I am finding some problem while saving and retrieving data using nsuserdefaults.
What i want to do- iam accepting name and number from user from viewcontroller and saving it using nsuserdefault. when i click on save button i want to retrieve all the values from nsuserdefault and display it on tableview. now when i save the new data i want this data to get added to the existing data of nsuserdefault. can anyone help me with saving and retrieving nsuserdefault data.
----------MyCode---------------
nsuserdefaults *objdefault =[nsuserdefaults standarduserdefaults];
nameArray = [objdefault objectforkey:#"Name"];
[newNameArray addobject:txtName.text];
[nameArray addobject:newNameArray];
[objdefault setobject:nameArray forkey:#"Name"];
[objdefault synchronize];
all this saves and accepts null value
Please help. and thank you in advance
Use these methods to add name to NSUserDefaultsand get from NSUserDefaults
To add the name to NSUserDefaults call [self addNameToUserDefaults:#"abc"];
-(void)addNameToUserDefaults:(NSString *)name number:(NSString*)number{
NSUserDefaults *objdefault =[NSUserDefaults standardUserDefaults];
NSMutableArray *nameArray = [[objdefault objectForKey:#"NameAndNumber"] mutableCopy];
if(!nameArray)
nameArray = [#[] mutableCopy];
[nameArray addObject:#{#"name":name,#"number":number}];
[objdefault setObject:nameArray forKey:#"NameAndNumber"];
[objdefault synchronize];
}
To get all names from NSUserDefaults call NSMutableArray *names = [self getAllNames];
-(NSMutableArray *)getAllNames{
NSUserDefaults *objdefault =[NSUserDefaults standardUserDefaults];
return [[objdefault objectForKey:#"NameAndNumber"] mutableCopy];
}
It's not possible to add values for same in NSUSerDefaults. it will show you last value only. You should go for Core data or Sqlite. Still if you are not comfortable with that you can use plist to achieve this functionality.
This is what I have done in my project. You have to use NSMutableDictionary to add more value
- (void)addUserLocation:(NSString *)username location:(NSMutableDictionary *)location
{
NSString *currentUserKey = [NSString stringWithFormat:#"%#_%#", UserDefaultsKeyLocationData, username, nil];
NSMutableArray *oldData = [[NSMutableArray alloc]init];
if ([self loadUserLocation:username] != nil) {
oldData = [self loadUserLocation:username];
}
if (![oldData containsObject:location]) {
[oldData addObject:location];
}
[[NSUserDefaults standardUserDefaults] setObject:oldData forKey:currentUserKey];
[[NSUserDefaults standardUserDefaults] synchronize];
}
- (NSMutableDictionary *)loadUserLocation:(NSString *)username
{
NSString *currentUserKey = [NSString stringWithFormat:#"%#_%#", UserDefaultsKeyLocationData, username, nil];
return [[[NSUserDefaults standardUserDefaults] objectForKey:currentUserKey] mutableCopy];
}
If you want get all data. Please call loadUserLocation in your code
Related
language: Objective-C,
I'm new at iOS development so please guide me in a easiest way if you can, i'm saving data into dictionary then NSUserDefaults after that i want to get the data from they NSUserDefaults, I'm working when user clicked in a texfield then text should be stored into dictionary but when i check into Xcode after setting a break points dictionary shows nil. I'm sending screenshots and code please help me.
Thanks
initialization of dictionary in viewDidLoad
save to NSUserDefaults
-(void)textFieldDidEndEditing:(UITextField *)textField {
//we'll use the following method if the TF is out of the table means not in a cell.
if([textField isEqual:self.getNameLabel]){
[nameDateDict setObject:[textField text] forKey:K_NAME];
[self saveToNSUserDefaults];
}
}
Xcode-output
nameDateDict NSMutableDictionary * nil 0x0000000000000000
Sorry the name of texfield is getNameLabel, I'll edit it later so please don't confuse after reading the name.
