Search Results

Search found 45436 results on 1818 pages for 'singleton class'.

Page 24/1818 | < Previous Page | 20 21 22 23 24 25 26 27 28 29 30 31  | Next Page >

  • Access property from include inside a class method in PHP

    - by Jojo
    How do you make a class property available to the other included file inside the same class' method? // file A.php class A { private $var = 1; public function go() { include('another.php'); } } in another file: // this is another.php file // how can I access class A->var? echo $var; // this can't be right Is this possible given the scope. If var is an array then we can use extract but if var is not, we can wrap it in an array. Is there a better way? Thanks!

    Read the article

  • Rails: i have a class method and i want to modify something of the instance

    - by Totty
    Rails: i have a class method and i want to modify something of the instance something like this: class Test < Main template :box def test # here I want to access the template name, that is box end end class Main def initialize end def self.template(name) # here I have to save somehow the template name # remember is not an instance. end end that is similar to the model classes: # in the model has_many :projects How do I do it?

    Read the article

  • Can You Have "Empty" Abstract/Classes?

    - by ShrimpCrackers
    Of course you can, I'm just wondering if it's rational to design in such a way. I'm making a breakout clone and was doing some class design. I wanted to use inheritance, even though I don't have to, to apply what I've learned in C++. I was thinking about class design and came up with something like this: GameObject - base class (consists of data members like x and y offsets, and a vector of SDL_Surface* MovableObject : GameObject - abstract class + derived class of GameObject (one method void move() = 0; ) NonMovableObject : GameObject - empty class...no methods or data members other than constructor and destructor(at least for now?). Later I was planning to derive a class from NonMovableObject, like Tileset : NonMovableObject. I was just wondering if "empty" abstract classes or just empty classes are often used...I notice that the way I'm doing this, I'm just creating the class NonMovableObject just for sake of categorization. I know I'm overthinking things just to make a breakout clone, but my focus is less on the game and more on using inheritance and designing some sort of game framework.

    Read the article

  • Is there a name for a mini class that is not a struct?

    - by user1555300
    I have a couple of mini-classes that are not nested classes. They need to be passed around between different larger classes to use. In a way, they act like Tuples, storing fields in them. For example, [Serializable] public class TransformObject { public GameObject GameObj; public tk2dCameraAnchor Anchor; public ManagerTransform MTransform; } I have a few of them for my game I have been developing. They have to be classes, not struct because the Unity3d editor will not show in the inspector if so. I was just wondering if there is a official name for these kind of mini classes.

    Read the article

  • Create inherited class from base class

    - by Raj
    public class Car { private string make; private string model; public Car(string make, string model) { this.make = make; this.model = model; } public virtual void Display() { Console.WriteLine("Make: {0}", make); Console.WriteLine("Model: {0}", model); } public string Make { get{return make;} set{make = value;} } public string Model { get{return model;} set{model = value;} } } public class SuperCar:Car { private Car car; private int horsePower; public SuperCar(Car car) { this.car = car; } public int HorsePower { get{return horsePower;} set{horsepower = value;} } public override void Display() { base.Display(); Console.WriteLine("I am a super car"); } When I do something like Car myCar = new Car("Porsche", "911"); SuperCar mySupcar = new SuperCar(myCar); mySupcar.Display(); I only get "I am a supercar" but not the properties of my base class. Should I explicitly assign the properties of my base class in the SuperCar constructor? In fact I'm trying Decorator pattern where I want a class to add behaviour to a base class.

    Read the article

  • Python: Class factory using user input as class names

    - by Sano98
    Hi everyone, I want to add class atttributes to a superclass dynamically. Furthermore, I want to create classes that inherit from this superclass dynamically, and the name of those subclasses should depend on user input. There is a superclass "Unit", to which I can add attributes at runtime. This already works. def add_attr (cls, name, value): setattr(cls, name, value) class Unit(object): pass class Archer(Unit): pass myArcher = Archer() add_attr(Unit, 'strength', 5) print "Strenght ofmyarcher: " + str(myArcher.strength) Archer.strength = 2 print "Strenght ofmyarcher: " + str(myArcher.strength) This leads to the desired output: Strenght ofmyarcher: 5 Strenght ofmyarcher: 2 But now I don't want to predefine the subclass Archer, but I'd rather let the user decide how to call this subclass. I've tried something like this: class Meta(type, subclassname): def __new__(cls, subclassname, bases, dct): return type.__new__(cls, subclassname, Unit, dct) factory = Meta() factory.__new__("Soldier") but no luck. I guess I haven't really understood what new does here. What I want as a result here is class Soldier(Unit): pass being created by the factory. And if I call the factory with the argument "Knight", I'd like a class Knight, subclass of Unit, to be created. Any ideas? Many thanks in advance! Bye -Sano

