all info is an __NSCFDictionary and I'm trying to get access just to the "ratings" key (the 3rd key). Any idea how I would go about grabbing the data from that field?
thanks for any help
my NSLog output from NSLog(#"allinfo description %#", allInfo.description); is the following
allinfo description __NSCFDictionary
2012-03-14 11:50:28.056 Project[1173:11603] key = results -> obj = (
{
geometry = {
location = {
lat = "37.787565";
lng = "-122.409593";
};
};
icon = "http://maps.gstatic.com/mapfiles/place_api/icons/bar-71.png";
id = 6ea9093f35b4b0cf5cfa21b7dd40cb28d5aa5c5c;
name = "Ruby Skye";
rating = "3.4";
reference = "CmRfAAAApDkEMtz2k6RQTmdeamVqY3KrXhpyzLoHc7EUDMCCUi3qD6PsYQE8qO2QjiUohpJIFtub_XUcYqPOt_LSUbILHjMzeHiacXDCSSKhybRB4VTy7-Oi72nibqwI3NmxnoxNEhB1I7mUheViH2V2ESkkmHbwGhS1G-LDz0PfJggIt8sZ2YO_BOILkQ";
types = (
"night_club",
bar,
establishment
);
vicinity = "420 Mason Street, San Francisco";
},
{
geometry = {
location = {
lat = "37.790237";
lng = "-122.404676";
};
};
icon = "http://maps.gstatic.com/mapfiles/place_api/icons/bar-71.png";
id = bf9fc5861d0ab56a337ded8d8c4b49e62709e3e5;
name = "The Irish Bank";
rating = "3.7";
reference = "CnRlAAAAs0ggA4T1ri7H68CE7N1IWhfmY6EcED9pMNhvKhrFRUBFJLw73URrqoBpyGB585u7xDwtbmBV53eBj3rXpMlFI52OKz2Uv5-mIKT5pjFXCZJoTiux_SPoWQWFPCYoePyxhl6NFvmLWr-K-Jr7UnapWRIQNSuYGOFKgYg3yHTtoGq1KxoUqT4O-yIncvKbDJz8IygsdL7P2Go";
types = (
bar,
restaurant,
food,
establishment
);
vicinity = "10 Mark Lane, San Francisco";
},
You have a partial console snippet that looks like an NSArray; but it appears to be an NSDictionary when you log [allInfo class].
Can you try this:
[allInfo enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL *stop) {
NSLog(#"key = %# -> obj = %#",key,obj);
}];
This should log the keys and objects and help elucidate the structure of the NSDictionary you are working with.
Update after OP added log output:
// This should log all of the ratings
NSArray *results = [allInfo objectForKey:#"results"];
[results enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
NSString *ratingStr = [obj objectForKey:#"rating"];
NSLog(#"rating = %#",ratingStr);
}];
The output (allinfo.description) looks like an NSArray with NSDictionaries inside of it but, [allinfo class] says it's an NSDictionary however there doesn't appear to be keys for each element. Apple's documentation specifies this about the keys when calling -description:
If each key in the dictionary is an NSString object, the entries are listed in ascending order by key, otherwise the order in which the entries are listed is undefined.
I'd try using the -allKeys to get an NSArray of all the keys. If they aren't NSStrings then you'll need to figure out what it is in order to access the elements in this dictionary.
The log outPut you posted is an Array.You can access the "rating" by
NSString *ratingValue = [[allInfo.description objectAtIndex:0]objectForKey:#"rating"];
Related
I have successfully downloaded and parsed (I think) the JSON data
NSURL *quoteURL = [NSURL URLWithString:#"http://www.qwoatzz.com"];
NSData *jsonData = [NSData dataWithContentsOfURL:quoteURL];
NSError *error = nil;
NSDictionary *dataDictionary = [NSJSONSerialization JSONObjectWithData:jsonData options:0 error:&error];
However, I'm not too sure how to actually use the JSON data. If the JSON file has an array with two keys, how do I get a value from one of these keys at a specific index (the first one for example) and use that to change the text of a label (I know how to do that, it's just the JSON part I am stuck on)?
