LongPressShrinkModifier

LongPressShrinkModifier.swift

import SwiftUI

extension View {
    /// Adds the `LongPressShrinkModifier` modifier.
    /// A modifier that adds a LongPressGesture action, that shrinks the view while it's being tapped.
    /// - Parameters:
    ///   - animationDuration: The shrink animation duration. `Default = 0.3`.
    ///   - shrinkScale: The scale value for when the view is pressed. `Default = 0.85`.
    ///   - defaultScale: The scale value for when the view is not pressed: `Default = 1.0`.
    ///   - minimumLongPressDuration: The minimum long press duration. `Default = 0.5`.
    ///   - action: The action to execute.
    /// - Returns: The original view, with the modifier applied.
    func shrinkOnLongPress(
        animationDuration: TimeInterval = 0.3,
        shrinkScale: CGFloat = 0.85,
        defaultScale: CGFloat = 1,
        minimumLongPressDuration: TimeInterval = 0.5,
        action: @escaping () -> Void
    ) -> some View {
        modifier(
            LongPressShrinkModifier(
                animationDuration: animationDuration,
                shrinkScale: shrinkScale,
                defaultScale: defaultScale,
                minimumLongPressDuration: minimumLongPressDuration,
                action: action
            )
        )
    }
}

struct LongPressShrinkModifier: ViewModifier {
    @State private var isTouched = false
    private var animationDuration: TimeInterval
    private var shrinkScale: CGFloat
    private var defaultScale: CGFloat
    private var minimumLongPressDuration: TimeInterval
    private var action: () -> Void

    init(
        animationDuration: TimeInterval,
        shrinkScale: CGFloat,
        defaultScale: CGFloat,
        minimumLongPressDuration: TimeInterval,
        action: @escaping () -> Void
    ) {
        self.animationDuration = animationDuration
        self.shrinkScale = shrinkScale
        self.defaultScale = defaultScale
        self.minimumLongPressDuration = minimumLongPressDuration
        self.action = action
    }

    func body(content: Content) -> some View {
        content
            .scaleEffect(isTouched ? shrinkScale : defaultScale, anchor: .center)
            .animation(.easeInOut(duration: animationDuration), value: isTouched)
            .onLongPressGesture(
                minimumDuration: minimumLongPressDuration,
                pressing: { pressing in
                    isTouched = pressing
                }, perform: {
                    action()
                }
            )
    }
}