Try this..
Use contains
like below
else if(txtLdays.getText().toString().trim().contains(".."))
{
txtLdays.requestFocus();
txtLdays.setError("Double decimal ?");
return false;
}
EDIT
String to double
double result = Double.parseDouble(txtLdays.getText().toString().trim());
int to double
double result = (double) 12;
If user enters 12.
then check endsWith
double result;
if(txtLdays.getText().toString().trim().endsWith("."))
result = Double.parseDouble(txtLdays.getText().toString().trim().replace("\\.", ""))