2014-10-20 19:46:10.616 Qwoatz-2[3147:454481] dataDictionary : {
count = 10;
"count_total" = 1871;
pages = 188;
posts = (
{
author = "Jason Seifer";
date = "2014-10-20 13:54:11";
id = 24317;
thumbnail = "http://blog.teamtreehouse.com/wp-content/uploads/2014/10/1634685862_92b26b9167_o-150x150.jpg";
title = "What Employers Are Looking For in a Junior Rails Developer";
url = "http://blog.teamtreehouse.com/employers-looking-junior-rails-developer";
},
{
author = "Zac Gordon";
date = "2014-10-16 09:27:38";
id = 24296;
thumbnail = "http://blog.teamtreehouse.com/wp-content/uploads/2014/10/brochure-site-150x150.png";
title = "When is WordPress.com the Right Solution?";
url = "http://blog.teamtreehouse.com/wordpress-com-right-solution-website";
},
{
author = "Gill Carson";
date = "2014-10-15 12:52:43";
id = 24287;
thumbnail = "http://blog.teamtreehouse.com/wp-content/uploads/2014/10/Tahoe_team-Photo-150x150.jpg";
title = "We Are Family – The Whole Team!";
url = "http://blog.teamtreehouse.com/family";
},
{
author = "Jason Seifer";
date = "2014-10-14 15:26:11";
id = 24292;
thumbnail = "http://blog.teamtreehouse.com/wp-content/uploads/2014/10/Chartist-Simple-responsive-charts-2014-10-14-15-24-43-150x150.jpg";
title = "Responsive Charts";
url = "http://blog.teamtreehouse.com/responsive-charts";
},
{
author = "Guil Hernandez";
date = "2014-10-13 09:28:05";
id = 24228;
thumbnail = "http://blog.teamtreehouse.com/wp-content/uploads/2014/09/blend-mode-mult-150x150.jpg";
title = "Cutting-Edge CSS Features You Can Use Today";
url = "http://blog.teamtreehouse.com/cutting-edge-css-features-can-use-today";
},
{
author = "Faye Bridge";
date = "2014-10-10 09:00:45";
id = 24230;
thumbnail = "http://blog.teamtreehouse.com/wp-content/uploads/2014/09/Nick-Bryan-150x150.jpg";
title = "After Just 6 Months Learning Nick is a full-time Web Developer";
url = "http://blog.teamtreehouse.com/6-months-nick-now-full-time-web-developer-major-computing-firm";
},
{
author = "Pasan Premaratne";
date = "2014-10-09 13:59:23";
id = 24250;
thumbnail = "http://blog.teamtreehouse.com/wp-content/uploads/2014/10/Screen-Shot-2014-10-06-at-5.57.16-PM-150x150.png";
title = "Making a Network Request in Swift";
url = "http://blog.teamtreehouse.com/making-network-request-swift";
},
{
author = "Zac Gordon";
date = "2014-10-09 09:21:29";
id = 24278;
thumbnail = "http://blog.teamtreehouse.com/wp-content/uploads/2014/10/wordpress_themes-150x150.jpg";
title = "New Course: WordPress Theme Development";
url = "http://blog.teamtreehouse.com/new-course-wordpress-theme-development";
},
{
author = "Dave McFarland";
date = "2014-10-08 13:47:55";
id = 24255;
thumbnail = "http://blog.teamtreehouse.com/wp-content/uploads/2014/10/Screen-Shot-2014-10-06-at-1.02.40-PM-150x150.png";
title = "How to Install Node.js and NPM on a Mac";
url = "http://blog.teamtreehouse.com/install-node-js-npm-mac";
},
{
author = "Jason Seifer";
date = "2014-10-07 16:15:00";
id = 24273;
thumbnail = "http://blog.teamtreehouse.com/wp-content/uploads/2014/10/html5-device-mockups-150x150.jpg";
title = "Device Mockups";
url = "http://blog.teamtreehouse.com/device-mockups";
}
);
status = ok;
}
An example JSON file that was parsed.
