QT Designer Issue

heedaf

This is really a strange issue that I'm having that I thought would be a simple thing but it is really giving me a headache. I've got an LCDNumber display widget that I'm trying to write to. I've found some sample code that updates the a clock every second.

void DigitalClock::showTime()
{
QTime time = QTime::currentTime();
QString text = time.toString("hh:mm:ss");
setDigitCount(8);
if ((time.second() % 2) == 0)
{
text[5] = ' ';
}
display(text);
// ui->lcdNumber->display(text);
}

I've included the //ui-->lcdNumber->display(text) as an example of what I'm trying to do. The following works just fine:

MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent), ui(new Ui::MainWindow)
{
ui->setupUi(this);
ui->lcdNumber->display(text);
}

Can anyone explain to me how I can get the DigitalClock section to update the lcdNumber box I created in QT creator?

Thanks!

killerman

You can create a signal in DigitalClock that will send the data and a slot in MainWindow that will receive it.

QObject::connect(yourDigitalClock, SIGNAL(yourSignal(QString)),
                 yourMainWindow, SLOT(setDisplay(QString)));

heedaf

Thanks for your reply! I've spent awhile on this and I could use more help. I've got the following

void DigitalClock::showTime()
{
QTime time = QTime::currentTime();
QString text = time.toString("hh:mm:ss");
if ((time.second() % 2) == 0)
text[2] = ' ';
display(text);
}

I need to pass the QString "text" to a lcdNumber box in the MainWindow and I've tried multiple configurations but I'm just not sure how it works. Could you please fix the what I've done wrong?

QObject::connect(showTime(), SIGNAL(time(Qstring)), MainWindow(), SLOT(ui->lcdNumber->Display(QString)));

It gives a "No instance of overloaded function "QObject::connect" matches the argument list". I tried the following

QObject connect(DigitalClock, SIGNAL(time(Qstring)), MainWindow(), SLOT(Display(QString)));

and it gives me a "expected a type specifier" for the SIGNAL and the SLOT

SGaist

Hi,

The SLOT macro only takes the slot name with argument type like shown in @killerman's example