Converting jsonarray (having different type) to model array using JSONModel Library

Question

I have one problem in converting JSON array to model. I am using JSONModel library.

@protocol PTTemplateModel <NSObject>

@end

@protocol PTProfileTemplateModel <PTTemplateModel>

@end

@protocol PTCategoryTemplateModel <PTTemplateModel>

@end

    @interface PTTemplateModel : JSONModel
    @property (nonatomic, assign) TemplateType type;
    @property (nonatomic, copy) NSString* templateID; 
    @end

    @interface PTProfileTemplateModel : PTTemplateModel
    @property (nonatomic, copy) NSString* logoURL;
    @property (nonatomic, copy) NSString* title;
    @end

    @interface PTCategoryTemplateModel : PTTemplateModel
    @property (nonatomic, strong) NSString* category;
    @end

    @interface PTModel : JSONModel
    @property (nonatomic, copy) NSString* title;
    @property (nonatomic, strong) NSArray< PTTemplateModel>* templates; // PTTemplateModel

Here templates array can have both PTProfileTemplateModel and PTCategoryTemplateModel.

JSON Input:

{"title":"Core","templates":[{"type":0,"templateID":"","logoURL":"", "title":"data"},{"type":1,"templateID":"","category":"DB"}]}

What I need is according to type I have to get CategoryTemplate or ProfileTemplate. But after conversion I am getting just PTTemplateModel type.

I know that I have specified protocol type as PTTemplateModel. But how do I get different type of model according to given data.

I tried:

1. @property (nonatomic, strong) NSArray< PTTemplateModel>* templates;

2. @property (nonatomic, strong) NSArray<PTProfileTemplateModel, PTCategoryTemplateModel>* templates;

3. @property (nonatomic, strong) NSArray< PTTemplateModel , PTProfileTemplateModel, PTCategoryTemplateModel>* templates;

None of them works.

Any suggestions?

Answer 1

Why not try BWJSONMatcher, it helps you work with json data in a very very neat way:

@interface PTModel : NSObject<BWJSONValueObject>
@property (nonatomic, strong) NSString *title;
@property (nonatomic, strong) NSArray *templates;
@end

@interface PTTemplateModel : NSObject
@property (nonatomic, assign) TemplateType type;
@property (nonatomic, strong) NSString *templateID;
@property (nonatomic, strong) NSString *logoURL;
@property (nonatomic, strong) NSString *title;
@property (nonatomic, strong) NSString *category;
@end

In the implementation of PTModel, implement the function typeInProperty: declared in protocol BWJSONValueObject:

- (Class)typeInProperty:(NSString *)property {
    if ([property isEqualToString:@"templates"]) {
        return [PTTemplateModel class];
    }

    return nil;
}

Then you can use BWJSONMatcher to get your data model within one line:

PTModel *model = [PTModel fromJSONString:jsonString];

Detailed examples of how to use BWJSONMatcher can be found here.