How to have two variables depending on each other - arrays

I have this problem: I have two text fields, one pickerView containing an array and another text field where you need to put in a specific code depending on the selection you made in the pickerView to be able to press the button. This is what I got
var SchoolsArray = ["Option 1",
"Option 2",
"Option 3",
"Option 4"]
var code1 = "zxy" // code for Option 1
var code2 = "gbv" // code for Option 2
var code3 = "jwn" // code for Option 3
var code4 = "hqc" // code for Option 4
#IBOutlet weak var firstNameTxtField: UITextField!
#IBOutlet weak var schoolNameTxtField: UITextField!
#IBOutlet weak var schoolCodeTxtField: UITextField!
#IBAction func createAccountBtnPressed(_ sender: Any) {
if firstNameTxtField.text != nil && schoolNameTxtField.text != nil && schoolCodeTxtField.text != nil {
if schoolNameTxtField.text == "Option 1" && schoolCodeTxtField.text == code1 {
//do something here
} else {
}
} else {
}
}
As you can see this only works if you select Option 1. How can I make this work so if you select "Option 1" and in schoolCodeTxtField put in "zxy" it will proceed and if you select "Option 2" and put in "gbv" it will also proceed and so on. I hope you understand what I mean. I appreciate all help

Just like SchoolArray, you can use an array for the codes as well, and use following method:
var CodesArray = ["zxy", "gbv", "jwn", "hqc"]
#IBAction func createAccountBtnPressed(_ sender: Any) {
guard
firstNameTxtField.text != nil,
let option = schoolNameTxtField.text,
let index = SchoolsArray.index(where: { $0 == option }),
CodesArray[index] == schoolCodeTxtField.text
else {
return
}
// Code & Option both matched
}

How about use a dictionary that contains your options as keys and your codes as values. Something like this:
var SchoolsOptions = ["Option 1": "zxy",
"Option 2": "gbv",
"Option 3": "jwn",
"Option 4": "hqc"]
#IBAction func createAccountBtnPressed(_ sender: Any) {
if firstNameTxtField.text != nil && schoolNameTxtField.text != nil && schoolCodeTxtField.text != nil {
for (option, code) in SchoolsOptions {
if schoolNameTxtField.text == option && schoolCodeTxtField.text == code {
//do something here
// You only get here if the option and code match for that given school. If you need specific logic for each school you'll have to check which option you're on.
}
}
} else {
}
}

This is the cleanest solution I can think of right off the bat.
#IBOutlet weak var firstNameTxtField: UITextField!
#IBOutlet weak var schoolNameTxtField: UITextField!
#IBOutlet weak var schoolCodeTxtField: UITextField!
var codeArray: [String] = [
"zxy",
"gbv",
"jwn",
"hqc"
]
var selectedCode: String!
override func viewDidLoad() {
super.viewDidLoad()
setupPickerViewAndAssignItsDelegateAndDatasource()
guard let selectedCode = codeArray.first else { return }
self.selectedCode = selectedCode
}
public func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
return codeArray.count
}
public func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
return "Option \(row + 1)"
}
public func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
selectedCode = codeArray[row]
}
#IBAction func createAccountBtnPressed(_ sender: Any) {
if firstNameTxtField.text != nil && schoolNameTxtField.text != nil && schoolCodeTxtField.text != nil {
if schoolNameTxtField.text == selectedCode {
//do something here
} else {
}
} else {
}
}

Related

How do I loop back to the first item in an Array?

