How can I convert this JOptionPane result to integer value?

Question

How can I make this JOptionPane.showInputDialog return an integer value instead of a string value?

The values of the chains are in Spanish sorry in advance

I put Integer.parseInt() and it didn't work for me*

String[] Options = {
    "Mostrar la lista de ganancias de cada una de las busetas\n",
    "Mostrar la buseta que más dinero gano esa semana\n",
    "Mostrar la buseta que menos dinero gano esa semana\n",
    "Mostrar el dia que mas gana cada una de las busetas\n",
    "Aumentar las ventas que estan por debajo del promedio un 20%"
};
    
int decision = Integer.parseInt(
                                JOptionPane.showInputDialog(
                                    null,
                                    "Digite la funcion que desea usar: ",
                                    "Busetas",
                                    JOptionPane.DEFAULT_OPTION,
                                    JOptionPane.QUESTION_MESSAGE,
                                    null,
                                    Options,
                                    Options[0]));

Hi, improved readability will encourage people to answer your question by providing readers with a better experience up front. I've formatted your question for you but on your next ones, read up on stackoverflow markdown formatting. — bytehala, Feb 24 '21 at 23:10

bytehala · Accepted Answer · 2021-02-27T08:10:07.547

A good approach would be to try and understand the method you're using by checking the Javadocs

First thing that I noticed, is your code will not even compile because you have too many parameters.

JOptionPane.showInputDialog(
                            null, // parent
                            "Digite la funcion que desea usar: ", // message
                            "Busetas", // title
                            JOptionPane.DEFAULT_OPTION, // ???? What's this?
                            JOptionPane.QUESTION_MESSAGE, // message type
                            null, // icon
                            Options, // selection values
                            Options[0]); // initial selection

Next, according to the Javadocs, showInputDialog() returns type Object.

That return value is what you're passing to Integer.parseInt(String). Again, this will not compile, since parseInt expects a String. Object does not automatically cast to String. parseInt is also in the javadocs, or your IDE will tell you about this error.

If you make your code work step-by-step to try and understand what is happening, you'll see that showInputDialog returns the full String that the user selected from the dropdown. These come from your Options array. None of those can be directly translated to int:

// Use small first letter in variable names. This is java convention and will help readers of your code be less confused.
String[] options = {
    "Mostrar la lista de ganancias de cada una de las busetas\n",
    "Mostrar la buseta que más dinero gano esa semana\n",
    "Mostrar la buseta que menos dinero gano esa semana\n",
    "Mostrar el dia que mas gana cada una de las busetas\n",
    "Aumentar las ventas que estan por debajo del promedio un 20%"
};

Object selection = JOptionPane.showInputDialog(
                                    null,
                                    "Digite la funcion que desea usar: ",
                                    "Busetas",
                                    // JOptionPane.DEFAULT_OPTION, // Removed this to make it work
                                    JOptionPane.QUESTION_MESSAGE,
                                    null,
                                    options,
                                    options[0]);

System.out.println(selection); // This prints for example: Mostrar la lista de ganancias de cada una de las busetas
    
// Therefore below line will be like Integer.parseInt("Mostrar la lista...");
int decision = Integer.parseInt(selection);

So you can see now why Integer.parseInt() did not work.

My suggestion is look up how to find the index of a String within a String array: How to find index of STRING array in Java from a given value?

TLDR: Your code doesn't compile. Refer to the Javadocs. Simplify your problem by taking smaller steps.

score 0 · Answer 2 · answered Feb 25 '21 at 21:10

Thanks for the help. I attach the solution and explanation of the change I made in the code in case someone needs it

String[] options = {
        "Mostrar la lista de ganancias de cada una de las busetas", 
        "Mostrar la buseta que más dinero gano esa semana", 
        "Mostrar la buseta que menos dinero gano esa semana",
        "Mostrar el dia que mas gana cada una de las busetas",
        "Aumentar las ventas que estan por debajo del promedio un 20%",
        "Salir"};

Object selection = JOptionPane.showInputDialog(
            null, 
            "Seleccione una de las opciones disponibles", 
            "Busetas",
            JOptionPane.QUESTION_MESSAGE,
            null,
            options,
            options[0]);
    
decision = Arrays.asList(options).indexOf(selection);

I made use of the java.util.Arrays library after this, I take the asList () method that returns us a list of fixed size backed by the specified array, in this case, it is the options array then I use the .indexOF () method to return an integer value depending on the selection and assign it to the decision variable

Congratulations on learning markup and following Java naming conventions! — bytehala, Feb 26 '21 at 23:33

How can I convert this JOptionPane result to integer value?

2 Answers2