Hi Friends,
I'm trying to learn some Objective-c. Here's what I've got so far.
Creating dictionaries
JavaScript Version:
var jamund = {
pic: "http://a0.twimg.com/profile_images/1164437235/IMG_0803.jpg",
name: "Jamund Ferguson",
position: "Sr. JavaScript Developer",
yearsEmployed: "1",
twtiter: "xjamundx",
email: "jamund@gmail.com"
};
Objective-C Version:
NSDictionary *jamund = [NSDictionary dictionaryWithObjectsAndKeys:
@"http://a0.twimg.com/profile_images/1164437235/IMG_0803.jpg", @"pic",
@"Jamund Ferguson", @"name",
@"Sr. JavaScript Developer", @"position",
@"1", @"yearsEmployed",
@"xjamund", @"twitter",
@"jamund@gmail.com", @"email", nil];
Splitting a string into an array of parts
JavaScript Version:
var myString = "This is a test";
var myWords = myString.split(" "); // ["this", "is", "a", "test"]
console.log("First word: " + myWords[0]); // First word: This
Objective-C Version:
NSString *myString = @"This is a test";
NSArray *myWords = [myString componentsSeparatedByString:@" "];
NSLog(@"First word: %@", [myWords objectAtIndex:0]); // First word: This
Getting the first name in a full name string
JavaScript Version:
var name = "Jamund Ferguson";
console.log("Location: " + name.indexOf(" ")); // Location: 6
var firstName = name.slice(0, name.indexOf(" ")); // Jamund
Objective-C Version:
NSString *name = @"Jamund Ferguson";
NSRange r = [name rangeOfString:@" "];
NSLog(@"Location: %i", r.location); // Location: 6
NSLog(@"Range: %@", NSStringFromRange(r));
NSLog(@"First name: %@", [name substringToIndex:r.location]);// First name: Jamund
http://stackoverflow.com/questions/256460/nsstring-indexof-in-objective-c
Creating a Simple Array of Strings
Objective-C Version:
NSArray *friends = [NSArray arrayWithObjects: @"Cat", @"Dog", @"Mouse", @"House", @"Pals", @"Rob", nil];
JavaScript Version:
var friends = ["Cat", "Dog", "Mouse", "House", "Pals", "Rob"];
WTFs!?
"Missing sentinel in function call" - Just means that you must end your array with a nil (see above).
Adding the same subview to a view multiple times in row leads to it only being added once:
int j = [[self.view subviews] count];
NSLog(@"You have %i subviews loaded", j); // You have 2 subviews loaded
[self.view addSubview:loadingView];
[self.view addSubview:loadingView];
[self.view addSubview:loadingView];
[self.view addSubview:loadingView];
[self.view addSubview:loadingView];
[self.view addSubview:loadingView];
[self.view addSubview:loadingView];
[self.view addSubview:loadingView];
[self.view addSubview:loadingView];
[self.view addSubview:loadingView];
[self.view addSubview:loadingView];
[self.view addSubview:loadingView];
[self.view addSubview:loadingView];
[self.view addSubview:loadingView];
j = [[self.view subviews] count];
NSLog(@"You have %i subviews loaded", j); // You have 3 subviews loaded
This means that we don't have to worry about checking if a view has been added before adding it again, which is actually pretty convenient!
A great tutorial:
http://cocoadevcentral.com/d/learn_objectivec/
Another tutorial:
http://developer.apple.com/library/ios/#referencelibrary/GettingStarted/Learning_Objective-C_A_Primer/
