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  • Javascript hide/show classes with checkbox

    - by Christina
    I am just learning javascript, so please bear with me! I want to be able to use checkboxes to choose to hide/show div classes (to basically filter the amount of info being shown). It is done in this... but I'm try to figure out something much simpler (since I don't need to dynamically generate the checkbox options.) I came across this example: The Javascript: function showMe (it, box) { var vis = (box.checked) ? "block" : "none"; document.getElementById(it).style.display = vis; } The HTML <form> <input type="checkbox" checked="checked" value="value1" onclick="showMe('div1', this)" />value1 <input type="checkbox" checked="checked" value="value2" onclick="showMe('div2', this)" />value2 <input type="checkbox" checked="checked" value="value3" onclick="showMe('div3', this)" />value3 </form> <div id="div1" style="display:block">Show Div 1</div> <div id="div2" style="display:block">Show Div 2</div> <div id="div3" style="display:block">Show Div 3</div> </body> </html> But it only works for div ids, not classes. Any idea on how I can work this? Thanks in advance if you can help me out!

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  • Storing an object to use in multiple classes

    - by Aaron Sanders
    I am wondering the best way to store an object in memory that is used in a lot of classes throughout an application. Let me set up my problem for you: We have multiple databases, 1 per customer. We also have a master table and each row is detailed information about the databases such as database name, server IP it's located and a few config settings. I have an application that loops through those multiple databases and runs some updates on them. The settings I mentioned above are updated each loop iteration into memory. The application then runs through series of processes that include multiple classes using this data. The data never changes during the processes, only during the loop iteration. The variables are related to a customer, so I have them stored in a customer class. I suppose I could make all of the members shared or should I use a singleton for the customer class? I've never actually used a singleton, only read they are good in this type of situation. Are there better solutions to this type of scenario? Also, I could have plans for this application to be multithreaded later. Sorry if this is confusing. If you have questions, let me know and I will answer them. Thanks for your help.

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  • jQuery element with multiple classes: storing one class as a var

    - by Aaron
    I'm trying to create a standardized show/hide element system, like so: <div class="opener popup_1">Click Me</div> <div class="popup popup_1">I'm usually hidden</div> Clicking on the div with the opener class should show() the div with the popup class. I don't know how many opener/popup combinations I'm going to have on any given page, I don't know where on any given page the opener and the popup are going to be displayed, and I don't know how many popups a given opener should call show() for. Both the opener and the popup have to be able to have more classes than just what's used by jQuery. What I'd like to do is something like this: $(".opener").click(function() { var openerTarget = $(this).attr("class").filter(function() { return this.class.match(/^popup_([a-zA-Z0-9-_\+]*) ?$/); }); $(".popup." + openerTarget).show(); The idea is that when you click on an opener, it filters out "popup_whatever" from opener's classes and stores that as openerTarget. Then anything with class=popup and openerTarget will be shown.

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  • Object Oriented Programming in AS3

    - by Jordan
    I'm building a game in as3 that has balls moving and bouncing off the walls. When the user clicks an explosion appears and any ball that hits that explosion explodes too. Any ball that then hits that explosion explodes and so on. My question is what would be the best class structure for the balls. I have a level system to control levels and such and I've already come up with working ways to code the balls. Here's what I've done. My first attempt was to create a class for Movement, Bounce, Explosion and finally Orb. These all extended each other in the order I just named them. I got it working but having Bounce extend Movement and Explosion extend Bounce, it just doesn't seem very object oriented because what if I wanted to add a box class that didn't move, but did explode? I would need a separate class for that explosion. My second attempt was to create Movement, Bounce and Explosion without extending anything. Instead I passed in a reference to the Orb class to each. Then the class stores that reference and does what it needs to do based on events that are dispatched by the Orb such as update, which was broadcast from Orb every enter frame. This would drive the movement and bounce and also the explosion when the time came. This attempt worked as well but it just doesn't seem right. I've also thought about using Interfaces but because they are more of an outline for classes, I feel like code reuse goes out the window as each class would need its own code for a specific task even if that task is exactly the same. I feel as if I'm searching for some form of multiple inheritance for classes that as3 does not support. Can someone explain to me a better way of doing what I'm attempting to do? Am I being to "Object Oriented" by having classed for Movement, Bounce, Explosion and Orb? Are Interfaces the way to go? Any feedback is appreciated!

