How to only allow positive numbers in an EditText

You should use the attr of EditText:

android:digits="0123456789."
android:inputType="number"

http://developer.android.com/reference/android/widget/TextView.html#attr_android:digits

So user will be able enter only digits without minus.

UPDATED: Something like that, to prevent first sign from 0:

    editText.addTextChangedListener(new TextWatcher() {
        @Override
        public void afterTextChanged(Editable edt) {
            if (edt.length() == 1 && edt.toString().equals("0"))
                editText.setText("");
        }

        // ...
    });

For each EditText, you have to do this :

if (Integer.parseInt(et1local.getText().toString()) > 0)

Do a function to ensure it's a number

private boolean isPositive(EditText et)
{
    try
    {
        return Integer.parseInt(et.getText().toString()) > 0;
    }
    catch (Exception e)
    {
        return false;
    }
}

Use it like that :

if (et1local.getText().toString().length() == 0 || !isPositive(et1local)
 || et2local.getText().toString().length() == 0 || !isPositive(et2local)
// [...]