Fix build with Qt 5.6
Summary: QOverload<>::of() is new in Qt 5.7, so "emulate" it with static_cast<>() when building against lower Qt versions.
Test Plan:
Kexi 3.1.0 builds fine now on openSUSE Leap 42.3 with Qt 5.6.2.
Before I got these compiler errors:
/home/abuild/rpmbuild/BUILD/kexi-3.1.0/src/widget/KexiFileRequester.cpp: In member function 'void KexiFileRequester::init()':
/home/abuild/rpmbuild/BUILD/kexi-3.1.0/src/widget/KexiFileRequester.cpp:479:30: error: 'QOverload' was not declared in this scope
connect(d->locationEdit, QOverload<>::of(&KUrlComboBox::returnPressed),
^
/home/abuild/rpmbuild/BUILD/kexi-3.1.0/src/widget/KexiFileRequester.cpp:479:40: error: expected primary-expression before '>' token
connect(d->locationEdit, QOverload<>::of(&KUrlComboBox::returnPressed),
^
/home/abuild/rpmbuild/BUILD/kexi-3.1.0/src/widget/KexiFileRequester.cpp:479:41: error: '::of' has not been declared
connect(d->locationEdit, QOverload<>::of(&KUrlComboBox::returnPressed),
^Still builds fine with Qt 5.9.4 and 5.10.0 too...
Reviewers: staniek, piggz
Reviewed By: staniek
Subscribers: KEXI
Tags: KEXI
Differential Revision: https://phabricator.kde.org/D11544