SwiftUI

闲时

SafeArea

// 只扩展到底部
.ignoresSafeArea(edges: .bottom)

// 扩展到顶部和底部
.ignoresSafeArea(edges: [.bottom, .trailing])

// 横向扩展
.ignoresSafeArea(edges:.horizontal)

使用Core Data存储自定义类的数组

Store an Array of Custom Data Types in Core Data With Transformable and NSSecureCoding

【iOS】CoreData保存自定义数据(swift)

首先NSObject、NSSecureCoding

然后Transformable

// 为了能让CoreData能够自己解析编码[Tag]，首先上面的Tag需要先conform to：NSSexureCoding和NSObject
class TagAttributeTransformer: NSSecureUnarchiveFromDataTransformer {
    override static var allowedTopLevelClasses: [AnyClass] {
        [NSArray.self, Tag.self]
    }
    
    static func register() {
        let className = String(describing: TagAttributeTransformer.self)
        let name = NSValueTransformerName(className)
        let transformer = TagAttributeTransformer()
        
        ValueTransformer.setValueTransformer(transformer, forName: name)
    }
}

Core Data Relationship in Swift 5— made simple, singer and her songs

From Hex to Color and Back in SwiftUI

有关，我在存储我的tags的时候，用的transformable存储的[Tag]数组，但是更改数组里面的一个Tag的名字或者颜色在存储的时候是无效的，原因如下，所以我后面直接用one to many这个relationship了。

Swift: How to update transformable objects

Transformable attributes are a immutable type, therefore cannot be changed. The only way of changing them is by creating a new object and saving it again to core data.

To solve this I deleted the property cartItemAttribute from my xcdatamodel which holds both a product and a quantity as one transformable attribute. I replaced it with a product attribute of type transformable and a quantity attribute of type Int and everything works fine now.

one to many之后使用自动生成的addToTags这些会有问题，所以自己写

Saving CoreData to-many relationships in Swift

Setting an NSManagedObject relationship in Swift

// MARK: Generated accessors for tags
extension PersonInfo {
    public var wrappedTags: [CloudTag] {
        let set = tags as? Set<CloudTag> ?? []
        return set.sorted {
            return $0.wrappedcreatdDate < $1.wrappedcreatdDate
        }
    }
    
    public func getTag(from tagID: UUID) -> CloudTag? {
        return self.wrappedTags.first { $0.wrappedID ==  tagID}
    }
    
//    @objc(addTagsObject:)
//    @NSManaged public func addToTags(_ value: CloudTag)
//
//    @objc(removeTagsObject:)
//    @NSManaged public func removeFromTags(_ value: CloudTag)
//
//    @objc(addTags:)
//    @NSManaged public func addToTags(_ values: NSSet)
//
//    @objc(removeTags:)
//    @NSManaged public func removeFromTags(_ values: NSSet)
    
    func addPersonInfoTag(value: CloudTag) {
        let items = self.mutableSetValue(forKey: "tags")
        items.add(value)
    }

    func removePersonInfoTag(value: CloudTag) {
        let items = self.mutableSetValue(forKey: "tags");
        items.remove(value)
    }
}

haptic feedback

1、2、3

UINotificationFeedbackGenerator

UIImpactFeedbackGenerator

UISelectionFeedbackGenerator

switch i {
  case 1:
  let generator = UINotificationFeedbackGenerator()
  generator.notificationOccurred(.error)

  case 2:
  let generator = UINotificationFeedbackGenerator()
  generator.notificationOccurred(.success)

  case 3:
  let generator = UINotificationFeedbackGenerator()
  generator.notificationOccurred(.warning)

  case 4:
  let generator = UIImpactFeedbackGenerator(style: .light)
  generator.impactOccurred()

  case 5:
  let generator = UIImpactFeedbackGenerator(style: .medium)
  generator.impactOccurred()

  case 6:
  let generator = UIImpactFeedbackGenerator(style: .heavy)
  generator.impactOccurred()

  default:
  let generator = UISelectionFeedbackGenerator()
  generator.selectionChanged()
  i = 0
}

4、CoreHaptics

import CoreHaptics

func complexSuccess() {
    // make sure that the device supports haptics
    guard CHHapticEngine.capabilitiesForHardware().supportsHaptics else { return }
    var events = [CHHapticEvent]()

    // create one intense, sharp tap
    let intensity = CHHapticEventParameter(parameterID: .hapticIntensity, value: 1)
    let sharpness = CHHapticEventParameter(parameterID: .hapticSharpness, value: 1)
    let event = CHHapticEvent(eventType: .hapticTransient, parameters: [intensity, sharpness], relativeTime: 0)
    events.append(event)

    // convert those events into a pattern and play it immediately
    do {
        let pattern = try CHHapticPattern(events: events, parameters: [])
        let player = try engine?.makePlayer(with: pattern)
        try player?.start(atTime: 0)
    } catch {
        print("Failed to play pattern: \(error.localizedDescription).")
    }
}