How to view reference count changes in the ARC environment?

How to view reference count changes in the ARC environment?

 

1. Create a new project to test the changes in the reference count.

 

 

 

2. Find the following path: Build Phases ----> Compile Sources ----> AppDelegate. m

 

 

 

3. Select the AppDelegate. m file ,.

 

 

 

 

4. Set Compiler Flags of AppDelegate. m to "-fno-objc-arc "..

This is because we need to write our test code in the AppDelegate. m file. By default, the project manages the memory by ARC. Therefore, we use the parameter "-fno-objc-arc" to set it to manual memory management.

 

 

 

5. Enter the following code in AppDelegate. m:

 

 

- (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;}

 

 

6. Start coding. And run. Output result:

 

21:35:46. 252 Demo of reference count change under ARC [2070: 86317] object-12015-07-14 21:35:46. 252 Demo of reference count change under ARC [2070: 86317] object-22015-07-14 21:35:46. 253 Demo of reference count change under ARC [2070: 86317] object-1

 

 

References:

Advanced iOS development-Tang Qiao.