Arduino + Proccesing code error “disabling_serialevent()”

问题

I have some problems in my code, i can run it because i always get this error message

Error, disabling serialEvent() for COM3 null

import processing.serial.*;
Serial port;
String c = " ";
String d = " ";
String data = " ";
PFont font;
int index = 0;

void setup() {
    size(2024, 1024);
    port = new Serial(this, "COM3", 9600);

    port.bufferUntil('.');
    font = loadFont("run.vlw");
    textFont(font, 60);
}

void draw() {
    background(150, 50, 200);
    fill(46, 20, 2);
    text(c, 70, 175);
    fill(46, 20, 2);
    text(d, 70, 215);
}

void serialEvent(Serial port) {
    data = port.readStringUntil('.');
    data = data.substring(0, data.length() - 1);
    index = data.indexOf(",");
    c = data.substring(0, index);
    d = data.substring(index + 1, data.length());
}

I am new in this thing, sorry if i made a big mistake.

回答1:

Your serialEvent() code doesn't handle exceptions. It is likely that your handling of the serial data contains an error which subsequently causes an unhandled StringIndexOutOfBoundsException, so the program crashes. To be sure, we would need knowledge of the actual data that gets transmitted via COM3. So here are two suggestions:

1. Put the whole code inside of serialEvent() in a try/catch block and print out the exception's stack trace. This should give you more hints about what causes the crash.
2. Edit your question and add a snippet of your Arduino Serial Monitor's output.

Can't comment yet, so I have to post this as an answer.

来源：https://stackoverflow.com/questions/42618052/arduino-proccesing-code-error-disabling-serialevent