iOS Scrap Book

Setting the title of a ViewController:

self.title = @"Clock In Time";

Setting the field placeholder:

signOutTimeField.placeholder = @"Time to Clock Out of Work";

Bending the corners of  a button

cancelJobButton.layer.cornerRadius = 8;

cancelJobButton.layer.borderWidth = 1;

cancelJobButton.layer.borderColor = [UIColor grayColor].CGColor;

cancelJobButton.clipsToBounds = YES;

Adding a Return Key to the Keyboard and Calling a method ("hideKeyBoard:") after the Keyboard Retracts

emailAddressField.returnKeyType=UIReturnKeyDone;

[emailAddressField addTarget:self action:@selector(hideKeyBoard:)

forControlEvents:UIControlEventEditingDidEndOnExit];

Defining a Method for Keyboard Retraction

-(void)hideKeyBoard: (id) sender

{

//Hiding the Keyboard

if ([sender tag] == 0) {

[emailAddressField resignFirstResponder];

}

else if ([sender tag] == 1) {

[passwordField resignFirstResponder];

}

[UIView beginAnimations:nil context:NULL];

//Setting the animation duration

[UIView setAnimationDuration:1];

CGRect rect = self.view.frame;

//Resetting the origin to 0

rect.origin.y = 0;

self.view.frame = rect;

[UIView commitAnimations];

}

Getting the ViewController to 'Roll' up and down when the Keyboard Retracts:

- (void)textFieldBegin:(NSNotification *)notif

{

UITextField *obj= [notif object];NSNumber *offsetValue=[[NSNumber alloc]

initWithFloat:obj.frame.origin.y];

[UIView beginAnimations:nil context:NULL];

[UIView setAnimationDuration:0.5];

//Get a reference to the frame

CGRect rect = self.view.frame;

//Set the origin to a new value

rect.origin.y = 60.0-[offsetValue floatValue];

//Adjust the views height

rect.size.height += [offsetValue floatValue]-60.0;

//Commit the changes to the current frame

self.view.frame = rect;

//Commit the animations

[UIView commitAnimations];

}

Adding an Observer and Removing an Observer when the view Appears and a View Disappears

- (void)viewWillDisappear:(BOOL)animated

{

// unregister for textfield notifications while not visible.

[[NSNotificationCenter defaultCenter] removeObserver:self

name:UITextFieldTextDidBeginEditingNotification object:nil];

}

-(void) viewWillAppear:(BOOL)animated

{

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector

(textFieldBegin:) name:UITextFieldTextDidBeginEditingNotification object:self.view.window];

[super viewWillAppear:animated];

}

Building an Alert

alert = [[UIAlertView alloc]

initWithTitle:@"Unverified" 

message:@"Please enter a new name and password." 

delegate:nil cancelButtonTitle:@"OK" 

otherButtonTitles:nil];

 

[alert show];

[alert release];

Trimming the Whitespace from a NSString

cellPhoneNumberString = [cellPhoneNumberTextField.text stringByTrimmingCharactersInSet:

[NSCharacterSet whitespaceCharacterSet]];

Accessing a Restful Service:

    NSString *urlString = @"http://www.samplesite.com/dtdOrdersExist.pl?";

    NSString *queryString = @"";

    queryString = [queryString stringByAppendingString:@"parameter1="];

    queryString = [queryString stringByAppendingString:p1];

    queryString = [queryString stringByAppendingString:@"parameter2="];

    queryString = [queryString stringByAppendingString:p2];

    

    // Step 5:  Make the RESTful call.

    

    urlString = [urlString stringByAppendingString:queryString];

    

    urlString = [urlString stringByAddingPercentEscapesUsingEncoding:NSASCIIStringEncoding];

    

    

    NSLog(@"ConfirmationCodeViewController URL String: %@", urlString);

    

    // {cellPhoneNumberConfirmed => $cellPhoneNumberConfirmed, cellPhoneNumber => $cellPhoneNumber, customerID => $customerID};

    

    

    // RESTFUL CODE BLOCK A

    

    

    NSURL *url = [NSURL URLWithString:urlString];

    NSData *dataURL = [NSData dataWithContentsOfURL:url];