I'm sure this is very simple, but I'm using a button to go to the next item in an array and display it in a label. That much works just fine, however once the end of the array is reached the app crashes since there are no items left to display. How do I get it to go back to the first item? I've tried an If statement but had no luck.
import UIKit
class ViewController: UIViewController {
var firstQuote = 0
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
#IBOutlet weak var quotesLabel: UILabel!
var quotes = ["","Quote 1", "Quote 2", "Quote 3"]
#IBAction func nextButton(_ sender: UIButton) {
firstQuote = firstQuote + 1
quotesLabel.text = quotes[firstQuote]
}
}
This is the If Statement I tried
#IBAction func nextButton(_ sender: UIButton) {
if firstQuote < quotes.count{
firstQuote = firstQuote + 1
quotesLabel.text = quotes[firstQuote]
}
if firstQuote == quotes.count{
firstQuote = 0
quotesLabel.text = quotes[firstQuote]
}
}
A common solution is to use % (the remainder operator) to wrap firstQuote back to 0 when it is equal to quotes.count:
firstQuote = (firstQuote + 1) % quotes.count
This works for me😁
class ViewController: UIViewController {
var quotes = ["Quote 0","Quote 1", "Quote 2", "Quote 3"]
var quotesNum = 0
#IBOutlet weak var result: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
result.text = quotes[quotesNum]
}
#IBAction func incrementButton(_ sender: Any) {
if quotesNum < quotes.count {
quotesNum += 1
if quotesNum == quotes.count {
quotesNum = 0
}
result.text = quotes[quotesNum]
}
}
With This Code Beside Fixing Your Problem, You Can Understand How property observer Can Work
class ViewController: UIViewController {
var quotes = ["Quote 0","Quote 1", "Quote 2", "Quote 3"]
var quotesNum: Int = 0 {
didSet {
result.text = quotes[quotesNum]
}
}
#IBOutlet weak var result: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
result.text = quotes[quotesNum]
}
#IBAction func incrementButton(_ sender: Any) {
if quotesNum < quotes.count - 1 {
if quotesNum == quotes.count - 1 {
quotesNum = 0
} else {
quotesNum += 1
}
} else {
quotesNum = 0
}
}

how to add a column to pre-exisiting pickerview

I need a multiple component pickerview, but I need to add a new column to the far left of it. So far it only has two of the three I need. Here is the current code. I have addeded arrays, wrapped an array inside an array, added variables as a column and also changed the outputs.
import UIKit
class Country {
var cats: String
var country: String
var cities: [String]
init(country:String, cities:[String]) {
self.cats = cat
self.country = country
self.cities = cities
}
}
class ViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource {
#IBOutlet weak var pickerView: UIPickerView!
#IBOutlet weak var countryLbl: UILabel!
var countries = [Country]()
override func viewDidLoad() {
pickerView.delegate = self
pickerView.dataSource = self
cats.apppend(Cat(cat: "furry",
countries.append(Country(country: "India", cities: ["Delhi", "Ahmedabad", "Mumbai", "Pune"]))
countries.append(Country(country: "USA", cities: ["New York", "DC", "Fairfax"]))
countries.append(Country(country: "Austrailia", cities: ["Sydney", "Melbourne"]))
super.viewDidLoad()
}
func numberOfComponents(in pickerView: UIPickerView) -> Int {
return 3
}
func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
if component == 0 {
return countries.count
}
else {
let selectedCountry = pickerView.selectedRow(inComponent: 0)
return countries[selectedCountry].cities.count
}
}
func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
if component == 0 {
return countries[row].country
}
else {
let selectedCountry = pickerView.selectedRow(inComponent: 0)
return countries[selectedCountry].cities[row]
}
}
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
pickerView.reloadComponent(1)
let selectedCountry = pickerView.selectedRow(inComponent: 0)
let selectedCity = pickerView.selectedRow(inComponent: 1)
let country = countries[selectedCountry].country
let city = countries[selectedCountry].cities[selectedCity]
countryLbl.text = "Country: \(country)\nCity: \(city)"
}
}
I added the vars but do I add more brackets and then I don't know how to identify the self like why does country = country but cat can't = cat? Also, the first column I'm going to add (far left in the row) will only have 2 choices and won't effect the other choices.
Since the cats component has nothing to do with the countries, do not add cats to your Countries class (which should be a struct, by the way).
Just have a separate cats array in your view controller. And you need to update all of the picker view methods.
struct Country {
let country: String
let cities: [String]
}
class ViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource {
#IBOutlet weak var pickerView: UIPickerView!
#IBOutlet weak var countryLbl: UILabel!
let cats = ["Cat1", "Cat2"]
var countries = [Country]()
override func viewDidLoad() {
pickerView.delegate = self
pickerView.dataSource = self
countries.append(Country(country: "India", cities: ["Delhi", "Ahmedabad", "Mumbai", "Pune"]))
countries.append(Country(country: "USA", cities: ["New York", "DC", "Fairfax"]))
countries.append(Country(country: "Austrailia", cities: ["Sydney", "Melbourne"]))
super.viewDidLoad()
}
func numberOfComponents(in pickerView: UIPickerView) -> Int {
return 3
}
func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
if component == 0 {
return cats.count
} else if component == 1 {
return countries.count
} else {
let selectedCountry = pickerView.selectedRow(inComponent: 1)
return countries[selectedCountry].cities.count
}
}
func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
if component == 0 {
return cats[row]
} else if component == 1 {
return countries[row].country
} else {
let selectedCountry = pickerView.selectedRow(inComponent: 1)
return countries[selectedCountry].cities[row]
}
}
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
if component == 0 {
// do something with the new cat
} else if component == 1 || component == 2 {
if component == 1 {
pickerView.reloadComponent(2)
}
let selectedCountry = pickerView.selectedRow(inComponent: 1)
let selectedCity = pickerView.selectedRow(inComponent: 2)
let country = countries[selectedCountry].country
let city = countries[selectedCountry].cities[selectedCity]
countryLbl.text = "Country: \(country)\nCity: \(city)"
}
}
}

