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  • IE: position two text lines on top and bottom corners in table cell?

    - by diggonce
    I have a table with dynamic data. And there is a specific line of text which should be displayed only when a user hovers over the table row. This line of text should be 'fixed' to the table cell's bottom edge. It works so far with Firefox, but fails in IE. Live code can be seen here: http://2010resolutions.org/test/index.html The text in red should be fixed to the table cell's bottom border. (They will have a fixed height and width) Any clues how to get this working in IE? Any help is appreciated. Here's the code: <style> table { width: 500px; background: gray; } td { vertical-align: top; } .wrapper { position: relative; background: green; } tr, td, .wrapper { height: 100%; padding-bottom: 0.75em; } .bottom { position: absolute; left: 0; bottom: 0; background: red; } .bottom { visibility: hidden; } tr:hover .bottom { visibility: visible; } </style> <table> <tr class="data"> <td> <div class="wrapper"> This is line 1<br /> This is line 2<br /> This is line 3<br /> <span class="bottom">Bottom line 1</span> </div> </td> <td> <div class="wrapper"> This is line 4<br /> This is line 5<br /> This is line 6<br /> <span class="bottom">Bottom line 2</span></span> </div> </td> <td> <div class="wrapper"> This is line 7<br /> This is line 8<br /> This is line 9<br /> This is line 10<br /> This is line 11<br /> This is line 12<br /> <span class="bottom">Bottom line 3</span> </div> </td> </tr> <tr> <td>&nbsp;</td> <td>&nbsp;</td> <td>&nbsp;</td> </tr> </table>

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  • Is there a way to do this with basic JS DOM?

    - by Thomas
    I need to apply/remove to an input field according to a user's selection in a separate drop down form - but I can't figure out how to target the input's class. I need to add/remove the 'pageRequired' class from this input: <input type="text" title="Company Required" name="customfields-tf-2-tf" class="inputclass pageRequired textInput" id="customfields-tf-2-tf" /> When the user selects one of two options from a drop down field. For example: <select class="dropdown" name="customfields-s-1-s" id="customfields-s-1-s" > <option value="Owner"<?php if(in_array("Owner",$temp_values)) { ?> selected='selected'<?php } ?>> Owner</option> <option value="Broker"<?php if(in_array("Broker",$temp_values)) { ?> selected='selected'<?php } ?>> Broker</option> </select> If the user selects broker than I want to add the pageRequired class to the first input field and remove it if the user selects Owner.

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  • How to mock static member variables

    - by pkrish
    I have a class ClassToTest which has a dependency on ClassToMock. public class ClassToMock { private static final String MEMBER_1 = FileReader.readMemeber1(); protected void someMethod() { ... } } The unit test case for ClassToTest. public class ClassToTestTest { private ClassToMock _mock; @Before public void setUp() throws Exception { _mock = mock(ClassToMock.class) } } When mock is called in the setUp() method, FileReader.readMemeber1(); is executed. Is there a way to avoid this? I think one way is to initialize the MEMBER_1 inside a method. Any other alternatives? Thanks!

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  • How get divs count in jquery?

    - by Pandiya Chendur
    I used this jquery each function and iterated my json data with it.... $.each(data.Results, function() { divs += '<div class="resultsdiv"><br /> <span style="display: inline-block;width:150px;" class="resultName">' + this.Mat_Name + '</span><span class="resultfields" style="padding-left:10px;"> Measurement&nbsp;:</span>&nbsp;<span class="resultfieldvalues">' + this.Mes_Name + '</span>&nbsp;<a href="/Materials/Delete/' + this.Id + '"> Delete</a>&nbsp;<a href="/Materials/Details/' + this.Id + '">Details</a>&nbsp; <a href="/Materials/Edit/' + this.Id + '">Edit</a></div>'; }); alert(divs.length); doesnt seem to get the count.... Any suggestion...

