interface

问题 Can somebody explains how to use the GWT cell tree. I am trying to google it but not finding any valuable tutorial?? Thanks 回答1: Try; Google Example 1 includes onModuleLoad method. :) 回答2: For those who don't like the google showcase example like me can use this example; http://google-web-toolkit.googlecode.com/svn/javadoc/2.1/com/google/gwt/user/cellview/client/CellTree.html you can just copy paste it and it works. " Trivial example public class CellTreeExample implements EntryPoint { /** *

问题 let's have this code : class MyList : IEnumerable, IEnumerator { int[] A = { 1, 2, 3, 4, 5 }; int i = -1; #region IEnumerator Members public object Current { get { return A[i]; } } public bool MoveNext() { i++; return i < 5; } public void Reset() { i = -1; } #endregion #region IEnumerable Members public IEnumerator GetEnumerator() { return (IEnumerator)this; } #endregion } And In Main Method : MyList list = new MyList(); foreach (int i in list) { Console.WriteLine(i); } foreach (int i in list

问题 I've never been able to figure this out. If your language doesn't type-check, what benefits do interfaces provide you? 回答1: Interfaces cause your program to fail earlier and more predictably when a subclass "forgets" to implement some abstract method in its parent class. In PHP's traditional OOP, you had to rely on something like the following to issue a run-time error: class Base_interface { function implement_me() { assert(false); } } class Child extends Base_interface { } With an interface

问题 I'am new to GraphQL but I really like it. Now that I'am playing with interfaces and unions, I'am facing a problem with mutations. Suppose that I have this schema : interface FoodType { id: String type: String composition: [Ingredient] } type Pizza implements FoodType { id: String type: String pizzaType: String toppings: [String] size: String composition: [Ingredient] } type Salad implements FoodType { id: String type: String vegetarian: Boolean dressing: Boolean composition: [Ingredient] }

问题 I have an interface defined as: public interface MyInterface { object foo { get; set; }; } and a class that implements that interface: public class MyClass : MyInterface { object foo { get; set; } } I then create a function that returns a ICollection like so: public ICollection<MyClass> Classes() { List<MyClass> value; List<MyInterface> list = new List<MyInterface>( new MyInterface[] { new MyClass { ID = 1 }, new MyClass { ID = 1 }, new MyClass { ID = 1 } }); value = new List<MyClass>(

问题 I have a question about interface and class implementing interface. This is my code: interface iMyInterface { public iMethod1(); } public class cMyClass implements iMyInterface { public iMethod1() { // some code } protected iMethod2() { // some code } } I would like to create an instance of iMyInterface as this : iMyInterface i = new cMyClass(); i.iMethod1(); It's ok, but how can I call iMethod2() from my interface instance? Is this working and safe: ((cMyClass)i).iMethod2(); Thanks for help.

问题 When I see code snippets like interface A { void a(); void b() default { System.out.println("b"); }; void c() final { System.out.println("c"); }; } I have one question. Haven't we already got enough sh*t in Java? Why one might need this? 回答1: I suggest you to look at this conference : http://medianetwork.oracle.com/media/show/16999 This explain everything. The most interesting thing to do is to allow an interface to evolve without rewritting your whole codebase. This is key to allow a big

问题 I'm trying to create an interface to a common class, but the implementation classes can have different parameters. e.g. public interface IViewModel { //... void ResetReferences(); } // and then, in my class implementations, something like this: public class LocationViewModel : IViewModel { public void ResetReferences(List<StateProvinces> stateProvinces) //... } public class ProductViewModel : IViewModel { public void ResetReferences(List<Color> colors, List<Size> sizes) //... } So notice that

问题 I'm using an interface to ensure some similar classes implements some mandatory methods (subs/functions). Example: interface I1 declares M1 and M2 methods C1 and C2 implement I1, and have their own versions for M1 and M2. C1 and C2 also need methods that are exactly the same, for example methods SM1 and SM2. To avoid repeating SM1 and SM2 I'd like to define an abstract class AC: implementing I1 defining SM1 and SM2. which would be extended by C1 and C2 This solution is indeed possible in Java

问题 In java when an interface extends another interface: Why does it implement its methods? How can it implement its methods when an interface can't contain a method body How can it implement the methods when it extends the other interface and not implement it? What is the purpose of an interface implementing another interface? This has major concepts in Java! EDIT: public interface FiresDragEvents { void addDragHandler(DragHandler handler); void removeDragHandler(DragHandler handler); } public