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8:53
Combine and Diffable Data Sources
Building Reactive Applications With Combine
In 2019, Apple introduced another powerful API alongside the Combine framework, diffable data sources. Diffable data sources make it almost trivial to build performant table and collection views. In this episode, I show you why diffable data sources work well with the Combine framework. I won't cover diffable data sources in detail in this series, but the API is straightforward and easy to pick up.
in Programming
8:32
Reactifying the Week View Controller
Building Reactive Applications With Combine
In this and the next episode, we shift focus to the week view controller. Populating the week view requires a different approach. It contains a table view and the week view model manages an array of WeahterDayData objects. Even though the approach is different, the patterns we apply are similar.
in Programming
11:07
Combining Publishers with Zip and Combine Latest
Building Reactive Applications With Combine
The Combine framework defines a range of operators to combine publishers. Combining publishers is a common pattern in reactive programming. In this episode, we improve the efficiency of the RootViewModel class by combining multiple publishers using the zip and combineLatest operators.
in Programming
8:35
Reducing State with Subjects
Building Reactive Applications With Combine
We ran into several issues in the previous episode. The assign(to:on) and sink(receiveValue:) methods are convenient, but they don't always cut it. We need a solution that is robust and scales with the complexity of the project.
in Programming
7:07
Reducing Complexity and Code Duplication
Building Reactive Applications With Combine
In this episode, we optimize the implementation of the day view controller and the day view model. There are a few details we need to take care of. First, the day view controller should display an error message when its view model emits an error. Second, the day view controller should only display its activity indicator view if it has no weather data to display. Let's tackle these problems one by one.
in Programming
8:50
Bridging Imperative and Reactive Programming
Building Reactive Applications With Combine
There are a few user interface issues we need to address in this episode. The day view controller no longer shows its activity indicator view while it is waiting for weather data and the user interface elements that show the weather data should only be shown when there is weather data to display. Let's find out how we can resolve these issues.
in Programming
7:42
Driving the User Interface with Publishers
Building Reactive Applications With Combine
In the previous episode, we put the foundation in place to reactify the DayViewController class. In this episode, you learn how to use publishers to drive the user interface of an application.
in Programming
8:36
Hiding Implementation Details with Type Erasure
Building Reactive Applications With Combine
The root view controller displays the weather data the publisher emits. Every time the publisher emits weather data, the child view controllers of the root view controller receive the weather data and display it to the user. This works fine, but we can make it more reactive.
in Programming
6:27
Using Publishers to Push Data
Building Reactive Applications With Combine
We made good progress in the previous episodes, but we need to make some changes to the RootViewController and RootViewModel classes. We address three issues in this episode. First, the RootViewController class shouldn't be aware of CLLocation objects. Second, the RootViewModel class should expose a publisher that emits weather data. Third, we need to restore the pull-to-refresh feature. Let's get started.
in Programming
7:33
Filtering and Transforming Elements with Operators
Building Reactive Applications With Combine
The Published property wrapper lowers the barrier to start integrating the Combine framework into a project. There are a few details you need to take into account, though. Remember from the previous episode that we need to address two issues. Let's look at the first issue.
in Programming
8:01
Reactifying Swift with the Published Property Wrapper
Building Reactive Applications With Combine
The Cocoa frameworks use a range of asynchronous interfaces, including the target-action pattern, key-value observing, notifications, and callbacks. We can leverage the Combine framework to create a single, unified interface for asynchronous programming. This opens up a number of compelling advantages.
in Programming
6:45
Understanding the Life Cycle of a Subscription
Building Reactive Applications With Combine
You learned in the previous episode that a publisher sends zero or more values. A publisher emits an error if something goes wrong and, if the publisher is finite, it can send a completion event. In this episode, we continue exploring the relationship between publishers and subscribers. We zoom in on the life cycle of a subscription.
in Programming