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  • Access asp:CheckBox inner input from jQuery

    - by abatishchev
    I have a jQuery array acting on each control having corresponding class: function Foobar() { $('.foo').each(function() { // do something with $(this) } } I can access client-side controls like <input class="foo"> and server-side controls like asp:TextBox CassClass="foo"> But setting CssClass for asp:RadioButton doesn't make a sense. Here is generated code: <span class="foo"> <input type="radio" /> </span> How to set class for inner input or another way gather it using jQuery?

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  • Dynamic swappable Data Access Layer

    - by Andy
    I'm writing a data driven WPF client. The client will typically pull data from a WCF service, which queries a SQL db, but I'd like the option to pull the data directly from SQL or other arbitrary data sources. I've come up with this design and would like to hear your opinion on whether it is the best design. First, we have some data object we'd like to extract from SQL. // The Data Object with a single property public class Customer { private string m_Name = string.Empty; public string Name { get { return m_Name; } set { m_Name = value;} } } Then I plan on using an interface which all data access layers should implement. Suppose one could also use an abstract class. Thoughts? // The interface with a single method interface ICustomerFacade { List<Customer> GetAll(); } One can create a SQL implementation. // Sql Implementation public class SqlCustomrFacade : ICustomerFacade { public List<Customer> GetAll() { // Query SQL db and return something useful // ... return new List<Customer>(); } } We can also create a WCF implementation. The problem with WCF is is that it doesn't use the same data object. It creates its own local version, so we would have to copy the details over somehow. I suppose one could use reflection to copy the values of similar fields across. Thoughts? // Wcf Implementation public class WcfCustomrFacade : ICustomerFacade { public List<Customer> GetAll() { // Get date from the Wcf Service (not defined here) List<WcfService.Customer> wcfCustomers = wcfService.GetAllCustomers(); // The list we're going to return List<Customer> customers = new List<Customer>(); // This is horrible foreach(WcfService.Customer wcfCustomer in wcfCustomers) { Customer customer = new Customer(); customer.Name = wcfCustomer.Name; customers.Add(customer); } return customers; } } I also plan on using a factory to decide which facade to use. // Factory pattern public class FacadeFactory() { public static ICustomerFacade CreateCustomerFacade() { // Determine the facade to use if (ConfigurationManager.AppSettings["DAL"] == "Sql") return new SqlCustomrFacade(); else return new WcfCustomrFacade(); } } This is how the DAL would typically be used. // Test application public class MyApp { public static void Main() { ICustomerFacade cf = FacadeFactory.CreateCustomerFacade(); cf.GetAll(); } } I appreciate your thoughts and time.

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  • C++: inheritance problem

    - by Helltone
    It's quite hard to explain what I'm trying to do, I'll try: Imagine a base class A which contains some variables, and a set of classes deriving from A which all implement some method bool test() that operates on the variables inherited from A. class A { protected: int somevar; // ... }; class B : public A { public: bool test() { return (somevar == 42); } }; class C : public A { public: bool test() { return (somevar > 23); } }; // ... more classes deriving from A Now I have an instance of class A and I have set the value of somevar. int main(int, char* []) { A a; a.somevar = 42; Now, I need some kind of container that allows me to iterate over the elements i of this container, calling i::test() in the context of a... that is: std::vector<...> vec; // push B and C into vec, this is pseudo-code vec.push_back(&B); vec.push_back(&C); bool ret = true; for(i = vec.begin(); i != vec.end(); ++i) { // call B::test(), C::test(), setting *this to a ret &= ( a .* (&(*i)::test) )(); } return ret; } How can I do this? I've tried two methods: forcing a cast from B::* to A::*, adapting a pointer to call a method of a type on an object of a different type (works, but seems to be bad); using std::bind + the solution above, ugly hack; changing the signature of bool test() so that it takes an argument of type const A& instead of inheriting from A, I don't really like this solution because somevar must be public.