My loop to grab number of results within an array in swift is not working

Greetings dear fans and programmers of the Swift language. I have tried to formulate an algorithm number of times an element shows up within an array with a for loop, but it doesn't seem to be working.
My code is as follows:
else if indexPath.section == 1 {
cell = tableView.dequeueReusableCellWithIdentifier("GreenCell", forIndexPath: indexPath)
for item in theModel.userAnswer {
numOfCoincidences[item] = (numOfCoincidences[item] ?? 0) + 1
}
for (numLangs, value) in numOfCoincidences {
txtSummary = "#languages spoken: \(numLangs)"
txtSummary2 = "# of People: \(value)"
}
cell.textLabel?.text = txtSummary
cell.detailTextLabel?.text = txtSummary2
I am trying to display this information in a table Cell but it is not working. I thought that my algorithm was spot on. Any suggestions?
I'm getting the following output: I have a navigation controller in effect where I input data on one screen and it outputs the data on a table. It's a bit of a survey where I prompt the user to enter their name and the number of languages spoken. I'm using an MVC programming methodology.
so in the model, here is the code:
import Foundation
class Model {
var userName = [String]()
var userAnswer = [String]()
var userInfo = [String]()
var name:String
var answer:String
init(){
self.name = ""
self.answer = ""
}
func addUserInfo(name:String, answer:String) -> Void {
userName.append(name)
userAnswer.append(answer)
}
}
In the input screen, I have 2 text boxes that prompt for username and number of languages spoken. So on the output screen, if 2 people speak 4 languages, the output should reflect that, but it's not. If 1 person speaks 3 languages, it should display that and so on. The output is coming out completely incorrectly. Here is the for the data entry code:
import UIKit
class ViewController: UIViewController {
var model = Model()
#IBOutlet var txtName: UITextField!
#IBOutlet var lblStatus: UILabel!
#IBOutlet var txtAnswer: UITextField!
#IBAction func btnAnswer(sender: UIButton) {
model.answer = txtAnswer.text!
model.name = txtName.text!
if ((txtName.text)! == "" || (txtAnswer.text)! == "") {
lblStatus.text = "Name and answer are both required"
}else if model.userName.contains(model.name) {
lblStatus.text = "Answer already recorded for \(model.name)"
} else {
model.addUserInfo(model.name, answer: model.answer)
lblStatus.text = "Ok, \(model.name) answered \(model.answer)"
}
txtAnswer.text = ""
txtName.text = ""
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "toReesultsController" {
let vc = segue.destinationViewController as! TableViewController
vc.theModel = self.model
}
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
}
The code for the table to display the data inputted from the data entry screen is presented in a table as shown below:
import UIKit
class TableViewController: UITableViewController {
var theModel = Model()
var numOfCoincidences:[String:Int] = [:]
var txtSummary:String = ""
var txtSummary2:String = ""
var greatest:Int = 0
/* override func viewDidLoad() {
for index in 0..<theModel.userName.count {
}
}*/
override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return 3
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
if section == 0 {
return theModel.userAnswer.count
} else if section == 1 {
return theModel.userAnswer.count
} else if section == 2{
return theModel.userAnswer.count
} else {
return 0
}
}
override func tableView(tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
if section == 0 {
return "Answer Log"
} else if section == 1 {
return "Summary"
} else if section == 2 {
return "Top Answers"
} else {
return nil
}
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
var cell:UITableViewCell! = nil
if indexPath.section == 0 {
cell = tableView.dequeueReusableCellWithIdentifier("BlueCell", forIndexPath: indexPath)
cell.textLabel?.text = "\(theModel.userName[indexPath.row]):\(theModel.userAnswer[indexPath.row])"
} else if indexPath.section == 1 {
cell = tableView.dequeueReusableCellWithIdentifier("GreenCell", forIndexPath: indexPath)
for item in theModel.userAnswer {
numOfCoincidences[item] = (numOfCoincidences[item] ?? 0) + 1
}
for (numLangs, value) in numOfCoincidences {
txtSummary = "#languages spoken: \(numLangs)"
txtSummary2 = "# of People: \(value)"
}
cell.textLabel?.text = txtSummary
cell.detailTextLabel?.text = txtSummary2
} else if indexPath.section == 2 {
cell = tableView.dequeueReusableCellWithIdentifier("OrangeCell", forIndexPath: indexPath)
greatest = 0
for index in 0..<theModel.userAnswer.count {
if Int(theModel.userAnswer[index])! > greatest {
greatest = Int(theModel.userAnswer[index])!
}
}
cell.textLabel?.text = "Answer with most votes is \(greatest) languages spoken."
}
return cell
}
}
Based on what you have shared, and making some assumptions on your input this seems to do what you want.
If each item is a dictionary with the keys shown below. Then you would walk through the array and get the number of languages spoken by the person. I chose to define that as a number(Int) since that is what it really is.
This is almost the same as your original code so I have to conclude that your idea was correct, but your implementation was missing something.
Assuming this is your input:
let a = [["name":"carla", "langs" : 3], ["name":"scott", "langs" : 3], ["name":"brad", "langs" : 1], ["name":"cynthia", "langs":2]]
var numOfCoincidences = [Int: Int]()
for item in a {
let numLangs = item["langs"] as! Int
numOfCoincidences[numLangs] = (numOfCoincidences[numLangs] ?? 0) + 1
}
var txtSummary = ""
var txtSummary2 = ""
for (numLangs, value) in numOfCoincidences {
// You should also note that you are overwriting values here.
txtSummary = "#languages spoken: \(numLangs)"
txtSummary2 = "# of People: \(value)"
print(txtSummary)
print(txtSummary2)
}
numOfCoincidences
Output:
// key := number of languages spoken
// value := number of people who speak that many languages
[2: 1, 3: 2, 1: 1]
You do have a problem in your cellForRowAtIndexPath.
After you loop through all the data, you do this:
cell.textLabel?.text = txtSummary
cell.detailTextLabel?.text = txtSummary2
Therefore, every cell is going to have the last values from the loop.

