Question

iOS什么时候使用全局变量 self

Answer 1

ios 单例全局变量写法

interface MySingleton : NSObject
{
⇒① NSString *testGlobal;
}

+ (MySingleton *)sharedSingleton;
⇒②@property (nonxxxx,retain) NSString *testGlobal;

@end

@implementation MySingleton
⇒③@synthesize testGlobal;

+ (MySingleton *)sharedSingleton
{
static MySingleton *sharedSingleton;

@synchronized(self)
{
if (!sharedSingleton)
sharedSingleton = [[MySingleton alloc] init];

return sharedSingleton;
}
}