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  • c++ polymorphism and other function question

    - by aharont
    i have got this code: class father{ public: virtual void f() { cout<<1;} }; class son:public father{ public: void f() {cout<<2;} }; void test (father x){x.f();} int main(){ son s; test(s); } the question says: the output is '1', what is the rule about polymorphism that the programmer forgot and how can i fix it so the output would be '2'? there is another rule that the programmer forgot when he wrote the father class, and he need to add an empty function to avoid problems from other sons of the father class. what is the rule and what is the missing function? another question write the g function so the next code would run with no crashes int x=11; g(x)=22;

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  • in vb.net an error is coming

    - by user275111
    Compiler Error Message: ASPNET: Make sure that the class defined in this code file matches the 'inherits' attribute, and that it extends the correct base class (e.g. Page or UserControl). in vb code-i used namespace and a class.

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  • Comparing objects and inheritance

    - by ereOn
    Hi, In my program I have the following class hierarchy: class Base // Base is an abstract class { }; class A : public Base { }; class B : public Base { }; I would like to do the following: foo(const Base& one, const Base& two) { if (one == two) { // Do something } else { // Do something else } } I have issues regarding the operator==() here. Of course comparing an instance A and an instance of B makes no sense but comparing two instances of Base should be possible. (You can't compare a Dog and a Cat however you can compare two Animals) I would like the following results: A == B = false A == A = true or false, depending on the effective value of the two instances B == B = true or false, depending on the effective value of the two instances My question is: is this a good design/idea ? Is this even possible ? What functions should I write/overload ? My apologies if the question is obviously stupid or easy, I have some serious fever right now and my thinking abilities are somewhat limited :/ Thank you.

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  • How do I set up Array/List dependencies in code with Castle Windsor?

    - by SharePoint Newbie
    Hi, I have the following classes: class Repository : IRepository class ReadOnlyRepository : Repository abstract class Command abstract CommandImpl : Command { public CommandImpl(Repository repository){} } class Service { public Service (Command[] commands){} } I register them in code as follows: var container = new Container("WindsorCOntainer.config"); var container = new WindsorContainer(new XmlInterpreter("WindsorConfig.xml")); container.Kernel.Resolver.AddSubResolver(new ArrayResolver(container.Kernel)); container.AddComponent("repository", typeof(RentServiceRepository)); container.Resolve<RentServiceRepository>(); container.AddComponent("command", typeof(COmmandImpl)); container.AddComponent("rentService", typeof (RentService)); container.Resolve<RentService>(); // Fails here I get the message that "RentService is waiting for dependency commands" What am I doing wrong? Thanks,

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  • Hibernate Annotation for Entity existing in more than 1 catalog

    - by user286395
    I have a Person entity mapped by Hibernate to a database table in a database catalog "Active". After a period of time, records in this database table in the "Active" catalog are archived/moved to an exact copy of the table in a database Catalog "History". I have the need to retrieve from both the Active and History Catalogs. Is there a better way to model this with Hibernate annotations than making an abstract class that 2 classes extend from. This is what I have now. @MappedSuperclass public abstract class Person { @Id private Integer id; private String name; } @Entity @Table(name="Person", catalog="Active") public class PersonActive extends Person { } @Entity @Table(name="Person", catalog="History") public class PersonHistory extends Person { }

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  • Django ModelForm Imagefield Upload

    - by Wei Xu
    I am pretty new to Django and I met a problem in handling image upload using ModelForm. My model is as following: class Project(models.Model): name = models.CharField(max_length=100) description = models.CharField(max_length=2000) startDate = models.DateField(auto_now_add=True) photo = models.ImageField(upload_to="projectimg/", null=True, blank=True) And the modelform is as following: class AddProjectForm(ModelForm): class Meta: model = Project widgets = { 'description': Textarea(attrs={'cols': 80, 'rows': 50}), } fields = ['name', 'description', 'photo'] And the View function is: def addProject(request, template_name): if request.method == 'POST': addprojectform = AddProjectForm(request.POST,request.FILES) print addprojectform if addprojectform.is_valid(): newproject = addprojectform.save(commit=False) print newproject print request.FILES newproject.photo = request.FILES['photo'] newproject.save() print newproject.photo else: addprojectform = AddProjectForm() newProposalNum = projectProposal.objects.filter(solved=False).count() return render(request, template_name, {'addprojectform':addprojectform, 'newProposalNum':newProposalNum}) the template is: <form class="bs-example form-horizontal" method="post" action="">{% csrf_token %} <h2>Project Name</h2><br> {{ addprojectform.name }}<br> <h2>Project Description</h2> {{ addprojectform.description }}<br> <h2>Image Upload</h2><br> {{ addprojectform.photo }}<br> <input type="submit" class="btn btn-success" value="Add Project"> </form> Can anyone help me or could you give an example of image uploading? Thank you!

