UIPickerViewを使って値を選択する

Swift
iOS

July 5, 2020

UIPickerViewを使って値を取得するサンプルコードです。 PIPickerViewは選択肢の中から要素を選ぶときによく使いますね。今回は食べ物とドリンクとフードを選ぶアプリを作ってみました。

Picker

	import UIKit

	class ViewController: UIViewController {
	// UIPickerView.
	private lazy var myUIPicker = UIPickerView()

	// Value
	private let foodMenus: [String] = ["Hamburger","Pizza","Steak","Meatpai"]
	private let drinkMenus: [String] = ["Coke","Water","Orange juice","Tomato Juice", "Coffee"]
	private let dessertMenus: [String] = ["Ice Cream","Chocolate","Candy","LolliPop", "Donuts", ]

	override func viewDidLoad() {
	super.viewDidLoad()

	// make UIPickerView instance
	myUIPicker = UIPickerView()

	// set picker size
	myUIPicker.frame = CGRect(x: 0, y: 0, width: view.bounds.width, height: view.bounds.height)

	// set delegate
	myUIPicker.delegate = self

	// set datasources
	myUIPicker.dataSource = self

	// Set init picker position
	myUIPicker.selectRow(1, inComponent: 0, animated: true)
	myUIPicker.selectRow(2, inComponent: 1, animated: true)
	myUIPicker.selectRow(3, inComponent: 2, animated: true)

	// add view
	view.addSubview(myUIPicker)
	}
	}


	extension ViewController: UIPickerViewDelegate {
	// Called when picker moved
	func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
	print("componet: \(component)")
	print("row: \(row)")

	switch component {
	case 0:
	print("value: \(foodMenus[row])")
	case 1:
	print("value: \(drinkMenus[row])")
	case 2:
	print("value: \(dessertMenus[row])")
	default:
	print("Error")
	}
	}
	}

	extension ViewController: UIPickerViewDataSource {
	// Set number of Compenet
	func numberOfComponents(in pickerView: UIPickerView) -> Int {
	// foodMenus + drinkMenus + dessertMenus
	return 3
	}

	// Set the number of elements of Compenet
	func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {

	switch component {
	case 0:
	return foodMenus.count
	case 1:
	return drinkMenus.count
	case 2:
	return dessertMenus.count
	default:
	return 0
	}
	}

	// Set elements String
	/*
	func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
	switch component {
	case 0:
	return foodMenus[row]
	case 1:
	return drinkMenus[row]
	case 2:
	return dessertMenus[row]
	default:
	return "Error"
	}
	}
	*/

	// Set elements UIView
	func pickerView(_ pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusing view: UIView?) -> UIView {

	let cellLabel = UILabel()
	cellLabel.frame = CGRect(x: 0, y: 0, width: pickerView.rowSize(forComponent: 0).width, height: pickerView.rowSize(forComponent: 0).height)
	cellLabel.textAlignment = .center
	cellLabel.font = UIFont.boldSystemFont(ofSize: 16)
	cellLabel.backgroundColor = UIColor.orange
	cellLabel.textColor = UIColor.white

	switch component {
	case 0:
	cellLabel.text = foodMenus[row]
	case 1:
	cellLabel.text = drinkMenus[row]
	case 2:
	cellLabel.text = dessertMenus[row]
	default:
	cellLabel.text = "Error"
	}

	return cellLabel
	}
	}

view raw ViewController.swift hosted with ❤ by GitHub