arc eye

First, what is ARC? The so-called arc is automatic Reference counting, which is the automatic reference count. ARC was introduced from the iOS5. The arc mechanism was introduced to simplify the memory management of the development process. The arc mechanism is more

that holds a piece of useful data. However, this data is not the only I use in this piece of code, and even many people, in the application of many places. The result is that even if I use this memory, I can't release him, because I'm not sure if someone else needs to use this memory elsewhere. Memory leaks are unavoidable.Memory Management for 1.1.2 OCReference count (Reference count)/retention count (retain count)For a dynamic application of memory, there is a person (pointer) to use, give th

1. Implementation principle: Wheel progressbar (rolling progress bar). In the native Android progress bar, there is only an indeterminate scroll progress bar. Now we can implement a determinate progress bar to display the rolling progress bar of a specific progress, shows the effect:We will explain in three steps: 1. How to draw an arc accurately; 2. How to accurately draw the progress text; 3. How to dynamically simulate the progress process. The thr

Detailed description of the arc () method of canvas and canvasarc MethodWhen drawing a curve for a project, we mainly use the arc () method to draw an arc: context.arc(x,y,r,sAngle,eAngle,counterclockwise);That is, arc (x coordinate of the center, y coordinate of the center, radius of the circle, starting angle (in rad

IOS in ARC environment Dealloc use, understanding misunderstandingThe beautiful Life of the Sun Vulcan (http://blog.csdn.net/opengl_es)This article follows "Attribution-non-commercial use-consistent" authoring public agreementReprint Please keep this sentence: Sun Vulcan's Beautiful Life-this blog focuses on Agile development and mobile and IoT device research: IOS, Android, HTML5, Arduino, Pcduino , Otherwise, the article from this blog refused to

1. PrefaceNext: ios-How to convert a non-ARC project into an arc project (actual combat)2. Memory-management-related configurationWhen we manage the non-arc memory management, we find that when doing some operations memory is still slowly increased such as the simplest random number uitableview display and sliding, memory management, should not appear memory incr

iOS5.0 can start with arc (Automatic Reference counting: Auto reference count) instead of the previous MRC (Manual Reference Counting: Manual reference count). Using arc will reduce the amount of code and the frustration of forgetting to release objects. But there are two sides to everything. After using arc, if you want to reuse a previously written use of the M

Xcode5之后创建项目，默认会自动开启ARC自动引用计数机制，但我们在实际应用开发中考虑到种种原因，有时候不得不关闭（开启）整个应用或部分类的ARC。The steps are:Apple LLVM 6.0-language-objective C, objective-c Automatic Reference counting set N, Project-Build settings O To turn off the entire arc, set Yes to on.Sometimes when we introduce a third-party class library, because the third-party class library does not support

Brother B, neither now strong brother to Hello. So now this weak d Big Brother pointed to the object is a fart, both nil.the difference between strong and weakstrong indicates that the memory area on the heap it points to is no longer pointing to this area. That is to say, I have a strong point to a region, we no longer point to its condition only we point to nil or I am not in memory, no one strong point to me, weak said if no one points to it, it will be cleared memory, and is pointed to nil,

1. Block declarations and thread safetyThe declaration of the block attribute first needs to use the copy modifier, because only the copy block will be in the heap, the life cycle of the block in the stack is bound to the stack, you can refer to the previous article (IOS: Non-arc back block).Another issue to be aware of is thread safety, which needs to be confirmed when declaring the Block property "is it possible for another thread to modify block wh