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  • Undefined behaviour with non-virtual destructors - is it a real-world issue?

    - by Roddy
    Consider the following code: class A { public: A() {} ~A() {} }; class B: public A { B() {} ~B() {} }; A* b = new B; delete b; // undefined behaviour My understanding is that the C++ standard says that deleting b is undefined behaviour - ie, anything could happen. But, in the real world, my experience is that ~A() is always invoked, and the memory is correctly freed. if B introduces any class members with their own destructors, they won't get invoked, but I'm only interested in the simple kind of case above, where inheritance is used maybe to fix a bug in one class method for which source code is unavailable. Obviously this isn't going to be what you want in non-trivial cases, but it is at least consistent. Are you aware of any C++ implementation where the above does NOT happen, for the code shown?

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  • Find the right value in recursive array

    - by fire
    I have an array with multiple sub-arrays like this: Array ( [0] => Array ( [Page_ID] => 1 [Page_Parent_ID] => 0 [Page_Title] => Overview [Page_URL] => overview [Page_Type] => content [Page_Order] => 1 ) [1] => Array ( [0] => Array ( [Page_ID] => 2 [Page_Parent_ID] => 1 [Page_Title] => Team [Page_URL] => overview/team [Page_Type] => content [Page_Order] => 1 ) ) [2] => Array ( [Page_ID] => 3 [Page_Parent_ID] => 0 [Page_Title] => Funds [Page_URL] => funds [Page_Type] => content [Page_Order] => 2 ) [3] => Array ( [0] => Array ( [Page_ID] => 4 [Page_Parent_ID] => 3 [Page_Title] => Strategy [Page_URL] => funds/strategy [Page_Type] => content [Page_Order] => 1 ) [1] => Array ( [0] => Array ( [Page_ID] => 7 [Page_Parent_ID] => 4 [Page_Title] => A Class Fund [Page_URL] => funds/strategy/a-class-fund [Page_Type] => content [Page_Order] => 1 ) [1] => Array ( [0] => Array ( [Page_ID] => 10 [Page_Parent_ID] => 7 [Page_Title] => Information [Page_URL] => funds/strategy/a-class-fund/information [Page_Type] => content [Page_Order] => 1 ) [1] => Array ( [Page_ID] => 11 [Page_Parent_ID] => 7 [Page_Title] => Fund Data [Page_URL] => funds/strategy/a-class-fund/fund-data [Page_Type] => content [Page_Order] => 2 ) ) [2] => Array ( [Page_ID] => 8 [Page_Parent_ID] => 4 [Page_Title] => B Class Fund [Page_URL] => funds/strategy/b-class-fund [Page_Type] => content [Page_Order] => 2 ) I need a function to find the right Page_URL so if you know the $url is "funds/strategy/a-class-fund" I need to pass that to a function that returns a single array result (which would be the Page_ID = 7 array in this example). Having a bit of a stupid day, any help would be appreciated!

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  • where is "create instance" menu in visual studio 2010?

    - by austin powers
    Hi, in visual studio 2008 there is a sub-menu called "create instance" which is resides in class designer. Today I've opened VS.net 2010 and then opened class designer and create my class over there and when I wanted to test my class with the help of "create instance" option there was no such option available in vs.net 2010. and I've googled about it a little bit but no answer at all so I decided to mention about it here. where can I find this menu in vs.net 2010? regards.