    Read the article

  • A dynamic array of class "landmark", inside another single class "landmarks"

    - by pinnacler
    I'm working on a robot localization simulator and I created a class called "landmark". The end result is going to be a robot that is always centered and always faces the top of the screen. As it turns, the birds eye view map will rotate around the robot. To accomplish this, I'm assuming I can rotate one class and have all elements inside rotate as well. So, the landmark class has properties x,y, label, and radius. This is suppose to simulate a tree location in a forest. To test everything, I need "forest data," and I wrote a script to generate 100 trees in a 100m x 100m area. The script automatically generates values within an acceptable range for x,y, radius. The generated data is stored in an object called tempForest and is 100x3. Ideally, I want to create a class called "landmarks" (plural) that has 100 landmark instances inside. How would I instantiate 100 instances of landmark in one instance of landmarks using that randomly generated data? Ideally, I'd just type treeBeacons = landmarks(); and it would randomly populate 100 (user definable, set in config file) instances with x, y, radius data. I'm not sure how to deal with a dynamic array of class "Landmark", inside another single class "landmarks." Any ideas?

    Read the article

  • Why does a sub-class class of a class have to be static in order to initialize the sub-class in the

    - by Alex
    So, the question is more or less as I wrote. I understand that it's probably not clear at all so I'll give an example. I have class Tree and in it there is the class Node, and the empty constructor of Tree is written: public class RBTree { private RBNode head; public RBTree(RBNode head,RBTree leftT,RBTree rightT){ this.head=head; this.head.leftT.head.father = head; this.head.rightT.head.father = head; } public RBTree(RBNode head){ this(head,new RBTree(),new RBTree()); } public RBTree(){ this(new RBNode(),null,null); } public class RBNode{ private int value; private boolean isBlack; private RBNode father; private RBTree leftT; private RBTree rightT; } } Eclipse gives me the error: "No enclosing instance of type RBTree is available due to some intermediate constructor invocation" for the "new RBTree()" in the empty constructor. However, if I change the RBNode to be a static class, there is no problem. So why is it working when the class is static. BTW, I found an easy solution for the cunstructor: public RBTree(){ this.head = new RBNode(); } So, I have no idea what is the problem in the first piece of code.

    Read the article

  • C# class can not disguise to be another class because GetType method cannot be override

    - by zinking
    there is a statement in the CLR via C# saying in C#, one class cannot disguise to be another, because GetType is virutal and thus it cannot be override but I think in C# we can still hide the parent implementation of GetType. I must missed something if I hide the base GetType implementation then I can disguise my class to be another class, is that correct? The key here is not whether GetType is virutal or not, the question is can we disguise one class to be another in C# Following is the NO.4 answer from the possible duplicate, so My question is more on this. is this kind of disguise possible, if so, how can we say that we can prevent class type disguise in C# ? regardless of the GetType is virtual or not While its true that you cannot override the object.GetType() method, you can use "new" to overload it completely, thereby spoofing another known type. This is interesting, however, I haven't figured out how to create an instance of the "Type" object from scratch, so the example below pretends to be another type. public class NotAString { private string m_RealString = string.Empty; public new Type GetType() { return m_RealString.GetType(); } } After creating an instance of this, (new NotAString()).GetType(), will indeed return the type for a string. share|edit|flag answered Mar 15 at 18:39 Dr Snooze 213 By almost anything that looks at GetType has an instance of object, or at the very least some base type that they control or can reason about. If you already have an instance of the most derived type then there is no need to call GetType on it. The point is as long as someone uses GetType on an object they can be sure it's the system's implementation, not any other custom definition. – Servy Mar 15 at 18:54 add comment

