From d9b7d60df02178c640fb0a5c609cedad95c5c009 Mon Sep 17 00:00:00 2001 From: Sze Howe Koh Date: Sun, 29 Dec 2013 08:45:45 +0800 Subject: [PATCH] Doc: Polish Qt::ConnectionType descriptions MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit - 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 Reviewed-by: Topi Reiniö Reviewed-by: Giuseppe D'Angelo --- src/corelib/global/qnamespace.qdoc | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) diff --git a/src/corelib/global/qnamespace.qdoc b/src/corelib/global/qnamespace.qdoc index 90f38fd51c6..ae377e124b7 100644 --- a/src/corelib/global/qnamespace.qdoc +++ b/src/corelib/global/qnamespace.qdoc @@ -509,15 +509,14 @@ delivery at a later time. \value AutoConnection - (default) If the signal is emitted from a different thread than the - receiving object, the signal is queued, behaving as - Qt::QueuedConnection. Otherwise, the slot is invoked directly, - behaving as Qt::DirectConnection. The type of connection is + \b (Default) If the receiver \l{QObject#Thread Affinity}{lives in} the + thread that emits the signal, Qt::DirectConnection is used. Otherwise, + Qt::QueuedConnection is used. The connection type is determined when the signal is emitted. \value DirectConnection - The slot is invoked immediately, when the signal is - emitted. + The slot is invoked immediately when the signal is + emitted. The slot is executed in the signalling thread. \value QueuedConnection The slot is invoked when control returns to the event loop @@ -525,11 +524,10 @@ receiver's thread. \value BlockingQueuedConnection - Same as QueuedConnection, except the current thread blocks - until the slot returns. This connection type should only be - used where the emitter and receiver are in different - threads. \note Violating this rule can cause your - application to deadlock. + Same as Qt::QueuedConnection, except that the signalling thread blocks + until the slot returns. This connection must \e not be used if the + receiver lives in the signalling thread, or else the application + will deadlock. \value UniqueConnection This is a flag that can be combined with any one of the above