try write singleton fasede pattern with generics. I have one problem, how can I call method from generic variable. Something like this: T1 t1 = new T1(); //call method from t1 t1.Method(); In method SingletonFasadeMethod I have compile error: Error 1 'T1' does not contain a definition for 'Method' and no extension method 'Method' accepting a first argument of type 'T1' could be found (are you missing a using directive or an assembly reference?) Any advace? Thank, I am beginner in C#. All code is here: namespace GenericSingletonFasade { public interface IMyInterface { string Method(); } internal class ClassA : IMyInterface { public string Method() { return " Calling MethodA "; } } internal class ClassB : IMyInterface { public string Method() { return " Calling MethodB "; } } internal class ClassC : IMyInterface { public string Method() { return "Calling MethodC"; } } internal class ClassD : IMyInterface { public string Method() { return "Calling MethodD"; } } public class SingletonFasade<T1,T2,T3> where T1 : class,new() where T2 : class,new() where T3 : class,new() { private static T1 t1; private static T2 t2; private static T3 t3; private SingletonFasade() { t1 = new T1(); t2 = new T2(); t3 = new T3(); } class SingletonCreator { static SingletonCreator() { } internal static readonly SingletonFasade<T1,T2,T3> uniqueInstace = new SingletonFasade<T1,T2,T3>(); } public static SingletonFasade<T1,T2,T3> UniqueInstace { get { return SingletonCreator.uniqueInstace; } } public string SingletonFasadeMethod() { //Problem is here return t1.Method() + t2.Method() + t3.Method(); } } }

    Read the article

  • Exposing a C++ API to C#

    - by Siyfion
    So what I have is a C++ API contained within a *.dll and I want to use a C# application to call methods within the API. So far I have created a C++ / CLR project that includes the native C++ API and managed to create a "bridge" class that looks a bit like the following: ManagedBridge.h namespace ManagedAPIWrapper { public ref class Bridge { public: int bridge_test(void); int bridge_test2(api_struct* temp); } } ManagedBridge.cpp int Bridge::bridge_test(void) { return test(); } int Bridge::bridge_test2(api_struct* temp) { return test2(temp); } I also have a C# application that has a reference to the C++/CLR "Bridge.dll" and then uses the methods contained within. I have a number of problems with this: I can't figure out how to call bridge_test2 within the C# program, as it has no knowledge of what a api_struct actually is. I know that I need to marshal the object somewhere, but do I do it in the C# program or the C++/CLR bridge? This seems like a very long-winded way of exposing all of the methods in the API, is there not an easier way that I'm missing out? (That doesn't use P/Invoke!)

    Read the article

  • C++: Calculate probability percentage during each iteration

    - by Mur Quirk
    Can't seem to get this to work. The idea is to calculate the percentage of heads and tails after each count, accumulating after each iteration. Except I keep getting nan% for my calculations. Anybody see what I'm doing wrong? void flipCoin(time_t seconds, int flipCount){ vector<int> flips; float headCount = 0; float tailCount = 0; double headProbability = double((headCount/(headCount + tailCount))*100); double tailProbability = double((tailCount/(headCount + tailCount))*100); for (int i=0; i < flipCount; i++) { int flip = rand() % (HEADS - TAILS + 1) + TAILS; flips.push_back(flip); if (flips[i] == 1) { tailCount++; cout << "Tail Percent: " << tailProbability << "%" << endl; }else{ headCount++; cout << "Head Percent: " << headProbability << "%" << endl; } } }

    Read the article

  • Python, lambda, find minimum

    - by qba
    I have foreach function which calls specified function on every element which it contains. I want to get minimum from thise elements but I have no idea how to write lambda or function or even a class that would manage that. Thanks for every help. I use my foreach function like this: o.foreach( lambda i: i.call() ) or o.foreach( I.call ) I don't like to make a lists or other objects. I want to iterate trough it and find min. I manage to write a class that do the think but there should be some better solution than that: class Min: def __init__(self,i): self.i = i def get_min(self): return self.i def set_val(self,o): if o.val < self.i: self.i = o.val m = Min( xmin ) self.foreach( m.set_val ) xmin = m.get_min() Ok, so I suppose that my .foreach method is non-python idea. I should do my Class iterable because all your solutions are based on lists and then everything will become easier. In C# there would be no problem with lambda function like that, so I though that python is also that powerful.

    Read the article

  • Javascript object properties access functions in parent constructor?