    Read the article

  • Java: Comparing a class with another within that class using a my own .equals

    - by user1670252
    I am making a method .equals replacing the equals method used. It accepts a object. I want it to check if that object equals the class that runs the .equals class. I know I want to compare all the private methods I have to that object. Is there a way to do this without making another private class to get the private variables from the object? How do I do this to compare equality not identity? I am stuck on this. Do i have to use == to compare? Also looking online i see others use recursion. If this is the way i have to do it can you show and explain it to me? so an example i have public boolean equals(Object o) { this is in a class we will call bobtheBuilder (first thing to pop in my head) I want to check if the object o is equal to the class he has private object array and a private int. I assume I want to check if the array and int of this class equal the array and int of the object.

    Read the article

  • static member specialization of templated child class and templated base class

    - by b3nj1
    I'm trying to have a templated class (here C) that inherits from another templated class (here A) and perform static member specialization (of int var here), but I cant get the right syntax to do so (if it's possible #include <iostream> template<typename derived> class A { public: static int var; }; //This one works fine class B :public A<B> { public: B() { std::cout << var << std::endl; } }; template<> int A<B>::var = 9; //This one doesn't works template<typename type> class C :public A<C<type> > { public: C() { std::cout << var << std::endl; } }; //template<> template<typename type> int A<C<type> >::a = 10; int main() { B b; C<int> c; return 0; } I put an example that works with a non templated class (here B) and i can get the static member specialization of var, but for C that just doesn't work. Here is what gcc tells me : test.cpp: In constructor ‘C<type>::C()’: test.cpp:29:26: error: ‘var’ was not declared in this scope test.cpp: At global scope: test.cpp:34:18: error: template definition of non-template ‘int A<C<type> >::a’ I'm using gcc version 4.6.3, thanks for any help

    Read the article

  • Outer class jframe is not hiding when calling the inner class jframe

    - by user2909960
    When i am calling the inner jframe, it is called, but outer jframe is not hiding. instead it gets overlapped. so what will be the solution for this. Is there any way to get out of this. As i tried when i am calling the inner class frame, the outer class frame is also called, and it is not hidden. package com.exp.example; import java.awt.Color; import java.awt.Container; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JTextField; @SuppressWarnings("serial") public class A extends JFrame implements ActionListener { JFrame rframe = new JFrame(); JLabel CFirstName; JTextField Cfname; JButton jbsubmit; Container cp; public A() { rframe.setSize(500, 200); rframe.setLocationRelativeTo(null); cp = getContentPane(); cp.setLayout(null); setSize(550, 300); rframe.setTitle("Outer Frame"); cp.setBackground(new Color(140, 180, 180)); CFirstName = new JLabel("First Name"); Cfname = new JTextField(10); jbsubmit = new JButton("PREVIEW"); CFirstName.setBounds(10, 20, 100, 35); Cfname.setBounds(150, 20, 150, 25); jbsubmit.setBounds(190, 110, 92, 25); cp.add(CFirstName); cp.add(Cfname); cp.add(jbsubmit); jbsubmit.addActionListener(this); rframe.add(cp); rframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); rframe.setVisible(true); } public void actionPerformed(ActionEvent ae) { String action = ae.getActionCommand(); if (action == "PREVIEW") { /* Write the code here * When we click on preview button the frame of outer class(class A) gets * deactivated(closed) and inner frame, frame of inner class(class B) gets visible. * it should not be overlapped. */ /* My Code */ new B(); rframe.setVisible(false); } } public class B { JFrame frm = new JFrame(); Container cp; public B() { frm.setSize(500, 200); frm.setLocationRelativeTo(null); cp = getContentPane(); cp.setLayout(null); setSize(550, 300); frm.setTitle("Inner Frame"); cp.setBackground(new Color(140, 180, 180)); JLabel cpn = new JLabel("hello"); cpn.setBounds(10, 20, 100, 35); cp.add(cpn); frm.add(cp); frm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frm.setVisible(true); } } public static void main(String[] args) { new A(); } }

    Read the article

  • Beginning Java (Working with Arrays; Class Assignment)

