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shkeyvalueobserverblocks

Welcome to the SHKeyValueObserverBlocks documentation page! Here, you will find an in-depth guide and reference for using the SHKeyValueObserverBlocks library in your iOS projects. With SHKeyValueObserverBlocks, you can easily observe changes in key-value coding compliant objects using modern Swift closures.

Table of Contents

Installation

To integrate SHKeyValueObserverBlocks into your iOS project, you can use either Carthage or CocoaPods.

Carthage

github "shvoykin/SHKeyValueObserverBlocks"

CocoaPods

pod 'SHKeyValueObserverBlocks'

Usage

Using SHKeyValueObserverBlocks in your iOS project is simple and straightforward. First, import the library into your Swift file:

import SHKeyValueObserverBlocks

Now, you can start observing changes in key-value coding compliant objects. The library provides an extension on NSObject, which lets you use the observe(_:options:changeHandler:) method to specify the key paths you want to observe. An observer is automatically added to the object which will fire the provided closure whenever the value for the specified key path changes.

The observe(_:options:changeHandler:) method accepts the following parameters:

  • keyPath: The key path to observe.
  • options: An optional set of NSKeyValueObservingOptions that determine the observation behavior (default is []).
  • changeHandler: A closure that will be triggered when the observed key path changes. The closure takes two parameters: the new value and the old value.

Example

Let’s see an example of observing a key path:

// Create an object to observe
let observedObject = SomeObject()

// Add an observer for the given key path
observedObject.observe(\.someKeyPath) { (newValue, oldValue) in
    print("Value changed from \(oldValue) to \(newValue)")
}

In the above example, whenever the value of someKeyPath changes in observedObject, the provided closure will be executed, printing the new and old values to the console.

API Reference

Below is a list of the available methods and properties provided by the SHKeyValueObserverBlocks library.

NSObject Extensions

observe(_:options:changeHandler:)

Adds an observer to the object for changes in the specified key path.

FAQ

How can I observe multiple key paths?

You can call the observe(_:options:changeHandler:) method multiple times, specifying the desired key paths to observe.

What if I want to stop observing a key path?

The SHKeyValueObserverBlocks library provides a convenience method to stop observing a key path called removeObserver(_:forKeyPath:). You can call this method on the observed object passing the key path to stop observing.

License

SHKeyValueObserverBlocks is available under the MIT license. See the LICENSE file for more information.