(CC'ing the list just in case somebody else finds this useful) Olivier Roulet wrote:
I haven't tried with a directory of that size. Most of my directories are at most 50 images.That is in fact the design I started to use but then for other reasons I changed to a queuing mechanisme. And with your current version you do not get any troubles with more than 500<> picture ?
Sure. I was going to release it open source at some point when I was happy with it.May I ask if it is possible to see you code ? . I do not make any commercial application :-) It is just for personal use.
Here are some snippets from my code. I didn't send the whole thing because it's almost a thousand lines and most of it's entirely unrelated to the problem at hand.
ThumbnailView is a QIconView subclass which, given a directory, will display a list of thumbnails for all the image files in that directory. It caches the thumbnail images for faster loading the next time that same directory is used. ThumbnailView.setDirectory is what starts the whole process.
You'll notice that there's a lot of qApp.lock and unlock calls. Basically, any time the code has to interact with a Qt object that could possibly be in use by the Qt event loop on the main thread, it has to call QApplication.lock to stop the event processing thread from doing anything and then unlock once it's done. Without this, the app _will_ segfault. The lock/unlock sections also have to be fairly fine-grained otherwise the responsiveness of the app (which is what I was trying to gain with a background loading thread) is badly affected.
######################################################
class ThumbnailLoaderThread(QThread):
def __init__(self, view):
QThread.__init__(self)
self.view = view
def run(self):
self.view.loadThumbnails()
class ThumbnailView(QIconView):
def __init__(self, parent):
QIconView.__init__(self, parent)
self.unknownIcon = QPixmap(QImage(os.path.join(DATA_DIR, "unknown.png")))
# ... more init stuff ...
def setDirectory(self, directory):
if self.tlt: # thumbnail loader thread
self.cancelLoadingThumbnails()
qApp.unlock()
self.tlt.wait()
qApp.lock()
self.clear()
self.directory = directory
if not directory:
return
if not os.path.exists(directory):
return
files = os.listdir(directory)
for file in files:
path = os.path.join(directory, file)
if os.path.isfile(path) and file[-3:].upper() in SUPPORTED_FORMATS:
self.addThumbnail(path)
qApp.processEvents()
self.tlt = ThumbnailLoaderThread(self)
self.tlt.start()
self.tlt.wait(100) # this is very necessary, otherwise it segfaults
def addThumbnail(self, path):
item = QIconViewItem(self, os.path.basename(path), self.unknownIcon)
item.setKey(path)
def loadThumbnails(self):
self.cancelLoadingThumbnailsFlag = False
qApp.lock()
self.emit(PYSIGNAL("startedLoading"), (self.count(),))
qApp.unlock()
item = self.firstItem()
i = 0
while item:
path = str(item.key())
if os.path.isfile(path):
if self.cancelLoadingThumbnailsFlag:
break
# try to load a cached thumbnail image
thumbnail = self.loadThumbnail(path)
if not thumbnail:
if self.cancelLoadingThumbnailsFlag:
break
# make a new thumbnail image
thumbnail = self.makeThumbnail(path)
if self.cancelLoadingThumbnailsFlag:
break
if thumbnail:
# cache the thumbnail image to disk
self.saveThumbnail(thumbnail, path)
if self.cancelLoadingThumbnailsFlag:
break
if thumbnail:
# Set the current QListViewItem's pixmap
icon = QPixmap()
icon.convertFromImage(thumbnail)
qApp.lock()
item.setPixmap(icon)
qApp.unlock()
item = item.nextItem()
i += 1
qApp.lock()
self.emit(PYSIGNAL("loadedThumbnail"), (i, path))
qApp.unlock()
qApp.lock()
self.emit(PYSIGNAL("finishedLoading"), ())
if not self.cancelLoadingThumbnailsFlag:
# Select the first item
first = self.firstItem()
if first and self.currentItem() and not self.currentItem().isSelecte
d():
self.setSelected(first, True, False)
qApp.unlock()
######################################################
Ciao,
Gordon
_______________________________________________
PyKDE mailing list [EMAIL PROTECTED]
http://mats.gmd.de/mailman/listinfo/pykde
