Search Results

Search found 41535 results on 1662 pages for 'method reference'.

Page 170/1662 | < Previous Page | 166 167 168 169 170 171 172 173 174 175 176 177  | Next Page >

  • Is it possible to overwrite a static method in parent class?

    - by MartinDenny2069
    I have a static method defined in a base class, I want to overwrite this method in its child class, is it possible? I tried this but it did not work as I expected. When I created an instance of class B and invoke its callMe() method, the static foo() method in class A is invoked. public abstract class A { public static void foo() { System.out.println("I am base class"); } public void callMe() { foo(); } } Public class B { public static void foo() { System.out.println("I am child class"); } }

    Read the article

  • How to get a reference to a control in the view?

    - by Kevin
    If I have a UIScrollView set up in the view via the Interface Builder, how do I get a reference to it in the ViewController implementation? I want to programmatically add labels to the scroll view. For example, in C# if you have a textbox declared in the UI/form, you can access it by simply using the ID declared for that textbox. It doesn't seem this simple in objective c. Thanks Kevin

    Read the article

  • Passing List (Of ChildClass) as parameter to method expecting List (Of ParentClass)?

    - by Nicholas
    Hi, I have implemented inheritance for two parent classes called Table and Field. Each parent class has several child classes. In the Table parent class, I created a method that expects parameter List(Of Field). I get an error when trying to pass in parameter List(Of ChildField) to the method that expects a parameter of List(Of Field). The error message is as below: Value of type 'System.Collections.Generic.List(Of com.hlb.icisbatch.data.ChildField)' cannot be converted to 'System.Collections.Generic.List(Of com.hlb.icisbatch.data.Field)' My question, is it possible to pass in list of child class as parameter? If it is not a list then it works fine. But somehow it is not possible with lists? Below is sample class structure: Table Field | | ChildTable ChildField I have a method in the parent class: Public Class Table Public Sub New() End Sub Public Overridable Sub setFields(ByVal list As List(Of Field) 'Do work here' End Sub End Class and method in child class: Public Class ChildTable Public Sub New(ByVal list As List(Of ChildField) setFields(ChildField) End Sub End Class

    Read the article

  • How do I pass a reference type to Control.Invoke / display a form centered on the main form

    - by Rubio
    I'm on a thread other than the UI thread and need to display a modal form that's centered on the application's main form. What I usually do is use the width and height of the main form and the modal form to calculate the location, then use the PointToScreen method of the main form to get the location of the modal form. Since I'm on another thread I need to use Control.Invoke to call this method. I just can't figure out how to pass a parameter of type Point to Control.Invoke (params object[]). Value types and String works fine. Or, if someone can find a better way to display a form centered on the main form regardless of thread, that would be great. MessageBox seems to be able to do this (although not modally).

    Read the article

  • When is it better to use a method versus a property for a class definition?

    - by ccomet
    Partially related to an earlier question of mine, I have a system in which I have to store complex data as a string. Instead of parsing these strings as all kinds of separate objects, I just created one class that contains all of those objects, and it has some parser logic that will encode all properties into strings, or decode a string to get those objects. That's all fine and good. This question is not about the parser itself, but about where I should house the logic for the parser. Is it a better choice to put it as a property, or as a method? In the case of a property, say public string DataAsString, the get accessor would house the logic to encode all of the data into a string, while the set accessor would decode the input value and set all of the data in the class instance. It seems convenient because the input/output is indeed a string. In the case of a method, one method would be Encode(), which returns the encoded string. Then, either the constructor itself would house the logic for the decoding a string and require the string argument, or I write a Decode(string str) method which is called separately. In either case, it would be using a method instead of a property. So, is there a functional difference between these paths, in terms of the actual running of the code? Or are they basically equivalent and it then boils down to a choice of personal preference or which one looks better? And in that kind of question... which would look cleaner anyway?

    Read the article

  • Django: Setting up database code tables (aka reference tables, domain tables)?

