How to view the change of reference count in arc-environment

First, create a new project to test the change in reference count.

Second, find the following path build phases---->compile Sources---->APPDELEGATE.M

Three, select the APPDELEGATE.M file.

Four, set APPDELEGATE.M's compiler flags to "-fno-objc-arc".

This is because we are going to write our test code in the APPDELEGATE.M file. The project, by default, is the arc-managed memory. So, we'll use the parameter "-fno-objc-arc" to set it to manually manage memory.

Five, enter the following code in the APPDELEGATE.M:

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<span style="font-size: 18px;">- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    // Override point for customization after application launch.            NSObject *object=[[NSObject alloc]init];    NSLog(@"object-%ld",[object retainCount]);    NSObject *another=[object retain];    NSLog(@"object-%ld",[object retainCount]);    [another release];    NSLog(@"object-%ld",[object retainCount]);    [object release];      return YES;}</span>

Six, begin to write the code. and run. Output results;

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<span style="font-size: 18px;">2015-07-14 21:35:46.252 ARC下引用计数的变化Demo[2070:86317] object-12015-07-14 21:35:46.252 ARC下引用计数的变化Demo[2070:86317] object-22015-07-14 21:35:46.253 ARC下引用计数的变化Demo[2070:86317] object-1</span>

Resources:

iOS Development advanced-Tang Qi.

How to view the change of reference count in arc-environment