CODEWITHSUNDEEP
iosswiftuitextfield
B. Deaton
B. Deaton

Reputation: 55

I need help formatting decimal places in a Text Field using Swift 4

I have a few calculations that perform after I select the "Calculate" function. The results vary depending on the values entered. I need to limit the results to 2 decimal places. I have tried numerous options with no luck. Any help here would be appreciated. Again, I am using Swift 4 in an iOS app.

Here is a bit of the code I am using:

@IBOutlet weak var f0TextField: UITextField!

@IBAction func calculateButton(_ sender: Any) {
    f0TextField.text = "\(((Double(f1TextField.text ?? "%.2f") ?? 0.0) + (Double(f2TextField.text ?? "%.2f") ?? 0.0))/2)"

I have 6 more "textfields" that I have to apply this to also.

Upvotes: 0

Views: 1322

Answers (4)

iOS Geek
iOS Geek

Reputation: 4855

Try using common Extension for Double 

extension Double
{
    //MARK: Rounds the double to decimal places value
    /**
     This func return Double to rounded Place
     - paramter places : Number of places to be rounded
     */
    func rounded(toPlaces places:Int) -> Double
    {
        let divisor = pow(10.0, Double(places))
        return (self * divisor).rounded() / divisor
    }
}

Usgae - Double(newValue).rounded(toPlaces: 0)

Upvotes: 0

rmaddy
rmaddy

Reputation: 318774

You need to break up that code. First get the text of the two text fields. Then convert the two text values to Double. Then add the two numbers. Then convert the sum to a string formatted as desired.

Here's one way:

if let val1 = Double(f1TextField.text ?? "0"), let val2 = Double(f12TextField.text ?? "0") {
    let sum = val1 + val2
    f0TextField.text = String(format: "%.2f", sum)
}

But you really should use NumberFormatter to show the result in a proper locale sensitive way. And most likely you need it to parse the user entered numbers as well.

You probably should also create a function that takes any two text fields and returns a String that you can then set on the appropriate text field.

Upvotes: 0

William Loke
William Loke

Reputation: 377

Credits to @Sebastian, used his suggested code and it works. You can try if it works for you

First have this extension

extension Double {
    /// Rounds the double to decimal places value
    func rounded(toPlaces places:Int) -> Double {
    let divisor = pow(10.0, Double(places))
    return (self * divisor).rounded() / divisor
}}

then 

let x = Double(textField.text).rounded(toPlaces: 2)
print(x) // to see if it works

Upvotes: 0

Amrit Trivedi
Amrit Trivedi

Reputation: 1270

If you want final answer in 2 decimal places than you should apply it to final result like below.

let currentRatio = Double (rxCurrentTextField.text!)! / Double (txCurrentTextField.text!)!
railRatioLabelField.text! = String(format: "%.2f", currentRatio)

Example

let myDouble = 3.141
let doubleStr = String(format: "%.2f", myDouble) // "3.14"

Upvotes: 1

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