首页 > 解决方案 > 使用 Swift UI 更改文本字段时动画颜色变化

问题描述

如果选择了具有相应行的文本字段,我创建了一个 OTP 页面,该页面会更改下划线的颜色。颜色会正确变化,但我想添加动画,线条的颜色会像动画一样缓慢变化。我附上了一个关于预期和当前行为的示例。

我试图在动画中添加轻松,但在关闭数字和文本时出现问题。它们都不会同时下降或过渡。在录音中,当我点击完成时,线条稍微落后了一点。

PS。我只能使用 Xcode 12.3 版本。

import SwiftUI

@available(iOS 13.0, *)
class OTPViewModel: ObservableObject {
    
    @Published var otpField = "" {
        didSet {
            isNextTypedArr = Array(repeating: false, count: 6)
            guard otpField.count <= 6,
                  otpField.last?.isNumber ?? true else {
                otpField = oldValue
                return
            }
            if otpField.count < 6 {
                isNextTypedArr[otpField.count] = true
            }
        }
    }
    var otp1: String {
        guard otpField.count >= 1 else {
            return ""
        }
        return String(Array(otpField)[0])
    }
    var otp2: String {
        guard otpField.count >= 2 else {
            return ""
        }
        return String(Array(otpField)[1])
    }
    var otp3: String {
        guard otpField.count >= 3 else {
            return ""
        }
        return String(Array(otpField)[2])
    }
    var otp4: String {
        guard otpField.count >= 4 else {
            return ""
        }
        return String(Array(otpField)[3])
    }
    
    var otp5: String {
        guard otpField.count >= 5 else {
            return ""
        }
        return String(Array(otpField)[4])
    }
    
    var otp6: String {
        guard otpField.count >= 6 else {
            return ""
        }
        return String(Array(otpField)[5])
    }
    
    @Published var isNextTypedArr = Array(repeating: false, count: 6)
    
    @Published var borderColor: Color = .black
    
    @Published var isEditing = false {
        didSet {
            isNextTypedArr = Array(repeating: false, count: 6)
            if isEditing && otpField.count < 6 {
                isNextTypedArr[otpField.count] = true
            }
        }
    }
}

@available(iOS 13.0, *)
struct CXLRPOTPView: View {
    
    @ObservedObject var viewModel = OTPViewModel()
    
    let textBoxWidth = UIScreen.main.bounds.width / 8
    let textBoxHeight = UIScreen.main.bounds.width / 8
    let spaceBetweenLines: CGFloat = 16
    let paddingOfBox: CGFloat = 1
    var textFieldOriginalWidth: CGFloat {
        (textBoxWidth*6)+(spaceBetweenLines*3)+((paddingOfBox*2)*3)
    }
    
    var body: some View {
        VStack {
            ZStack {
                HStack (spacing: spaceBetweenLines){
                    otpText(text: viewModel.otp1, isNextTyped: $viewModel.isNextTypedArr[0])
                    otpText(text: viewModel.otp2, isNextTyped: $viewModel.isNextTypedArr[1])
                    otpText(text: viewModel.otp3, isNextTyped: $viewModel.isNextTypedArr[2])
                    otpText(text: viewModel.otp4, isNextTyped: $viewModel.isNextTypedArr[3])
                    otpText(text: viewModel.otp5, isNextTyped: $viewModel.isNextTypedArr[4])
                    otpText(text: viewModel.otp6, isNextTyped: $viewModel.isNextTypedArr[5])
                }
                
                TextField("", text: $viewModel.otpField) { isEditing in
                    viewModel.isEditing = isEditing
                }
                .frame(width: viewModel.isEditing ? 0 : textFieldOriginalWidth, height: textBoxHeight)
                .textContentType(.oneTimeCode)
                .foregroundColor(.clear)
                .accentColor(.clear)
                .background(Color.clear)
                .keyboardType(.numberPad)
            }
        }
    }
    
    @available(iOS 13.0, *)
    private func otpText(text: String, isNextTyped: Binding<Bool>) -> some View {
        return Text(text)
            .font(Font.custom("GTWalsheim-Regular", size: 34))
            .frame(width: textBoxWidth, height: textBoxHeight)
            .background(VStack{
                Spacer()
                RoundedRectangle(cornerRadius: 1)
                    .frame(height: 2)
                    .foregroundColor(isNextTyped.wrappedValue ? Color(hex: "#367878") : Color(hex: "#BCBEC0"))
                    .animation(.easeIn) //this made the text bounced.
            })
            .padding(paddingOfBox)
    }
}

标签: iosswiftanimationswiftuicolors

解决方案


问题是您没有正确偏移颜色,因此它默认为褪色。绿色下划线是一个单独的组件,它会根据指针的位置而变化。


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