https://github.com/dreamengine/DECategories
DECategories is a collection of useful categories for the modern iOS developer. These categories make the creation process easier and faster by providing a multitude of conveniences. They are also divided into cocoapods subspecs for individual use.
Below is a list of included categories and what they provide. UIView, UINib, and UIViewController instantiation have particularly useful conveniences.
Problem: You have an image but aren't sure if it's a png or gif.
Solution: Just use -imageDataMimeType on the image's NSData representation and get a mime type string (e.g. @"image/png").
Problem: You want to store an array of objects but don't want to retain them (e.g. a list of prioritized delegates).
Solution: Use +mutableArrayUsingWeakReferences and stash away!
Problem: You are populating a dictionary, but some of the objects are optional and you're tired of safety checking to make sure that each one is non-nil before adding them.
Solution: Use -setObjectIfNonNil:forKey:, and your object will only be added if it is non-nil.
Problem: You want to store a set of objects but don't want to retain them (e.g. an unordered list of delegates).
Solution: Use +mutableSetUsingWeakReferences and stash away!
Problem: Your app only ever uses the default notification center [NSNotificationCenter defaultCenter] and you are so very tired of always having to reference it. You also tire of having to manually package NSNotification objects whenever you want to send data.
Solution: Just use +postNotificationWithName:, +postNotificationWithName:object:, and +postNotificationWithName:object:userInfo:, which will automatically package an NSNotification for you and send it out to the default notification center.
Problem: You have an absolute file path, but you only want the file's path relative to some directory. (E.g. your app utilizes user-provided files and folders and you want to store certain paths, but an app update may change where those files are stored and break the absolute paths you saved.)
Solution: Use -stringWithPathRelativeTo: and get the relative path.
Problem: You want the background color of your UIButton to change as the control state changes.
Solution: Use -setBackgroundColor:forState:.
Problem: You want to create a UIColor from a hex string, or you want to make a UIColor without all the verbosity.
Solution: For creating a hex string, use colorWithHexString:, or you can use the convenience function UIColorFromHexString(NSString).
All convenience functions:
UIColorFromValues(float, float, float),UIColorFromValuesWithAlpha(float, float, float, float),UIColorFromIntValues(int, int, int)(0-255),UIColorFromIntValuesWithAlpha(int, int, int, int)(0-255), andUIColorFromHexString(NSString).
Problem: You want to be able to manually cancel a UIGestureRecognizer.
Solution: Use -cancel.
Problem: You want to create a UIImage that's filled with a certain color.
Solution: Use +imageWithColor:ofSize:.
Problem: You want to resize a UIImage, perhaps to save on memory if the image is too large.
Solution: Use +imageWithImage:scaledToSize:, or -resizedImageScaledToSize:.
Problem: You want to add a tint to a UIImage.
Solution: Use -imageTintedWithColor:fraction:.
Problem: You want to inflate an object from a nib file without all the hassle.
Solution: Use +firstObjectWithNibName:, which will automatically create a UINib object and send the first item in that nib back to you.
Problem: You have a table view with short cell contents, and you don't much care for the empty cells and lines that are drawn underneath your cells.
Solution: Use -applyHideEmptyCellsStyle.
Problem: You want to directly get and set x, y, width, and height values without going through the frame. Or, you want to inflate a UIView from a nib file and wish it was just a little easier.
Solution: x, y, width, and height properties are provided. To quickly instantiate from a nib file, use +viewFromNib (just make sure that your nib file matches the class name).
Problem: You don't know who the first responder is, but you sure would like to find out.
Solution: Use -findFirstResponder. (If you want to resign the first responder and don't care who it is, you can just use the built-in -endEditing: on your main UIView container).
Problem: You wish there was a factory method for easily constructing UIViewController instances.
Solution: There is! You can simply use +controller, and it will automatically attempt to load a nib file with your class's string representation. If a nib file is not found, it will programmatically instantiate your controller.