I want to create a model class for the json.
My JSON example is given below
json response from API:
msg = '{"type":"TYPE_NM","payload":{"responseCode":0,"nextCheckTime":30}}';
I want to create a codable(Swift) properties is like in Objective-C.
I have created two nsobject interfaces as "type" and "payload". Below I am giving my class snippets.
//msg model
#interface MessageModel : NSObject
#property (nonatomic) NSString *type;
#property (nonatomic) Payload *payload;
#end
//for payload
#interface Payload : NSObject
#property (nonatomic) NSUInteger responseCode;
#property (nonatomic) NSUInteger nextCheckTime;
#end
You can convert json string to NSDictionary object and use it to create MessageModel
Payload
#interface Payload : NSObject
#property (nonatomic) NSUInteger responseCode;
#property (nonatomic) NSUInteger nextCheckTime;
#end
#implementation Payload
- (instancetype)initWithDictionary:(NSDictionary *)dict {
self = [super init];
if (self) {
_responseCode = [dict[#"responseCode"] integerValue];
_nextCheckTime = [dict[#"nextCheckTime"] integerValue];
}
return self;
}
#end
MessageModel
#interface MessageModel : NSObject
#property (nonatomic) NSString *type;
#property (nonatomic) Payload *payload;
#end
#implementation MessageModel
- (instancetype)initWithDictionary:(NSDictionary *)dict {
self = [super init];
if (self) {
_type = dict[#"type"];
_payload = [[Payload alloc] initWithDictionary:dict[#"payload"]];
}
return self;
}
- (instancetype)initWithJson:(NSString *)json {
self = [super init];
if (self) {
NSData *data = [json dataUsingEncoding:NSUTF8StringEncoding];
NSDictionary *dict = [NSJSONSerialization JSONObjectWithData:data options:0 error:nil];
_type = dict[#"type"];
_payload = [[Payload alloc] initWithDictionary:dict[#"payload"]];
}
return self;
}
#end
Usage
NSString *input = #"{\"type\":\"TYPE_NM\",\"payload\":{\"responseCode\":0,\"nextCheckTime\":30}}";
MessageModel *model = [[MessageModel alloc] initWithJsonString:input];
Related
I am new to Objective C, I'm trying to add objects to NSMutableArray that I can use multiple times on my project. I have a Model class as
History.h
import
#interface History : NSObject
#property (nonatomic) NSString *itemName;
#property (nonatomic) int quantity;
#property (nonatomic) double total;
#property (nonatomic) NSDate *purchaseDate;
- (instancetype)initWithName: (NSString*)itemName withQuantity:(int)quantity withTotal:(double) total withPurchaseDate:(NSDate*) purchaseDate;
#end
History.m
#import "History.h"
#implementation History
-(instancetype)initWithName: (NSString*)iName withQuantity:(int)iQuantity withTotal:(double) iTotal withPurchaseDate:(NSDate*) iPdate {
self = [super init];
if(self) {
self.itemName = iName;
self.quantity = iQuantity;
self.quantity = iQuantity;
self.purchaseDate = iPdate;
}
return self;
}
#end
Repository.h
#import <Foundation/Foundation.h>
#interface Repository : NSObject
#property (nonatomic) NSMutableArray *itemHistory;
-(void) pushToArray:(NSString *)name withQuantity:(int)qty withTotal:(double) total withPurchaseDate:(NSDate*) pDate;
#end
Repository.m
#import "Repository.h"
#import "History.h"
#interface Repository()
//#property (nonatomic) NSMutableArray *itemHistory;
#end
#implementation Repository
-(NSMutableArray *) itemHistory {
if(_itemHistory == nil) {
_itemHistory = [[NSMutableArray alloc] init];
}
return _itemHistory;
}
This is my method that I want to use to add objects to the MutableArray.
