LED's with switch not working

Using Arduino LEDs and Multiplexing
#1

so i just got my arduino like two days ago and i am trying to make a two LED's switch were if is no current going to pin 4 and LED will be flashing but if it is high anouther led turns on instead and does not flash. i typed up the could and it gives me no errors but when i plug it all in nothing happens :blush:

here is my code

void setup() {
  pinMode(12, OUTPUT);
  pinMode(9, OUTPUT);
  pinMode(4, INPUT);
  pinMode(7, OUTPUT);

}
int brightness = 0;
int fadeAmount = 5;

void loop ()
{

  digitalWrite(7, HIGH);
  
  if( 4 == HIGH)
  {
     analogWrite(9, brightness);    

     brightness = brightness + fadeAmount;

     if (brightness == 0 || brightness == 255) {
        fadeAmount = -fadeAmount ; 
        }     
        delay(30);                            
  }
    if(4 == LOW)
     { 
       digitalWrite(12, HIGH);
     }
}
#2

You have to digitalRead your pin 4.

Place your int declarations before the void setup ()

#3

Also, you might want to look into the current state of the LED's and change them if required.

For example, Pin 12 is made HIGH if Pin 4 is LOW but it will then stay HIGH forever although I suspect the intention is that it will go LOW if if Pin 4 subsequently changes to HIGH.

#4

And you do have a resistor in seriese with each LED don't you.

#5

thanks a lot and yes i have resistors with the LEDS

#6 
if( 4 == HIGH)

This doesn't seem likely.

#7