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[控件]NotificationManager提示通知

由 ⅰ亾dé卋堺 提交于 2020-12-13 00:29:25
在main2中直接finish不做操作 package a.b; import android.app.Activity; import android.app.Notification; import android.app.NotificationManager; import android.app.PendingIntent; import android.content.Context; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; public class main extends Activity implements OnClickListener { Button btn1, btn2, btn3; NotificationManager myManager; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main

.NET types in PowerShell classes

由 ≡放荡痞女 提交于 2020-12-12 06:22:26
问题 I am trying to get my head around PowerShell Class best practices, and running into some confusion with a simple class to handle Balloon Tips. Add-Type -assemblyName:System.Drawing Add-Type -assemblyName:System.Windows.Forms class PxMessage { static [PxMessage] $instance static $balloon static $defaultIcon static [PxMessage] GetInstance($processIcon) { if ([PxMessage]::instance -eq $null) { [PxMessage]::instance = [PxMessage]::new() #[PxMessage]::balloon = [Windows.Forms.NotifyIcon]::new()

“Undefined reference” to declared C++ static member variable [duplicate]

由 青春壹個敷衍的年華 提交于 2020-12-12 06:17:12
问题 This question already has answers here : Undefined reference to static class member (7 answers) Closed 4 years ago . I have started programming with Java, I just achieved which I consider as a "good" level in matter of language knowledge. For fun I decided to start programming using C++, I'm fairly new to this language but I'm a fast learner and I think it's not that far from Java. I've created a test class which has a value and a name as attributes, and an objects counter as a global

java的锁机制

由 本小妞迷上赌 提交于 2020-12-08 08:32:40
一段synchronized的代码被一个线程执行之前，他要先拿到执行这段代码的 权限，在java里边就是拿到某个同步对象的锁（一个对象只有一把锁）； 如果这个时候同步对象的锁被其他线程拿走了，他（这个线程）就只能等了（线程阻 塞在锁池等待队列中）。 取到锁后，他就开始执行同步代码(被synchronized修饰的代码）；线程执行完同步代码后马上就把锁还给同步对象，其他 在锁池中等待的某个线程就可以拿到锁执行同步代码了。这样就保证了同步代码在统一时刻只有一个线程在执行。 众所周知，在Java多线程编程中，一个非常重要的方面就是线程的同步问题。 关于线程的同步，一般有以下解决方法： 1. 在需要同步的方法的方法签名中加入synchronized关键字。 2. 使用synchronized块对需要进行同步的代码段进行同步。 3. 使用JDK 5中提供的java.util.concurrent.lock包中的Lock对象。 另外，为了解决多个线程对同一变量进行访问时可能发生的安全性问题，我们不仅可以采用同步机制，更可以通过JDK 1.2中加入的ThreadLocal来保证更好的并发性。 本篇中，将详细的讨论Java多线程同步机制，并对ThreadLocal做出探讨。 大致的目录结构如下： 一、线程的先来后到——问题的提出：为什么要有多线程同步？Java多线程同步的机制是什么？ 二

What Java classes/packages are automatically imported? [duplicate]

由 允我心安 提交于 2020-12-08 06:37:27
问题 This question already has answers here : How does Java decide when to import? (9 answers) Closed 1 year ago . class HelloWorld { public static void main(String[] args) { System.out.println("Hello, World!"); } } In the above example we are using the println method without importing the package of it. So I want to know: What are the packages or classes included automatically? 回答1: Everything in java.lang is imported by default - here you are using java.lang.System and java.lang.String 回答2:

c++ implementing friend/inline functions

由 瘦欲@ 提交于 2020-12-08 05:57:08
问题 I can't seem to find the answer to this newbie question. If I have a class // Header file (.h) Class X { public: friend bool operator==(const X&, const X&); inline size_type rows() const; }; etc... when I go to implement the .cpp file of X, should I include the words inline & friend in the function names in the .cpp file. ie, should I implement my file similar to the below // CPP file (.cpp) #include "X.h" friend bool operator==(const X&, const X&) { //implementation goes here //return true

How to change a class attribute inside __init__?

由 百般思念 提交于 2020-12-06 08:11:43
问题 class Ant: count = 0 def __init__(self): if count == 0: self.real = True else: self.real = False count += 1 So basically what I want to achieve is I want only the first instance of this class to have the "real" attribute to be True , and the subsequent attributes to be False . I know right now this is going to give me unboundlocal error for count . How do I make this work? 回答1: Change count To Ant.count As count is a class member (shared between all instances of Ant class) and does not belong

Template class type alias failing substitution in member declaration

由 假如想象 提交于 2020-12-06 04:41:42
问题 Assume you have a templated class like this: template <typename type> class Object { using length_t = unsigned int; template <length_t length> void put(type (&)[length]); }; and you declared a put(...) method in it like so. How do you go about declaring that put(...) method outside the class ? Here's one approach someone might take: /* ERROR: Doesn't match any declarations(?) */ template <typename type> template <typename Object<type>::length_t length> void Object<type>::put(type (&)[length])

Asp.net MVC3 access internal class from razor View

由 浪子不回头ぞ 提交于 2020-12-05 12:25:09
问题 This is not a duplicated question. I've already searched on SO but I need a different thing. Is today a way to access an internal class from Razor View, I know that the assembly must be visible and is it yet. No properties nor methods declared in an "internal" class are accessible from Views by default. I need a way to override this. Thanks. 回答1: In most cases you can change the class from internal to public. You can use the InternalsVisibleTo when that isn't desirable. In the case of

Adding new objects to an ArrayList in constructor

由 懵懂的女人 提交于 2020-11-28 02:54:37
问题 I am trying to add newly created objects to an ArrayList in the constructor of a class. The new objects are being created in another class in the main method. Main method: public static void main(String[] args) { // TODO code application logic here Player p1 = new Player("Peter"); } My Player class: public class Player { protected static int age; protected static String name; protected static ArrayList players = new ArrayList(); Player(String aName) { name = aName; age = 15; players.add(new
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