What is a QMetaObject?
The QMetaObject is Qt’s implementation of the MetaObject pattern. It provides information about properties and methods of a QObject. The MetaObject pattern is sometimes known as the Reflection pattern. A class that has a MetaObject supports reflection. This is a feature found in many object-oriented languages.
How do you block a Qt signal?
If you just don’t want the signal to be emitted at one specific time, you can use QObject::blockSignals like this: bool oldState = checkBox->blockSignals(true); checkBox->setChecked(true); checkBox->blockSignals(oldState); The downside of this approach is that all signals will be blocked.
What is Qt_metacast?
The Qt Meta-Object System in Qt is responsible for the signals and slots inter-object communication mechanism, runtime type information, and the Qt property system. This object is available as QObject::metaObject().
What is Qt_metacall?
Qt’s meta-object system uses the qt_metacall() function to access the meta-information for a particular QObject object (its signals, slots, properties, etc.).
What is QObject?
QObject is the heart of the Qt Object Model. The central feature in this model is a very powerful mechanism for seamless object communication called signals and slots. You can connect a signal to a slot with connect() and destroy the connection with disconnect().
What is the use of Q_invokable?
To be able to call a method from QML, you must either mark it with Q_INVOKABLE or as a slot. I prefer Q_INVOKABLE if it’s not meant to be used as a slot, as its more minimal. The implementation of buttonClicked() can contain any C++ code. To make the main window instance accessible from QML, you must register it, e.g.
What is QQuickWidget?
The QQuickWidget class provides a widget for displaying a Qt Quick user interface. This class was introduced in Qt 5.3.
How can I block a cell phone signal?
Fortunately there is a solution: You can use a cell phone jammer to block their signals. Cell Phone Jammers . Buy a cell phone signal jamming device from eBay, Amazon or any online spy and gadget site. These devices will block signals anywhere from 10 to 200 feet, depending on the model that you decide to purchase.
Is it legal to block cell phone signals?
In the US, you can not legally block cell phone signals. Trying to block the signal is only addressing the symptom of the problem, not the root cause. This employer needs to determine why his employees are on their smart phones so much.
What is automatic block signal system?
Automatic block signaling (ABS) is a railroad communications system that consists of a series of signals that divide a railway line into a series of sections, or “blocks”. The system controls the movement of trains between the blocks using automatic signals.
How do you block a cell signal?
“There are some legal ways that you can block cell phone signals, but they are a little more difficult to do, and are definitely not portable. The first method would be to place a thick steel plate between the cell phone and the associated tower. This blocks the signal. It needs to be heavy and needs to be fairly large.