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Stephen Wall
Courses Plus Student 27,294 PointsWhy did you place the DispatchQueue.main.async in the DarkSkyAPIClient class?
Just curious why the call to the main thread was put into the client class and not just in the function that calls only UI updates, displayWeather():
func displayWeather(using viewModel: CurrentWeatherViewModel) {
DispatchQueue.main.async {
self.currentTemperatureLabel.text = viewModel.temperature
self.currentHumidityLabel.text = viewModel.humidity
self.currentPrecipitationLabel.text = viewModel.precipitationProbability
self.currentWeatherIcon.image = viewModel.icon
self.currentSummaryLabel.text = viewModel.summary
}
}
Seems to me that only the code that actually changes the UI should be on the main thread. Does it matter?
1 Answer
Caleb Kleveter
Treehouse Moderator 37,862 PointsIf you think about it, that code will always have to be called on the main thread because it only updates the UI, nothing else. You could have the main thread closure go around the method call, but that would have to happen every time you call the method, so it saves you some code and debugging time when you forget to call it in the main thread by placing the callback in the method.