I am trying to get my program to exit a loop based on an event such as mouse event below; however, it doesn't seem to want to stop looping even with a delay. Any ideas how to get this loop to stop based on an event?

Thanks

void mousePressed() {
 
  stop = true;
 
}

void draw() {
   
 ArrayList rxdata = new ArrayList();

 while (myPort.available() > 0) { //principal loop
 
   String inBuffer = myPort.readStringUntil(',');  
   
   //data
    if (inBuffer != null  && stop ==false) {
                  
        rxdata.add(inBuffer);
      //  int size = rxdata.size();  // 2
        println(rxdata.get(count));   // a
   
      i = i +1;
     
      delay(200);
       
        count++;
             
      }