Android :: EditText.getText - Not Working

I am simple sudoku app. My main.xml has 81 EditText and 2 buttons as shown below.

CODE:................

In my activity class, I have grouped all these 81 EditTexts into one 2- dimensional array as shown below.

CODE:....................

Now when I try to do a simple getText() method on textArray[][], it gives me a runtime error but setText() method works fine on textArray[] [] textArray[i][j].getText().toString()