SwiftUI用sheet弹出UIColorPickerViewController无法下拉关闭如何解决

你的问题由两个错误导致：

• sheet调用语法错误，你把弹窗视图内容放在了onDismiss回调参数中，该参数是弹窗关闭后才执行的逻辑，不是弹窗内容
• UIColorPickerViewController默认将isModalInPresentation属性设置为true，主动禁用了下拉关闭手势

完整修改方案 #

1. 修正ColorPickerView实现，手动开启下拉关闭权限，添加代理处理交互逻辑

import SwiftUI
import UIKit

struct ColorPickerView: UIViewControllerRepresentable {
    @Binding var selectedColor: UIColor
    @Binding var isPresented: Bool
    
    func makeCoordinator() -> Coordinator {
        Coordinator(parent: self)
    }
    
    func makeUIViewController(context: Context) -> UIColorPickerViewController {
        let colorPicker = UIColorPickerViewController()
        colorPicker.selectedColor = selectedColor
        // 核心配置：允许下拉关闭
        colorPicker.isModalInPresentation = false
        colorPicker.delegate = context.coordinator
        return colorPicker
    }
    
    func updateUIViewController(_ uiViewController: UIColorPickerViewController, context: Context) {
        uiViewController.selectedColor = selectedColor
    }
    
    class Coordinator: NSObject, UIColorPickerViewControllerDelegate {
        let parent: ColorPickerView
        
        init(parent: ColorPickerView) {
            self.parent = parent
        }
        
        func colorPickerViewControllerDidSelectColor(_ viewController: UIColorPickerViewController) {
            parent.selectedColor = viewController.selectedColor
        }
        
        func colorPickerViewControllerDidFinish(_ viewController: UIColorPickerViewController) {
            parent.isPresented = false
        }
    }
}

2. 修正sheet调用写法，把弹窗内容放到正确的参数位置

// 所在视图需要提前定义两个状态变量
@State private var selectedColor = UIColor.white
@State private var showSheet = false

// sheet调用代码
.sheet(isPresented: $showSheet) {
    // 弹窗内容放这里
    ColorPickerView(selectedColor: $selectedColor, isPresented: $showSheet)
    // 可选配置：适配半高弹窗交互，iOS15+支持
    .presentationDetents([.medium, .large])
} onDismiss: {
    // 弹窗关闭后的逻辑放这里，比如保存颜色
    print("最终选中颜色：\(selectedColor)")
}

修改后即可正常使用下拉手势关闭颜色选择弹窗，同时颜色选择、点击完成按钮的交互也会正常生效。

内容的提问来源于stack exchange，提问作者user2802154