当设备处于暗模式时，将应用程序切换到暗模式 | Swift iOS 13

Question

When dark mode is already enabled on the device and I open my app all of the color sets that specify dark mode are not being applied:

But when having the app already open and switching to Dark Mode from Control Center, the following code changes the color:

override func traitCollectionDidChange(_ previousTraitCollection: UITraitCollection?) {
    super.traitCollectionDidChange(previousTraitCollection)
    guard let previousTraitCollection = previousTraitCollection else {return}
    if #available(iOS 13.0, *) {
        if previousTraitCollection.hasDifferentColorAppearance(comparedTo: traitCollection) {
            //Dark Mode
            let inputBackground = UIColor(named: "TEST1backgroundColor")
            let inputPlaceholder = UIColor(named: "TEST1placeholderColor")

            passwordBack.layer.backgroundColor = inputBackground?.cgColor
            TextField1.placeholderColor = inputPlaceholder!
            TextField2.placeholderColor = inputPlaceholder!

            TextField1.textColor = inputPlaceholder!
            TextField2.textColor = inputPlaceholder!
    }
  }
}

How can have this color change be applied when starting an already in Dark Mode?

Answer 1

CGColors don't react to dark or light mode. You don't show the declaration of passwordBack , but assuming it's a UIView or a subclass, set its backgroundColor property directly to inputBackground instead of using layer.backgroundColor

Answer 2

just used appareance for named color in assets like this. so when the app open and the dark mode is on all collors would change to their correspondin dark appareance.