overriding

问题 I have an upper class that has a var title and then I have different classes, that extend this upper one, in which I want to override that var title . I was trying with @override void set method, but I didn't understand how to use it properly. Can someone help me please? 回答1: You can use getter and setter combined with super to achieve the desired result: class Foo { String title; } class Override extends Foo { String get title { print("get title"); return super.title; } set title(value) {

问题 I'm trying to understand whether the answer to the following question is the same in all major OOP languages; and if not, then how do those languages differ. Suppose I have class A that defines methods act and jump ; method act calls method jump . A 's subclass B overrides method jump (i.e., the appropriate syntax is used to ensure that whenever jump is called, the implementation in class B is used). I have object b of class B . I want it to behave exactly as if it was of class A . In other

问题 I am developing an Android application which makes use of the ScanResult object. This object is in the form of: [SSID: __mynetwork__, BSSID: 00:0e:2e:ae:4e:85, capabilities: [WPA-PSK-TKIP][ESS], level: -69, frequency: 2457, timestamp: 117455824743] I am trying to override the equals() method of this class by creating my own class which extends ScanResult : public class MyScanResult extends ScanResult { public MyScanResult() { super(); } @Override public boolean equals(Object o) { if (this ==

问题 I'm trying to customize a Joomla template, which is based on Bootstrap. Specifically, I'm trying to make a "hardcoded" .span4 have the width of a .span3. Sure, it would be much easier to change the markup, but I think that's what css is for, despite the way most of us use Bootstrap for defining layout and visual appearance. Besides, where would be the fun of learning? For that, this is what I'm trying in the my_css.less provided with the template: .row-fluid #top1.span4 { .row-fluid .span(3);

问题 For example item price is £6.78 postage and packaging should be: Single copy: £1.50 2-3 copies £3.00 4-6 copies: £4.00 7-8 copies: £5.00 9 copies: £6.00 10 or more free Any idea how I can do this? The current code for the item is: <form target="paypal" action="https://www.paypal.com/cgi-bin/webscr" method="post"> <input type="hidden" name="cmd" value="_s-xclick"> <input type="hidden" name="hosted_button_id" value="CUWB7BQEL337J"> <input type="image" src="https://www.paypalobjects.com/en_GB/i

问题 I'm using an analytics tool which logs the accessibilityLabel of buttons. I'm trying to find a way to update the accessibilityLabel without changing my existing code. For normal buttons I use the titleLabel.text . For iconButtons which use their the name coming from image assets I use accessibilityLabel itself. Some issues I faced: can't access accessibilityLabel within its getter. Because that would recursively look for accessibilityLabel . So I had to use another property for backing and

问题 I'm using SonataUserBundle with FOSUserBundle. in AppKernel.php it looks like this: new FOS\UserBundle\FOSUserBundle(), new Sonata\UserBundle\SonataUserBundle('FOSUserBundle'), new Application\Sonata\UserBundle\ApplicationSonataUserBundle(), Some controllers from SonataUserBundle are already overriden. Now I want to overridee FOSUserBundle ChangePasswordController. So I made: src/Application/FOS/UserBundle/Controller/ChangePasswordController.php src/Application/FOS/UserBundle

问题 I have an actor that is mysteriously dying, and I think the cause may be that someone is sending the actor a PoisonPill. Is there a way for me to override the behavior of an actor when it receives a PoisonPill so that it logs the sender and the fact that it just received a PoisonPill? That is, of course, in addition to stopping the actor. I am using 2.4.16, and in this version, PoisonPill behavior appears to be defined in a class called ActorCell. The problem is that this class is private and

问题 I am unable to override Sales Rule Model. I want to override class Mage_SalesRule_Model_Rule . Here is my code:- <?xml version="1.0"?> <config> <modules> <MyNamespace_MyModule> <version>0.1.0</version> </MyNamespace_MyModule> </modules> <global> <models> <salesrule> <rewrite> <rule>MyNamespace_MyModule_Model_Rule</rule> </rewrite> </salesrule> </models> </global> </config> But this doesn’t work. Any help please? 回答1: Thank you all for helping in debugging my problem. The problem is solved now

问题 ObjectPropertyBase skips value invalidation when newValue == oldValue : /** * {@inheritDoc} */ @Override public void set(T newValue) { if (isBound()) { throw new java.lang.RuntimeException((getBean() != null && getName() != null ? getBean().getClass().getSimpleName() + "." + getName() + " : ": "") + "A bound value cannot be set."); } if (value != newValue) { value = newValue; markInvalid(); } } Problem: markInvalid() and value are private , therefore I cannot override set(newValue) properly.