composition

问题 Lets say I have a parent class class parent { } ..... This parent has three sub class class child1 { } class child2 { } class child3 { } and these child classes have further smaller parts like class child1subpar1 { } class child1subpar2 { public function foo() { echo "hi"; } } class child2subpar1 { } class child2subpar2 { } Now, how to sum this whole up like class child1 extends child1subpar1, child1subpar2 { } class child2 extends child2subpar1, childsubpar1 { } class parent extends child1

问题 I'm looking for documentation regarding WPF best practice for Compositing and agregating the user interface in a large project. I'm comming from a visual Inheriance world using Delphi and Winform. And I'm now try to replicate that kind of pattern well in fact reusability of those UI elements. I'm open to suggestion and reading. 回答1: The Composite Application Guidance (sometimes called "Prism") is appropriate, especially if the application has a lot of moving parts developed by different teams

问题 I have a class A and Class B . Class C derives from Class B and has Class A object as composition . http://ideone.com/JGT48M #include "iostream" using namespace std; class A { int i; public: A(int ii) : i(ii) { cout << "\n Constructor of A is called \n"; } ~A() { cout << "\n destructor of A is called \n"; } void f() const {} }; class B { int i; public: B(int ii) : i(ii) { cout << "\n Constructor of B is called \n"; } ~B() { cout << "\n destructor of B is called \n"; } void f() const {} };

问题 I have a UWP app, which I should start by pointing out that it uses very little XAML. The views are built from JSON object recieved from an API. This means that the vast majority of everything is done in C#, and therefore adds a little complexity to my problem. I basically want to have a panel (e.g. Grid) that can have rounded corners and have a drop shadow applied to it. The drop shadow should also have the rounded corners, this can be seen in the sample below. I have looked at the

问题 How can I apply an effect to a ListView where the top 30px graduate from fully transparent to fully opaque? The idea is that as you scroll down, the top items gradually fade away. I am building a UWP application where the design calls for the top 30px of a ListView to start at opacity 0 and transition to opacity 1. Conceptually I am imagining an Opacity Mask that would be applied to the top part of a SpriteVisual but I cannot work out how to achieve this. I am attempting this using the the

问题 I have a AggregateCatalog that contains an AssemblyCatalog and a DirectoryCatalog. I want them to work like this: If both catalogs can find an export, choose the one from the DirectoryCatalog. If neither of them can find an export, then just leave the import to be null. If only one of them can find an export, then just use that export to fill the import. How can I achieve something like this? 回答1: You can achieve point 1. and 3. by putting the catalogs in different export providers, and then

问题 I have a few (fairly redundant) queries in my app that are something like this: var last30Days = DateTime.Today.AddDays(-30); from b in Building let issueSeverity = (from u in Users where u.Building == b from i in u.Issues where i.Date > last30Days select i.Severity).Max() select new { Building = b, IssueSeverity = issueSeverity } And: var last30Days = DateTime.Today.AddDays(-30); from c in Countries let issueSeverity = (from u in Users where u.Building.Country == c from i in u.Issues where i

问题 I'm dealing with this problem. I'm creating math problems, each one has response. For example. If my question is about the "result of 5x + 15 = 2?" , I'll be waiting just one answer (as integer). If my question is about says "give me the area and permiter of this shape" , I'll be waiting two answers (as doubles). In another one, I'll be waiting as response a string And anothers, I can have several answers or responses with various datatypes. My big question is. How would be the relation

问题 All the monad articles often state, that monads allow you to sequence effects in order. But what about simple composition? Ain't f x = x + 1 g x = x * 2 result = f g x requires g x to be computed before f ... ? Do monads do the same but with handling of effects? 回答1: Disclaimer : Monads are a lot of things. They are notoriously difficult to explain, so I will not attempt to explain what monads are in general here, since the question does not ask for that. I will assume you have a basic grasp

问题 I need to know if it's possible to add some attributes and behaviours to some POJO JPA entity (using hibernate provider) by extending it, and then to make entityManager to return extended objects instead of just pojo entitys, like the following examples: POJO JPA Entity Class @Entity @Table("test") public class Test implements Serializable { } Extended Class public class ExtendedTest extends Test { ... } Fetching Extended Class's objects List<ExtendedTest> extendedList = entityManager