initialization

问题 Closed . This question needs details or clarity. It is not currently accepting answers. Want to improve this question? Add details and clarify the problem by editing this post. Closed 6 years ago . public class A{ { System.out.println("hi i am IIB"); } public A(){ System.out.println("hi i am constructor"); } public static void main(String... args){ A objA=new A(); } } 回答1: iib will get execute before the constructor is called No, this is not what happens. The code written in instance

问题 JPanel p2 = new JPanel(new GridLayout(6,1)); ButtonGroup tubtype = new ButtonGroup(); JRadioButton roundrButton = new JRadioButton("Round", true); tubtype.add(roundrButton); JRadioButton ovalrButton = new JRadioButton("Oval", false); tubtype.add(ovalrButton); calcButton = new JButton("Calculate Volume"); exitButton = new JButton("Exit"); hlength = new JTextField(5); hwidth = new JTextField(5); hdepth = new JTextField(5); hvolume = new JTextField(5); lengthLabel = new JLabel("Enter the tub's

问题 I have init codes of both circle image and pop up image in App.xaml.cs. Only the first code is working, the code after Xamarin.Forms.Forms.Init is not working. My current code is adding below: //ImageCircle var rendererAssemblies = new[] { typeof(ImageCircleRenderer).GetTypeInfo().Assembly }; Xamarin.Forms.Forms.Init(e, rendererAssemblies); //Popup Rg.Plugins.Popup.Popup.Init(); Xamarin.Forms.Forms.Init(e, Rg.Plugins.Popup.Popup.GetExtraAssemblies()); Now image circle is working and pop up

问题 Is '\0' set automatically if I provide an extra element for it, but left it in the initialization string? Like: char a[6] = {"Hello"}; // <- Is NUL set here automatically? I´ve did one experiment with C and C++:` C: #include <stdio.h> int main() { char NEWYEAR[16] = {"Happy New Year!"}; printf("%s\n",NEWYEAR); return 0; } Output: Happy New Year! C++: #include <iostream> int main() { char NEWYEAR[16] = {"Happy New Year!"}; std::cout << NEWYEAR << std::endl; return 0; } Output: Happy New Year!

问题 Note The example code is an abridged version but can run with a basic function. Please focus on class MainWindow(tk.Frame) Questions What kind of object can play the role of the parent or master for tkinter class initialization? In my case, see the example code, why can not pass self as parent to ProjectInfo(...) or ConfirmItems(...) in class MainWindow(tk.Frame) ? It would pop up an empty window if using self instead of self.parent . Reference This question originates from my comments on

问题 I want to figure out the order of 1) initialization/instatiation of derived class variables 2) invoking of base class constructor in this code snippet public class base { int y = 1; public base() { y = 2; function(); } void function () { System.out.println("In base Value = " + String.valueOf(y)); } public static class derived extends base { int y = 3; public derived() { function(); } void function () { System.out.println("In derived Value = " + String.valueOf(y)); } } public static void main

问题 why the standard decides to do nothing for non-class type members during a default initialization but performs zero initialization during value initialization? Would it be safer if zero initialization is always performed on non-clss type memebers? 回答1: One of the basic principles of design in the language is that you should not pay for something you don't need. If you want your members initialized, you can ask the compiler to do so, but if you don't want that, the cost won't be forced onto

问题 I have a lazy loaded module that I'm trying to add APP_INITIALIZER but its not firing. I have the exact same syntax as my main app where its working as expected. Does a lazy loaded module fire the APP_INITIALIZER? 回答1: No From the docs https://angular.io/api/core/APP_INITIALIZER A function that will be executed when an application is initialized The app is only initialized once, starting with the main module (the one that is bootstrapped) 回答2: Unfortunately APP_INITIALIZER is not called in a

问题 I have this class that has many class members, and a lot of different constructors. Until now, I used a constructor initialization list in each of the constructors that I have, tuning each member the way I wanted. This is quite tedious, because everytime I add a new member to my class, I have to visit each constructor and update the initialization list to add a default value to this member. So, I thought I would add a method to initialize the values I need. Problem ! Since the method is

问题 I have a class and a factory function that creates new anonymous class objects extending that class. However, the anonymous class objects all have a method in which there are references to other objects. In my full program, I need this to create and combine parsers, but I've stripped down the code here. class Base{ public Base run(){ return null; } static Base factory(final Base n){ return new Base(){ public Base run(){ return n; } }; } } public class CircularReferences{ public static void