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  • why is OOP hard for me?

    - by netrox
    I have trouble writing OOP in PHP... I understand the concept but I never create classes for my projects... mainly because it's often a small project and nothing complex. But when I read OOP, it seems more difficult to code than writing simple procedural statements. It also seems to take a lot of room as well with so many empty abstract classes and that can be easily lost in the land of objects... it's becoming like a junkyard to me. Also, I noticed that virtually all instructions on how to use OOP use "car" or "cat" or "dog" analogies. Hello... we're not dealing with animals or cars... we're dealing with windows or consoles. You can talk about analogies to death and I will never learn. What I want is see a code that's written to show how objects are created - not, "aCow-moo!" For example, I want to see a browser window object displaying say... three inputs. I want to see an "object" created to output a window with three inputs then I want to see how overriding works, like change the window object to display only two inputs instead of three inputs. I think that would make learning more easy, wouldn't it? Any recommended tutorials of that nature instead of quacks, moos, and woofs.

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  • Unit test project doesn't recognize the classes it was generated from

    - by DougLeary
    I have a fairly simple file-system website consisting of one aspx page and several classes in separate .cs files. Everything is on my own HD. The web app itself builds and runs fine. Out of curiosity I decided to try out Visual Studio's nifty, easy-to-use unit test feature. So I opened each class file and clicked Create Unit Tests. VS generated a test project containing a set of test classes and some other files. Easy! But when I try to build or run the test project it throws a series of build errors, one for every class: The type or namespace name 'class-name' could not be found (are you missing a using directive or an assembly reference?). Somebody asked if my test project has a reference to the original project. Well no, because the original project is a file-system website. It has no bin folder and no DLL, so there's nothing to reference as far as I can tell. I would think that since VS generated these unit tests it would generate whatever references it needs, but apparently not. Is generating unit tests for file-system web apps an undocumented no-no, or is there a magic trick to getting it to work?

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  • c# multi inheritance

    - by user326839
    So ive got a base class which requires a Socket: class Sock { public Socket s; public Sock(Socket s) { this.s = s; } public virtual void Process(byte[] data) { } ... } then ive got another class. if a new socket gets accepted a new instance of this class will be created: class Game : Sock { public Random Random = new Random(); public Timerr Timers; public Test Test; public Game(Socket s) : base(s) { } public static void ReceiveNewSocket(object s) { Game Client = new Game((Socket)s); Client.Start(); } public override void Process(byte[] buf) { Timers = new Timerr(s); Test = new Test(s); Test.T(); } } in the Sock class ive got a virtual function that gets overwritten by the Game class.(Process function) in this function im calling a function from the Test Class(Test+ Timerr Class: class Test : Game { public Test(Socket s) : base(s) { } public void T() { Console.WriteLine(Random.Next(0, 10)); Timers.Start(); } } class Timerr : Game { public Timerr(Socket s) : base(s) { } public void Start() { Console.WriteLine("test"); } } ) So in the Process function im calling a function in Test. And in this function(T) i need to call a function from the Timerr Class.But the problem is its always NULL , although the constructor is called in Process. And e.g. the Random Class can be called, i guess its because its defined with the constructor.: public Random Random = new Random(); and thats why the other classes(without a constructor): public Timerr Timers; public Test Test; are always null in the inherited class Test.But its essentiel that i call other Methods of other classes in this function.How could i solve that?

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  • Toggle two divs and classes

    - by kuswantin
    I have two links with classes (login-form and register-form) relevant to their target forms ID, they want to toggle. I have also a predefined 'slideToggle' function to toggle better. This is what I have tried so far: $('#userbar a').click(function() { var c = $(this).attr('class'); $('#userbar a').removeClass('active'); $(this).toggleClass('active'); $('#register-form,#login-form').hide(); //bad, causing flashy $('#' + c).slideToggle('slow'); return false; }); With this I have trouble with the flashy window, and to correctly toggle the active classes when another link is clicked, the other link should not have active class anymore. Additional problem is the link is dead on serial clicks. I have another try, longer one: $('#userbar a').click(function() { var c = $(this).attr('class'); switch (c) { case 'login-form': $('#' + c).slideToggle('slow'); $(this).toggleClass('active'); $('#register-form').hide(); break; case 'register-form': $('#' + c).slideToggle('slow'); $(this).toggleClass('active'); $('#login-form').hide(); break; } return false; }); This one is worse than the first :( Any suggestion to correct the behavior? What I want is when a link with class login-form is click, so toggle the form with ID login-form, and hide the register-form if open. Any help would be very much appreciated. Thanks.

