<![CDATA[Led Indicator in Qt]]>Hi,
I want to design led indicator in qt4 i wrote some code cannot work for me
please find out the bug here the code is:
@
void MainWindow::on_pushButton_3_clicked()
{
sleep(2);
green();
sleep(2);
red();
}

void MainWindow::green()
{
ui->pushButton->setIcon(QIcon("/home/ubuntu/green.png"));
ui->pushButton->setIconSize(QSize(50,50));
ui->pushButton_2 ->setIcon(QIcon("/home/ubuntu/red_off.png"));
ui->pushButton_2 ->setIconSize(QSize(50,50));
}
void MainWindow::red()
{
ui->pushButton->setIcon(QIcon("/home/ubuntu/green_off.png"));
ui->pushButton->setIconSize(QSize(50,50));
ui->pushButton_2 ->setIcon(QIcon("/home/ubuntu/red_on.png"));
ui->pushButton_2 ->setIconSize(QSize(50,50));
}
@

[andreyc EDIT]: Added @ around the code

]]>https://forum.qt.io/topic/44615/led-indicator-in-qtRSS for NodeSun, 14 Jun 2026 15:50:15 GMTThu, 07 Aug 2014 17:48:49 GMT60<![CDATA[Reply to Led Indicator in Qt on Thu, 07 Aug 2014 18:19:15 GMT]]>The code in second post looks the same as in first.

What problem do you have with this code ?

I see only one issue so far.
The sleep() will stop event loop.
Use QTimer instead.

]]>https://forum.qt.io/post/238986https://forum.qt.io/post/238986Thu, 07 Aug 2014 18:19:15 GMT<![CDATA[Reply to Led Indicator in Qt on Thu, 07 Aug 2014 17:49:26 GMT]]>@
void MainWindow::on_pushButton_3_clicked()
{
sleep(2);
green();
sleep(2);
red();
}
void MainWindow::green()
{
ui->pushButton->setIcon(QIcon("/home/ubuntu/green.png"));
ui->pushButton->setIconSize(QSize(50,50));
ui->pushButton_2 ->setIcon(QIcon("/home/ubuntu/red_off.png"));
ui->pushButton_2 ->setIconSize(QSize(50,50));
}
void MainWindow::red()
{
ui->pushButton->setIcon(QIcon("/home/ubuntu/green_off.png"));
ui->pushButton->setIconSize(QSize(50,50));
ui->pushButton_2 ->setIcon(QIcon("/home/ubuntu/red_on.png"));
ui->pushButton_2 ->setIconSize(QSize(50,50));
}
@
[andreyc EDIT]: Added @ around the code

]]>https://forum.qt.io/post/238981https://forum.qt.io/post/238981Thu, 07 Aug 2014 17:49:26 GMT