-(void) pushToArray:(NSString *)name withQuantity:(int)qty withTotal:(double) total withPurchaseDate:(NSDate*) pDate {
self.itemHistory = [[NSMutableArray alloc] init];
History *obj = [[History alloc] init];
obj.itemName = name;
obj.quantity = qty;
obj.total = total;
obj.purchaseDate = pDate;
[self.itemHistory addObject:obj];
}
#end
Thank you for your help in advance.
Every time you call pushToArray:... you are replacing the existing itemHistory with a new, empty, mutable array. You'll only ever see the last item to be pushed in that array.
However, you also don't need to lazily initialize _itemHistory. Just create an instance in your init method and be done with it. Saves confusion and refactoring hell.
In your Repository class, simply implement the designated initializer:
- (instancetype) init
{
if (self=[super init]) {
_itemHistory = [[NSMutableArray alloc] init];
}
return self;
}
Uncomment the property:
#interface Repository()
#property (nonatomic) NSMutableArray *itemHistory;
#end
And remove this from the -pushToArry:... method:
//self.itemHistory = [[NSMutableArray alloc] init];
If it still doesn't work, you need to show how you are logging the failure.
In my app, I am trying to save the pins that are on the map so that they are there when the user opens the app after it is terminated. I have conformed my mkAnnotation class to NSCoding, and implemented the two required methods. The annotations are all stored in a NSMutableArray in a singleton class, so I am really just trying to save the array in the singleton class. Everything is being encoded fine, but I do not think they are being decoded. Here is some code:
This is my MKAnnotation class:
#import <CoreLocation/CoreLocation.h>
#import <MapKit/MapKit.h>
#interface MapPoint : NSObject <MKAnnotation, NSCoding>
{
}
- (id)initWithAddress:(NSString*)address
coordinate:(CLLocationCoordinate2D)coordinate
title:(NSString *)t;
#property (nonatomic, readwrite) CLLocationCoordinate2D coordinate;
//This is an optional property from MKAnnotataion
#property (nonatomic, copy) NSString *title;
#property (nonatomic, readonly, copy) NSString *subtitle;
#property (nonatomic) BOOL animatesDrop;
#property (nonatomic) BOOL canShowCallout;
#property (copy) NSString *address;
#property (nonatomic, copy) NSString *imageKey;
#property (nonatomic, copy) UIImage *image;
#end
#implementation MapPoint
#synthesize title, subtitle, animatesDrop, canShowCallout, imageKey, image;
#synthesize address = _address, coordinate = _coordinate;
-(id)initWithAddress:(NSString *)address
coordinate:(CLLocationCoordinate2D)coordinate
title:(NSString *)t {
self = [super init];
if (self) {
_address = [address copy];
_coordinate = coordinate;
[self setTitle:t];
NSDate *theDate = [NSDate date];
subtitle = [NSDateFormatter localizedStringFromDate:theDate
dateStyle:NSDateFormatterShortStyle
timeStyle:NSDateFormatterShortStyle];
}
return self;
}
- (void)encodeWithCoder:(NSCoder *)aCoder {
[aCoder encodeObject:_address forKey:#"address"];
NSLog(#"ENCODING coordLatitude %f coordLongitude %f ", _coordinate.latitude, _coordinate.longitude);
[aCoder encodeDouble:_coordinate.longitude forKey:#"coordinate.longitude"];
[aCoder encodeDouble:_coordinate.latitude forKey:#"coordinate.latitude"];
[aCoder encodeObject:title forKey:#"title"];
}
- (id)initWithCoder:(NSCoder *)aDecoder {
self = [super init];
if (self) {
[self setAddress:[aDecoder decodeObjectForKey:#"address"]];
NSLog(#"DECODING coordLatitude %f coordLongitude %f ", _coordinate.latitude, _coordinate.longitude);
_coordinate.longitude = [aDecoder decodeDoubleForKey:#"coordinate.longitude"];
_coordinate.latitude = [aDecoder decodeDoubleForKey:#"coordinate.latitude"];
[self setTitle:[aDecoder decodeObjectForKey:#"title"]];
}
return self;
}
#end
Here is my singleton class:
#import <Foundation/Foundation.h>
#class MapPoint;
#interface Data : NSObject
{
NSMutableArray *_annotations;
}
#property (retain, nonatomic) NSMutableArray *annotations;