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  • DRYing out implementation of ICloneable in several classes

    - by Sarah Vessels
    I have several different classes that I want to be cloneable: GenericRow, GenericRows, ParticularRow, and ParticularRows. There is the following class hierarchy: GenericRow is the parent of ParticularRow, and GenericRows is the parent of ParticularRows. Each class implements ICloneable because I want to be able to create deep copies of instances of each. I find myself writing the exact same code for Clone() in each class: object ICloneable.Clone() { object clone; using (var stream = new MemoryStream()) { var formatter = new BinaryFormatter(); // Serialize this object formatter.Serialize(stream, this); stream.Position = 0; // Deserialize to another object clone = formatter.Deserialize(stream); } return clone; } I then provide a convenience wrapper method, for example in GenericRows: public GenericRows Clone() { return (GenericRows)((ICloneable)this).Clone(); } I am fine with the convenience wrapper methods looking about the same in each class because it's very little code and it does differ from class to class by return type, cast, etc. However, ICloneable.Clone() is identical in all four classes. Can I abstract this somehow so it is only defined in one place? My concern was that if I made some utility class/object extension method, it would not correctly make a deep copy of the particular instance I want copied. Is this a good idea anyway?

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  • Multiple Inheritence with same Base Classes in Python

    - by Jordan Reiter
    I'm trying to wrap my head around multiple inheritance in python. Suppose I have the following base class: class Structure(object): def build(self, *args): print "I am building a structure!" self.components = args And let's say I have two classes that inherit from it: class House(Structure): def build(self, *args): print "I am building a house!" super(House, self).build(*args) class School(Structure): def build(self, type="Elementary", *args): print "I am building a school!" super(School, self).build(*args) Finally, a create a class that uses multiple inheritance: class SchoolHouse(School, House): def build(self, *args): print "I am building a schoolhouse!" super(School, self).build(*args) Then, I create a SchoolHouse object and run build on it: >>> sh = SchoolHouse() >>> sh.build("roof", "walls") I am building a schoolhouse! I am building a house! I am building a structure! So I'm wondering -- what happened to the School class? Is there any way to get Python to run both somehow? I'm wondering specifically because there are a fair number of Django packages out there that provide custom Managers for models. But there doesn't appear to be a way to combine them without writing one or the other of the Managers as inheriting from the other one. It'd be nice to just import both and use both somehow, but looks like it can't be done? Also I guess it'd just help to be pointed to a good primer on multiple inheritance in Python. I have done some work with Mixins before and really enjoy using them. I guess I just wonder if there is any elegant way to combine functionality from two different classes when they inherit from the same base class.

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  • Using JMX classes to notify on events over time

    - by Cincinnati Joe
    I've been looking at JMX for monitoring application and system metrics (partially because MBeans can accessed by various tools such as JConsole). It would seem like the classes included with JMX would be useful for things like notification when metrics have exceeded thresholds. But I'm not sure they fit with the way I want to measure these over a specified time period. For example, let's say I want to notify an admin when the average CPU load is over 95% for more than 5 minutes. Is that something can be done with a GaugeMonitor? From the docs, it doesn't seem quite suited for this, and I'm wondering if instead I should write my own MBean with the necessary logic. A more relevant example is when the login times for users exceed 10s over a period of 5 mins. Slightly different would be the last 20 logins took more than 10s on average. Another case would be when a process crashes 4+ times in an hour. Or the request queue exceeds 15 for 5 mins. Are the JMX Monitor classes useful for this kind of thing?