Loop through the dictionary:
for(NSString *key in dataDictionary) {
id myObject = [dataDictionary objectForKey:key];
//do something with myObject
}
An NSDictionary is not an ordered collection, so there is no guarantee that looping through a dictionary as shown above will always loop through the keys in the same order. Apple doesn't provide an ordered dictionary with Cocoa/Cocoa Touch, and generally it is a bad idea to subclass NSDictionary or NSMutableDictionary as they are part of a class cluster.
Looking at the text from your example, posts is actually an array full of dictionaries. Assuming all the keys in your example are constant across the JSON files that you will be fetching, you could retrieve it using
NSArray *posts = [dataDictionary arrayForKey:#"posts"];
This array already appears to be ordered by date. You could then get the title for each post
for(int i = 0; i < [posts count]; i++) {
NSString *title = [((NSDictionary *)(posts[i])) objectForKey:#"title"];
//do something with title
}
1) Do you know the data is an array?
the JSON file has an array with two keys,...
value from one of these keys at a specific index...
This is somewhat of a mixed metaphor for me. When I have a JSON Array or NSArray, I tend to only think of indices (since that how arrays are ordered), and when I have JSON Objects or NSDictionaries, I tend to think of keys.
So, does the return value look like this:
[ "cat", 1, "a" ]
or does the data look like this:
{
"cat": {
"count": 1,
"tag": "a"
}
}
The first example is an Array with 3 elements; the second is an Object with 1 member that itself has 2 members.
2) If the data is correctly parsed as either an NSArray, or NSDictionary ...
Then you simply need to extract the data you want, with the accessors available on either container.
E.g.
NSArray *a = ...
[a firstObject];
[a objectAtIndex:0]; // same as above
NSDictionary *d = ...
d[#"memberName"];
[d objectForKey:#"memberName"]; // same as above
You'll want to actually save that data, or pass it to be processed, instead of just invoking the accessor.
UPDATE: based on the example data updated in the question.
One method is that you could extract the data both a bit manually, and iteratively.
NSDictionary *dataDictionary = ...
NSInteger count = [[dataDictionary objectForKey:#"count"] integerValue];
NSInteger countTotal = [[dataDictionary objectForKey:#"count_total"] integerValue];
NSInteger pagesCount = [[dataDictionary objectForKey:#"pages"] integerValue];
NSString *status = [dataDictionary objectForKey:#"status"];
NSArray *posts = [dataDictionary objectForKey:#"posts"];
for (NSDictionary *post in posts) {
for (NSString *key in post) {
NSLog(#"%#: %#", key, post[key]);
}
}
When you log dataDictionary, unquoted elements that are clearly strings are strings, elements in quotes are strings, integers and other numbers are likely usable numbers, but they may be strings (depends on return format), the date will be a string (and you can use NSDate and NSDateFormatter to pretty print it), status is just a string; for posts, the '(' and ')' wrap an array, and '{','}' wrap dictionaries.
UPDATE 2:
If you really want to do advanced searching, you can use NSPredicate to filter NSDictionary's or NSArray's. For example, something like the following would work:
#import <Foundation/Foundation.h>
int main(int argc, char *argv[]) {
#autoreleasepool {
NSDictionary *data = #{
#"stuff": #1,
#"posts": #[
#{ #"id": #1, #"title": #"one" },
#{ #"id": #2, #"title": #"two" },
#{ #"id": #3, #"title": #"three" },
#{ #"id": #4, #"title": #"four" },
#{ #"id": #5, #"title": #"five" },
]
};
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"SELF.id == %#", #4];
NSString *title = [[data[#"posts"] filteredArrayUsingPredicate:predicate] firstObject];
NSLog(#"title: %#", title);
}
}
prints
title: {
id = 4;
title = four;
}
You can use JSONModel Framework
JSONModel is a data model framework for iOS and OSX. It's written in Objective-C and helps you in several different ways.
You can read more about its key features below:
Rapidly write model code
Validation of the model's input
Atomic data
Type casting between JSON and Obj-C
Built-in data transformers
Custom data transformers
Model cascading
Convert back & forth from/to JSON
Persist model state in memory or file
Create models straight from the Internet
Automatic model compare methods
Note Please make sure your properties name match with key name in JSON
JSONModel Framework
GitHub Link
This example is contrived, but it shows my point.