getting PickerData data from a Rest WebService

i get data from a web service and my pickerData Array don't save values when i want to use it outside of the Json Parsing bloc.
here's my code
var pickerData: [String] = [String]()
var mag : String!
override func viewDidLoad() {
super.viewDidLoad()
NomMAG.alpha = 0
// \(detectionString)
let str = "http://vps43623.ovh.net/yamoinscher/api/getAllMag"
let url = NSURL(string: str)!
let task = NSURLSession.sharedSession().dataTaskWithURL(url) { (data, response, error) -> Void in
if let urlContent = data {
do {
let jsonObject = try NSJSONSerialization.JSONObjectWithData(urlContent, options: [])
if let jsonResult = jsonObject as? [String:AnyObject] {
if let Pick = jsonResult["magasin"] as? [[String:String]] {
for categorie in Pick {
self.mag = categorie["libelle"]!
self.pickerData.append(magasin)
//self.pickerData = [(self.produits[0].magasin)]
}
print(self.pickerData)
dispatch_async(dispatch_get_main_queue()) {
self.picker1.reloadInputViews()
// print(self.produits.count)
}
}
}
} catch {
print("JSON serialization failed", error)
}
} else if let connectionError = error {
print("connection error", connectionError)
}
}
task.resume()
//print(produits.count)
//pickerData = ["Item 1", "Item 2", "Item 3", "Item 4", "Item 5", "autre"]
//print(self.pickerData)
self.picker1.delegate = self
self.picker1.dataSource = self
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
// The number of columns of data
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
return 1
}
// The number of rows of data
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
return self.pickerData.count
}
// The data to return for the row and component (column) that's being passed in
func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
return self.pickerData[row]
}
func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
if pickerData[row] == "autre"
{
//print(row)
NomMAG.alpha = 1
}
else
{
//print(row.description)
NomMAG.alpha = 0
}
}
I want to get my PickerView full with the data i gained from the JsonParsing and the PickerData Array is null outside the block of code of the Json
Connect delegate and dataSource of the picker view in Interface Builder and replace viewDidLoad with
var pickerData = [String]()
override func viewDidLoad() {
super.viewDidLoad()
let str = "http://vps43623.ovh.net/yamoinscher/api/getAllMag"
let url = NSURL(string: str)!
let task = NSURLSession.sharedSession().dataTaskWithURL(url) { (data, response, error) -> Void in
if let urlContent = data {
do {
let jsonObject = try NSJSONSerialization.JSONObjectWithData(urlContent, options: [])
if let jsonResult = jsonObject as? [String:AnyObject],
magasin = jsonResult["magasin"] as? [[String:String]] {
// filter valid items, map them to an array and filter empty strings
self.pickerData = magasin.filter { $0["libelle"] != nil }.map { $0["libelle"]! }.filter { !$0.isEmpty}
}
dispatch_async(dispatch_get_main_queue()) {
self.picker1.reloadAllComponents()
}
} catch {
print("JSON serialization failed", error)
}
} else if let connectionError = error {
print("connection error", connectionError)
}
}
task.resume()
}
You have to add the NomMAG line