    - by Jason
    I am to the point where I feel as if I correctly wrote the code for this homework assignment. We were given a skeleton and 2 classes that we had to import (FileIOHelper and Student). /* * Created: *** put the date here *** * * Author: *** put your name here *** * * The program will read information about students and their * scores from a file, and output the name of each student with * all his/her scores and the total score, plus the average score * of the class, and the name and total score of the students with * the highest and lowest total score. */ // import java.util.Scanner; import java.io.*; // C:\Users\Adam\info.txt public class Lab6 { public static void main(String[] args) throws IOException { // Fill in the body according to the following comments Scanner key boardFile = new Scanner(System.in); // Input file name String filename = getFileName(keyboardFile); //Open the file // Input number of students int numStudents = FileIOHelper.getNumberOfStudents(filename); Student students[] = new Student[numStudents]; // Input all student records and create Student array and // integer array for total scores int totalScore[] = new int[students.length]; for (int i = 0; i < students.length; i++){ for(int j = 1; j < 4; j++){ totalScore[i] = totalScore[i] + students[i].getScore(j); } } // Compute total scores and find students with lowest and // highest total score int maxScore = 0; int minScore = 0; for(int i = 0; i < students.length; i++){ if(totalScore[i] >= totalScore[maxScore]){ maxScore = i; } else if(totalScore[i] <= totalScore[minScore]){ minScore = i; } } // Compute average total score int allScores = 0; int average = 0; for (int i = 0; i < totalScore.length; i++){ allScores = allScores + totalScore[i]; } average = allScores / totalScore.length; // Output results outputResults(students, totalScore, maxScore, minScore, average); } // Given a Scanner in, this method prompts the user to enter // a file name, inputs it, and returns it. private static String getFileName(Scanner in) { // Fill in the body System.out.print("Enter the name of a file: "); String filename = in.next(); return filename; // Do not declare the Scanner variable in this method. // You must use the value this method receives in the // argument (in). } // Given the number of students records n to input, this // method creates an array of Student of the appropriate size, // reads n student records using the FileIOHelper, and stores // them in the array, and finally returns the Student array. private static Student[] getStudents(int n) { Student[] myStudents = new Student[n]; for(int i = 0; i <= n; i++){ myStudents[i] = FileIOHelper.getNextStudent(); } return myStudents; } // Given an array of Student records, an array with the total scores, // the indices in the arrays of the students with the highest and // lowest total scores, and the average total score for the class, // this method outputs a table of all the students appropriately // formatted, plus the total number of students, the average score // of the class, and the name and total score of the students with // the highest and lowest total score. private static void outputResults( Student[] students, int[] totalScores, int maxIndex, int minIndex, int average ) { // Fill in the body System.out.println("\nName \t\tScore1 \tScore2 \tScore3 \tTotal"); System.out.println("--------------------------------------------------------"); for(int i = 0; i < students.length; i++){ outputStudent(students[i], totalScores[i], average); System.out.println(); } System.out.println("--------------------------------------------------------"); outputNumberOfStudents(students.length); outputAverage(average); outputMaxStudent(students[maxIndex], totalScores[maxIndex]); outputMinStudent(students[minIndex], totalScores[minIndex]); System.out.println("--------------------------------------------------------"); } // Given a Student record, the total score for the student, // and the average total score for all the students, this method // outputs one line in the result table appropriately formatted. private static void outputStudent(Student s, int total, int avg) { System.out.print(s.getName() + "\t"); for(int i = 1; i < 4; i++){ System.out.print(s.getScore(i) + "\t"); } System.out.print(total + "\t"); if(total < avg){ System.out.print("-"); }else if(total > avg){ System.out.print("+"); }else{ System.out.print("="); } } // Given the number of students, this method outputs a message // stating what the total number of students in the class is. private static void outputNumberOfStudents(int n) { System.out.println("The total number of students in this class is: \t" + n); } // Given the average total score of all students, this method // outputs a message stating what the average total score of // the class is. private static void outputAverage(int average) { System.out.println("The average total score of the class is: \t" + average); } // Given the Student with highest total score and the student's // total score, this method outputs a message stating the name // of the student and the highest score. private static void outputMaxStudent( Student student, int score ) { System.out.println(student.getName() + " got the maximum total score of: \t" + score); } // Given the Student with lowest total score and the student's // total score, this method outputs a message stating the name // of the student and the lowest score. private static void outputMinStudent( Student student, int score ) { System.out.println(student.getName() + " got the minimum total score of: \t" + score); } } But now I get an error at the line totalScore[i] = totalScore[i] + students[i].getScore(j); Exception in thread "main" java.lang.NullPointerException at Lab6.main(Lab6.java:42)