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  • Duplicate C# web service proxy classes generated for Java types

    - by Sergey
    My question is about integration between a Java web service and a C# .NET client. Service: CXF 2.2.3 with Aegis databinding Client: C#, .NET 3.5 SP1 For some reason Visual Studio generates two C# proxy enums for each Java enum. The generated C# classes do not compile. For example, this Java enum: public enum SqlDialect { GENERIC, SYBASE, SQL_SERVER, ORACLE; } Produces this WSDL: <xsd:simpleType name="SqlDialect"> <xsd:restriction base="xsd:string"> <xsd:enumeration value="GENERIC" /> <xsd:enumeration value="SYBASE" /> <xsd:enumeration value="SQL_SERVER" /> <xsd:enumeration value="ORACLE" /> </xsd:restriction> </xsd:simpleType> For this WSDL Visual Studio generates two partial C# classes (generated comments removed): [System.CodeDom.Compiler.GeneratedCodeAttribute("System.Runtime.Serialization", "3.0.0.0")] [System.Runtime.Serialization.DataContractAttribute(Name="SqlDialect", Namespace="http://somenamespace")] public enum SqlDialect : int { [System.Runtime.Serialization.EnumMemberAttribute()] GENERIC = 0, [System.Runtime.Serialization.EnumMemberAttribute()] SYBASE = 1, [System.Runtime.Serialization.EnumMemberAttribute()] SQL_SERVER = 2, [System.Runtime.Serialization.EnumMemberAttribute()] ORACLE = 3, } [System.CodeDom.Compiler.GeneratedCodeAttribute("System.Xml", "2.0.50727.3082")] [System.SerializableAttribute()] [System.Xml.Serialization.XmlTypeAttribute(Namespace="http://somenamespace")] public enum SqlDialect { GENERIC, SYBASE, SQL_SERVER, ORACLE, } The resulting C# code does not compile: The namespace 'somenamespace' already contains a definition for 'SqlDialect' I will appreciate any ideas...

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  • Glassfish: Storing Java classes in the docroot folder?

    - by Tom Marthenal
    I'm very new to using Glassfish or JSP. I have this working in NetBeans (which has Glassfish bundled) but when I try to put it on my server which is running Glassfish Server, I really don't know what I'm doing. I can place a JSP file in "domains/domain1/docroot/index.jsp" and it will work when I visit my site, but I can't, for some reason, get Java classes to work. I copied the files in "/build/web/" from the NetBeans project to the docroot folder on my server. The errors I get when I visit the site are: org.apache.jasper.JasperException: PWC6033: Error in Javac compilation for JSP PWC6199: Generated servlet error: string:///index_jsp.java:7: package test does not exist PWC6197: An error occurred at line: 5 in the jsp file: /index.jsp PWC6199: Generated servlet error: string:///index_jsp.java:52: cannot find symbol symbol : class TestClass location: class org.apache.jsp.index_jsp PWC6197: An error occurred at line: 5 in the jsp file: /index.jsp PWC6199: Generated servlet error: string:///index_jsp.java:52: cannot find symbol symbol : class TestClass location: class org.apache.jsp.index_jsp The actual Java class is in "WEB-INF/classes/test/TestClass.class" (it is pre-compiled). I really have no idea what I'm doing wrong so any help is greatly appreciated. Thanks!

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  • dynamic inheritance without touching classes

    - by Jasper
    I feel like the answer to this question is really simple, but I really am having trouble finding it. So here goes: Suppose you have the following classes: class Base; class Child : public Base; class Displayer { public: Displayer(Base* element); Displayer(Child* element); } Additionally, I have a Base* object which might point to either an instance of the class Base or an instance of the class Child. Now I want to create a Displayer based on the element pointed to by object, however, I want to pick the right version of the constructor. As I currently have it, this would accomplish just that (I am being a bit fuzzy with my C++ here, but I think this the clearest way) object->createDisplayer(); virtual void Base::createDisplayer() { new Displayer(this); } virtual void Child::createDisplayer() { new Displayer(this); } This works, however, there is a problem with this: Base and Child are part of the application system, while Displayer is part of the GUI system. I want to build the GUI system independently of the Application system, so that it is easy to replace the GUI. This means that Base and Child should not know about Displayer. However, I do not know how I can achieve this without letting the Application classes know about the GUI. Am I missing something very obvious or am I trying something that is not possible?