Even that i've checked this code is working
[timeDict setObject:#"Hello" forKey:#"Greetings"];
[timeDict setObject:#"Bye" forKey:#"B_Key"];
[timeDict setObject:#"what?" forKey:#"W_Key"];
[[NSUserDefaults standardUserDefaults] setObject:timeDict forKey:#"Greetings"];
[[NSUserDefaults standardUserDefaults] setObject:timeDict forKey:#"B_Key"];
[[NSUserDefaults standardUserDefaults] setObject:timeDict forKey:#"W_Key"];
[[NSUserDefaults standardUserDefaults] synchronize];
timeDict = [[NSUserDefaults standardUserDefaults] objectForKey:#"Greetings"];
timeDict = [[NSUserDefaults standardUserDefaults] objectForKey:#"B_Key"];
timeDict = [[NSUserDefaults standardUserDefaults] objectForKey:#"W_Key"];
A couple of things are going on here. First, you have a scope problem, in that your create a local dictionary object in viewDidLoad, which you can't access later. It looks as though you'll want to have an NSMutableDictionary property available for the class, which should be designated either in the header file or interface extension in the implementation file (depending on your use of this dictionary in your project):
#property (nonatomic, strong) NSMutableDictionary *nameDateDictionary;
Second, you aren't correctly initializing or accessing your dictionary and it's objects. So, (using some literal syntax shortcuts) your viewDidLoad and saveToNSUserDefaults methods:
- (void)viewDidLoad
{
[super viewDidLoad];
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSString *name = [defaults objectForKey:K_NAME];
NSDate *startDate = [defaults objectForKey:K_START_DATE];
NSDate *endDate = [defaults objectForKey:K_END_DATE];
NSMutableDictionary *dict = [[NSMutableDictionary alloc] initWithDictionary:#{K_NAME: name,
K_START_DATE: startDate,
K_END_DATE: endDate}];
self.nameDateDictionary = dict;
}
- (void)saveToNSUserDefaults
{
NSMutableDictionary *dict = self.nameDateDictionary;
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setObject:dict[K_NAME] forKey:K_NAME];
[defaults setObject:dict[K_START_DATE] forKey:K_START_DATE];
[defaults setObject:dict[K_END_DATE] forKey:K_END_DATE];
[defaults synchronize];
}
- (BOOL)textFieldShouldReturn:(UITextField*)theTextField {
[theTextField resignFirstResponder];
return YES;
}
-(void) textFieldDidEndEditing:(UITextField *)textField {
[self saveToNSUserDefaults:#{#"keyName":textField.text}];
}
-(void)saveToNSUserDefaults:(NSDictionary *)dict{
[[NSUserDefaults standardUserDefaults] setObject:dict forKey:#"myDictionary"];
}
-(void *)retrieveFromNSUserDefaults{
NSDictionary *tempDict=[[NSDictionary alloc] initWithDictionary:[[NSUserDefaults standardUserDefaults] objectForKey:#"myDictionary"]];
NSlog(#"TextField Value: %#",[tempDict objectForKey:#"keyName"]);
}
The way you are storing the dictionary was not correct. Please go through the https://developer.apple.com/library/mac/documentation/Cocoa/Reference/Foundation/Classes/NSDictionary_Class/index.html for more about how to use them.
Everyone came from a beginner's stage but try not to skip the basics.
As on your screenshots you are storing dictionary values in a wrong way, you store each time the whole dictionary to each NSUserDefaults key. It schoul be like that:
NSMutableDictionary *dict = [[NSMutableDictionary alloc] init];
[dict setObject:#"value" forKey:#"key"];
[[NSUserDefaults standardUserDefaults] setObject:[dict objectForKey:#"key"] forKey:#"key"];
To get back a value from NSUserDefaults to dictionary:
[dict setObject:[[NSUserDefaults standardUserDefaults] objectForKey:#"key"] forKey:#"key"];
I am try to add a NSMutableArray into the NSUserDefault but it is always retuning null.
I know that .so I'm even creating a mutable copy os array as well but still.
Values returned from NSUserDefaults
are immutable, even if you set a
mutable object as the value. For
example, if you set a mutable string
as the value for "MyStringDefault",
the string you later retrieve using
stringForKey: will be immutable.
NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
NSMutableArray *myStoredEvents=[prefs objectForKey:#"MySavedEvents"];
NSMutableArray *myStoredEventsNew=[[NSMutableArray alloc]init];
myStoredEventsNew=myStoredEvents;
NSMutableArray *tempDic=[myevents objectAtIndex:eventId];//myevents a NSMutableArray
if(myStoredEventsNew != nil)
{
[myStoredEventsNew insertObject:tempDic atIndex:0];
}
else
{
[myStoredEventsNew insertObject:tempDic atIndex:myStoredEvents.count];
}
NSLog(#"New dictonary before modification :%#",tempDic);
[prefs setObject:myStoredEventsNew forKey:#"MySavedEvents"];
[prefs synchronize];
Try this code --
NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
NSLog(#"DEBUG :: %#",[prefs objectForKey:#"MySavedEvents"]);
NSMutableArray *myStoredEvents;
if ([prefs objectForKey:#"MySavedEvents"] == NULL) {
myStoredEvents = [[NSMutableArray alloc]init];
}else{
myStoredEvents=[[prefs objectForKey:#"MySavedEvents"] mutableCopy];
}
NSMutableArray *tempDic=[myevents objectAtIndex:eventId];//myevents a NSMutableArray
[myStoredEvents addObject:tempDic];
NSLog(#"New dictonary before modification :%#",myStoredEvents);
[prefs setObject:myStoredEvents forKey:#"MySavedEvents"];
[prefs synchronize];
May this solve your problem
you can save array in NSuserdefaults like this :-
[[NSUserDefaults standardUserDefaults] setObject:yourArray forKey:#"MySavedEvents"];
[[NSUserDefaults standardUserDefaults] synchronize];
and you can put check condition to check NSuserdefault like this :-
NSObject * object = [prefs objectForKey:#"MySavedEvents"];
if(object != nil){
//object is there
}
You can put further conditions according to your need, this is just a basic structure of how to achieve this.