    - by User
    Often times applications will need some database code tables (aka reference tables or domain tables or lookup tables). Suppose I have a model class called Status with a field called name that could hold values like: Canceled Pending InProgress Complete Where and at what point would I setup these values in Django? Its like a one time operation to setup these values in the database. Infrequently, these values could be added to.

    Read the article

  • how to call any method of Project from classlibrary?

    - by Pankaj Mishra
    Hello I have Class Library Where a class of multithreading Of Producer and consumer based. private void WorkDeQueue() { while (true) { string Url = null; lock (locker) { if (queueList.Count > 0) { Url = queueList.Dequeue(); /* return if a null is found in the queue */ if (Url == null) return; } } if (Url != null) { /* if a job was found then process it */ GetData(Url); //This Is a Method } else { /* if a job was not found (meaning list is empty) then * wait till something is added to it*/ wh.WaitOne(); } } } this GetData method has no body on that class. How can i call any method of my project in palace of getdata. I tried with factory Pattern and also with reflection. but both didn't worked for me. So plz tell me how can i call any method of my project from here.

    Read the article

  • is there difference between debug and release reference path while compiling?

    - by Nair
    I am building a SL3 + RIA application in VS2008. When compiled the application in debug mode it compiles fine with out any error, but when I compile the same application with out any code change in release mode I get an error 'The type of namespace name 'BusyIndicator' does not exist in the namespace 'System.Windows.Controls' (are you missing an assembly reference). All the errors are coming from the generated code name.g.cs Just curious anyone run into this problem.

    Read the article

  • How do I track the method the user is looking at in VS 2010 IDE as an Addin

    - by Rob
    I have been wandering around the object model for VS 2010 and haven't been able to work out the best method for watching what the user is looking at in the main edit window. I know that each Class/method/property is broken down into its own . What I would ideally like is to hook to an event which says "The user has moved the cursor onto Project.Class.Method" and ideally "and is looking at line 4". Any suggestions?

    Read the article

  • When should I use static methods in a class and what are the benefits?

    - by NAVEED
    I have concept of static variables but what are the benefits of static methods in a class. I have worked on some projects but I did not make a method static. Whenever I need to call a method of a class, I create an object of that class and call the desired method. Static variable in a method holds it's value even when method is executed but accessible only in its containing method but what is the best definition of static method? Is calling the static method without creating object of that class is the only benefit of static method? What is the accessible range for static method? What is the syntax to create and calling static method in php? Thanks

    Read the article

  • Refactor throwing not null exception if using a method that has a dependency on a certain contructor

    - by N00b
    In the method below the second constructor accepts a ForumThread object which the IncrementViewCount() method uses. There is a dependency between the method and that particular constructor. Without extracting into a new private method the null check in IncrementViewCount() and LockForumThread() (plus other methods not shown) is there some simpler re-factoring I can do or the implementation of a better design practice for this method to guard against the use of the wrong constructor with these dependent methods? Thank you for any suggestions in advance. private readonly IThread _forumLogic; private readonly ForumThread _ft; public ThreadLogic(IThread forumLogic) : this(forumLogic, null) { } public ThreadLogic(IThread forumLogic, ForumThread ft) { _forumLogic = forumLogic; _ft = ft; } public void Create(ForumThread ft) { _forumLogic.SaveThread(ft); } public void IncrementViewCount() { if (_ft == null) throw new NoNullAllowedException("_ft ForumThread is null; this must be set in the constructor"); lock (_ft) { _ft.ViewCount = _ft.ViewCount + 1; _forumLogic.SaveThread(_ft); } } public void LockForumThread() { if (_ft == null) throw new NoNullAllowedException("_ft ForumThread is null; this must be set in the constructor"); _ft.ThreadLocked = true; _forumLogic.SaveThread(_ft); }

    Read the article

  • polymorphism, inheritance in c# - base class calling overridden method?