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  • Why is this UL and inline JS giving errors during HTML validation?

    - by thor
    I've just run the homepage of a site I'm working on through the w3c HTML validator and it's come back with 3 errors and 2 warnings. I've taken a look at them but can't see why they would be causing a problem. I've pasted them in below (I've removed URL's/strings etc as the site isn't quite ready to be made public yet). This is being validated against XHTML Transitional by the way. The UL comes back with the following error: end tag for "ul" which is not finished <ul id='tabs'></ul> <ul id='tabs'> <li> <a href="/en/folder/folder/search?categories[]=cat1" class="tab1" title="tab_title"> <img alt="img_alt" src="img_src" /> <span> tab1_text </span> </a> </li> <li> <a href="/en/folder/folder/search?categories[]=cat2" class="tab2" title="tab_title"> <img alt="img_alt" src="img_src" /> <span> tab2_text </span> </a> </li> <li> <a href="/en/folder/folder/search?categories[]=cat3" class="tab3" title="tab_title"> <img alt="img_alt" src="img_src" /> <span> tab3_text </span> </a> </li> <li> <a href="/en/folder/folder/search?categories[]=cat4" class="tab4" title="tab_title"> <img alt="img_alt" src="img_src" /> <span> tab4_text </span> </a> </li> <li> <a href="/en/folder/folder/search?categories[]=cat5" class="tab5" title="tab_title"> <img alt="img_alt" src="img_src" /> <span> tab5_text </span> </a> </li> <li> <a href="/en/folder/folder/search?categories[]=cat6" class="tab6" title="tab_title"> <img alt="img_alt" src="img_src" /> <span> tab6_text </span> </a> </li> <li> <a href="/en/folder/folder/search?categories[]=cat7" class="tab7" title="tab_title"> <img alt="img_alt" src="img_src" /> <span> tab7_text </span> </a> </li> <li> <a href="/en/folder/folder/search?categories[]=cat8" class="tab8" title="tab_title"> <img alt="img_alt" src="img_src" /> <span> tab8_text </span> </a> </li> </ul> For the inline javascript, I'm getting 2 errors and 2 warnings all for the same thing - I have a simple if statement with && and the validator appears to be seeing this as HTML rather than javascript: character "&amp;" is the first character of a delimiter but occurred as data and xmlParseEntityRef: no name <script type='text/javascript'> if (weather_data != null && weather_data['data'] != null){ display_weather(); } </script> The javascript is placed just before the body close tag at the end of the document. If you need to see the full source then let me know and I can send it over.

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  • Getting list of fields back from 'use fields' pragma?

    - by makenai
    So I'm familiar with the use fields pragma in Perl that can be used to restrict the fields that are stored in a class: package Fruit; use fields qw( color shape taste ); sub new { my ( $class, $params ) = @_; my $self = fields::new( $class ) unless ref $class; foreach my $name ( keys %$params ) { $self->{ $name } = $params->{ $name }; } return $self; } My question is.. once I've declared the fields at the top, how I can get the list back.. say because I want to generate accessors dynamically? Is keys %FIELDS the only way? Secondarily, is there a more efficient way to pre-populate the fields in the constructor than looping through and assigning each parameter as I am above? Thanks!

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  • What do you name the "other" kind of view-model in an MVVM project?

    - by DanM
    With MVVM, I think of a view-model as a class that provides all the data and commands that a view needs to bind to. But what happens when I have a database entity object, say a Customer, and I want to build a class that shapes or flattens the Customer class for use in a data grid. For example, maybe this special Customer object would have a property TotalOrders, which is actually calculated using a join with a collection of Order entities. My question is, what do I call this special Customer class? In other situations, I'd be tempted to call it a CustomerViewModel, but I feel like "overloading" the notion of a view-model like this would be confusing in an MVVM project. What would you suggest?

