Doc: Polish Qt::ConnectionType descriptions

- Shorten Qt::AutoConnection description, rearrange to match the order
  of the subsequent rows.
- Note the thread used in Qt::DirectConnection
- "Emitter's thread" is ambiguous -- a signal is not necessarily
  emitted from the thread that the emitter lives in.
- Misusing Qt::BlockingQueuedConnection WILL (not "can") cause a
  deadlock. Qt even issues an error message before it freezes.
- Remove the \note command -- it breaks the table and displays the note
  in a new paragraph.

Change-Id: Ib60cb665e0cd23e1e072402ec5d8be344b8454f7
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
Reviewed-by: Topi Reiniö <topi.reinio@digia.com>
Reviewed-by: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
This commit is contained in:
Sze Howe Koh 2013-12-29 08:45:45 +08:00 committed by The Qt Project
parent fe4ebf1269
commit d9b7d60df0

View File

@ -509,15 +509,14 @@
delivery at a later time. delivery at a later time.
\value AutoConnection \value AutoConnection
(default) If the signal is emitted from a different thread than the \b (Default) If the receiver \l{QObject#Thread Affinity}{lives in} the
receiving object, the signal is queued, behaving as thread that emits the signal, Qt::DirectConnection is used. Otherwise,
Qt::QueuedConnection. Otherwise, the slot is invoked directly, Qt::QueuedConnection is used. The connection type is
behaving as Qt::DirectConnection. The type of connection is
determined when the signal is emitted. determined when the signal is emitted.
\value DirectConnection \value DirectConnection
The slot is invoked immediately, when the signal is The slot is invoked immediately when the signal is
emitted. emitted. The slot is executed in the signalling thread.
\value QueuedConnection \value QueuedConnection
The slot is invoked when control returns to the event loop The slot is invoked when control returns to the event loop
@ -525,11 +524,10 @@
receiver's thread. receiver's thread.
\value BlockingQueuedConnection \value BlockingQueuedConnection
Same as QueuedConnection, except the current thread blocks Same as Qt::QueuedConnection, except that the signalling thread blocks
until the slot returns. This connection type should only be until the slot returns. This connection must \e not be used if the
used where the emitter and receiver are in different receiver lives in the signalling thread, or else the application
threads. \note Violating this rule can cause your will deadlock.
application to deadlock.
\value UniqueConnection \value UniqueConnection
This is a flag that can be combined with any one of the above This is a flag that can be combined with any one of the above