overriding

问题 I'm not able to override some builtin functions, such as '__setitem__', in Python2.7 (although the same occurs in previous versions I tested) Although I know this is easy to do via subclassing, this is not what I want here, I need to be able to dynamically override these methods. Apparently, when my class is a subclass of ' object ', the overridden method always ends up calling the original one, but when my class is not an ' object ', it works: >>> def new_implementation(k, v): ... print 'New

问题 I want to override class(Product.php) file using my module. If i put it in root/override/classes/Product.php then it is working. But I want to put it in modules/my_module/override/classes/Product.php Then it is not working for me. If anyone done something like this then please let me know how can I do that ? Thanks. 回答1: The location that you put the file is the correct one. Note that the file must be there before you install the module. Putting it there after it's installed will do nothing,

问题 Did I dream this? I could have swore I read something about java 7 supplying an annotation that you could place on a method to ensure all subclasses call super. Has this been renamed, or dropped, or was it never actually considered? 回答1: It was part of JSR 305: Annotations for Software Defect Detection and called @OverridingMethodsMustInvokeSuper. The JSR is inactive, but a reference implementation is available bundled with FindBugs 回答2: It could have been suggested for project Coin, which

问题 I want to override ToString() on IEnumerable<Int32> . I was thinking to use Extension methods. But when I do this below, it still calls the ToString() on System.Object . When I rename my method, then it calls my method. As my extension method is in a static class, I am not able to override. How can I achieve this so that my ToString() implementation is called when I call .ToString() on List<Int32> for example? public static class ExtensionMethods { public static new string ToString(this

问题 I have a base class with a virtual method, and multiple subclasses that override that method. When I encounter one of those subclasses, I would like to call the overridden method, but without knowledge of the subclass. I can think of ugly ways to do this (check a value and cast it), but it seems like there should be an in-language way to do it. I want the List to contain multiple subclasses within the same list, otherwise obviously I could just make a List. EDIT: Fixed the comment in the code

问题 I've a base class with a virtual function: TMyBaseClass = class(TObject) public ValueOne : integer; procedure MyFunction(AValueOne : integer); virtual; end; procedure TMyBaseClass.MyFunction(AValueOne : integer); begin ValueOne := ValueOne; end; A descendant class implements a function with the same name. This function adds a new param and calls its anchestor's function. TMyDerivedClass = class(TMyBaseClass) public ValueTwo : integer; procedure MyFunction(AValueOne : integer; AValueTwo :

问题 According to the Telescope example (source code), it is possible to display a custom accounts-ui form (see his user_signin.html) and use {{loginButtons}} (see his nav.html) to keep the other things by default from Accounts-UI package . I am looking for 2 hours how this is possible. Any idea how to achieve this? 回答1: You can configure the Accounts UI with Accounts.ui.config. For example: Accounts.ui.config({ requestPermissions: { facebook: ['user_likes'], github: ['user', 'repo'] },

问题 I want to override the back button when the soft keyboard is shown. Basically when the back button is hit, I want the keyboard to dismiss, and I want to append some text onto whatever the user has typed in that edit text field. So basically I need to know when the keyboard is dismissed. After searching around, I realized there is no API for this, and that the only real way to do this would be to make your EditText class. So I created my own EditText class and extended EditText like this

问题 Edit : solved! Will update shortly with a solution. Aim: I want to rewrite Python's UnitTest module so when I call it I get the following JSON output within the stdout stream. For example: { "errors":0, "failures":1, "ran":3, "skipped":0, "successful":2, "test_data":[ { "index":0, "result":1 }, { "index":1, "result":1 }, { "index":2, "result":-1 } ] } Problem: I've written some code to generate these test results, but I'm facing problems with writing code for the test_data attribute of the

问题 I have 1 Main View and 1 SubView : Main View > SubView I think that the Main View is "stealing" the events from the SubView . For example, when I tap on the SubView , only the Main View GestureRecognizer is fire. Here is my custom GestureRecognizer (which intercepts every touch event): import UIKit import UIKit.UIGestureRecognizerSubclass class MainGestureRecognizer: UIGestureRecognizer { override func touchesBegan(touches: NSSet!, withEvent event: UIEvent!) { super.touchesBegan(touches,