    Read the article

  • Interfaces on an abstract class

    - by insta
    My coworker and I have different opinions on the relationship between base classes and interfaces. I'm of the belief that a class should not implement an interface unless that class can be used when an implementation of the interface is required. In other words, I like to see code like this: interface IFooWorker { void Work(); } abstract class BaseWorker { ... base class behaviors ... public abstract void Work() { } protected string CleanData(string data) { ... } } class DbWorker : BaseWorker, IFooWorker { public void Work() { Repository.AddCleanData(base.CleanData(UI.GetDirtyData())); } } The DbWorker is what gets the IFooWorker interface, because it is an instantiatable implementation of the interface. It completely fulfills the contract. My coworker prefers the nearly identical: interface IFooWorker { void Work(); } abstract class BaseWorker : IFooWorker { ... base class behaviors ... public abstract void Work() { } protected string CleanData(string data) { ... } } class DbWorker : BaseWorker { public void Work() { Repository.AddCleanData(base.CleanData(UI.GetDirtyData())); } } Where the base class gets the interface, and by virtue of this all inheritors of the base class are of that interface as well. This bugs me but I can't come up with concrete reasons why, outside of "the base class cannot stand on its own as an implementation of the interface". What are the pros & cons of his method vs. mine, and why should one be used over another?

    Read the article

  • Generic Singleton Façade design pattern

    - by Paul
    Hi I try write singleton façade 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(); } } } I use this for my problem. public class SingletonFasade<T1, T2, T3> where T1 : class, IMyInterface, new() where T2 : class, IMyInterface, new() where T3 : class, IMyInterface, new() {//...} Is any solution without Interfaces ??

    Read the article

  • Java multiple class compositing and boiler plate reduction

    - by h2g2java
    We all know why Java does/should not have multiple inheritance. So this is not questioning about what has already been debated till-cows-come-home. This discusses what we would do when we wish to create a class that has the characteristics of two or more other classes. Probably, most of us would do this to "inherit" from three classes. For simplicity, I left out the constructor.: class Car extends Vehicle { final public Transport transport; final public Machine machine; } So that, Car class directly inherits methods and objects of Vehicle class, but would have to refer to transport and machine explicitly to refer to objects instantiated in Transport and Machine. Car car = new Car(); car.drive(); // from Vehicle car.transport.isAmphibious(); // from Transport car.machine.getCO2Footprint(); // from Machine I thought this was a good idea until when I encounter frameworks that require setter and getter methods. For example, the XML <Car amphibious='false' footPrint='1000' model='Fordstatic999'/> would look for the methods setAmphibious(..), setFootPrint(..) and setModel(..). Therefore, I have to project the methods from Transport and Machine classes class Car extends Vehicle { final public Transport transport; final public Machine machine; public void setAmphibious(boolean b){ this.transport.setAmphibious(b); } public void setFootPrint(String fp){ this.machine.setFootPrint(fp); } } This is OK, if there were just a few characteristics. Right now, I am trying to adapt all of SmartGWT into GWT UIBinder, especially those classes that are not a GWT widget. There are lots of characteristics to project. Wouldn't it be nice if there exists some form of annotation framework that is like this: class Car extends Vehicle @projects {Transport @projects{Machine @projects Guzzler}} { /* No need to explicitly instantiate Transport, Machine or Guzzler */ .... } Where, in case of common names of characteristics exist, the characteristics of Machine would take precedence Guzzler's, and Transport's would have precedence over Machine's, and Vehicle's would have precedence over Transport's. The annotation framework would then instantiate Transport, Machine and Guzzler as hidden members of Car and expand to break-out the protected/public characteristics, in the precedence dictated by the @project annotation sequence, into actual source code or into byte-code. Preferably into byte-code. So that the setFootPrint method is found in both Machine and Guzzler, only that of Machine's would be projected. Questions: Don't you think this is a good idea to have such a framework? Does such a framework already exist? Tell me where/what. Is there an eclipse plugin that does it? Is there a proposal or plan anywhere that you know about such an annotation framework? It would be wonderful too, if the annotation/plugin framework lets me specify that boolean, int, or whatever else needs to be converted from String and does the conversion/parsing for me too. Please advise, somebody. I hope wording of my question was clear enough. Thx. Edited: To avoid OO enthusiasts jumping to conclusion, I have renamed the title of this question.

