installSignalHandler
installSignalHandler(objectOrName, signalSignature, handlerFunctionName)
This function installs a Qt (not Unix!) signal handler that eavesdrops on the specified objectOrName widget. The signalSignature must be the exact signature used in C++ with no parameter names—for example, "activated(int)" or "triggered(QAction*)". The handlerFunctionName (which must be passed as a string, not as a function reference), will be called whenever the specified widget emits the specified signal and will be passed a reference to the object that emitted the signal, followed by all the signal's arguments (if there are any).
Note: When defining signal handlers of QML signals, the argument types still must be the C++ types. In particular, this means that for a real QML argument, you must use the C++ double type, and for a string QML type, you must use QString.
As is usual with Squish functions, the objectOrName widget must exist at the time this function is called. This requirement is relaxed by the installLazySignalHandler(name, signalSignature, handlerFunctionName) function which can only accept a symbolic or real name, but of an object that need not exist when the function is called. Nonetheless, it is best to use this installSignalHandler function whenever possible since it is potentially a lot faster than the installLazySignalHandler(name, signalSignature, handlerFunctionName) function.
Where possible the signal's arguments are passed as types that can be handled normally such as numbers, strings, or their actual Qt types such as QAction or QTableWidgetItem. However, some types are sent as plain Squish Objects; custom types and other unrecognized types are passed as strings.
For an example, see How to Use Qt Signal Handlers.
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