    - by Bob Spryn
    So I'm using this pretty standard jquery plugin pattern whereby you can grab an api after applying the jquery function to a specific instance. This API is essentially a javascript object with a bunch of methods and data. So I wanted to essentially create some private internal methods for the object only to manipulate data etc, which just doesn't need to be available as part of the API. So I tried this: // API returned with new $.TranslationUI(options, container) $.TranslationUI = function (options, container) { // private function? function monkey(){ console.log("blah blah blah"); } // extend the default settings with the options object passed this.settings = $.extend({},$.TranslationUI.defaultSettings,options); // set a reference for the container dom element this.container = container; // call the init function this.init(); }; The problem I'm running into is that init can't call that function "monkey". I'm not understanding the explanation behind why it can't. Is it because init is a prototype method?($.TranslationUI's prototype is extended with a bunch of methods including init elsewhere in the code) $.extend($.TranslationUI, { prototype: { init : function(){ // doesn't work monkey(); // editing flag this.editing = false; // init event delegates here for // languagepicker $(this.settings.languageSelector, this.container).bind("click", {self: this}, this.selectLanguage); } } }); Any explanations would be helpful. Would love other thoughts on creating private methods with this model too. These particular functions don't HAVE to be in prototype, and I don't NEED private methods protected from being used externally, but I want to know how should I have that requirement in the future.

    Read the article

  • What's this UI pattern called?

    - by Bears will eat you
    I'm trying to figure out what this sort of thing is called, and eventually how I can create one in a web browser. It looks like this (screenshot of the first app that came to mind): The specific component/pattern I'm looking for is the two list boxes ("Included Gear" and "Excluded Gear") that represent inclusion/exclusion of items from a set. I'm not really looking for the WPF name (if there is one) but it might be helpful. I am looking for the name of this thingy, if there is one, and if you really want to make my day, you can point me toward a jQuery or YUI way of making one of these dealies in a browser. In case you were wondering, the screenshot is a World of Warcraft gear optimization program. Go figure why it was the first program that came to mind when I was trying to think of an example.

    Read the article

  • How to access parents' members from a inner class in WPF?

    - by black sensei
    Hello Experts! I'm trying to do scheduled operation let's say to check for user's credit left via web service call and update the user interface. i've tried with quartz.net to implement the scheduling bit.i created an inner class in the window class i need to update.That inner class has the method that calls the webservice and the result needs to be displayed back to the UI. here is an example of what i did. public partial class Window2 : Window { private int i; public Window2() { InitializeComponent(); } public class Myclass :IJob { public void Execute(JobExecutionContext context) { string result = doMyOperation(); //i'll like to call parent label member of name lblNotif //is something like parent.lblNotif.Content = result; //possible? } public string doMyOperation() { //calling the wermethod to retreive user's balance return result = service.GetUsersBalace(user); } } } Well the quartz bit is working and this post is not about quartz. here are my questions Question 1 : How is it possible to access Window2 controls, for instace lable lblNotif? Question 2 : If my thinking about this is wrong, what is done as best practice to solve my kind of problem, where an application need to do an operation let's say every 5mn and update the the UI. Question 3 : i at first tried to use the backgroundworker and i felt like i can't do the scheduling bit with it.Is that correct or i'm wrong. thanks for those who commented already and sorry for those who didn't get the meaning of my post.I hope this will be a bit clearer.Thanks for reading

    Read the article

  • How do I display core data on second view controller?

    - by jon
    I am working on my first core data iPhone application. I am using a navigation controller, and the root view controller displays 4 rows. Clicking the first row takes me to a second table view controller. However, when I click the back button, repeat the row tap, click the back button again, and tap the row a third time, I get an error. I have been researching this for a week with no success. I can reproduce the error easily: Create a new Navigation-based Application, use Core Data for storage, call it MyTest which creates MyTestAppDelegate and RootViewController. Add new UIViewController subclass, with UITableViewController and xib, call it ListViewController. Copy code from RootViewController.h and .m to ListViewController.h and .m., changing the file names appropriately. To simplify the code, I removed the trailing “_” from all variables. In RootViewController, I added #import ListViewController.h, set up an array to display 4 rows and navigate to ListViewController when clicking the first row. In ListViewController.m, I added #import MyTestAppDelegate.h” and the following code: - (void)viewDidLoad { [super viewDidLoad]; if (managedObjectContext == nil) { managedObjectContext = [(MyTestAppDelegate *)[[UIApplication sharedApplication] delegate] managedObjectContext]; } .. } The sequence that causes the error is tap row, return, tap row, return, tap row - error. managedObjectContext is synthesized for the third time. I appreciate your patience and your help, as this makes no sense to me. ADDENDUM: I may have a partial solution. http://www.iphonedevsdk.com/forum/iphone-sdk-development/41688-accessing-app-delegates-managed-object-context.html If I do not release the managedObjectContext in the .m file, the error goes away. Is that ok or will that cause me issues? - (void)dealloc { [fetchedResultsController release]; // [managedObjectContext release]; [super dealloc]; } ADDENDUM 2: See solution below. Sorry for the formatting issues - this was my first post.

    Read the article

  • Generics Java and Shadowing of type parameters

    - by rubixibuc
    This code seems to work fine class Rule<T> { public <T>Rule(T t) { } public <T> void Foo(T t) { } } Does the method type parameter shadow the class type parameter? Also when you create an object does it use the type parameter of the class? example Rule<String> r = new Rule<String>(); Does this normally apply to the type parameter of the class, in the situation where they do not conflict? I mean when only the class has a type parameter, not the constructor, or does this look for a type parameter in the constructor? If they do conflict how does this change? SEE DISCUSSION BELOW if I have a function call x = <Type Parameter>method(); // this is a syntax error even inside the function or class ; I must place a this before it, why is this, and does everything still hold true. Why don't I need to prefix anything for the constructor call. Shouldn't Oracle fix this.

