category chooser

1. Extending the functionality of the classThe category provides a more concise way to extend class than inheritance (inheritance), and we can add methods (excluding data members) to any already existing class without having to access the class's implementation file.The newly added method has the same status as the original method, can access the data members of class, and is fully implanted into class's inheritance system, and the subclass inherits t

More attention should be paid to the standardized installation of category 6 network cable demand At present, although optical fiber has become a buzzword, many related projects are also being implemented. However, due to the technical level, general demand and price factors, it is not possible to form a universal demand product in the market. Currently, copper cables are still the mainstream in network cabling products. The performance of cat5e and

How to determine sales document item Category in sales order Document line item?Make new entries for the appropriate document type and usage indicator for the outcome so you have specified. To assign categories, perform the customizing activity Sales sales document sales Document Item Assign Item Categories 1. Normally, item category group in Sales Org. 2 of material master needs to change,--> Item Cateogr

First, master the use of nsdate and NSDateFormatter nsdate is cocoa? The base class for working with dates and times, encapsulating a givenTime (including date, times, timezone). Learn about the creation of NSDate, how to calculate the current time, the time interval, and the interaction between the time date and the character. 1>. NSDate creation, local time calculation, time interval calculation, time-to-character inter-transferExercise 1: Calculate the time difference between the curre

I know how to make a beautiful category bar picture? new shop, it is necessary to decorate the shop. With iSEE made to eye-catching, personality of the category bar picture, added to the shop home, you can make it easier for buyers to find the baby needs. Let's take a look at iSEE's static category bar effect chart: Dynamic Sidebar Effect Chart:

CategoryA category is a way to add a new method to an existing class.With Objective-c's dynamic run-time allocation mechanism, you can add new methods to existing classes, a way to add new methods to existing classes called Category Catagory, and he can add new methods to any class, including those that do not have source code.Category allows you to do the same without creating subclasses of the object clas

in the real environment, we are most concerned about the ERROR information. If the log level is relatively low, too many log outputs may affect the application performance. Log4j can be initialized in two ways. The first is the Properties file initialization, and the second is the xml file initialization. When the system used the Log4j class for the first time, for example, the getLogger method of the Logger class was used. The source code of log4j of this method is as follows:Static public Log

Android: Intent matches action, category and data principles, androidintent 1. When you define one or more actions in androidmanifest When you use an implicit intent for other activities or services, it is required that the action in your implicit intent must match the action defined in XML. You can only match one XML file. 2. When you define one or more category in androidmanifest Indicates that no

Category in objective-C) 1. Category concept: dynamically add new behaviors (methods) for existing classes) 2. How to Create a category (1) Use xcode to generate a category (2) You can manually generate a category and generate two @ interfaces in the header file. For exa

{Code ...} Your location: item category column Category ID category tree Category name parent category ID parent category path item category management 6 appliances 0 0, modify | copy |

You are here: Product category column Category ID classification tree category name parent class ID parent class path commodity classification management 6 Electric 0 0, modify | Copy | Delete 15 black and white machine 6 0, 6, modify | Copy | Delete 27 Washer 6 0, 6, modify | Copy | Remove 28 LCD TV Machine 6 0, 6, modify | Copy | Remove 3 Ladies 0 0, modify | C

IOS Category does not overwrite the original class method, ioscategory Original Blog, reprinted, please indicate the sourceBlog.csdn.net/hello_hwc Sum up a sentence If you want to override methods of existing classes, consider using inheritance. -------Preface: Category is a method to add methods to an existing class without inheriting or changing the existing class. It is still widely used in IOS d

This class introduces the categories in iOS from three aspects, namely what are categories, the syntax of categories, and the role of categories. The specific contents are as follows:First, Category:Class patches: When you cannot get the source code for an existing class, but you need to supplement the functionality of an existing class, use the category in this case.Categories can only add methods, and cannot add member variables.The use of @property

New shop, it is necessary to decorate the shop. With iSEE made to eye-catching, personality of the category bar picture, added to the shop home, you can make it easier for buyers to find the baby needs. Let's take a look at iSEE's static category bar effect chart: Dynamic Sidebar Effect Chart: To make the category bar picture step: 1.

The file selector in Windows 8 is quite different from the previous versions of Windows, and this article will explain how to use the Windows file selector for single and multiple files, and also to look at the file and folder selectors. Before