Using a button to continue your loop, or to break in switch case

Using Arduino Project Guidance
4

while(Serial.available()>0)
{
int incomingserial = Serial.read();
if(incomingserial == a)
{
while(sensorread==LOW)
{
Serial.print("This Is Case A");
digitalWrite(motor1, HIGH);
delay(500);
digitalWrite(motor1, LOW);
digitalWrite(transmitter, HIGH);
digitalWrite(buzzer1, HIGH);
sensorread=digitalRead(pinx);
}
}
}

The way I wrote it, the while statement will run indefinitely until sensorread becomes HIGH. Could you post your entire code?