ios - Object parameter in method postNotification of NSNotificationCenter -


in ios application, posting nsnotification , catching in 1 of uiview in main thread. want pass information along notification. using userinfo dictionary of nsnotification that.

[[nsnotificationcenter defaultcenter] postnotificationname:@"notifyvaluecomputedfromjs" object:self userinfo:@{@"notificationkey":key,@"notificationvalue":value,@"notificationcolor":color,@"notificationtimestamp":time}];

key, value, color , time local variables contains value need pass. in uiview adding observer notification , using notification.userinfo these data

[[nsnotificationcenter defaultcenter] addobserver:self selector:@selector(receivenotification:) name:@"notifyvaluecomputedfromjs" object:nil];  -(void)receivenotification:(nsnotification *)notification {      if ([notification.userinfo valueforkey:@"notificationkey"]!=nil && [[notification.userinfo valueforkey:@"notificationkey"] isequaltostring:self.notificationkey] && [notification.userinfo valueforkey:@"notificationvalue"]!=nil) {          [self updatelabelwithvalue:[notification.userinfo valueforkey:@"notificationvalue"]];      } }

the frequency in notification posted 4 times in 1 second. doing animations in main thread. problem facing here ui lagging. ui respond scroll events or touch events huge delay(i have faced delay of 1 2 seconds). after research came know nsdictionary bulky , cause lag if used in main thread. there other way can pass data through nsnotification?

i have tried out way. have created custom nsobject class save data want , passing object parameter of postnotification method. 

[[nsnotificationcenter defaultcenter] postnotificationname:@"notifyvaluecomputedfromjs" object:customdataobject userinfo:nil];

here customdataobject instance of custom nsobject class. know parameter meant sender of notification(usually self). wrong approach if sending custom object parameter?

as bobdave mentioned, key send notification on thread other main ui thread. can accomplished dispatch_async, or queue.

the typical pattern behavior sender:

-(void)senddatatoobserver {     dispatch_async(dispatch_get_global_queue(dispatch_queue_priority_default, 0), ^{         [[nsnotificationcenter defaultcenter] postnotificationname:@"notifyvaluecomputedfromjs" object:customdataobject userinfo:userinfo:@{@"notificationkey":key,@"notificationvalue":value,@"notificationcolor":color,@"notificationtimestamp":time}];     }); }

and receiver (note: weak self because retain cycles):

-(void)addobserver {     [[nsnotificationcenter defaultcenter] addobserver:self selector:@selector(receivenotification:) name:@"notifyvaluecomputedfromjs" object:nil]; }  -(void)receivenotification:(nsnotification *)notification {      if ([notification.userinfo valueforkey:@"notificationkey"]!=nil && [[notification.userinfo valueforkey:@"notificationkey"] isequaltostring:self.notificationkey] && [notification.userinfo valueforkey:@"notificationvalue"]!=nil) {          __weak typeof (self) weakself = self;           dispatch_async(dispatch_get_main_queue(), ^{              [weakself updatelabelwithvalue:[notification.userinfo valueforkey:@"notificationvalue"]];          });      } }

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