Question

Hi I’m not sure if this is a problem with Eclipse or Java but recently my code has stopped working. I only changed things like assigning new variables to store things. My program takes a multi-dimensional string array and should return a new array trimmed of nulls.

public void makebuttons(final int n, String equals) {
    //does lots of widget functions and id assignments
    String[] items=getArray(Integer.parseInt(data.equnits.substring(n*3, n*3+1)));
    unitvalues[n]=Integer.parseInt(data.equnits.substring(n*3, n*3+1));
    ArrayAdapter aa = new ArrayAdapter(this,android.R.layout.simple_spinner_item, items);
    //does more code
}
public static String[] getArray(int selection) {
    String[] result;//stores the new array
    int x=0,j=0 ,ulength = data.units[0].length;//ints used
    String temp="";
    while(j < ulength && temp!=null) {
        temp= data.units[selection][j][0];    //find the actual array length
        j++;
    }
    if(j==ulength)j--;
    result = new String[j+1];//initalise array from check
    for(x=0; x<=j; x++) { //add data to array
        result[x]=data.units[selection][x][0];
    }
    return result;//return corrected array
}

Integer.parseInt and Integer.valueOf give value of 0 each time for a string like “01,02,03,04” data.equnits stores the string to be converted to integer by checking 2 digits only to select from a large 3 dimensional array. Since its a 3 dimensional array some nulls are present

Null check for the String doesnt seem to work since the while loop doesnt seem to detect it and it ends up being in the array that gets passed into the array adapter for spinner causing NullPointerException while scrolling.

Restarting eclipse doesn’t help.

Answer 1

I can’t help with your first problem without more information, but this seems to be the issue with your second:

The function substring is inclusive of the first parameter and exclusive of the second. Since you are only adding 1 to the n*3, you only get one character.

Try using:

substring(n*3, n*3+2)

Edit:

Adding the updated code from my comment above:

while(j < ulength && temp != null && !temp.isEmpty())
{
   temp = data.units[selection][j];
   j++;
}