    Read the article

  • Java: how do I get a class literal from a generic type?

    - by Tom
    Typically, I've seen people use the class literal like this: Class<Foo> cls = Foo.class; But what if the type is generic, e.g. List? This works fine, but has a warning since List should be parameterized: Class<List> cls = List.class So why not add a <?>? Well, this causes a type mismatch error: Class<List<?>> cls = List.class I figured something like this would work, but this is just a plain ol' a syntax error: Class<List<Foo>> cls = List<Foo>.class How can I get a Class<List<Foo>> statically, e.g. using the class literal? I could use @SuppressWarnings("unchecked") to get rid of the warnings caused by the non-parameterized use of List in the first example, Class<List> cls = List.class, but I'd rather not. Any suggestions? Thanks!

    Read the article

  • How to refactor a Python “god class”?

    - by Zearin
    Problem I’m working on a Python project whose main class is a bit “God Object”. There are so friggin’ many attributes and methods! I want to refactor the class. So Far… For the first step, I want to do something relatively simple; but when I tried the most straightforward approach, it broke some tests and existing examples. Basically, the class has a loooong list of attributes—but I can clearly look over them and think, “These 5 attributes are related…These 8 are also related…and then there’s the rest.” getattr I basically just wanted to group the related attributes into a dict-like helper class. I had a feeling __getattr__ would be ideal for the job. So I moved the attributes to a separate class, and, sure enough, __getattr__ worked its magic perfectly well… At first. But then I tried running one of the examples. The example subclass tries to set one of these attributes directly (at the class level). But since the attribute was no longer “physically located” in the parent class, I got an error saying that the attribute did not exist. @property I then read up about the @property decorator. But then I also read that it creates problems for subclasses that want to do self.x = blah when x is a property of the parent class. Desired Have all client code continue to work using self.whatever, even if the parent’s whatever property is not “physically located” in the class (or instance) itself. Group related attributes into dict-like containers. Reduce the extreme noisiness of the code in the main class. For example, I don’t simply want to change this: larry = 2 curly = 'abcd' moe = self.doh() Into this: larry = something_else('larry') curly = something_else('curly') moe = yet_another_thing.moe() …because that’s still noisy. Although that successfully makes a simply attribute into something that can manage the data, the original had 3 variables and the tweaked version still has 3 variables. However, I would be fine with something like this: stooges = Stooges() And if a lookup for self.larry fails, something would check stooges and see if larry is there. (But it must also work if a subclass tries to do larry = 'blah' at the class level.) Summary Want to replace related groups of attributes in a parent class with a single attribute that stores all the data elsewhere Want to work with existing client code that uses (e.g.) larry = 'blah' at the class level Want to continue to allow subclasses to extend, override, and modify these refactored attributes without knowing anything has changed Is this possible? Or am I barking up the wrong tree?

    Read the article

  • How to use a separate class to validate credit card numbers in C#

    - by EvanRyan
    I have set up a class to validate credit card numbers. The credit card type and number are selected on a form in a separate class. I'm trying to figure out how to get the credit card type and number that are selected in the other class (frmPayment) in to my credit card class algorithm: public enum CardType { MasterCard, Visa, AmericanExpress } public sealed class CardValidator { public static string SelectedCardType { get; private set; } public static string CardNumber { get; private set; } private CardValidator(string selectedCardType, string cardNumber) { SelectedCardType = selectedCardType; CardNumber = cardNumber; } public static bool Validate(CardType cardType, string cardNumber) { byte[] number = new byte[16]; int length = 0; for (int i = 0; i < cardNumber.Length; i++) { if (char.IsDigit(cardNumber, i)) { if (length == 16) return false; number[length++] = byte.Parse(cardNumber[i]); //not working. find different way to parse } } switch(cardType) { case CardType.MasterCard: if(length != 16) return false; if(number[0] != 5 || number[1] == 0 || number[1] > 5) return false; break; case CardType.Visa: if(length != 16 & length != 13) return false; if(number[0] != 4) return false; break; case CardType.AmericanExpress: if(length != 15) return false; if(number[0] != 3 || (number[1] != 4 & number[1] != 7)) return false; break; } // Use Luhn Algorithm to validate int sum = 0; for(int i = length - 1; i >= 0; i--) { if(i % 2 == length % 2) { int n = number[i] * 2; sum += (n / 10) + (n % 10); } else sum += number[i]; } return (sum % 10 == 0); } }