I normally save the selected indexPath of a UiTableView in NSUserDefaults, this is how I normally do it:
self.lastIndexPathUsed = indexPath.row;
NSUserDefaults *userdefaults = [NSUserDefaults standardUserDefaults];
[userdefaults setObject:[NSString stringWithFormat:#"%ld",(long)indexPath.row] forKey:#"lastIndexPathUsedForSellerType"];
[[NSUserDefaults standardUserDefaults] synchronize];
Then I restore it:
self.lastIndexPathUsed = [[[NSUserDefaults standardUserDefaults] objectForKey:#"lastIndexPathUsedForSellerType"] floatValue];
So self.lastIndexPathUsed is just a float value.
The above works fine on a single select table view. However on a multi-select tableview I can't see to get it working.
While the UITableView is on screen I save all the indexPaths into an array. However saving that array into NSUserDefaults causes a crash due to indexPath not being an object as such.
How to save an array how indexPaths into NSUserDefaults?
Try to archive your array to NSData before saving them to NSUserDefaults:
NSData *indexPathArrayData = [NSKeyedArchiver archivedDataWithRootObject:_indexPathArray];
and after getting the NSData from NSUserDefaults, you can unarchive them :
_indexPathArray = [NSKeyedUnarchiver unarchiveObjectWithData:indexPathArrayData];
You can try this :
[[NSUserDefaults standardUserDefaults] setObject:yourMutableArray forKey:#"Key"];
And then get it like this :
NSMutableArray *array = [NSMutableArray arrayWithArray:[[NSUserDefaults standardUserDefaults] objectForKey:#"Key"]];
Hope it helps.
Im storing a NsMutableArray in Nsuserdefaults, I think this can be done and its correct, so Im adding a text from a TexField to the Array but when I try to read it in a NSLOG sends null, heres the code:
#property(nonatomic, strong)NSMutableArray *tasks;
NSUserDefaults *standardUserDefaults = [NSUserDefaults standardUserDefaults];
[standardUserDefaults setObject:self.tasks forKey:#"tasks"];
[self.tasks addObject:textField.text];
NSLog(#"tasks:%#", [[NSUserDefaults standardUserDefaults]objectForKey:#"tasks"]);
Thanks!!
You need to add the text to the array BEFORE you save it to defaults
NSUserDefaults *standardUserDefaults = [NSUserDefaults standardUserDefaults];
// make sure self.tasks is initialized
if (!self.tasks) self.tasks = [NSMutableArray new];
// add object first
[self.tasks addObject:textField.text];
// now save array
[standardUserDefaults setObject:self.tasks forKey:#"tasks"];
NSLog(#"tasks:%#", [[NSUserDefaults standardUserDefaults]objectForKey:#"tasks"]);
If this is returning null, then
I'm trying to add elements to an NSMutableArray whenever a user selects a country. But each time I use [myarray setobject:#""];, it's adding the new value, overwriting my old value. I want this array as I'm using it in:
[[NSUserDefaults standardUserDefaults]setObject:(NSMutableArray *)selectedCountriesByUser forKey:#"userSelection"];
[[NSUserDefaults standardUserDefaults]synchronize];
I want an array which maintains the list of countries selected by the user even after the application is closed.
What should I do?
setObject replace all objects in array
for example, get value from NSUserDefault:
NSMutableArray *myMutableArray = [NSMutableArray arrayWithArray:[[NSUserDefault standardUserDefault] objectForKey:"userSelection"]];
you should use [myMutableArray addObject:"aCountry"]; without overwriting, but adding only
and after
[[NSUserDefaults standardUserDefaults]setObject:myMutableArray forKey:#"userSelection"];
[[NSUserDefaults standardUserDefaults]synchronize];
EDIT:
-(void) viewDidLoad {
//your selectedCountriesByUser
myMutableArray = [NSMutableArray arrayWithArray:[[NSUserDefault standardUserDefault] objectForKey:"userSelection"]];
}
...
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
//add object to array
[myMutableArray adObject:"yourObj"];
[[NSUserDefaults standardUserDefaults]setObject:myMutableArray forKey:#"userSelection"];
[[NSUserDefaults standardUserDefaults]synchronize];
}
You're asking two different things. First, -setObject: is not a NS(Mutable)Array method. You are probably looking for the -addObject: method. So, to add an object to your NSMutableArray, you need to do:
[myMutableArray addObject:yourObject]
//Remember that `-addObject` is present only in NSMutableArray, not in NSArray
The second thing you are trying to achieve is to store the array in NSUserDefaults. to do so, after you add the object to the array you want, you should be fine do to so:
[[NSUserDefaults standardUserDefaults] setObject:myMutableArray forKey:#"userSelection"];
[[NSUserDefaults standardUserDefaults] synchronize];
// ARRAY DECLARATION AND ASSIGNMENT OF VALUES TO IT
NSMutableArray * selectedCountriesByUserArray=[[NSMutableArray alloc] init];
[selectedCountriesByUserArray addObject:#"value1"];
[selectedCountriesByUserArray addObject:#"value2"];
[selectedCountriesByUserArray addObject:#"value3"];
// STORING AN ARRAY WITH THE KEY "userSelection" USING NSUSERDEFAULTS
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setObject:selectedCountriesByUserArray forKey:#"userSelection"];
[defaults synchronize];