tenqyu web service to device

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From MongoDB via JSON to UITableview

...and back

February 2012

Saturday, February 11, 12

for pleasant living

Introduction

What was the problem that I needed to solve?

1.Massive data (MongoDB)

2.Consistent way to communicate with the user(TableView)

3.Design changes and data upgrades (CoreData)

4.Simple and light data exchange(JSON)


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Application flow

MongoDBPHPJSON

CoreDataUITable

Player collection

Notification collection

Mongo Driver

Server side

Communicationinterface

Native BSONformat

Lightexchangeprotocol

Data Management

SQLite support

Difficult to learn

Known UX

No Training

Email paradigm

Master/Detail


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The iPhone side

We need to cover 3 areas

1. Connection to the web service

2. Transformation into CoreData

3. Presentation for TableView


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ViewController

Infrastructure overview

How are the different parts supposed to co-exist?IBOutlet UITableView* newsTable;

IBOutlet UITableViewCell *tblCell;

NSFetchedResultsController *fetchedResultsController;!NSManagedObjectContext *managedObjectContext;

UITableView

WebAccess

configureCell

cellForRowAtIndexPath

NSFetchedResultsController

didChangeObject

2. connectionDidFinishLoadingnotificationsReceived

findOrCreateNews- (BOOL) findOrCreateNews : (NSDictionary *) dic inManagedObjectContext:(NSManagedObjectContext *) context ;

Implements the protocolfunction

notificationsReceived

QyuWebDelegate (@Protocol of WebAccess)UITableViewDelegateUITableViewDataSourceNSFetchedResultsControllerDelegate

calls

calls

Initiate Object1. updateNews

calls

Delegatelist


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if (qyuDelegate.updateNotification==TRUE) { NSLog(@"Trying to update"); QyuWebAccess *webNotifications = [[QyuWebAccess alloc] initWithConnectionType:@"notify"]; [webNotifications setDelegate:self]; [webNotifications updateNews:qyuDelegate.usrQyu.mongoId]; }

Web Service Connection

12

3

(2) Simply sets a string to “notify” which is checked during didFinishedLoading

During loading (viewWillAppear)


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Web Service Connection

Best practices : Keep a separate object to organize the WebAccess

Relevant items: 1.A JSON Parser2. A formal protocol spec (delegate pattern)3. The NSURLConnection items (Connection, Data)4. A NSDictionary for the JSON data

https://github.com/stig/json-framework/




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Setting up the connection

NSString *baseURL = @"http://choose.tenqyu.com/notifications.php";

NSString *idstr = [@"id=" stringByAppendingString:@"getNotifications"]; NSString *mongoStr = [@"&mongoId=" stringByAppendingString:mongoId]; NSString *requestVars = [idstr stringByAppendingFormat:@"%@", mongoStr];

NSData *requestData = [NSData dataWithBytes: [requestVars UTF8String] length: [requestVars length]]; // Create the request. NSMutableURLRequest *theRequest=[NSMutableURLRequest requestWithURL:[NSURL URLWithString: baseURL] cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:60.0]; // create the connection with the request // and start loading the data [theRequest setHTTPMethod: @"POST"]; [theRequest setHTTPBody: requestData]; NSURLConnection *theConnection=[[NSURLConnection alloc] initWithRequest:theRequest delegate:self];

1. Set the base URL address

2. Set the HTTP POST vars to prepare the data item.

3. Prepare the NSData item and Connection Items

4. Initialize the connection. Results will be in connectionDidFinishedLoading


https://choose.tenqyu.com/playerNotifications.php

https://choose.tenqyu.com/playerNotifications.php

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Did Finished Loading?

} else if(self.connectionType == @"notify") { NSString *jsonString = [[NSString alloc] initWithData:receivedData encoding:NSUTF8StringEncoding]; self.jsondata = [jsonString JSONValue];

if(delegate && [delegate respondsToSelector:@selector(notificationsReceived:)]) { [delegate notificationsReceived:self.jsondata];

} else {

NSLog(@"Problem with the delegation in connectionDidFinishLoading loading"); }

- (void)connectionDidFinishLoading:(NSURLConnection *)connection{

[...]1

3

NSDictionary Object

2


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ViewController





UITableView

WebAccess

configureCell

cellForRowAtIndexPath


didChangeObject





QyuWebDelegateUITableViewDelegateUITableViewDataSourceNSFetchedResultsControllerDelegate

calls

calls


calls

Delegatelist


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Delegate has been triggered

- (void)notificationsReceived:(NSDictionary *)resultData{ for (NSDictionary* notification in resultData) {

[self findOrCreateNews:notification inManagedObjectContext:qyuDelegate.managedObjectContext];

} qyuDelegate.updateNotification=FALSE;}

1

2

This function needs to be implemented in the Viewcontroller

Loop over the NSDictionary Items

Upsert the TableViewItems


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CoreData

Core Data is just managing the flow, not storing data

News User

Persistent Store 1

Persistent Store 2

Managed Object Context

ViewController Application Delegate

FetchedResultController

FetchedResultController1 2

SQLiteNews

SQLiteUser


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The “save” in findAndCreateNews

NSFetchRequest *request = [self.fetchedResultsController fetchRequest];! request.entity = [NSEntityDescription entityForName:@"News" inManagedObjectContext:context]; request.predicate = [NSPredicate predicateWithFormat:@"mongoId = %@", nItem.mongoId];

NSError *error = nil; NSArray *items = [[context executeFetchRequest:request error:&error] lastObject]; !!! if (!error && !items && nItem ) { ! ! NSManagedObject *newManagedObject = [NSEntityDescription insertNewObjectForEntityForName:@"News" inManagedObjectContext:context];! ! [newManagedObject setValue:nItem.nText forKey:@"nText"];

[...]

! ! [newManagedObject setValue:nItem.mongoId forKey:@"mongoId"];! ! [newManagedObject setValue:[NSDate date] forKey:@"pushDate"];! !! ! NSError* error; Here we now simply save ! !

if (![context save:&error])! ! ! {! ! ! // Handle the error.! ! ! NSLog(@"Unresolved error %@, %@", error, [error userInfo]);! ! ! exit(-1);! ! }!! ! return TRUE;! } else{! !


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ViewController





UITableView

WebAccess

configureCellcellForRowAtIndexPath


didChangeObject





QyuWebDelegateUITableViewDelegateUITableViewDataSourceNSFetchedResultsControllerDelegate

calls

calls


calls

Delegatelist


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The TableView

- (void)configureCell:(UITableViewCell *)cell atIndexPath:(NSIndexPath *)indexPath{

NSManagedObject *managedObject = [self.fetchedResultsController objectAtIndexPath:indexPath];

cell.textLabel.text = [[managedObject valueForKey:@"nText"] description]; cell.detailTextLabel.text = [[managedObject valueForKey:@"longText"] description]; cell.textLabel.font = [UIFont fontWithName:@"ArialRoundedMTBold" size:16];

UIImage *cellicon=[UIImage imageNamed:@"ux1.png"] ; [[cell imageView] setImage:cellicon];

}

1. Retrieve the managedObject from the FetchedResultscontroller

2. Get the “fields” in the managedObject and store them in the cell


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Thank you!


tenqyu web service to device

Technology