After growing tired of always writing a lot of (what felt like) boilerplate Objective-C over and over again, I decided to make a bunch of useful utilities to make my life easier, and by proxy, yours too. This is an ever-growing repository of useful functions that should help you in development. I encourage you to read through their implementation so that you understand what's happening in the background and don't get comfortable with an extremely abstracted up representation of those functions.
All of the important classes are located in the Classes top-level directory in this repository. These are the ones you'll need:
NSString+BGStringUtilities.{h,m}NSScanner+BGScannerUtilities.{h,m}UIView+BGViewUtilities.{h,m}BGSystemUtilities.{h,m}BGUtilities.h
The last class, BGUtilities.h is an aggregate of all of the classes above it, meaning you only have to #import "BGUtilities.h" in any classes you'd like to get all of the methods in this suite.
Cocoapods
pod 'BGUtilities'
- Suite of Utilities
- Unit Tests
- License
There's a lot of cool things you can do with NSString, but the only problem is that sometimes you have to dig down and use some other NSObject classes to do them. Here is a growing list of methods that I think should help any iOS developer handle NSString manipulations.
Contains Searches
The two methods contains: and containsAnyInArray: are the methods used to check for existence of substring(s) inside of an NSString. These comparisons are case-insensitive, so capital letters register the same as lowercase. Here's how you use them:
NSString *mainString = @"Contains";
BOOL containsSubString = [mainString contains:@"Con"];
BOOL containsAnySubString = [mainString containsAnyInArray:@[@"BG",@"Con"]];Regular Expressions
Regular Expressions can be very powerful tools despite the insanely disgusting syntax. With that said, here is the main method for evaluating whether a string matches a regular expression:
BOOL matches = [@"HelloWorld" matchesRegex:@"{2,10}"];You can also enumerate your matches inside of a string as well:
[@"1 2 3 4 5" enumerateRegexMatches:@"\\d+" usingBlock:^(NSString *match, NSInteger index, NSRange matchRange, BOOL *stop) {
// Use the match or range how you need to
// Set stop = YES to end the enumeration loop
}];Beyond just stock regular expression evaluation, there is also a convenience method for determing if an email address is valid too.
BOOL isValid = [@"[email protected]" isValidEmail];Words
Sometimes you want to evaluate text as if it conceptually contains words, and then act on them. There are a few convenience methods here as well for determining the number of words any NSString contains.
NSString *sentence = @"This sentence contains 6 unique words words.";
NSArray *words = [sentence words];
NSSet *uniqueWords = [sentence uniqueWords];
NSInteger *wordCount = [sentence numberOfWords];Beyond these shorthand methods, there is also a main method used to enumerate all of the words inside of a sentence:
NSString *sentence = @"This sentence contains 6 unique words words.";
[sentence enumerateWordsUsingBlock:^(NSString *word, NSInteger index, BOOL *stop){
// Do something with word here.
// Set stop = YES to break the enumeration loop.
}];Concatenate NSStrings
Concatenating can be quite annoying in Objective-C, and I'm here to partially ease the pain. Unfortunately we don't have the simplicity of say @"Hello" + @" World", but it is better than using stringWithFormat:. Hopefully you enjoy the compromise:
NSString *concatenated = [NSString stringByConcatenating:@"Hello",@" World",nil];Scan a string that is between two other strings
NSScanner is notoriously cumbersome to use for this simple use case. Say you have a string that looks like this: @"Hi my name is (Ben)!" and you just want to get the characters between the two parentheses. Here's how you'd grab that info:
NSScanner *scanner = [[NSScanner alloc] initWithString:@"Hi my name is (Ben)!"];
NSString *name = @"";
[scanner scanBetweenString:@"(" andString:@")" intoString:&name];Enumerate substrings between two strings
Now, say you have a weird string that's formatted like so: @"Somebody named (Jane) has {apples, bananas, oranges, pears, peaches} in her basket." and you have a Person object where you'd like to assign a name and their various fruits to them. Here's how you'd go about this, assuming a Person object with a Name (string) property and a Fruits (NSMutableArray) property:
// Make a person
Person *newPerson = [[Person alloc] init];
// Set up scanner
NSScanner *scanner = [[NSScanner alloc] initWithString:@"Somebody named (Jane) has {apples, bananas, oranges, pears, peaches} in her basket."];
NSString *name = @"";
// Scan name
[scanner scanBetweenString:@"(" andString:@")" intoString:&name];
newPerson.Name = name;
// Scan fruits
[scanner enumerateSubstringsBetweenString:@"{" andString:@"}" separator:@", " block:^(NSString *subString, NSInteger *index, BOOL *stop) {
[newPerson.Fruits addObject:subString];
}];Convenience is key when it comes to these methods for UIView. The first ones we start off with are for UI considerations.
