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Android

Posted by Michael Narvaez
Michael Narvaez
4,182 Points

What is the best practice method to take user input (numbers) calculate with the input and display it back to the user.

Hello, Im building my first original app, which is a very simple tax calculating app that takes user input as numbers and adds the tax value then returns the result to the user. Im having trouble converting the input data into a double or int so that I can return the result. Thanks,

1 Answer

JT Keller
JT Keller
12,731 Points
JT Keller
JT Keller
12,731 Points

Hi Michael,

It might be helpful to others if you can post the code that you have so that the community can take a look and offer helpful hints and advice.

You don't need to return a numeric value, you just need numerics to perform your calculations and then you can convert that to a String so that you can update/set the text for your app. I did something very similar here: Discount Calculator Example.

    //Calculates and returns a String representation of how much the user
    //should pay
    public String calcPay() {
        double saved = userInput - (userInput * discount);
        formatter.format(saved);
        String youSaved = String.valueOf(formatter.format(saved));
        return "$" + youSaved;
    }
    //Calculates and returns a String representation of how much the user
    //saved

    public String calcSaved() {
        double amount = userInput * discount;
        String youPay = String.valueOf(formatter.format(amount));
        return "$" + youPay;
    }

I hope this helps :)