    - by Andrew Johns
    This code doesn't work, but hopefully you'll get what I'm trying to achieve here. I've got a Money class, which I've taken from http://www.noticeablydifferent.com/CodeSamples/Money.aspx, and extended it a little to include currency conversion. The implementation for the actual conversion rate could be different in each project, so I decided to move the actual method for retrieving a conversion rate (GetCurrencyConversionRate) into a derived class, but the ConvertTo method contains code that would work for any implementation assuming the derived class has overriden GetCurrencyConversionRate so it made sense to me to keep it in the parent class? So what I'm trying to do is get an instance of SubMoney, and be able to call the .ConvertTo() method, which would in turn use the overriden GetCurrencyConversionRate, and return a new instance of SubMoney. The problem is, I'm not really understanding some concepts of polymorphism and inheritance yet, so not quite sure what I'm trying to do is even possible in the way I think it is, as what is currently happening is that I end up with an Exception where it has used the base GetCurrencyConversionRate method instead of the derived one. Something tells me I need to move the ConvertTo method down to the derived class, but this seems like I'll be duplicating code in multiple implementations, so surely there's a better way? public class Money { public CurrencyConversionRate { get { return GetCurrencyConversionRate(_regionInfo.ISOCurrencySymbol); } } public static decimal GetCurrencyConversionRate(string isoCurrencySymbol) { throw new Exception("Must override this method if you wish to use it."); } public Money ConvertTo(string cultureName) { // convert to base USD first by dividing current amount by it's exchange rate. Money someMoney = this; decimal conversionRate = this.CurrencyConversionRate; decimal convertedUSDAmount = Money.Divide(someMoney, conversionRate).Amount; // now convert to new currency CultureInfo cultureInfo = new CultureInfo(cultureName); RegionInfo regionInfo = new RegionInfo(cultureInfo.LCID); conversionRate = GetCurrencyConversionRate(regionInfo.ISOCurrencySymbol); decimal convertedAmount = convertedUSDAmount * conversionRate; Money convertedMoney = new Money(convertedAmount, cultureName); return convertedMoney; } } public class SubMoney { public SubMoney(decimal amount, string cultureName) : base(amount, cultureName) {} public static new decimal GetCurrencyConversionRate(string isoCurrencySymbol) { // This would get the conversion rate from some web or database source decimal result = new Decimal(2); return result; } }

    Read the article

  • How to make a request from an android app that can enter a Spring Security secured webservice method

    - by johnrock
    I have a Spring Security (form based authentication) web app running CXF JAX-RS webservices and I am trying to connect to this webservice from an Android app that can be authenticated on a per user basis. Currently, when I add an @Secured annotation to my webservice method all requests to this method are denied. I have tried to pass in credentials of a valid user/password (that currently exists in the Spring Security based web app and can log in to the web app successfully) from the android call but the request still fails to enter this method when the @Secured annotation is present. The SecurityContext parameter returns null when calling getUserPrincipal(). How can I make a request from an android app that can enter a Spring Security secured webservice method? Here is the code I am working with at the moment: Android call: httpclient.getCredentialsProvider().setCredentials( //new AuthScope("192.168.1.101", 80), new AuthScope(null, -1), new UsernamePasswordCredentials("joeuser", "mypassword")); String userAgent = "Android/" + getVersion(); HttpGet httpget = new HttpGet(MY_URI); httpget.setHeader("User-Agent", userAgent); httpget.setHeader("Content-Type", "application/xml"); HttpResponse response; try { response = httpclient.execute(httpget); HttpEntity entity = response.getEntity(); ... parse xml Webservice Method: @GET @Path("/payload") @Produces("application/XML") @Secured({"ROLE_USER","ROLE_ADMIN","ROLE_GUEST"}) public Response makePayload(@Context Request request, @Context SecurityContext securityContext){ Payload payload = new Payload(); payload.setUsersOnline(new Long(200)); if (payload == null) { return Response.noContent().build(); } else{ return Response.ok().entity(payload).build(); } }

    Read the article

  • Adding a reference to a css file in an ascx file in vs2008 only to get intellisense

    - by Nick Allen - Tungle139
    Normally visual studio brings up intellisense for available css classes, which it draws from css files linked to the current aspx/master document. Is there a way to get this to work in an ascx file in a similar way to referencing external JavaScript files in js files for the purpose of intellisense /// <reference path="jquery-1.4.1.js" /> I only want this for the purpose of intellisense and not getting squiggly lines under un-recognised classes. My css files will be actually linked from the aspx/master page.