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  • Unit test approach for generic classes/methods

    - by Greg
    Hi, What's the recommended way to cover off unit testing of generic classes/methods? For example (referring to my example code below). Would it be a case of have 2 or 3 times the tests to cover testing the methods with a few different types of TKey, TNode classes? Or is just one class enough? public class TopologyBase<TKey, TNode, TRelationship> where TNode : NodeBase<TKey>, new() where TRelationship : RelationshipBase<TKey>, new() { // Properties public Dictionary<TKey, NodeBase<TKey>> Nodes { get; private set; } public List<RelationshipBase<TKey>> Relationships { get; private set; } // Constructors protected TopologyBase() { Nodes = new Dictionary<TKey, NodeBase<TKey>>(); Relationships = new List<RelationshipBase<TKey>>(); } // Methods public TNode CreateNode(TKey key) { var node = new TNode {Key = key}; Nodes.Add(node.Key, node); return node; } public void CreateRelationship(NodeBase<TKey> parent, NodeBase<TKey> child) { . . .

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  • C# and Objects/Classes

    - by user1192890
    I have tried to compile code from Deitel's C# 2010 for programmers. I copied it exactly out of the book, but it still can't find main, even though I declared it in one of the classes. Here is a look at the two classes: For GradeBookTest: // Fig. 4.2: GradeBookTest.cs // Create a GradeBook object and call its DisplayMessage method. public class GradeBookTest { // Main method begins program execution public static void Main(string[] args) { // create a GradeBook object and assign it to myGradeBook GradeBook myGradeBook = new GradeBook(); // call myGradeBook's DisplayMessage method myGradeBook.DisplayMessage(); } // end Main } // end class GradeBookTest Now for the GradeBook class: // Fig. 4.1: GradeBook.cs // Class declaration with one method. using System; public class GradeBook { // display a welcome message to the GradeBook user public void DisplayMessage() { Console.WriteLine( "Welcome to the Grade Book!" ); } // end method DisplayMessage } // end class GradeBook That is how I copied them. Here is how they appeared in the book: 1 // Fig. 4.2: GradeBookTest.cs 2 // Create a GradeBook object and call its DisplayMessage method. 3 public class GradeBookTest 4 { 5 // Main method begins program execution 6 public static void Main( string[] args ) 7 { 8 // create a GradeBook object and assign it to myGradeBook 9 GradeBook myGradeBook = new GradeBook(); 10 11 // call myGradeBook's DisplayMessage method 12 myGradeBook.DisplayMessage(); 13 } // end Main 14 } // end class GradeBookTest and // Fig. 4.1: GradeBook.cs // Class declaration with one method. using System; public class GradeBook { // display a welcome message to the GradeBook user public void DisplayMessage() { Console.WriteLine( "Welcome to the Grade Book!" ); } // end method DisplayMessage } // end class GradeBook I don't see why they are not working. Right now I am using Visual Studio Pro 2010. Any Thoughts?

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  • Unobstrusive pseudo-classes and attribute selectors emulation in IE

    - by Álvaro G. Vicario
    I'm trying to emulate some pseudo-classes and attribute selectors in Internet Explorer 6 and 7, such as :focus, :hover or [type=text]. So far, I've managed to add a class name to the affected elements: $("input, textarea, select") .hover(function(){ $(this).addClass("hover"); }, function(){ $(this).removeClass("hover"); }) .focus(function(){ $(this).addClass("focus"); }) .blur(function(){ $(this).removeClass("focus"); }); $("input[type=text]").each(function(){ $(this).addClass("text"); }); However, I'm still forced to duplicate selector in my style sheets: textarea:focus, textarea.focus{ } And, to make things worse, IE6 seems to ignore all the selectors when it finds an attribute: input[type=text], input.text{ /* IE6 ignores this */ } And, of course, IE6 ignores selectors with multiple classes: input.text.focus{ /* IE6 ignores this */ } So I'm likely to end up with this mess: input[type=text]{ /* Rules here */ } input.text{ /* Same rules again */ } input[type=text]:focus{ } input.text_and_focus{ } input.text_and_hover{ } input.text_and_focus_and_hover{ } My question: is there any way to read the rules or computed style defined for a CSS selector and apply it to certain elements, so I only need to maintain one set of standard CSS?

