How to find the recently viewed records using objective C - objective-c

Question

Im working on recently viewed functionality, I have to create one model class of History. In history i have FileName,Title,ActivityName. Im using 2 methods to store the filename and title.
History.h
-(BOOL)history:(NSString *)sFile activityName:(NSString *)activityName title:(NSString *)title GID_ID:(NSString *)dataGID_ID;
-(id)getHistoryInstance;
-(BOOL)addNewHistory:(Histrory *)history;
-(NSMutableArray *)recentlyViewedDict;
History.m
+(Histrory *)getSharedInstance{
if (!sharedInstance) {
sharedInstance = [[super allocWithZone:NULL]init];
[sharedInstance recentlyViewedDict];
}
return sharedInstance;
}
-(NSMutableArray *)recentlyViewedDict {
return recentlyViewedDict;
}
-(BOOL)history:(NSString *)sFile activityName:(NSString *)activityName title:(NSString *)title GID_ID:(NSString *)dataGID_ID
{
_sFile = sFile;
_titleName = title ;
_dataGID_ID = dataGID_ID;
_activityName = activityName;
[self performSelector:#selector(addNewHistory:) withObject:self afterDelay:0.1];
return YES;
}
-(id)getHistoryInstance {
NSLog(#"RECENTLY VIEWED DICY %#", recentlyViewedDict);
if ([recentlyViewedDict count] == 0) {
recentlyViewedDict = [[NSMutableArray alloc]init];
}
else {
return recentlyViewedDict;
}
return recentlyViewedDict;
}
-(BOOL)addNewHistory:(Histrory *)his {
BOOL val = false;
recentlyViewedDict = [self getHistoryInstance];
if ([recentlyViewedDict count] != 0) {
for (int i = 0 ; i < [recentlyViewedDict count]; i++) {
Histrory *one = (Histrory *) recentlyViewedDict[i];
if ([his.getData_GIDID isEqualToString:one.getData_GIDID]) {
val = false;
[recentlyViewedDict removeObjectAtIndex:i];
}
}
}
else {
NSString *addData = [NSString stringWithFormat:#"%#,%#,%#,%#",his.getsFile,his.getTitle,his.getAcivityName,his.getData_GIDID];
[recentlyViewedDict addObject:addData];
}
if ([recentlyViewedDict count] > 11) {
[recentlyViewedDict removeObjectAtIndex:0];
}
NSLog(#"Recently Viewed %#", recentlyViewedDict);
return YES;
}
In this every time i have to store only 1 file.I want to store at least 10 records, if 11 record inserting then 1 record will be deleted using below method.
if ([recentlyViewedDict count] > 11) {
[recentlyViewedDict removeObjectAtIndex:0];
}
How can i store each time recent record.
ContactDetails.m
historyObj = [[Histrory alloc]init];
[historyObj history:sFile activityName:activityName title:contactName GID_ID:contactGID_ID];
Im calling this method every time to visit details classes. this method works only one time like, it will store only first record, you are visited second time it is showing nil value. How can store the multiple detail classes to store each record.thanks in advance.