So, if I have an object graph like the following:
{
sex = male;
uid = 637650940;
work = ({
employer = {
id = 116420715044499;
name = "Software Engineer";
};
"end_date" = "0000-00";
"start_date" = "0000-00";
}, {
employer = {
id = 188733137832278;
name = "Apple";
};
});
},
//Some more objects
(This is an NSArray containing NSDictionarys that have an object of type NSArray).
The key field is work. I want a Key Path that will take the first object in the work array.
If I do this:
NSArray* work = [outerArrayObject objectForKey: #"work"];
id name = [work valueForKeyPath: #"employer.name"];
I get an array containing each name (In the above case, Software Engineer & Apple). Is there a collection operator or something to return the first object? Bonus points if you can develop a Key Path to sort each work by start_date also :)
#PauldeLange - Your answer and links were helpful.
The following simpler version works too (at least as of Xcode 6)
id name = [work valueForKeyPath: #"employer.name.#firstObject”];
In the above 'firstObject' refers to the predefined method on NSArray. If the second object is needed, you can define the following:
#implementation NSArray (CustomKVOOperators)
- (id) secondObject {
return [self count] >=2 ? self[1] : nil;
}
#end
And use:
id name = [work valueForKeyPath: #"employer.name.#secondObject”];
Well to answer my own question, one way to do it is this:
1) Define the following category
#implementation NSArray (CustomKVOOperators)
- (id) _firstForKeyPath: (NSString*) keyPath {
NSArray* array = [self valueForKeyPath: keyPath];
if( [array respondsToSelector: #selector(objectAtIndex:)] &&
[array respondsToSelector: #selector(count)]) {
if( [array count] )
return [array objectAtIndex: 0];
else
return nil;
}
else {
return nil;
}
}
#end
2) Use this KeyPath syntax
NSArray* work = [outerArrayObject objectForKey: #"work"];
id name = [work valueForKeyPath: #"#first.employer.name"];
Thanks to this clever person.
Sorry to perhaps ask stupid questions, but I'm still having issues with Objective-C syntax.
So, I've got this SOAP response from my sudzc.com generated code. It should contain a SQL SELECT result with veh_id and version as columns.
What I get as a response object is a NSMutableArray,
NSMutableArray* soapArray = (NSMutableArray*)value;
so I walk through it:
unsigned count = [soapArray count];
while (count--) {
id myobj = [soapArray objectAtIndex:count];
NSLog(#"myobj: %#", myobj);
}
What I get as a printout is something like:
myobj: {
item = {
key = version;
value = 1;
};
for each row of the SQL result. If this is a printout of the array element, why is there only the version column and not also the veh_id column?
How do I access the value for the key on the object myobj of type id? Do I have to cast it first?
That's the XML String returned from the Zend Soap-Server:
<?xml version="1.0" encoding="UTF-8"?><SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:ns1="http://www.[myurl].com/soap" xmlns:ns2="http://xml.apache.org/xml-soap" xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"><SOAP-ENV:Body><ns1:getActiveVehiclesResponse><return SOAP-ENC:arrayType="ns2:Map[23]" xsi:type="SOAP-ENC:Array"><item xsi:type="ns2:Map"><item><key xsi:type="xsd:string">veh_id</key><value xsi:type="xsd:string">1</value></item><item><key xsi:type="xsd:string">version</key><value xsi:type="xsd:string">1</value></item></item><item xsi:type="ns2:Map"><item><key xsi:type="xsd:string">veh_id</key><value xsi:type="xsd:string">3</value></item><item><key xsi:type="xsd:string">version</key><value xsi:type="xsd:string">1</value></item></item><item xsi:type="ns2:Map"><item><key xsi:type="xsd:string">veh_id</key><value xsi:type="xsd:string">4</value></item><item><key xsi:type="xsd:string">version</key><value xsi:type="xsd:string">1</value></item></item></return></ns1:getActiveVehiclesResponse></SOAP-ENV:Body></SOAP-ENV:Envelope>
No.. You don't need to cast it, since it shows all the data fetched, I am facing problem that the handler method value (of id type) returns first element only.
check following code:
...
request = [service myServiceCall:self action:#selector(myHandlerMethod:) param:param1];
...