    Read the article

  • impress.js Navigation with active class

    - by ArtGoddess
    I would like to use impress.js in order to make a website, with a navigation bar. In each slide, the corresponding anchor or div must have an "active" class, in order to achieve a different link appearance. I have followed all instructions provided here: https://github.com/Ralt/impress.js/commit/f88feb8cae704ce27bd2168bdb77768f516ac2da#L2R605 but the "active" class on the correct menu must be added. This is the code that generates the menu items. How can I add for example the "active" class in the first link? /* ************************ MENU ***************************** */ // Capitalize first letter of string // @see http://stackoverflow.com/a/1026087/851498 var capitalize = function( str ) { return str.charAt(0).toUpperCase() + str.slice(1); } // `showMenu` API function creates the menu // It defines the names of each entry by the id capitalized. var showMenu = function() { // Create the menu wrapper and the element that will be cloned // for each entry. var menu = document.createElement('div'), el = document.createElement('div'); // Apply some classes menu.className = 'menu'; el.className = 'menu-item'; // Create an element that will be the "button" and append it // to the menu var button = document.createElement('div'); button.className = 'menu-button'; button.textContent = 'Menu'; menu.appendChild(button); // Now, for each div in #impress, add an entry to the menu [].forEach.call(byId('impress').firstElementChild.children, function( child, index ) { var newEl = el.cloneNode(), i = index + 1, text = i + '. ' + capitalize(child.id); // Set the text of the new element newEl.textContent = text; // Add an onclick event to the new element // We need to use a closure to make sure the index is correct (function( index ) { newEl.addEventListener('click', function() { goto(index); }); }( index )); // And append the new element to the menu menu.appendChild(newEl); }); // And append the menu to #impress document.body.appendChild(menu); }; Then, in each click it must be removed the active class on the current, and add it to the clicked element. // Remove the active class from the current active document.querySelector( '.active' )[ 0 ].classList.remove( 'active' ); // And add it to the clicked index byId('impress').firstElementChild.children[ index ].classList.add( 'active' ); Where do I have to apply this code? Thank you!

    Read the article

  • C# - Get values of static properties from static class

    - by JamesW
    I'm trying to loop through some static properties in a simple static class in order to populate a combo box with their values, but am having difficulties. Here is the simple class: public static MyStaticClass() { public static string property1 = "NumberOne"; public static string property2 = "NumberTwo"; public static string property3 = "NumberThree"; } ... and the code attempting to retrieve the values: Type myType = typeof(MyStaticClass); PropertyInfo[] properties = myType.GetProperties( BindingFlags.Public | BindingFlags.Static | BindingFlags.DeclaredOnly); foreach (PropertyInfo property in properties) { MyComboBox.Items.Add(property.GetValue(myType, null).ToString()); } If I don't supply any binding flags then I get about 57 properties including things like System.Reflection.Module Module and all sorts of other inherited things I don't care about. My 3 declared properties are not present. If I supply various combinations of other flags then it always returns 0 properties. Great. Does it matter that my static class is actually declared within another non-static class? Please help! What am I doing wrong?

