constructor

问题 In most Android apps, onCreate() is overridden with the first bit of code being super.onCreate(savedInstanceState) and I know this gathers the savedInstanceState Bundle and is neccessary for compilation but what about all of the constructors? onResume() , onStop() , onStop() etc. Which overridden methods have important super constructors you need to include? Is there a list somewhere? I see the super constructors included in some code, not in others.. I have included them sometimes myself,

问题 I have 10 actions in one Controller. Every action required ID from request. I want to check ID in constructor for every action, so I want avoid to write the same code 10 times in every action. obviously, In constructor I can not use functions like: $this->params()->fromQuery('paramname'); or $this->params()->fromRoute('paramname'); So, the question is how to get request params in controller's constructor? 回答1: Short answer: you cannot. The plugins (you are using params here) are available

问题 Given the (overly simplified) snippet: import Validator from 'validator'; export default function isValid(arg) { // Validator#isValid is an ES6 getter return new Validator(arg).isValid; } How can I test that a Validator was instantiated with the given parameter? And stub isValid ? I know I can restructure my code to avoid the issue, I am not looking for a workaround as I found plenty (dependency injection, not using ES6 sugar, etc.). I found a way, but it is terribly ugly. In test file:

问题 Problem: I have a non-copyable object with two constructors. I need to create an object with one of the constructors and then use it within some common code:- With a copyable object it would look like this, and be easy: Object a; if (condition) a = Object(p1); else a = Object(p2,p3,p4); a.doSomething(); But, the object is non-copyable, so I've had to do this: boost::scoped_ptr<Object> a; if (condition) a = new Object(p1); else a = new Object(p2,p3,p4); a->doSomething(); This feels too complex

问题 I try to write my own loader-class which loads an encryted class. Therefore I also override the contruction loader(ClassLoader paramClassLoader, File paramFile) , which calls super(new URL[] { paramFile.toURI().toURL() }, paramClassLoader); . The call ".toUrl()" can throw an MalformedURLException , so compiling the following code ... public class loader extends URLClassLoader { public static void main(String[] args)throws Exception{ Object localObject = new loader(loader.class.getClassLoader(

问题 public class Game { public Game( boolean createstage, //For sorting purposes int slength, int sheight, boolean createplayer, int plength, int pheight, boolean playersprite, BufferedImage psprite, boolean defaultcontrols, String pcontrols, boolean test ) { if(test == true) { //if test is true, test new Test(); }else{ //otherwise create a stage is createstage is true and if(createstage == true) { StageObj gamestage = new StageObj(slength, sheight); } if(createplayer==true) { PlayerObj player =

问题 In python 3 I found that class attribute can be used as a argument in __init__() function, like below: file test.py: class Foo: var1 = 23333 def __init__(self, var=var1): self.var = var run in cmd: C:\Users\rikka\Desktop>py -3 -i test.py >>> f1=Foo() >>> f1.var 23333 but by using a dot.expression, when init this class, interpreter will report an error: file test2.py: class Foo: var1 = 23333 def __init__(self, var=Foo.var1): self.var = var run in cmd: C:\Users\rikka\Desktop>py -3 -i test2.py

问题 I'm new to Angular/Node and cannot seem to figure out a problem I'm having. I'm trying to connect to an ftp using client-ftp and am having trouble with the implementation. Essentially I'm creating a button on the front end like this: <button class="btn btn-primary" (click)="downloadFile()"><i class="fa fa-file-photo-o"></i> Download Screenshot</button> And implementing trying to implement it via a click event like this: downloadFile(){ console.log('Connecting to sftp...'); var ftpClient =

问题 This question already has answers here : Referring to class names through strings? (5 answers) Closed 6 years ago . I have the following variable: var = 'MyClass' I would like to create an object of MyClass based on the variable var . Something like var() . How can I do this in Python? 回答1: >>> def hello(): ... print "hello world" ... >>> globals()["hello"]() hello world 回答2: Presuming you have the class' module as a variable as well, you can do the following, where the class you want

问题 This question already has answers here : Why does the default parameterless constructor go away when you create one with parameters (11 answers) Closed 6 years ago . In C# when I create an empty class it provides a default constructor however when I provide a constructor with parameters the default constructor is no longer created. My questions are: why does the compiler no longer give me the default constructor as well? Is there a setting so that this default constructor is always generated?