I am trying to do following task
[[NSUserDefaults standardUserDefaults] setObject:#"Dry" forKey:#"vesselType_preference"];
[[NSUserDefaults standardUserDefaults] synchronize];
where my "vesselType_preference" is multivalue attribute, but it is not getting effected. Please help this is working for other type of attribute but not working for multivalue type.
Thanks
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
if (![defaults objectForKey:#"vesselType_preference"])
{
[defaults setObject:#"Dry" forKey:#"vesselType_preference"];
}
[[NSUserDefaults standardUserDefaults] synchronize];
This should work.
NSUserDefaults can only handle objects of NSDictionary, NSData, NSArray, NSString and BOOL. (There might be another in there, not sure) If you need to store a multiple value object like an array or dictionary, I would store your settings there first, then save that to the defaults.
Your code looks fine for storing information to the user defaults. Just make sure you have your object type specified before saving. (id) will not work... or won't work properly.
Related
Im making an app that takes two strings and an int. I want these to be displayed on another view.
I have put them into an array and Im trying to store them in the NSUserDefaults. I have managed to get this data stored. The problem that im having is that when I change the data and save it again The function that gets the array is called before the one that sets it . So the application always displays the previous data.
I thought It would be easy to fix by changing when the functions are called.
but from the code it looks to me lie they are in the right order.
2012-09-26 13:55:02.764 BeerDivider[4377:907] array returnd = (
2,
"Person 1",
"Person 2"
)
2012-09-26 13:55:02.773 BeerDivider[4377:907] array saved = (
5,
"Person 1",
"Person 2"
)
I can see from logging the array that they are called in the wrong order.
Please can anyone see where im going wrong. This is my first objective-c/xcode post so not sure what code you want to see. I will put in all of it.
http://pastebin.com/BX5gqp17
Sorry if this is a lot of code.
Thanks for the help.
EDIT: update the code
EDIT2: I think what is happening is similar to this iOS do the button's action before prepareSegue
First Take a look on Apple documentation of NSUserDefault
NSUserDefault always return the data which you saved in it
Dont forgot to write [defaults synchronize];
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setObject:yourArray forKey:#"YourKey"]
[defaults synchronize];
According to your given code.
-(void)saveInfo:(NSArray *)myArray
{
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setObject:myArray forKey:#"array"];
[defaults synchronize];
NSLog (#"array saved = %#", [defaults objectForKey:#"array"]);
}
and now check result
Do this:
-(void)saveInfo:(NSArray *)myArray
{
[[NSUserDefaults standardUserDefaults] setObject:myArray forKey:#"array"];
[[NSUserDefaults standardUserDefaults] synchronize]; //u forgot this
NSLog (#"array saved = %#", myArray);
}
I'm storing all my data in NSUserDefaults.
Now I'm trying to store some keys with a specific prefix in an Array. Therefore, I first load the UserDefaults in a Dictionary.
NSString *myPrefix = #"prefix";
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSDictionary *dict = [defaults dictionaryRepresentation];
for (NSString *keyWithPrefix in dict.keyEnumerator) {
if ([keyWithPrefix hasPrefix: myPrefix]) {
[relevantKeys addObject: keyWithPrefix];
}
}
The Problem is: when I print "dict" (which represents UserDefaults). There are some keys missing.
Does NSUserDefaults delete keys, that are not needed temporarily?
Nope it does not, NSUserDefault is a persistance storage,
Please read the following answer it has a very good explanation
How persistent is [NSUserDefaults standardUserDefaults]?
No, but are you calling [NSUserdefaults synchronize] when you are updating them ?
You should probably be using -synchronize method when storing what you want. i,e:
[[NSUserDefaults standardUserDefaults] setValue:someDictionary forKey:#"someKey"];
[[NSUSerDefaults standardUserDefaults] synchronize];
Is this code correct to load and save NSUserDefaults.
// Load
NSDictionary *dict = [[NSUserDefaults standardUserDefaults]
dictionaryRepresentation];
// Save
NSDictionary *dict = ....
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults registerDefaults:dict];
[defaults synchronize]; << Not sure if this is needed
I'm using JSON to hold the dictionary contents and I'm having problems.
I'd just like to know if this code is correct, before I look elsewhere for my problem.
Your Load code will get you a dictionary of all the current default values.
[Note This will probably be much larger than you expect as Mac OS installs a raft of defaults, you might want to make it smaller. For example, you can limit the dictionary to just those defaults in your domain which differ from their registered default using:
NSDictionary *userDefaults = [[NSUserDefaults standardUserDefaults] persistentDomainForName:#"<your bundle identifier>"];
end note]
Your Save code probably doesn't do what you expect, it installs the values you are restoring as the defaults for those keys - so if you support "Restore to Default Settings", or something similar, then these are the values that would result. What you probably want to do it set the current value of the keys, this can be done with a simple loop:
NSDictionary *dict = ....