    Read the article

  • g++ C++0x enum class Compiler Warnings

    - by Travis G
    I've been refactoring my horrible mess of C++ type-safe psuedo-enums to the new C++0x type-safe enums because they're way more readable. Anyway, I use them in exported classes, so I explicitly mark them to be exported: enum class __attribute__((visibility("default"))) MyEnum : unsigned int { One = 1, Two = 2 }; Compiling this with g++ yields the following warning: type attributes ignored after type is already defined This seems very strange, since, as far as I know, that warning is meant to prevent actual mistakes like: class __attribute__((visibility("default"))) MyClass { }; class __attribute__((visibility("hidden"))) MyClass; Of course, I'm clearly not doing that, since I have only marked the visibility attributes at the definition of the enum class and I'm not re-defining or declaring it anywhere else (I can duplicate this error with a single file). Ultimately, I can't make this bit of code actually cause a problem, save for the fact that, if I change a value and re-compile the consumer without re-compiling the shared library, the consumer passes the new values and the shared library has no idea what to do with them (although I wouldn't expect that to work in the first place). Am I being way too pedantic? Can this be safely ignored? I suspect so, but at the same time, having this error prevents me from compiling with Werror, which makes me uncomfortable. I would really like to see this problem go away.

    Read the article

  • class array variable initialization error in java

    - by trinity
    Hello I am trying to write a java program that reads an input file consisting of URLs , extracts tokens from these , and accordingly insert into : class Tokens { String name ; int count ; } , where name is the name of every unique token , and count is the frequency of that token in the URLs file..I've written the following code : import java.io.*; import java.net.*; public class Main { static class Tokens { String name; int count; } public static void main(String[] args) { String url_str,host; String htokens[]; URL url; boolean found=false; Tokens t[]; int i,j,k; try { File f=new File("urlfile.txt"); FileReader fr=new FileReader(f); BufferedReader br=new BufferedReader(fr); while((url_str=br.readLine())!=null) { url=new URL(url_str); host=url.getHost(); htokens=host.split("\\.|\\-|\\_|\\~|[0-9]"); for(i=0;i<htokens.length;i++) { if(!htokens[i].isEmpty()) { for(j=0;j<t.length;j++) { if(htokens[i].equals(t[j].name)) { t[j].count++; found=true; } } if(!found) { k=t.length; t[k].name=htokens[i]; t[k].count=1; } } } System.out.println(t.length + "class tokens :"); for(i=0;i<t.length;i++) { System.out.println("name :"+t[i].name+" frequency :"+t[i].count); } } br.close(); fr.close(); } catch(Exception e) { System.out.println(e); } } } But when i run it , it says : variable t not initialized.. What should i do to set it right ?

    Read the article

  • Extension methods in class library project

    - by Mostafa
    I've implemented some extension methods and put those in separate Class Library project. Imagine I have a simple extension method like this in class library called MD.Utility: namespace MD.Utility { public static class ExtenMethods { public static bool IsValidEmailAddress(this string s) { Regex regex = new Regex(@"^[\w-\.]+@([\w-]+\.)+[\w-]{2,4}$"); return regex.IsMatch(s); } } } But nowhere in WebApp like App_code folder or WebFroms code-behind page I can't use this Extension method. If I do like this: using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using MD.Utility; public partial class _Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { string email = "[email protected]"; if (email.IsValidEmailAddress()) { //To do } } } The compiler doesn't recognize IsValidEmailAddress() and even no intellisense support. While if I put my extension method in App_Code folder it's ok for using in another cs file in App_code Folder or Web Form code-behind pages.

    Read the article

  • flash as3 document class and event listeners

    - by Lee
    I think i have this document class concept entirly wrong now, i was wondering if someone mind explaining it.. I assumed that the above class would be instantiated within the first frame on scene one of a movie. I also assumed that when changing scenes the state of the class would remain constant so any event listeners would still be running.. Scene 1: I have a movieclip named ui_mc, that has a button in for muting sound. Scene 2: I have the same movie clip with the same button. Now the eventListener picks it up in the first scene, however it does not in the second. I am wondering for every scene do the event listeners need to be resetup? If that is the case if their an event listener to listen for the change in scene, so i can set them back up again lol.. Thanks in advance.. package { import flash.display.MovieClip; import flash.events.MouseEvent; import flash.media.Sound; import flash.media.SoundChannel; public class game extends MovieClip { public var snd_state:Boolean = true; public function game() { ui_setup(); } public function ui_setup():void { ui_mc.toggleMute_mc.addEventListener(MouseEvent.CLICK, snd_toggle); } private function snd_toggle(event:MouseEvent):void { // 0 = No Sound, 1 = Full Sound trace("Toggle"); } } }

    Read the article

< Previous Page | 20 21 22 23 24 25 26 27 28 29 30 31  | Next Page >