Hey i have a assignment in which i have a digital billboard its almost complete but i just have 1 line that is stopping my program from doing what its suppose to do.

Im suppose to have a program that can display block letters when the user enters a word or character. the program reads ASCII code from a file.

This is the last step i need to do

*Rewrite the writeLetter method to use this idea instead of using a switch
statement, and then call writeArray, passing in the correct sheet of the letter
array*. i have erased the switch statement and put the next step but i just need the call from writeLetter to writeArray.

i sumbitted the program so far for feedback and got this comment back.
You are missing a critical call (the one that draws a letter) in your writeText method.

Can anyone help me the code is below

import java.util.Scanner; //needed for Scanner
import billboard.BillboardInterface;
import billboard.DigitalBillboardFrame;
import java.io.File;
import java.io.FileNotFoundException;

public class FilesBillboard 
{

    // initial size of the display in pixels
    static final int WINDOW_WIDTH = 300;
    static final int WINDOW_HEIGHT = 120;
    // size of the grid for the digital billboard
    static final int BB_WIDTH = 50;
    static final int BB_HEIGHT = 30;

    // we will make letters 5 cells wide and 12 high
    static final int LETTER_WIDTH = 8;
    static final int LETTER_HEIGHT = 12;
    // and leave a 1 cell gap between letters
    static final int GAP = 0;

    //number of characters in file
    static final int NUM_LETTERS = 95;

    //name for the textfile
    static final String LETTER_PATH = "letters.txt";

    // the top left of the first letter in the word will be 2 cells from the left and 1 down
    static final int START_X = 2;
    static final int START_Y = 1;

    private static final int[][] _s =
        {
            {0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0},
            {0, 1, 1, 1, 1},
            {1, 0, 0, 0, 0},
            {1, 0, 0, 0, 0},
            {0, 1, 1, 1, 0},
            {0, 0, 0, 0, 1},
            {0, 0, 0, 0, 1},
            {1, 1, 1, 1, 0},
            {0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0}
        };

    private static final int[][] _p =
        {
            {0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0},
            {1, 1, 1, 1, 0},
            {1, 0, 0, 0, 1},
            {1, 0, 0, 0, 1},
            {1, 0, 0, 0, 1},
            {1, 0, 0, 0, 1},
            {1, 0, 0, 0, 1},
            {1, 1, 1, 1, 0},
            {1, 0, 0, 0, 0},
            {1, 0, 0, 0, 0},
            {1, 0, 0, 0, 0}

        };

    private static final int[][] _a = 
        {
            {0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0},
            {0, 1, 1, 1, 0},
            {1, 0, 0, 1, 0},
            {1, 0, 0, 1, 0},
            {1, 0, 0, 1, 0},
            {1, 0, 0, 1, 0},
            {1, 0, 0, 1, 0},
            {0, 1, 1, 0, 1},
            {0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0}
        };

    private static final int[][] _r = 
        {
            {0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0},
            {1, 0, 1, 1, 0},
            {0, 1, 0, 0, 1},
            {0, 1, 0, 0, 0},
            {0, 1, 0, 0, 0},
            {0, 1, 0, 0, 0},
            {0, 1, 0, 0, 0},
            {0, 1, 0, 0, 0},
            {0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0}
        };

    private static final int[][] _e = 
        {
            {0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0},
            {0, 1, 1, 1, 0},
            {1, 0, 0, 0, 1},
            {1, 0, 0, 0, 1},
            {1, 1, 1, 1, 0},
            {1, 0, 0, 0, 0},
            {1, 0, 0, 0, 1},
            {0, 1, 1, 1, 0},
            {0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0}
        };

    public static void main(String[] args)
    {
        //Call on readletters
        try
        { 
            readLetters(); //method that throws exception
        }
        catch (FileNotFoundException fnfe)
        {
            //print error message
            return; //leave
        }

        // create a billboard
        BillboardInterface billboard = new DigitalBillboardFrame(
                "SCSS",
                WINDOW_WIDTH, WINDOW_HEIGHT,
                BB_WIDTH, BB_HEIGHT);

        // first make sure the display is blank
        billboard.allOff();

        //forever

        for(;;)
        {
            //get a message from the user
            String word;
            Scanner userInput = new Scanner (System.in); //Create Scanner Object
            System.out.print("Enter a 5 letter word using the letters s, p, a, r, e! \n>>> ");
            word = userInput.nextLine();
            billboard.allOff();

            //for each letter in the message
            //for each letter in the message
            int x = START_X; //keep track of where each letter should go
            int y = START_Y;

            //display the letter
            writeText(billboard, x, y, word);

        }
    }
    private static void writeLetter(BillboardInterface billboard, int x, int y, char c) // Displaying appropriate letters
    { 
        int code =(int)(c - ' ');

    }
    private static void writeText(BillboardInterface billboard, int x, int y, String text) // Getting word from user
    {
        int length = text.length(); // Defining length

        for(int i = 0; i < 5 && i < length; i++)
        {
            //display the i_th letter
            char charAt = text.charAt(i);

            x += LETTER_WIDTH + GAP;


            billboard.redisplay(0);
        }
    }

    private static void writeArray(BillboardInterface billboard, int x, int y, int[][] pixels) //method for array
    {
        for(int row = 0; row < pixels.length; row++)
        {
            for(int col = 0; col < pixels[row].length; col ++)
            {

                if (pixels[row][col] == 1) //checking if the pixel is a 1

                { 
                    billboard.turnOn(x+col, y+row); //using a turnOn to turn on the grid at a specific pixel
                }

            }
        }
    }

    //declare a static field for the 3 dimensional array
    private static int [][][] letters;

    //read from file and display in array
    private static void readLetters() throws FileNotFoundException
    {
        //created the letters array
        letters = new int [NUM_LETTERS][LETTER_HEIGHT][LETTER_WIDTH];

        //Using scanner object to open file
        File letterFile = new File(LETTER_PATH);
        Scanner input = new Scanner(letterFile);

        //Nested Loops  to read data from file
        for (int i = 0; i < NUM_LETTERS; ++i){ 
            for (int j = 0; j < LETTER_HEIGHT; ++j){
                for (int k = 0; k < LETTER_WIDTH; ++k) {
                    letters[i][j][k] = input.nextInt(); 

                }
            }
        }

    }

}

You are missing a critical call (the one that draws a letter) in your writeText method.

That says it all really. I looked around lines 165-173 and I see you setting up array indexes etc, but you never call any method that will display/draw anything.

yes i know because im really confused on how to call this particular method

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