turning 3 leds on/off using serial port - arduino

Question

I am trying to write a program that will do the following :
Write code so that if 1 then enter pressed or send clicked, and then 1 again and enter pressed or send clicked causes LED one to turn on, if ‘1’ ‘0’ is entered in a similar way then LED 1 turns off, and so on for LEDs two and three, ie: ‘2’ ‘1’ turns on LED 2, ‘3’ ’0’ turns off LED 3.
So far here is my code:
int incomingVal;
int ledPin = 16;
int ledPin2 = 15;
int ledPin3 = 14;
void setup()
{
Serial.begin(9600); // opens serial port, sets data rate to 9600 bps
Serial.println("starting");
pinMode(ledPin,OUTPUT);
pinMode(ledPin2,OUTPUT);
pinMode(ledPin3,OUTPUT);
}
void checkForRecvdChar ();
void loop()
{
if (Serial.available() > 0 ) //then chars are in the serial buffer
{
incomingVal = Serial.parseInt();
Serial.print("You entered: ");
Serial.println(incomingVal);
if (incomingVal == 10);//turns off led 1
{
digitalWrite(ledPin, LOW);
}
if (incomingVal == 11);//turns on led 1
{
digitalWrite(ledPin, HIGH);
}
if (incomingVal == 20);//turns off led 2
{
digitalWrite(ledPin2, LOW);
}
if (incomingVal == 21);//turns on led 2
{
digitalWrite(ledPin2, HIGH);
}
if (incomingVal == 30);//turns off led 3
{
digitalWrite(ledPin3, LOW);
}
if (incomingVal == 31);//turns on led 3
{
digitalWrite(ledPin3, HIGH);
}
}
}
Right now it turns all LEDs on no matter what combination I enter

Answer 1

you've got semi colons after your if statements, which terminates the if statement. So all your intended if blocks get executed.
for example...
if (incomingVal == 31);//turns on led 3
{
digitalWrite(ledPin3, HIGH);
}
needs to be
if (incomingVal == 31)
{
digitalWrite(ledPin3, HIGH);
}

Answer 2

Ok So First It Will Better To Use Switch Case in this Case:
1. You Can Just Use The Same Number To Turn The Led ON and OFF
Example:
case 1:
{
if(wFlag == false)
{
digitalWrite(LED, HIGH);
wFlag = true;
Serial.println("LED is ON");
}
else if (wFlag == true)
{
digitalWrite(LED, LOW);
wFlag = false;
Serial.println("LED is OFF");
}
break;
}
2. The Way You Do It, Your Problem Is Serial Read Gets Only Byte after Byte
So When You Press 1 or 11 It Sees 1 Because It is The First one "1" and Then Do Your If
Statment.
You Can Fix it Like This:
while (Serial.available())
{
IncomingData = Serial.parseInt();
Temp += String(IncomingData); //Temp String Var
}
DataIN = Temp.toInt(); //DataIN int Var
Temp =""; // Rest The Temp String
Switch(DataIN) // Or if(DataIN == 1)
{
}