    Read the article

  • Need help in sorting the programming buzz-words

    - by cwap
    How do you sort out the good buzz from the bad buzz? - I really need your help here :) I see a lot of buzz-words nowadays, both here on SO and in school. For example, we had a teacher who everyone respected, who said "be careful about gold-plating and death-by-interfacing". Now, everyone and their mama cries whenever I'm creating an interface.. Another example would be here on SO where lately "premature optimization is the root of all evil", so everytime someone asks a perfomance question, he'll get that sentence thrown in his face. A few months ago I remember it was all about NHibernate in here, etc., etc... These things comes and goes, but only the good buzz stays. Now, how do you seperate the good from the bad? By reading blogs from respected persons? By trying to come to a conclusion on your own, and then try to convince others that you're right? By simply ignoring it?

    Read the article

  • Trigger alert when database entries are added, not when they are removed

    - by Jeremy
    I have a jQuery script running that makes a periodic AJAX call using the following code. var a = moment(); var dayOfMonth = a.format("MMM Do"); var timeSubmitted = a.format("h:mm a"); var count_cases = -1; var count_claimed = -1; setInterval(function(){ //check if new lead was added to the db $.ajax({ type : "POST", url : "inc/new_lead_alerts_process.php", dataType: 'json', cache: false, success : function(response){ $.getJSON("inc/new_lead_alerts_process.php", function(data) { if (count_cases != -1 && count_cases != data.count) { window.location = "new_lead_alerts.php?id="+data.id; } count_cases = data.count; }); } }); This is the PHP that runs with each call: $count = mysql_fetch_array(mysql_query("SELECT count(*) as count FROM leads")); $client_id = mysql_fetch_array(mysql_query("SELECT id, client_id FROM leads ORDER BY id DESC LIMIT 1")); echo json_encode(array("count" => $count['count'], "id" => $client_id['id'], "client_id" => $client_id['client_id'])); I need to change the code so that the alert only triggers when a new entry is added to the database, not when an existing entry is removed. As it stands, the alert fires on both events. Any help is greatly appreciated.

    Read the article

  • how to use q.js promises to work with multiple asynchronous operations

    - by kimsia
    Note: This question is also cross-posted in Q.js mailing list over here. i had a situation with multiple asynchronous operations and the answer I accepted pointed out that using Promises using a library such as q.js would be more beneficial. I am convinced to refactor my code to use Promises but because the code is pretty long, i have trimmed the irrelevant portions and exported the crucial parts into a separate repo. The repo is here and the most important file is this. The requirement is that I want pageSizes to be non-empty after traversing all the dragged'n dropped files. The problem is that the FileAPI operations inside getSizeSettingsFromPage function causes getSizeSettingsFromPage to be async. So I cannot place checkWhenReady(); like this. function traverseFiles() { for (var i=0, l=pages.length; i<l; i++) { getSizeSettingsFromPage(pages[i], calculateRatio); } checkWhenReady(); // this always returns 0. } This works, but it is not ideal. I prefer to call checkWhenReady just ONCE after all the pages have undergone this function calculateRatio successfully. function calculateRatio(width, height, filename) { // .... code pageSizes.add(filename, object); checkWhenReady(); // this works but it is not ideal. I prefer to call this method AFTER all the `pages` have undergone calculateRatio // ..... more code... } How do I refactor the code to make use of Promises in Q.js?

    Read the article

  • destructor being called by subclass

    - by zero
    I'm currently learning more about php objects and constructors/destructors, but i've noticed in my code that the parent class's destructor is being called twice, I thought it was because i was extending the first class to my second class and that the second class was calling it, but this is what the php docs say about that: Like constructors, parent destructors will not be called implicitly by the engine. In order to run a parent destructor, one would have to explicitly call parent::__destruct() in the destructor body. so if it is not being called by the subclass then is it because by extended the first class that i've made a reference to the parent class making it call itself twice or I'm I way off base here? the code: <?php class test{ public $test1 = "this is a test of a pulic property"; private $test2 = "this is a test of a private property"; protected $test3 = "this is a test of a protected property"; const hello = 900000; function __construct($h){ //echo 'this is the constructor test '.$h; } function x($x2){ echo ' this is fn x'.$x2; } function y(){ print "this is fn y"; } } $obj = new test("this is an \"arg\" sent to instance of test"); class hey extends test{ function hey(){ $this->x('<br>from the host with the most'); echo ' <br>from hey class'.$this->test3; } } $obj2 = new hey(); echo $obj2::hello; ?>

    Read the article

< Previous Page | 420 421 422 423 424 425 426 427 428 429 430 431  | Next Page >