+ (Data *)singleton;
- (NSString *)pinArchivePath;
- (BOOL)saveChanges;
#end
#implementation Data
#synthesize annotations = _annotations;
+ (Data *)singleton {
static dispatch_once_t pred;
static Data *shared = nil;
dispatch_once(&pred, ^{
shared = [[Data alloc] init];
shared.annotations = [[NSMutableArray alloc]init];
});
return shared;
}
- (id)init {
self = [super init];
if (self) {
NSString *path = [self pinArchivePath];
_annotations = [NSKeyedUnarchiver unarchiveObjectWithFile:path];
if (!_annotations) {
_annotations = [[NSMutableArray alloc]init];
}
}
return self;
}
- (NSString *)pinArchivePath {
NSArray *cachesDirectories = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);
NSString *cachesDirectory = [cachesDirectories objectAtIndex:0];
return [cachesDirectory stringByAppendingPathComponent:#"pins.archive"];
}
- (BOOL)saveChanges {
NSString *path = [self pinArchivePath];
return [NSKeyedArchiver archiveRootObject:[Data singleton].annotations
toFile:path];
}
#end
In my viewDidLoad method on the map view controller, I try and place the annotations in the singleton array on the map with this:
for (MapPoint *mp in [Data singleton].annotations) {
[_worldView addAnnotation:mp];
}
The main problem is in the singleton method in these lines:
dispatch_once(&pred, ^{
shared = [[Data alloc] init];
shared.annotations = [[NSMutableArray alloc]init]; //<-- problem line
});
The shared = [[Data alloc] init]; line decodes and initializes the annotations array.
Then the shared.annotations = [[NSMutableArray alloc]init]; line re-creates and re-initializes the annotations array thus discarding the just-decoded annotations so the singleton always returns an empty array.
Remove the shared.annotations = [[NSMutableArray alloc]init]; line.
As already mentioned in the comment, the other minor issue, which causes simply confusion, is the placement of the NSLog where the coordinate is being decoded. The NSLog should be after the decode is done.
I am trying to use singleton in my app. I want to share 8 strings using a singleton.
This is the tutorial I referred to -> http://www.galloway.me.uk/tutorials/singleton-classes/
My code:
- MyManager.h
#import <foundation/Foundation.h>
#interface MyManager : NSObject {
NSString *someProperty1;
NSString *someProperty2;
NSString *someProperty3;
NSString *someProperty4;
NSString *someProperty5;
NSString *someProperty6;
NSString *someProperty7;
NSString *someProperty8;
}
#property (nonatomic, retain) NSString *someProperty1;
#property (nonatomic, retain) NSString *someProperty2;
#property (nonatomic, retain) NSString *someProperty3;
#property (nonatomic, retain) NSString *someProperty4;
#property (nonatomic, retain) NSString *someProperty5;
#property (nonatomic, retain) NSString *someProperty6;
#property (nonatomic, retain) NSString *someProperty7;
#property (nonatomic, retain) NSString *someProperty8;
+ (id)sharedManager;
#end
MyManager.m
#import "MyManager.h"
#implementation MyManager
#synthesize someProperty;
#pragma mark Singleton Methods
+ (id)sharedManager {
static MyManager *sharedMyManager = nil;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
sharedMyManager = [[self alloc] init];
});
return sharedMyManager;
}
- (id)init {
if (self = [super init]) {
someProperty1 = [[NSString alloc] initWithString:#"Default Property Value"];
someProperty2 = [[NSString alloc] initWithString:#"Default Property Value"];
someProperty3 = [[NSString alloc] initWithString:#"Default Property Value"];
someProperty4 = [[NSString alloc] initWithString:#"Default Property Value"];
someProperty5 = [[NSString alloc] initWithString:#"Default Property Value"];
someProperty6 = [[NSString alloc] initWithString:#"Default Property Value"];
someProperty7 = [[NSString alloc] initWithString:#"Default Property Value"];
someProperty8 = [[NSString alloc] initWithString:#"Default Property Value"];
}
return self;
}
- (void)dealloc {
// Should never be called, but just here for clarity really.