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  • Design issue when having classes implement different interfaces to restrict client actions

    - by devoured elysium
    Let's say I'm defining a game class that implements two different views: interface IPlayerView { void play(); } interface IDealerView { void deal(); } The view that a game sees when playing the game, and a view that the dealer sees when dealing the game (this is, a player can't make dealer actions and a dealer can't make player actions). The game definition is as following: class Game : IPlayerView, IDealerView { void play() { ... } void deal() { ... } } Now assume I want to make it possible for the players to play the game, but not to deal it. My original idea was that instead of having public Game GetGame() { ... } I'd have something like public IPlayerView GetGame() { ... } But after some tests I realized that if I later try this code, it works: IDealerView dealerView = (IDealerView)GameClass.GetGame(); this works as lets the user act as the dealer. Am I worrying to much? How do you usually deal with this patterns? I could instead make two different classes, maybe a "main" class, the dealer class, that would act as factory of player classes. That way I could control exactly what I would like to pass on the the public. On the other hand, that turns everything a bit more complex than with this original design. Thanks

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  • Use of Java [Interfaces / Abstract classes]

    - by Samuel
    Hello, Lately i decided to take a look at Java so i am still pretty new to it and also to the approach of OO programming, so i wanted to get some things straight before learning more, (i guess it's never to soon to start with good practices). I am programming a little 2D game for now but i think my question applies to any non trivial project. For the simplicity i'll provide examples from my game. I have different kinds of zombies, but they all have the same attributes (x, y, health, attack etc) so i wrote an interface Zombie which i implement by WalkingZombie, RunningZombie TeleportingZombie etc. Is this the best thing to do? Am i better of with an abstract class? Or with a super class? (I am not planning to partially implement functions - therefor my choice for an interface instead of an abstract class) I have one class describing the main character (Survivor) and since it is pretty big i wanted to write an interface with the different functions, so that i can easily see and share the structure of it. Is it good practice? Or is it simply a waste of space and time? I hope this question will not be rated as subjective because i thought that experienced programmers won't disagree about this kind of topic since the use of interfaces / super classes / abstract classes follows logical rules and is thereby not simply a personal choice. Thank you for your time -Samuel

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  • AttributeError in my Python program regarding classes

    - by Axel Finkel
    I'm doing an exercise out of the Python book that involves creating a class and a subclass. I am getting the following error when I try to run the program: AttributeError: 'Customer' object has no attribute 'name', when it tries to go through this bit of code: self.name.append(name) As this is my first time dealing with classes and objects in Python, I'm sure I am making some overt mistake somewhere, but I can't seem to figure it out. I've looked over the documentation for creating classes and writing member functions, and it looks correct, but it is obviously not. I want the Customer subclass to inherit the name, address, and telephone attributes from the Person superclass, but it doesn't seem to be doing so? Here is my code: class Person: def __init__(self): self.name = None self.address = None self.telephone = None def changeName(self, name): self.name.append(name) def changeAddress(self, address): self.address.append(address) def changeTelephone(self, telephone): self.telephone.append(telephone) class Customer(Person): def __init__(self): self.customerNumber = None self.onMailingList = False def changeCustomerNumber(self, customerNumber): self.customerNumber.append(customerNumber) def changeOnMailingList(): if onMailingList == False: onMailingList == True else: onMailingList == False def main(): customer1 = Customer() name = 'Bob Smith' address = '123 Somewhere Road' telephone = '111 222 3333' customerNumber = '12345' customer1.changeName(name) customer1.changeAddress(address) customer1.changeTelephone(telephone) customer1.changeCustomerNumber(customerNumber) print("Customer name: " + customer1.name) print("Customer address: " + customer1.address) print("Customer telephone number: " + customer1.telephone) print("Customer number: " + customer1.customerNumber) print("On mailing list: " + customer1.OnMailingList) customer1.changeOnMailingList() print("On mailing list: " + customer1.OnMailingList) main()

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  • Saving associated domain classes in Grails