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  • Grails Unique Constraint for Groups

    - by WaZ
    Hi there, I have the following requirement I have 3 domains namely: class Product { String productName static constraints = { productName(unique:true,blank:false) } class SubType { String subTypeName static constraints = { subTypeName(unique:true,blank:false) } String toString() { "${subTypeName}" } } class CLType { String TypeName static belongsTo = Car static hasMany = [car:Cars] static constraints = { } String toString() { "${TypeName}" } class CLines implements Serializable { Dealer dealer CLType clType SubType subType Product product static constraints = { dealer(nullable:false,blank:false,unique:['subType','product','clType']) clType(blank:false,nullable:false) subType(nullable:true) product(nullable:true) } } I want to achieve this combination: A user can assign dealer a CLType. But cannot have duplicates. As an example consider this scenario Please let me know what to mention in my unqiue constraint to make this possible? Thanks, Much Appreciated.

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  • Python: why can't descriptors be instance variables?

    - by Continuation
    Say I define this descriptor: class MyDescriptor(object): def __get__(self, instance, owner): return self._value def __set__(self, instance, value): self._value = value def __delete__(self, instance): del(self._value) And I use it in this: class MyClass1(object): value = MyDescriptor() >>> m1 = MyClass1() >>> m1.value = 1 >>> m2 = MyClass1() >>> m2.value = 2 >>> m1.value 2 So value is a class attribute and is shared by all instances. Now if I define this: class MyClass2(object) value = 1 >>> y1 = MyClass2() >>> y1.value=1 >>> y2 = MyClass2() >>> y2.value=2 >>> y1.value 1 In this case value is an instance attribute and is not shared by the instances. Why is it that when value is a descriptor it can only be a class attribute, but when value is a simple integer it becomes an instance attribute?

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  • What do I need to change to get this 'acts_as_rateable' Rails plugin working with this code from the

    - by tepidsam
    Hello! I'm working my way through the 'Foundation Rails 2' book. In Chapter 9, we are building a little "plugins" app. In the book, he installs the acts_as_rateable plugin found at http://juixe.com/svn/acts_as_rateable. This plugin doesn't appear to exist in 2010 (the page for this "old" plugin seems to be working again...it was down when I tried it earlier), so I found another acts_as_rateable plugin at http://github.com/azabaj/acts_as_rateable. These plugins are different and I'm trying to get the "new" plugin working with the code/project/app from the Foudations 2 book. I was able to use the migration generator included with the "new" plugin and it worked. Now,though, I'm a bit confused. In the book, he has us create a new controller to work with the plugin (the old plugin). Here's the code for that: class RatingsController < ApplicationController def create @plugin = Plugin.find(params[:plugin_id]) rating = Rating.new(:rating => params[:rating]) @plugin.ratings << average_rating redirect_to @plugin end end Then he had us change the routing: map.resources :plugins, :has_many => :ratings map.resources :categories map.root :controller => 'plugins' Next, we modified the following to the 'show' template so that it looks like this: <div id="rate_plugin"> <h2>Rate this plugin</h2> <ul class="star-rating"> <li> <%= link_to "1", @plugin.rate_it(1), :method => :post, :title => "1 star out of 5", :class => "one-star" %> </li> <li> <%= link_to "2", plugin_ratings_path(@plugin, :rating => 2), :method => :post, :title => "2 stars out of 5", :class => "two-stars" %> </li> <li> <%= link_to "3", plugin_ratings_path(@plugin, :rating => 3), :method => :post, :title => "3 stars out of 5", :class => "three-stars" %> </li> <li> <%= link_to "4", plugin_ratings_path(@plugin, :rating => 4), :method => :post, :title => "4 stars out of 5", :class => "four-stars" %> </li> <li> <%= link_to "5", plugin_ratings_path(@plugin, :rating => 5), :method => :post, :title => "5 stars out of 5", :class => "five-stars" %> </li> </ul> </div> The problem is that we're using code for a different plugin. When I try to actually "rate" one of the plugins, I get an "unknown attribute" error. That makes sense. I'm using attribute names for the "old" plugin, but I should be using attributes names for the "new" plugin. The problem is...I've tried using a variety of different attribute names and I keep getting the same error. From the README for the "new" plugin, I think I should be using some of these but I haven't been able to get them working: Install the plugin into your vendor/plugins directory, insert 'acts_as_rateable' into your model, then restart your application. class Post < ActiveRecord::Base acts_as_rateable end Now your model is extended by the plugin, you can rate it ( 1-# )or calculate the average rating. @plugin.rate_it( 4, current_user.id ) @plugin.average_rating #=> 4.0 @plugin.average_rating_round #=> 4 @plugin.average_rating_percent #=> 80 @plugin.rated_by?( current_user ) #=> rating || false Plugin.find_average_of( 4 ) #=> array of posts See acts_as_rateable.rb for further details! I'm guessing that I might have to make some "bigger" changes to get this plugin working. I'm asking this question to learn and only learn. The book gives code to get things working with the old plugin, but if one were actually building this app today it would be necessary to use this "new" plugin, so I would like to see how it could be used. Cheers! Any ideas on what I could change to get the "new" plugin working?