Swift PickerView does not show array elements

My "picker2" pickerview does not show data from "modelArray" array. When I dup the array I have data in it. But no data shown in pickerview at all.
I did everything on mind and did my research how to do it. But no success.
Any help will be highly appreciated :)
import UIKit
class MakeViewController: UIViewController, UIPickerViewDataSource, UIPickerViewDelegate {
#IBOutlet weak var txt_make: UITextField!
#IBOutlet weak var txt_model: UITextField!
var makeArray = [String]()
var modelArray = [String]()
var picker = UIPickerView()
var picker2 = UIPickerView()
var numberOfRowsMake = 0
var numberOfRowsModel = 0
override func viewDidLoad() {
super.viewDidLoad()
picker.delegate = self
picker.dataSource = self
picker2.delegate = self
picker2.dataSource = self
txt_make.inputView = picker
txt_model.inputView = picker2
txt_make.clearButtonMode = .Always
txt_model.clearButtonMode = .Always
parseJSON2()
}
func parseJSON2() {
let path : String = NSBundle.mainBundle().pathForResource("json2", ofType: "json")! as String
let jsonDATA = NSData(contentsOfFile: path) as NSData!
numberOfRowsMake = readableJSON["Cars"].count
for var i = 0; i < numberOfRowsMake; ++i {
let make = readableJSON["Cars"][i]["Manufacturer"].stringValue
makeArray.append(make)
}
}
func parseJSON3() {
let path : String = NSBundle.mainBundle().pathForResource("json2", ofType: "json")! as String
let jsonDATA = NSData(contentsOfFile: path) as NSData!
numberOfRowsMake = readableJSON["Cars"].count
for var i = 0; i < numberOfRowsMake; ++i {
let make = readableJSON["Cars"][i]["Manufacturer"].stringValue
let model = readableJSON["Cars"][i]["Model"].stringValue
print(txt_make.text)
if make == txt_make.text {
modelArray.append(model)
}
}
dump(modelArray)
}
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
return 1
}
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
if pickerView == picker {
return numberOfRowsMake
}
if pickerView == picker2 {
return numberOfRowsModel
}
return 1
}
func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
if pickerView == picker {
txt_make.text = makeArray[row]
}
if pickerView == picker2 {
self.picker2.reloadAllComponents()
parseJSON3()
txt_model.text = modelArray[row]
}
}
func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
if pickerView == picker {
return makeArray[row]
}
if pickerView == picker2 {
return modelArray[row]
}
return ""
}
}
Here is the local JSON file.
{
"Cars" :
[{
"Manufacturer": "ABARTH1",
"Model": "500, 2012 onwards",
}, {
"Manufacturer": "ABARTH1",
"Model": "500, 2012 onwards",
}, {
"Manufacturer": "ABARTH1",
"Model": "500, 2012 onwards",
}, {
"Manufacturer": "ABARTH2",
"Model": "500, 2012 onwards",
}, {
"Manufacturer": "ABARTH2",
"Model": "500, 2012 onwards",
}, {
"Manufacturer": "ABARTH2",
"Model": "500, 2012 onwards",
}
]
}

Resources