I'm new in iPhone development, can you advice me how to serialize AdressBook records?
I have read stackoverflow - How do I serialize a simple object in iPhone sdk, but I still have questions:
should I extend ABRecordRef? Is it possible? Or should I implement own class NSObject?
(similar question was on Mac forums and was left without answer)
Thank you!
ABRecord is an opaque C type. It is not an object in the sense of Objective-C. That means you can not extend it, you can not add a category on it, you can not message it. The only thing you can do is call functions described in ABRecord Reference with the ABRecord as a parameter.
You could do two things to be able to keep the information referenced by the ABRecord arround:
Get the ABRecords id by ABRecordGetRecordID(). The ABRecordID is defined as int32_t so you can cast it to an NSInteger and store it wherever you like. You can later get the record back from ABAddressBookGetPersonWithRecordID () or ABAddressBookGetGroupWithRecordID(). But aware, the record could be changed or even deleted by the user or another app meanwhile.
Copy all values inside the record to a standard NSObject subclass and use NSCoding or other techniques to store it. You will then of cause not benefit from changes or additions to the record the user could have made.
Of cause you can combine both approaches.
Related
I want to iterate over the properties of my models in Objective-C. I tried this. Created PropertyUtil class with method classPropsFor:(Class)klass. Please find the attachment. Used objc/runtime.h. The code which I got from the net. In my viewcontroller I am doing this. [PropertyUtil classPropsFor:[self.user class]];. self.user is User model class. What I want to know is how can i iterate over the properties of my models, let's username, password and those values.
You may want to manually list all properties your model has.
Just add a method to your model:
+(NSArray*) propList {
return #[#"prop1", #"prop2"];
}
Then just use key-value coding to get the value
[someObject valueForKey:#"prop1"];
That's pretty straight and simple way if you wish to avoid Obj-C meta functions. Since you add your properties manually anyway, you may also add them in your list as well.
That's of course, if you don't have a large amount of models already and you wish do them all at once.
I'm using Realm.io as database and I need a select * from all_tables in Realm.
I mean a method returning an RLMArray, but I have not found anything about this.
I need the class reference, such as Realm Browser.
Thanks.
You can use [realm.schema.objectSchema valueForKey:#"className"] to get an NSArray of all of the RLMObject subclasses used in the Realm.
I don't believe this is possible at the moment. You should request it on github. In the mean time you will have to create your own. First you have to know that an RLMArray can only hold one type so if in these different tables there are different types than you can not do the following. It would be as easy as creating your own method for this. It would consist of getting all objects from each table and just inserting them into the RLMArray; If your tables don't have the same type then you will have to use a NSMutableArray or an NSArray.
I am planning on creating my app in a 'Model-View-Controller'(MVC)-style, and in the end, for me at least, this means that all data is stored in the controller-class. Let's say I have a class Player, and the player has several objects of class Weapons or Equipment or whatever. The initialization of Controller* stores the player(s), so if I can store/save only the Controller-object over time, even if the app or the device restarts, that would be nice. I did this in Java one, I put in Serialization = 100L;(or something like it) in the top of the file of every object that would be included when saving the Controller-object, and it worked perfectly. Is this possible in ios/cocoa-touch/objective-c?
I have read and used Core Data (not very much), but that is just a database-table, sql?, which would have me extract every piece of information of every object?
For instance, if the object Player* has a member NSString *name;, I would have to save the actual string in Core Data, instead of saving the object of the player? Like, varchar.
If there is any way to store an entire custom object on the device for further use, I would very much like to know what it's called, and where I can read about it/tutorials.
Read up on the NSCoding protocol. You can make your object complient to it, then serialized it and save it to a file. Later you can restore it to the same state by using a decoder. For sure some other posts that cover this topic on SO.
I'm about to work on a Objective-C game projects, and I'm curious to what's the options for getting constant data into the game. I've worked for many years as a Flash dev and in Flash I would just simply setup a class file and put in it objects like this...
static var arrowData:Object = {
elementType:"projectile",name:"arrow",sourceType:"library", imgSource:"arrow", imageSourceSub:"",cellsX:1, cellsY:1,
bounderyType:"none",bounderyLeft:0,bounderyRight:1200, bounderyTop:80, bounderyBottom:580,
position:{rotateToDir:false,positionType:"movieclip", randomX:false, randomY:false, endRandomX:600, endRandomY:400, startX:0, startY:0},
visual:{imgLabel1:"", imgNumFrames1:15,imgFramesLoop1:true,runOnFrame1:0,runOnFrameFN1:"",runOnLastFN1:""},
movement:{moveType:"arc", maxDistance:400, atTarget:"remove", target:"mouse", targetData1:"mouseX", targetData2:"none"},
physical:{physData:"spritesLayer"},
interactive:{interactionType:"rect", removeOnInteraction:true, interactionResult:"ingame", interactionData1:"badGuysArray", interactionData2:"projectileCollision"},
character:{damage:10}
};
I've Objects inside Objects, but there doesn't seem to be any clear way to do the same with Objective-C, so my questions are...
Is there any way to do the same as the above in Objective-C?
What are the other methods for getting data into Objective-C? XML?
How do iOS game devs usually store their constant game data?
I'm going to be using the parse hosting service with this project, are there
options for using that to store the data and loading it from there?
As the comment by #tc touched on, the common way to maintain groups of related info is in NSDictionaries (or their mutable cousins). Dictionaries can also nest. You have two ways to save these easily: as plists per comment or in the 'defaults' system. The latter is more restrictive on the types of data it stores. Apple also has a class that will convert between JSON and native objects. I have no experience with question 4 - hope others can answer that.
I'll ask in the form of a hypothetical, which might make it easier for me to explain.
I have a class called Person, and in this has three fields:
NSString *name;
NSDate *dateOfBirth; and
NSMutableArray *friends.
An example object is this:
name = "John Smith"
dateOfBirth = 01/04/1985
friends = "Simon Scott"; "Jennifer Lane"; "Mary Firth"
Once the user has filled the NSMutableArray with the data they want, what would be the best way to save this data to the iPhone? I would anticipate that there could be up to 100 instances of the Person object, and all that will be required is the displaying of this data in a UITableView and giving the user the ability to add and remove entries at their will.
I have seen multiple suggestions on this site, which include NSDictionaries and using the writeToFile method, but before I research one of these, I was hoping someone could point me in the right direction? I would like to ensure that I'll be using the easiest and most appropriate method that's out there.
Many thanks.
Please take a look at the Property List Programming Guide. As long as you stick with a core set of object types for your data, you can write and read your data from a file or URL in one line, like this:
[people writeToURL:someURL atomically:NO];
The types you've mentioned in your question (strings, dates, arrays, dictionaries) can all be written to a property list.
#Achiral,
It really depends on what you want to do with the data and how concerned you are with the flexibility of your code.
However, my recommendation would be to use CoreData to make an SQLlite database and make a 'Person' entity with the properties that you list above. I don't know if you are familiar with CoreData, but it is highly optimized on iOS and is pretty easy to use, since it has a pretty simple 'fill in the blanks' style form for creating the data models. You should also note that CoreData is a well accepted and supported way to store data in an iOS and OS X app.
I hope this helps.