}
-(void) myHandlerMethod:(id)value{
NSString *xmlString = [[NSString alloc] initWithData:request.receivedData encoding:NSUTF8StringEncoding];
// now if the "value" returned is type as some array of some object,then any arrays don't handle serialization of all the elements of the array it holds. The following code prints just outer tag. (e.g. )
NSLog("%#",xmlString);
}
Finally found the solution!
The problem lies within the deserializeAsDictionary function.
Since my Soap xml string is structured to have each database column as item - key - value - key - value etc, it adds each column under the key "item" and thus the deserializeAsDictionary function overwrites in the line
[d setObject:v forKey:[child name]]
the already added objects. In a first shot, I have added a column iterator and now call the columns "item1, item2,.." (further optimization might be necessary):
// Deserializes the element in a dictionary.
+(id)deserializeAsDictionary:(CXMLNode*)element {
NSLog(#"deserializeAsDictionary = %#, children: %d", element.stringValue, [element childCount]);
if([element childCount] == 1) {
CXMLNode* child = [[element children] objectAtIndex:0];
if([child kind] == CXMLTextKind) {
NSLog(#"child %# added", [child stringValue]);
return [[[element children] objectAtIndex:0] stringValue];
}
}
NSMutableDictionary* d = [NSMutableDictionary dictionary];
NSInteger i = 1;
NSString *objKey;
for(CXMLNode* child in [element children]) {
id v = [Soap deserialize:child];
if(v == nil) {
v = [NSNull null];
} else {
if([[child name] isEqualToString:#"(null)"]) {
objKey = [NSString stringWithFormat:#"%#",[child stringValue]];
} else if([[child name] isEqualToString:#"key"] || [[child name] isEqualToString:#"value"]) {
objKey = [NSString stringWithFormat:#"%#",[child name]];
} else {
objKey = [NSString stringWithFormat:#"%#%d",[child name],i++];
}
}
[d setObject:v forKey:objKey];
NSLog(#"child %# added", objKey);
}
return d;
}
The result array now looks like:
},
{
item1 = {
key = "veh_id";
value = 29;
};
item2 = {
key = version;
value = 1;
};
}
I have a NSMutableArray and a NSArray. Both consist of elements that are NSDictionarys themselves.
A sample structure of both is as follows:
NSMutableArray
[
{
objectId = 4274;
name = orange;
price = 45;
status = approved;
},
{
objectId = 9035;
name = apple;
price = 56;
status = approved;
},
{
objectId = 7336;
name = banana;
price = 48;
status = approved;
}
.
.
.
.
]
and NSAraay is
NSArray
[
{
objectId = 4274;
name = orange;
price = 106;
status = not_approved;
},
{
objectId = 5503;
name = apple;
price = 56;
status = approved;
}
]
What I want is to merge these two arrays so that, if any element in NSArray has same objectId as any element in NSMutableArray, element in NSArray should overwrite on element in NSMutableArray.
So in this case final merged array should look like this
MergedArray
[
{
objectId = 4274;
name = orange;
price = 106;
status = not_approved;
},
{
objectId = 9035;
name = apple;
price = 56;
status = approved;
},
{
objectId = 7336;
name = banana;
price = 48;
status = approved;
},
{
objectId = 5503;
name = apple;
price = 56;
status = approved;
}
.
.
.
.
]
Only way to this I know is to iterate through both arrays and merge. Is there any better way? Any help will be greatly appreciated.
EDIT:
Following dasblinkenlights suggestion, I did it following way
-(NSMutableArray*)mergeTwoArray:(NSArray*)array1 :(NSArray*)array2
{
//array1 will overwrite on array2
NSSet* parentSet = [NSSet setWithArray:array2];
NSMutableDictionary *dict = [NSMutableDictionary dictionary];
for (NSDictionary *item in parentSet)
[dict setObject: item forKey: [item objectForKey:#"objectId"]];
NSLog(#"initial dictionary is %#",dict);
for (NSDictionary *item in array1)
[dict setObject: item forKey: [item objectForKey:#"objectId"]];
NSLog(#"final dictionary is %# with all values %#", dict,[dict allValues]);
return [NSMutableArray arrayWithArray:[dict allValues]];
}
Since your objectId value can be used as a unique key, you could potentially create an NSMutableDictionary on the side, populate it with NSDictionary objects from the first array using objectId value as the key, go through the second array, do the overwrites, and finally harvest the values of the resultant NSMutableDictionary into your final output.
