Get hex from Qlineedit and send to serial port

[jefftee]

You don't need to specify the size of the byte array if you use QByteArray, that was my whole point. Here is your code using QByteArray and proper for loop bounds:

QString input = ui->data->text();
QStringList list1 = input.split(",");
int size = list1.size();
QByteArray senddata;
for (int i=0; i < size; i++){
    QString ran = list1 [i];
    bool ok;
    senddata[i]=ran.toInt(&ok,16);
}
 
serial->write(senddata.constData(), senddata.length());

QString input = ui->data->text();
QStringList list1 = input.split(",");
int size = list1.size();
QByteArray senddata;
for (int i=0; i < size; i++){
    QString ran = list1 [i];
    bool ok;
    senddata[i]=ran.toInt(&ok,16);
}

serial->write(senddata.constData(), senddata.length());

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[hovuquocan1997]

Thank you very much, that solved everything! Thanks for helping me so much, I really appreciate it!