properties

When should I use @synthesize explicitly?

由 …衆ロ難τιáo~ 提交于 2020-01-18 11:08:45
问题 As far as I know, since XCode 4.4 the @synthesize will auto-generate the property accessors. But just now I have read a sample of code about NSUndoManager , and in the code it noticed that the @synthesize is added explicitly. Like: @interface RootViewController () @property (nonatomic, strong) NSDateFormatter *dateFormatter; @property (nonatomic, strong) NSUndoManager *undoManager; @end @implementation RootViewController //Must explicitly synthesize this @synthesize undoManager; I am feeling

Objective C - Synthesize property [duplicate]

由 吃可爱长大的小学妹 提交于 2020-01-18 05:46:09
问题 This question already has answers here : Closed 7 years ago . Possible Duplicate: Prefixing property names with an underscore in Objective C When synthesizing properties I found out that someone is doing: @synthesize myVar = _myVar; what is "_myVar" and which is the difference with simply doing : @synthesize myVar; Lastly when I should prefer the first solution to the last one? Thanks Luca 回答1: What _myVar really is in your example, is the name of the ivar that is backing your property. By

How to enumerate an object's properties in Python?

由 梦想与她 提交于 2020-01-18 05:16:04
问题 I C# we do it through reflection. In Javascript it is simple as: for(var propertyName in objectName) var currentPropertyValue = objectName[propertyName]; How to do it in Python? 回答1: for property, value in vars(theObject).iteritems(): print property, ": ", value Be aware that in some rare cases there's a __slots__ property, such classes often have no __dict__ . 回答2: See inspect.getmembers(object[, predicate]). Return all the members of an object in a list of (name, value) pairs sorted by name

How do you handle shared members when dealing with interfaces?

由 不问归期 提交于 2020-01-17 05:03:49
问题 So I did tons and tons of work trying to make an interface for a common set of classes. The idea was to make an interface that each class could use within the set, but ultimately each class is different. Turns out interfaces do not like shared members. What I tried: Public Interface ISomeInterface Shared Property Meta() as Object End Interface Public Class A Implements ISomeInterface Shared Public Property Meta() as Object Implements ISomeInterFace.Meta 'Set/get methods End Propery Public

Spring使用SpEL表达式读取properties配置文件的两种方式

由 百般思念 提交于 2020-01-17 04:47:14
第一种： config.properties： index.version=v1 spring配置文件，加载config.properties： <!-- 获取properties中的值 --> < bean id = " configProperties " class = " org.springframework.beans.factory.config.PropertiesFactoryBean " > < property name = " locations " > < list > < value > classpath:config.properties </ value > </ list > </ property > </ bean > <!-- Spring的动态变量,能在bean中直接调用 --> < bean id = " propertyPlaceholderConfigurer " class = " org.springframework.beans.factory.config.PropertyPlaceholderConfigurer " > < property name = " properties " ref = " configProperties " /> </ bean > 注入使用： @Value ( "#

属性配置细节

由 浪尽此生 提交于 2020-01-16 19:57:10
1.【属性值注入还可以用value节点进行注入】 2.【字面值】 （1）字面值：可用字符串表示的值，可以通过<value>元素标签或value属性进行注入。 （2）基本数据类型及其封装类、String等类型都可以采取字面值注入的方式。 （3）若 字面值中包含特殊字符，可以使用<![CDATA[]]>把字符值包裹起来 。 举栗子： 运行结果： 【3.引用其他的bean】 （1）组成应用程序的Bean经常需要相互协作以完成应用程序的功能。要使Bean能够相互访问，就必须在Bean配置文件中指定对Bean的引用。 （2）在Bean的配置文件中，可以通过<ref>元素或者ref属性为Bean的属性或者构造器参数指定对Bean的引用。 <ref>元素： ref属性： （3）也可以在属性或构造器里包含Bean的声明，这样的Bean称为内部Bean。 当Bean实例仅仅给一个特定的属性使用时，可以将其声明为内部Bean。内部Bean声明直接包含在<property>或<constructor-arg>元素里，不需要设置任何id或name属性。 内部Bean不能使用在任何地方。 1 <!-- 内部bean ,不能被外部引用，只能在内部使用--> 2 <property name="car"> 3 <bean class="com.hk.beans.Car"> 4 <constructor-arg

change a property in another viewcontroller

由 半城伤御伤魂 提交于 2020-01-16 15:36:54
问题 I've searched how to run a method from another ViewController on stackoverflow and didn't find an answer. I have a ViewController1 playing an audio using AVAudioPlayer and I want my ViewController2 to be able to change it's volume. I've tried the basic: calling a method in ViewController2 that changes the volume in ViewController1 . This doesn't work. The method is able do output Logs but isn't able to change properties. Thanks 回答1: You need to pass a message from ViewController2 to

修改struts的访问后缀

由 我的梦境 提交于 2020-01-16 14:27:00
第一种方式： 在struts.xml的配置文件中添加 <constant name="struts.action.extension" value="do"></constant> name是从default.properties中找到的 这里面的action,,代表输入的访问路径后缀可以是.action也可以什么都不加，两个逗号就代表了什么都不加 如上面在struts.xml中修改了这个常量的值为do，那么访问的时候就可以在访问名后面加上一个 .do 由于配置文件的加载顺序，是先default.properties后再有struts.xml，所以在struts.xml中的常量配置会把default.properties中的常量配置覆盖掉 第二种方式 在src下创建struts.properties 添加struts.action.extension=htm 注： 如果 这样配置会覆盖struts.xml 的 配置 由于struts配置文件的加载顺序中，struts.properties是在struts.xml的后面，所以加载的时候会将struts.xml中的常量配置给覆盖掉 第三种方式 在web.xml中配置 原理是一样的，也是由于配置文件的加载顺序导致的替换 来源： CSDN 作者： 工资不够-代码来凑 链接： https://blog.csdn.net/qq_37388518

FileNotFoundException with properties file

由 徘徊边缘 提交于 2020-01-16 13:14:32
问题 I'm trying to read some props from backupData.properties . It locates in WEB-INF/classes/ . This is how I do: public class Configures { private static final String INPUT_FILE = "WEB-INF//classes//backupData.properties"; public static String getMail() { Properties prop = new Properties(); try { //load a properties file prop.load(new FileInputStream(INPUT_FILE)); //get the property value return prop.getProperty("mail"); } catch (IOException ex) { ex.printStackTrace(); } return null; } } What

Update .properties file with values from .xml file - problems

由 依然范特西╮ 提交于 2020-01-16 13:02:49
问题 Following Update .properties file with values from .xml file I have the following problems: Problem 1 : Example: X.xml: <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE DOC SYSTEM "ts.dtd"> <?xml-stylesheet type="text/css" href="ts.css"?> <DOC> <PTXT ID="a.b.c.d" CONTEXT="label"><NTI>Text</NTI></PTXT> </DOC> Y.properties: a.b.c.d=Text and my output is: a.b.c.d= Text= = Can you please help me as I really don't understand what's going on. Problem 2 : Example: X.xml my.id = \u00D6ffnen Express
订阅 properties