Wt

The WApplication::exposedSignals_ map uses std::string keys that contain the sender-object's id(). In consequence, if an object changes its id during its lifecycle, it will fail to unregister those of its signals in its destructor, which were registered before the id change. This can leave exposedSignals_ with dangling references, and crashes on me somewhere down the road.

There is a subtle bug in WWebWidget's id() bookkeeping, which falls into exactly this trap in the context of

WAbstractItemView::setDragEnabled(true)
dragWidget_->setId(id() + "dw");
WApplication::addExposedSignal( ... scrollVisibilityChanged ...)

The attached patch fixes that.