Note that this approach might be helpful only if your arrays are relatively long (1000+ items). If you deal with 10..100 items, I wouldn't bother, and code two nested loops as you suggested.
I would recommend iterating through both arrays and merging, but first sort them. Once sorted, you can merge two arrays in O(N) time. For most purposes, this is about as fast as you can get, and it requires very little code.
If they are large enough that the sort is a bottleneck, you could get fancy using an NSSet: put the (elements of the) over-riding array in the set first, and then add the elements of the original array. But you would have to implement an isEqual method for your elements. In this case, it would mean that your elements would no longer be NSDictionary, but rather a class that inherits from NSDictionary but implements the isEqual method to compare the object ID fields.
Because NSSet gives amortized constant time access, this would be faster, if the arrays are large, since there is no sort phase.
I am currently trying to work with json and objective-c however having a bit of difficulty. The following is the json that is being returned
{
sethostname = (
{
msgs = "Updating Apache configuration\nUpdating cPanel license...Done. Update succeeded.\nBuilding global cache for cpanel...Done";
status = 1;
statusmsg = "Hostname Changed to: a.host.name.com";
warns = (
);
});
}
I am able to check that the response is coming back and the key is sethostname however no matter what I try I cannot get for example the value of status or statusmsg. Can anyone point me in the right location. The following is basic code I am using to check that sethostname is returned.
NSError *myError = nil;
NSDictionary *res = [NSJSONSerialization JSONObjectWithData:response options:NSJSONReadingMutableLeaves error:&myError];
NSLog([res description]);
NSArray *arr;
arr = [res allKeys];
if ([arr containsObject:#"sethostname"])
{
NSLog(#"worked");
}
When in doubt, write down the structure of your JSON data. For example:
{
sethostname = (
{
msgs = "Updating Apache configuration\nUpdating cPanel license...Done. Update succeeded.\nBuilding global cache for cpanel...Done";
status = 1;
statusmsg = "Hostname Changed to: a.host.name.com";
warns = (
);
});
}
(which is in NeXTSTEP property list format, actually) means that you have a top-level dictionary. This top-level dictionary contains a key called sethostname whose value is an array. This array is comprised of dictionaries, each dictionary having a set of keys: msgs, status, statusmsg, warns. msgs has a string value, status has a number value, statusmsg has a string value,warns` has an array value:
dictionary (top-level)
sethostname (array of dictionaries)
dictionary (array element)
msgs (string)
status (number)
statusmsg (string)
warns (array)
??? (array element)
Having understood this structure, your code should look like:
NSError *myError = nil;
NSDictionary *res = [NSJSONSerialization JSONObjectWithData:response options:NSJSONReadingMutableLeaves error:&myError];
if (!res) { // JSON parser failed }
// dictionary (top-level)
if (![res isKindOfClass:[NSDictionary class]]) {
// JSON parser hasn't returned a dictionary
}
// sethostname (array of dictionaries)
NSArray *setHostNames = [res objectForKey:#"sethostname"];
// dictionary (array element)
for (NSDictionary *setHostName in setHostNames) {
// status (number)
NSNumber *status = [setHostName objectForKey:#"status"];
// statusmsg (string)
NSString *statusmsg = [setHostName objectForKey:#"statusmsg"];
…
}
Why not use the simplest JSON method - [myString jsonValue];
It's part of this JSON framework for objective-c
I don't think if ([arr containsObject:#"sethostname"]) is going to work, because the results array is not going to contain that exact object. It might contain an object with the same content, but it won't be the SAME object.
As jtbandes wrote, you need to log the actually output. NSLog both res and arr and see what you have.