> -------------------------------------------------------------------
> QFont: It is not safe to use text and fonts outside the gui thread
> -------------------------------------------------------------------
>
> See my earlier mail,
> http://developer.classpath.org/pipermail/classpath/2006-February/000069.htm
>l
Hmm, it might be the case that this is really some weird interoperability
between pthread's usage of Qt, the VM and Classpath.
First a look at the function that creates this warning, in
// from src/gui/text/qfont.cpp:
void qt_font_tread_test()
{
if (QApplication::instance() && QThread::currentThread()
!= QApplication::instance()->thread())
qWarning("QFont: It is not safe to use text and fonts outside \
the gui thread");
}
This function get's called in two of the four QFont constructors.
QApplication::instance() returns the QApplication object or NULL.
QThread::currentThread() is defined as a static method like this:
// from src/corelib/thread/qthread_unix.cpp:
QThread *QThread::currentThread()
{
pthread_once(¤t_thread_key_once, create_current_thread_key);
return reinterpret_cast<QThread *>
(pthread_getspecific(current_thread_key));
}
This means that some thread id is stored in the per-thread specific area of
each thread and that Qt just safely casts this to a QThread pointer.
QApplication::instance()->thread() just points is to the thread() method of
the QObject:
// src/corelib/kernel/qobject.cpp
QThread *QObject::thread() const
{ return QThreadPrivate::threadForId(d_func()->thread); }
But here my knowledge is at the end. I've no knowledge about the internals of
Qt's d_func or QThreadPrivate.
When I augment the qt_font_tread_test() from above and let a mini AWT app run,
then I see:
Java_gnu_java_awt_peer_qt_QtFontPeer_create: (nil) QThread::currentThread()
Java_gnu_java_awt_peer_qt_QtFontPeer_create: 0x8093618
QApplication::instance()->thread()
QFont: It is not safe to use text and fonts outside the gui thread
Java_gnu_java_awt_peer_qt_QtFontPeer_create: (nil) QThread::currentThread()
Java_gnu_java_awt_peer_qt_QtFontPeer_create: 0x8093618
QApplication::instance()->thread()
QFont: It is not safe to use text and fonts outside the gui thread
Java_gnu_java_awt_peer_qt_QtFontPeer_create: (nil) QThread::currentThread()
Java_gnu_java_awt_peer_qt_QtFontPeer_create: 0x8093618
QApplication::instance()->thread()
QFont: It is not safe to use text and fonts outside the gui thread
Java_gnu_java_awt_peer_qt_QtFontPeer_create: (nil) QThread::currentThread()
Java_gnu_java_awt_peer_qt_QtFontPeer_create: 0x8093618
QApplication::instance()->thread()
QFont: It is not safe to use text and fonts outside the gui thread
QWidget::setMinimumSize: The smallest allowed size is (0,0)
Java_gnu_java_awt_peer_qt_QtFontPeer_create: (nil) QThread::currentThread()
Java_gnu_java_awt_peer_qt_QtFontPeer_create: 0x8093618
QApplication::instance()->thread()
QFont: It is not safe to use text and fonts outside the gui thread
QWidget::setMinimumSize: The smallest allowed size is (0,0)
Java_gnu_java_awt_peer_qt_QtFontPeer_create: (nil) QThread::currentThread()
Java_gnu_java_awt_peer_qt_QtFontPeer_create: 0x8093618
QApplication::instance()->thread()
QFont: It is not safe to use text and fonts outside the gui thread
Java_gnu_java_awt_peer_qt_QtFontPeer_create: (nil) QThread::currentThread()
Java_gnu_java_awt_peer_qt_QtFontPeer_create: 0x8093618
QApplication::instance()->thread()
QFont: It is not safe to use text and fonts outside the gui thread
Java_gnu_java_awt_peer_qt_QtFontPeer_create: 0x8093618
QThread::currentThread()
Java_gnu_java_awt_peer_qt_QtFontPeer_create: 0x8093618
QApplication::instance()->thread()
Java_gnu_java_awt_peer_qt_QtFontPeer_create: 0x8093618
QThread::currentThread()
Java_gnu_java_awt_peer_qt_QtFontPeer_create: 0x8093618
QApplication::instance()->thread()
Java_gnu_java_awt_peer_qt_QtFontPeer_create: 0x8093618
QThread::currentThread()
Java_gnu_java_awt_peer_qt_QtFontPeer_create: 0x8093618
QApplication::instance()->thread()
Java_gnu_java_awt_peer_qt_QtFontPeer_create: 0x8093618
QThread::currentThread()
Java_gnu_java_awt_peer_qt_QtFontPeer_create: 0x8093618
QApplication::instance()->thread()
Now, what to make out of this info?