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  • Why is this Scala example of implicit paremeter not working?

    - by Alex R
    simple REPL test... def g(a:Int)(implicit b:Int) = {a+b} Why do neither of these attempted usages work? 1. scala class A { var b:Int =8; var c = g(2) } :6: error: could not find implicit value for parameter b: Int class A { var b:Int =8; var c = g(2) } 2. scala class A(var b:Int) { var c = g(2) } :6: error: could not find implicit value for parameter b: Int class A(var b:Int) { var c = g(2) } ^ Thanks

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  • When does logic belong in the Business Object/Entity, and when does it belong in a Service?

    - by Casey
    In trying to understand Domain Driven Design I keep returning to a question that I can't seem to definitively answer. How do you determine what logic belongs to a Domain entity, and what logic belongs to a Domain Service? Example: We have an Order class for an online store. This class is an entity and an aggregate root (it contains OrderItems). Public Class Order:IOrder { Private List<IOrderItem> OrderItems Public Order(List<IOrderItem>) { OrderItems = List<IOrderItem> } Public Decimal CalculateTotalItemWeight() //This logic seems to belong in the entity. { Decimal TotalWeight = 0 foreach(IOrderItem OrderItem in OrderItems) { TotalWeight += OrderItem.Weight } return TotalWeight } } I think most people would agree that CalculateTotalItemWeight belongs on the entity. However, at some point we have to ship this order to the customer. To accomplish this we need to do two things: 1) Determine the postage rate necessary to ship this order. 2) Print a shipping label after determining the postage rate. Both of these actions will require dependencies that are outside the Order entity, such as an external webservice to retrieve postage rates. How should we accomplish these two things? I see a few options: 1) Code the logic directly in the domain entity, like CalculateTotalItemWeight. We then call: Order.GetPostageRate Order.PrintLabel 2) Put the logic in a service that accepts IOrder. We then call: PostageService.GetPostageRate(Order) PrintService.PrintLabel(Order) 3) Create a class for each action that operates on an Order, and pass an instance of that class to the Order through Constructor Injection (this is a variation of option 1 but allows reuse of the RateRetriever and LabelPrinter classes): Public Class Order:IOrder { Private List<IOrderItem> OrderItems Private RateRetriever _Retriever Private LabelPrinter _Printer Public Order(List<IOrderItem>, RateRetriever Retriever, LabelPrinter Printer) { OrderItems = List<IOrderItem> _Retriever = Retriever _Printer = Printer } Public Decimal GetPostageRate { _Retriever.GetPostageRate(this) } Public void PrintLabel { _Printer.PrintLabel(this) } } Which one of these methods do you choose for this logic, if any? What is the reasoning behind your choice? Most importantly, is there a set of guidelines that led you to your choice?

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