    - by Cesar
    I'm struggling to get association right on Grails. Let's say I have two domain classes: class Engine { String name int numberOfCylinders = 4 static constraints = { name(blank:false, nullable:false) numberOfCylinders(range:4..8) } } class Car { int year String brand Engine engine = new Engine(name:"Default Engine") static constraints = { engine(nullable:false) brand(blank:false, nullable:false) year(nullable:false) } } The idea is that users can create cars without creating an engine first, and those cars get a default engine. In the CarController I have: def save = { def car = new Car(params) if(!car.hasErrors() && car.save()){ flash.message = "Car saved" redirect(action:index) }else{ render(view:'create', model:[car:car]) } } When trying to save, I get a null value exception on the Car.engine field, so obviously the default engine is not created and saved. I tried to manually create the engine: def save = { def car = new Car(params) car.engine = new Engine(name: "Default Engine") if(!car.hasErrors() && car.save()){ flash.message = "Car saved" redirect(action:index) }else{ render(view:'create', model:[car:car]) } } Didn't work either. Is Grails not able to save associated classes? How could I implement such feature?

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  • Python - Access a class from a list using a key

    - by Fake Name
    Is there any way to make a list of classes behave like a set in python? Basically, I'm working on a piece of software that does some involved string comparison, and I have a custom class for handling the strings. Therefore, there is an instance of the class for each string. As a result, I have a large list containing all these classes. I would like to be able to access them like list[key], where in this case, the key is a string the class is based off of. It seems to me that I sould be able to do this somewhat easily, by adding something like __cmp__ to the class, but either I'm being obtuse (likely), or Im missing someting in the docs. Basically, I want to be able to do something like this (Python prompt example): >>class a: ... def __init__(self, x): ... self.var = x ... >>> from test import a >>> cl = set([a("Hello"), a("World"), a("Pie")]) >>> print cl set([<test.a instance at 0x00C866C0>, <test.a instance at 0x00C866E8>, <test.a instance at 0x00C86710>]) >>> cl["World"] <test.a instance at 0x00C866E8> Thanks!

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  • including pre-built java classes into an android project

    - by moonlightcheese
    i'm trying to include a maven java project into my android project. the maven project is the greader-unofficial project which allows developers access to google reader accounts, and handles all of the http transactions and URI/URL building, making grabbing feeds and items from google reader transparent to the developer. the project is available here: http://code.google.com/p/greader-unofficial/ the code is originally written for the standard jdk and uses classes from java.net that are not a part of the standard Android SDK. i actually tried to manually resolve all dependencies and ran into a problem when i got as far as including com.sun.syndication pieces required by the class be.lechtitseb.google.reader.api.util.AtomUtil.java... some of the classes in java.net that are in the standard jdk (i'm using 1.6) are not in the Android SDK. in addition, resolving all of these dependencies manually is just ridiculous when i'm compiling a maven project that should be pretty simple. however, i can use maven to compile the sources with no issue. how can i include this maven project, which is dependent on the complete jdk, into my android project in such a way that it will compile so that i can access the GoogleReader class from my android project? and for the record, i don't have the expertise to rewrite this entire api to work with the standard Android SDK.

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  • Does Entity Framework saves related classes automatically?

    - by herbatnic
    Let's assume that we have such classes public class A{ string someField { get; set; } public virtual B B {get; set; } } public class B { int someIntField {get; set; } [ForeignKey("Id")] [Required] public virtual A A { get; set; } } In code I create new instances for both of them and making relation like: A a = new A () { someField = "abcd"}; B b = new B () { someIntField = 42 }; A.B = b; B.A = a; Should I using DBContext to save both classes like that: using (var db = new myDbContext()) { myDbContext.As.Add(A); myDbContext.Bs.Add(B); myDBContext.SaveChanges(); } Or saving it like that: using (var db = new myDbContext()) { myDbContext.As.Add(A); myDbContext.SaveChanges(); } is enough to store related objects into database?

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  • Classes in same package

    - by nicholas_r
    I love the Intellij IDEA but i have been stacked on one little problem with Java imports. So for example there is a package with name "example" and two different classes in it: A.java and B.java. And i wanna get access to class "A" from class "B" without imports. Like this: class A: package example; public class A{ ... some stuff here ...} class B: package example; public class B{ public static void main(String[] args){ A myVar = 1234; } } This code may not work, but it's doesn't matter. Trouble just with IDE and with its mechanism of importing classes. So, problem is that i can't see A class from B. Idea says 'Cant resolve symbol' but i actually know that class A exists in package. Next strange is that complier works fine and there are no exceptions. Just IDEA can't see the class in the same package. Does anybody has any ideas?

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