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
foreach(id key in dict)
[defaults setObject:[dict objectForKey:key] forKey:key];
The above code is only an outline, you may need to take care what preferences you save/restore and in what order - but all that depends on your application.
// Get
NSDictionary *dict = [[NSUserDefaults standardUserDefaults] objectForKey:#"myDictionary"];
// Set
NSDictionary *dict = ...
[[NSUserDefaults standardUserDefaults] setObject:dict forKey:#"myDictionary"];
I have an array in my app delegate.In some other class I am adding few dictionaries in this app delegate array.
There only I set this appdelegate array for a key in NSUserDefaults.Later on when I check NSUserDefaults value for key for which I saved the appdelegate array, always shows zero object.
I am using
[[NSUserDefaults standardUserDefaults] setObject:app.testArray forKey:#"theKey"];
You can try this code. I am very sure that it will work for you.
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setObject:yourArray forKey:#"init_val"];
[defaults synchronize];
For Retrieving Data You Should Use The Following Code :
NSMutableArray *newArray=[[[NSUserDefaults alloc] objectForKey:#"init_val"] mutableCopy];
Hope this helps you.
Try this for retrieving data
NSMutableArray *newArray=[[NSUserDefaults standardUserDefaults] objectForKey:#"init_val"];
Use object for key instead of valueforkey eg: [userdefaults objectForKey:#"init_val"];
I have the following code in my initialization (first time) of my app:
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSString *uid=#"1";
[defaults setObject:uid forKey:#"init_val"];
[defaults synchronize];
Much later in the code (in response to a button press) I check the value using:
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSString *initVal=[defaults objectForKey:#"init_val"];
initVal is always nil. I have checked and init_val is set up exactly the same in my settings bundle as another field that I can set and read from without issue (they are both set up with a single field named "Key".
#mlewis54:
You can try this code. I am very sure that it will work for you.
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSString *uid=#"1";
[defaults setObject:uid forKey:#"init_val"];
[defaults synchronize];
For Retrieving Data You Should Use The Following Code :
NSString *initVal=[[NSUserDefaults standardUserDefaults] valueForKey:#"init_val"];
OR
NSString *initVal=[[NSUserDefaults standardUserDefaults] objectForKey:#"init_val"];
EDIT:
If still it gives nil, then you can use the following code:
NSString *initVal=[NSString stringWithFormat:#"%#",[[NSUserDefaults standardUserDefaults] valueForKey:#"init_val"]];
OR
NSString *initVal=[NSString stringWithFormat:#"%#",[[NSUserDefaults standardUserDefaults] objectForKey:#"init_val"]];
Hope this helps you.
Decelare this at an event on click of button ...
NSUserDefaults *savedData = [NSUserDefaults standardUserDefaults];
[savedData setObject:userEmailTextField.text forKey:#"userid"];
and on load load the data and check the value you have entered is showing or not...
userEmailTextField.text =[[NSUserDefaults standardUserDefaults]objectForKey:#"userid"];
You need to use the line
NSString *initVal = [defaults stringForKey:#"init_val"];
- since it's a String you must use stringForKey. You can similarly use boolForKey to get a boolean value.
There's nothing wrong in your code, i tried to copy it in my project and it worked good,
so your error could be probably when you check initVal...
what's the code you use to see if initVal is nil?
and are you sure that when/where you check initVal, that var/oblect is still visible ?
try to insert this immediately after your reading code:
NSLog(#"____text read in pref: %#", initVal);
it writes this in my console window -> __text read in pref: 1
of course it's an NSString, i hope you keep it in mind it's not an int or a NSNumber when you check it...
luca
It might be that the initialisation isn't happening. Put an NSLog in there to check it's executed.
It works fine for me with the same code:
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSString *uid=#"1";
[defaults setObject:uid forKey:#"init_val"];
[defaults synchronize];
NSUserDefaults *defaultss = [NSUserDefaults standardUserDefaults];
NSString *initVal=[defaultss objectForKey:#"init_val"];
NSLog(#"Value of initVal: %#",initVal);
O/P on console: Value of initVal: 1
So try to do it with the same code with print on console.
Are you sure you properly initialize NSUserDefaults? When I initialize, in my app delegate, I always create the default user defaults by creating a dictionary of the default values then:
[[NSUserDefaults standardUserDefaults] registerDefaults:appDefaults];
Where appDefaults is the dictionary. Then you should be able to access them correctly.