    Read the article

  • Is a call to the following method considered late binding?

    - by AspOnMyNet
    1) Assume: • B1 defines methods virtualM() and nonvirtualM(), where former method is virtual while the latter is non-virtual • B2 derives from B1 • B2 overrides virtualM() • B2 is defined inside assembly A • Application app doesn’t have a reference to assembly A In the following code application app dynamically loads an assembly A, creates an instance of a type B2 and calls methods virtualM() and nonvirtualM(): Assembly a=Assembly.Load(“A”); Type t= a.GetType(“B2”); B1 a = ( B1 ) Activator.CreateInstance ( “t” ); a.virtualM(); a.nonvirtualM(); a) Is call to a.virtualM() considered early binding or late binding? b) I assume a call to a.nonvirtualM() is resolved during compilation time? 2) Does the term late binding refer only to looking up the target method at run time or does it also refer to creating an instance of given type at runtime? thanx EDIT: 1) A a=new A(); a.M(); As far as I know, it is not known at compile time where on the heap (thus at which memory address ) will instance a be created during runtime. Now, with early binding the function calls are replaced with memory addresses during compilation process. But how can compiler replace function call with memory address, if it doesn’t know where on the heap will object a be created during runtime ( here I’m assuming the address of method a.M will also be at same memory location as a )? 2) The method slot is determined at compile time I assume that by method slot you’re referring to the entry point in V-table?

    Read the article

  • Is it safe to put reference to current user in User model in Rails?

    - by Art Shayderov
    You know, I think I have to check current user in the model callbacks (like before_update). Rather than rely solely on adding where ('something.user_id = ?', 'current_user.id') in the controllers. I need something like Thread.CurrentPrincipal in .NET Is it safe to put reference to current user in User model? I'm sorry I don't really understand how it works under the hood yet. Or how you do it The Rails way? Sorry if this a silly question.

    Read the article

  • JNI cached jclass global reference variables being garbage collected?

    - by bubbadoughball
    I'm working in the JNI Invocation API, calling into Java from C. I have some upfront initialization to cache 30+ Java classes into global references. The results of FindClass are passed into NewGlobalRef to acquire a global reference to the class. I'm caching these class variables to reuse them later. I have 30+ global references to classes (and 30+ global methodIDs for the class constructors). In the following sample, I've removed exception handling as well as JNI invocation for the purpose of shortening the code snippet. My working code has exception checks after every JNI call and I'm running with -Xcheck:jni. Here's the snippet: jclass aClass; jclass bClass; jmethodID aCtor; jmethodID bCtor; void getGlobalRef(const char* clazz, jclass* globalClass) { jclass local = (*jenv)->FindClass(jenv,clazz); if (local) { *globalClass = (jclass) (*jenv)->NewGlobalRef(jenv,local); (*jenv)->DeleteLocalRef(jenv,local); } } methodID getMethodID(jclass clazz, const char* method, const char* sig) { return (*jenv)->GetMethodID(jenv,clazz,method,sig); } void initializeJNI() { getGlobalRef("MyProj/Testclass1", &aclass); getGlobalRef("MyProj/Testclass2", &bclass); . . aCtor = getMethodID(aclass,"<init>","()V"); bCtor = getMethodID(bclass,"<init>","(I)V"); } The initializeJNI() function sets the global references for jclasses and method IDs for constructors as well as some jfieldID's and some initialization of C data structures. After initialization, when I call into a JNI function using some of the cached jclasses and ctor jmethodIDs, I get a bad global or local reference calling reported from the -Xcheck:jni. In gdb, I break at the last line of initializeJNI(), and print all jclasses and jmethodIDs and the ones causing problems look to have been turned into garbage or garbage-collected (i.e. 0x00 or 0x06). Is it possible for global references to be gc'ed? Any suggestions?

    Read the article

< Previous Page | 166 167 168 169 170 171 172 173 174 175 176 177  | Next Page >