Shadows
Everyone loves shadows. Every developer hates coding them. Through QuartzCore it's not too terrible to make shadows, but what should be a very quick method call ends up taking about 5 or 6 lines to make a shadow correctly. This is why it's important to not keep rewriting this UI boilerplate code. Let me do that for you:
UIView *someView;
// Customize a shadow
[someView addShadowWithOffsetSize:CGSizeMake(1.0,1.0) color:[UIColor blackColor] opacity:0.5 radius:0.0];That method call handles just about all of the customization you need to add a shadow to a view. However, if what you want is even faster and has less tinkering involved, I made a quick shorthand method for this as well. It uses the exact same parameters as the above code snippet. Obviously, you can change this depending on whatever you think a default shadow should look like:
[someView addShadow];Borders
Borders are just as easy to add as shadows. Using this method creates a border that is inset in the view, meaning that if your view is 300px wide by 150px tall, after you add your border your view is still 300x150.
[someView addBorderWithWidth:1.0 color:[UIColor blueColor]];Corner Raidus
This method doesn't add much, since setting the corner radius on a view is only one line of code anyways. However, it's not the most intuitive to go through the layer at first, so using this method should make a little more sense and probably take away time from having to think about what to go through for just adding rounded corners.
[someView setCornerRadius:7];Animations
As iOS progresses, high-quality animations are getting easier and easier to accomplish. However, I felt like there were some stock animations that could be made easier to directly do without doing the usual 4-5 lines necessary to make something happen. The first of these animations is fading in and fading out. Here's some ways to do this:
UIView *someView;
// Fade In With Duration and a Completion Block
[someView fadeInWithDuration:0.25 completion:^(BOOL finished){
// Do something upon completion!
}];
// Fade In With Duration
[someView fadeInWithDuration:0.25];
// Stock Fade In - 0.25 seconds and no completion block
[someView fadeIn];
// Fade Out With Duration and a Completion Block
[someView fadeOutWithDuration:0.25 completion:^(BOOL finished){
// Do something upon completion!
}];
// Fade Out With Duration
[someView fadeOutWithDuration:0.25];
// Stock Fade Out - 0.25 seconds and no completion block
[someView fadeOut];These are all dandy, but what if you want to fade in/out an entire collection of UIViews? Well, use this master method to accomplish that:
[UIView fadeViews:@[someView,someOtherView] withDuration:0.25 fadeIn:YES completion:^(BOOL finished){
// Do something upon completion!
}];CGRect Methods
Typing out someView.frame.size.height can get very annoying, very fast. So here's a few shorthand methods that make life easier when doing a lot of frame transformations and lookups.
float height = [someView height];
float width = [someView width];
CGPoint origin = [someView origin];
float x = [someView xOrigin];
float y = [someView yOrigin];Separator Bar
This one might be the most useless or actually a very useful method for you. I've spent too many times adding a 1px tall view that acts as a visual separator. So, here's a useful function I made to add one wherever you want:
UIView *separator = [UIView separatorWithWidth:300 origin:CGPointMake(10,10) color:[UIColor darkGrayColor]];Some helper methods I've created and curated don't really belong in categories, but are more appropriate for class methods that relate to the system in general - less to classes like UIView or NSString.
Screen Width & Height
You can grab the screen width and height for the current orientation of the device like so:
float width = [BGSystemUtilities screenWidth];
float height = [BGSystemUtilities screenHeight];Current iOS Version
float versionNumber = [BGSystemUtilities iOSVersion];Included in the main project is a suite of unit tests designed to quickly check and verify that these methods are actually doing what they say they're doing. I also have these tests running on a Travis CI integration server, where pull requests and other modifications can be tested and validated before ever merging into the main repository.
BGUtilities is licensed under the standard MIT License:
Copyright (C) 2013 by Benjamin Gordon
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.