}
#end
I want to use this singleton to use these string variables to add string in one other view and then use it to store in database in another third view.
Can someone please tell me how to reference them and store string in these variables and again access them in the third different view?
import MyManager.h where you use singleton.
[[MyManager sharedManager] setSomeProperty1:#abc"]; //for setting
[[MyManager sharedManager] someProperty1]; // for getting
or you can use like this also
MyManager *manager = [MyManager sharedManager];
manager.someProperty1 = #"abc";
NSString *str = manager.someProperty1;
How to access variables of other class? This is how I implemented it.
#interface Class1 :NSObject {
NSString *Data;
}
#property (nonatomic, retain) NSString *Data;
#implementation Class1
#synthesize Data;
someMethod{
self.Data = #"something";
}
and in Class2 :
#implementation Class2
someMethodOfClass2{
Class1 *c=[[Class1 alloc]init];
[c someMethod];
NSString *str=c.Data;
}
I get c.Data as null in Class2. Am I doing anything wrong here?
-----------myClass1--------------
#interface APIManager : NSObject {
NSString *Data;
}
#property (nonatomic, retain) NSString *Data;
-(void)getData;
#end
#implementation APIManager
#synthesize Data;
-(void)getData{
self.Data=#"response";
}
--------myClass2-------------
#interface Search : NSObject {
}
-(void)searchForItems:(NSString *)query;
#end
#implementation Search
-(void)searchForItems:(NSString *)query {
APIManager *apiManager=[[APIManager alloc]init];
[apiManager getData];
NSLog(#"%#",[apiManager Data]);
}
You should probably use self.Data = #"something" instead of self.Data = "something"
In Objective-C you have to use #"something" instead of "something". Also aren't you missing the variable declaration? In your #interface you should do something like NSString *Data.
this is my data strucure:
group [1...n] {
id,
name,
elements : [1...n]
}
I define a class for element with all properties and a class for group as:
#interface Group : NSObject {
NSInteger groupID;
NSString *groupName;
NSMutableArray *elements;
}
#property (assign, readwrite) NSInteger groupID;
#property (assign, readwrite) NSString *groupName;
#property (assign, readwrite) NSMutableArray *elements;
and single element with:
#interface Element : NSObject {
NSInteger elementID;
NSString *elementName;
}
#property (assign, readwrite) NSInteger elementID;
#property (assign, readwrite) NSString *elementName;
Both classes have properties and synthesize.
When application start I inserted data on data structure with this:
arrGroup = [NSMutableArray array];
[arrGroup retain];
Element *element1 = [[Element alloc] init];
element1.elemenID = 1;
element1.elemenName = #"Andrea";
Element *element = [[Element alloc] init];
element2.elementID = 2;
element2.elementName = #"Andrea2";
Group *group = [[Group alloc] init];
group.groupID = 1;
group.groupName = #"Grup 1";
[group.elements addObject:element1];
[group.elements addObject:element2];
[contact1 release];
[contact2 release];
[arrGroup addObject:group];
The problem is this the [group.elements addObjct:element1]. Nothing has been written on elements NSMutableArray.
Could you help me to find the error? There is a better method to retrieve structure data (groups of elemens)?
thanks for help!
Andrea
#synthesize only generates the getter and the setter for your property, you have to take care of initialization yourself if needed.
To initialize the mutable array do e.g. this in your initializer:
- (id)init { // or however it is named
if ((self = [super init])) {
elements = [[NSMutableArray alloc] init];
// ... more?
}
return self;
}
- (void)dealloc {
[elements release]; // don't forget to clean up
// ... more?
[super dealloc];
}