    NSDictionary *myDict = [NSJSONSerialization JSONObjectWithData:dataURL options:0 error:nil];

    

    // Step 6:  Retrieve the data from the RESTful call

    

    NSString* numberOfOrders = [myDict objectForKey:@"numberOfOrders"];

    

    NSLog(@"Post JSON: Verified jsonCustomerID: %@", numberOfOrders);

    return numberOfOrders;

Pushing a New ViewController:

CourierViewController *cvc = [[CourierViewController alloc] 

  initWithNibName:@"CourierViewController" 

  bundle:nil];

[self.navigationController pushViewController:cvc animated:YES];

[cvc release];

Trimming Leading and trailing Whitespaces  off NSString:

NSString *trimmedString = [string stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]]

Deleting all objects from Core Data:

-(NSManagedObjectContext *)deleteCustomerObject: (NSManagedObjectContext *) context

{

    

    NSLog(@"deleteCustomerObject");

// self.navigationController = [[UINavigationController alloc] initWithNibName:@"Go_For_MeViewController" bundle:nil];

// NSManagedObjectContext* context = [fetchedResultsController managedObjectContext];

if (context == nil)

    {

context = [(Go_For_MeAppDelegate *)[[UIApplication sharedApplication] delegate] managedObjectContext];

NSLog(@"After managedObjectContext: %@",   context);

}

NSLog(@"GFMVC: Test Point 1");

    

// INPUT THE ENTITY NAME SLATED FOR DELETION HERE

    

    NSEntityDescription *entityDesc = [NSEntityDescription entityForName:@"CustomerInformation"

  inManagedObjectContext:context];

NSFetchRequest *request = [[NSFetchRequest alloc] init];

[request setEntity:entityDesc];

// NSPredicate *pred = [NSPredicate predicateWithFormat:@"(loggedIn == 1)"];

// [request setPredicate:pred];

NSError *error = nil;

NSArray *results = [context executeFetchRequest:request error:&error];

    /*

    entityDesc =  [NSEntityDescription entityForName:@"jobData"

  inManagedObjectContext:context];

[request setEntity:entityDesc];

pred = [NSPredicate predicateWithFormat:@"(jobCompleted == NO)"];

[request setPredicate:pred];

    

NSError *jobsError = nil;

NSArray *jobsResults = [context executeFetchRequest:request error:&jobsError];

    */

    

    if (results != nil && [results count] >= 0)

    {

NSLog(@"GFMVC:  Valid Request Results");

int size = [results count];

NSLog(@"GFMVC: Number of Results: %d", size);

        

        // DELETING THE OBJECTS IN THE MANAGED OBJECT CONTEXT.

for (NSManagedObject *newManagedObject in results)

        {

// [self printContext:newManagedObject];

[context deleteObject:newManagedObject];

}

        [self saveContext:context];

        return context;

        

}

else if (results == nil)

{

        

        [self saveContext:context];

        return context;

}

    [self saveContext:context];

    return context;

    

}

How to Save an object with a relationship.  BOOYAH!

        

[customerManagedObject setValue:ordersManagedObject forKey:@"customerToOrders"];

-- customerManagedObject -- the object that is the parent

-- ordersManagedObject -- the object that is the child object

-- customerToOrders -- the name of the relationship object

Setting up UIPickerView:

UIPickerView Set Up

Making UIPickerView Appear When UITextField is Selected

Printing a Date and a Time:

      timeLoggedIn = [NSDateFormatter localizedStringFromDate:[managedObj valueForKey:@"timeLoggedIn"]

      dateStyle:NSDateFormatterShortStyle

      timeStyle:NSDateFormatterFullStyle];

Changing ViewControllers with Storyboard Programatically:

If you're in a Navigation Controller:

ViewController *viewController = [[ViewController alloc] init];
[self.navigationController pushViewController:viewController animated:YES];

or if you just want to present a new view:

ViewController *viewController = [[ViewController alloc] init];    
[self presentViewController:viewController animated:YES completion:nil];

MySQL:

Alter a column:  Dropping the NOT NULL provision:

ALTER TABLE tbl_name MODIFY columnA varchar(6) NULL DEFAULT NULL;