connect(this->txtOutDir, SIGNAL(textEdited(QString)), this, SLOT(txtOutDirChanged()));
The autocomplete does not work when trying to complete in SIGNAL and SLOT declarations.
connect(this->txtOutDir, SIGNAL(textE...ctrl+space), this, SLOT(txtOu...ctrl+space)); //nothing happens.
I tested this in qt creator 4.6.2 and it works fine there.
[Edit André Hartmann: The reason for this behavior is, that Creator 4.7 and higher by default enables the Clang Code Model. Currently the only way to still get code completion for the macro-based SIGNAL and SLOT connection, Clang can be disabled in Help > About Plugins > Clang Code Model]