如何实现十进制键盘?

Question

注释在我的视图结构中，我有键盘，我想限制用户填写长/晚文本字段时使用。还有其他线程接近这个问题，但我不明白他们在他们的答案中引用了什么。

如何限制用户使用十进制+标点符号键盘?

//
//  ContentView.swift
//  Geo Calculator App
//  App that calculates distance between two long/lat values
//
//  Created on 9/25/21.
//
import SwiftUI
struct ContentView: View {
@State var longitude1 = ""
@State var latitude1 = ""
@State var longitude2 = ""
@State var latitude2 = ""
//self.LongLatTextField.keyboardType = UIKeyboardType.decimalPad
var body: some View {
VStack {
Spacer()

Text("Geo Calculator App")
.font(.system(size: 24, weight: .bold))
.foregroundColor(.black)

Text("Calculate distances between long/lat values")
.font(.system(size: 16, weight: .light))
.foregroundColor(.gray)


HStack {
HStack {
TextField("Longitude A", text: $longitude1)
.foregroundColor(.blue)
}.frame(height: 60)
.padding(.horizontal, 15)
.background(Color.white)
.cornerRadius(9)

HStack {
TextField("Latitude A", text: $latitude1)
.foregroundColor(.blue)
}.frame(height: 60)
.padding(.horizontal, 15)
.background(Color.white)
.cornerRadius(9)
}.frame(height: 60)
.padding(.horizontal, 15)
.cornerRadius(9)
.padding(.horizontal, 5)

HStack {
HStack {
TextField("Longitude B", text: $longitude2)
.foregroundColor(.blue)
}.frame(height: 60)
.padding(.horizontal, 15)
.background(Color.white)
.cornerRadius(9)

HStack {
TextField("Latitude B", text: $latitude2)
.foregroundColor(.blue)
}.frame(height: 60)
.padding(.horizontal, 15)
.background(Color.white)
.cornerRadius(9)
}.frame(height: 60)
.padding(.horizontal, 15)
.cornerRadius(9)
.padding(.horizontal, 5)

//Put label here to display output on button click
Spacer()

Button(action: {}) {
Text("Calculate")
.foregroundColor(.white)
.font(.system(size: 24, weight: .medium))
}.frame(maxWidth: .infinity)
.padding(.vertical, 15)
.background(Color.green.opacity(10))
.cornerRadius(30)
.padding(.horizontal, 70)

Spacer()

}.background(Color.white)
.edgesIgnoringSafeArea(.all)
}
}
//------------------------------------------------------
//Distance calculations, sources below
//geodatasource.com/developers/swift
//sisense.com/blog/latitude-longitude-distance-calculation-explained
func degreeToRadian(deg:Double) -> Double {
return deg * Double.pi / 180
}
func radianToDegree(rad:Double) -> Double {
return rad * 180 / Double.pi
}
func distance(lat1:Double, lon1:Double, lat2:Double, lon2:Double) -> Double {
let theta = lon1 - lon2
var dist = sin(degreeToRadian(deg: lat1)) * sin(degreeToRadian(deg: lat2)) + cos(degreeToRadian(deg: lat1)) * cos(degreeToRadian(deg: lat2)) * cos(degreeToRadian(deg: theta))
dist = acos(dist)
dist = radianToDegree(rad: dist)
dist = dist * 60 * 1.1515 * 1.609344

return dist
}
//------------------------------------------------------
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}

Answer 1

你可以在你的Textfield上使用键盘修饰符:

.keyboardType(.decimalPad)

文档:https://developer.apple.com/documentation/uikit/uikeyboardtype