PyQt Tips and Tricks - Revision history

imported_>amigadave: /* Tips and Tricks */ move content from PyQt instant startup screen trick

2011-05-31T09:44:28Z

Tips and Tricks: move content from PyQt instant startup screen trick

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 </source>
 [http://talk.maemo.org/showpost.php?p=714507&postcount=1]
 == Example Applications ==

2010-11-12T13:41:45Z

add link

← Older revision		Revision as of 13:41, 12 November 2010
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	With ~~Meego~~ there is a lot of interest in developing applications in Qt rather than GTK. This page spawned from a [http://talk.maemo.org/showthread.php?t=56171 discussion thread].		With MeeGo there is a lot of interest in [[Qt4 development\|developing applications in Qt]] rather than GTK+. This page spawned from a [http://talk.maemo.org/showthread.php?t=56171 discussion thread].

	== Tips and Tricks ==		== Tips and Tricks ==

2010-09-11T17:18:43Z

Adding a performance note and a note for working with QThread

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 == Tips and Tricks ==
 === Identifying the Sender of a Signal ===
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 It is discouraged to inherit from <code>QThread</code> and to use <code>moveToThread</code> on the <code>QThread</code>.[http://labs.trolltech.com/blogs/2010/06/17/youre-doing-it-wrong].  A C++ example of how to use these is shown in a producer/consumer style application can be found on the [http://labs.trolltech.com/blogs/2006/12/04/threading-without-the-headache/ trolltech blog].
 ==== import threading ====

2010-07-18T10:10:23Z

Stacked Windows

← Older revision		Revision as of 10:10, 18 July 2010
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	<source lang="python">		<source lang="python">
	class ~~showWindowQtGui~~.QMainWindow):		class showWindow(QtGui.QMainWindow):
	def __init__(self, parent=None):		def __init__(self, parent=None):
	QtGui.QWidget.__init__(self, parent)		QtGui.QWidget.__init__(self, parent)

2010-06-18T08:19:42Z

wikify slightly

2010-06-17T18:30:43Z

QThread

← Older revision		Revision as of 18:30, 17 June 2010
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	=== QThread ===		=== QThread ===

			It is discouraged to inherit from QThread and to use moveToThread on the QThread.[http://labs.trolltech.com/blogs/2010/06/17/youre-doing-it-wrong]. A C++ example of how to use these is shown in a producer/consumer style application can be found on the [http://labs.trolltech.com/blogs/2006/12/04/threading-without-the-headache/ trolltech blog].

	=== import threading ===		=== import threading ===

2010-06-17T14:31:37Z

Example Applications

← Older revision		Revision as of 14:31, 17 June 2010
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	= Example Applications =		= Example Applications =
	This is an overview of some of the PyQt applications available for Maemo. For some of the apps, there's a brief outline of unique functions they might have that you might want for your app.		This is an overview of some of the PyQt applications available for Maemo. For some of the apps, there's a brief outline of unique functions they might have that you might want for your app.

			The official [http://www.riverbankcomputing.co.uk/software/pyqt/download PyQt] bindings come with python-based examples for many things. There's also examples for [http://maemo.org/packages/view/python2.5-qt4-doc/ PyQt on Maemo5] with python examples, as well.

	If you want to learn to become better in Python and Qt, reading code is one of the better ways to do it.		If you want to learn to become better in Python and Qt, reading code is one of the better ways to do it.

2010-06-17T14:25:54Z

Example Applications

← Older revision		Revision as of 14:25, 17 June 2010
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	= Example Applications =		= Example Applications =
			This is an overview of some of the PyQt applications available for Maemo. For some of the apps, there's a brief outline of unique functions they might have that you might want for your app.

	* ncalc		If you want to learn to become better in Python and Qt, reading code is one of the better ways to do it.
	* nclock
	* maesynth		* [http://maemo.org/packages/view/ncalc/ ncalc]
	** Uses QGraphicsView		* [http://maemo.org/packages/view/nclock/ nclock]
	* maelophone		* [http://maemo.org/packages/view/maesynth/ maesynth]
	* healthcheck		** Uses QGraphicsView to create a non-standard looking GUI
	* qlister		** Also plays sounds when keys are pressed
			* [http://maemo.org/packages/view/maelophone/ maelophone]
			* [http://maemo.org/packages/view/healthcheck/ healthcheck]
			** Gives examples of interacting with much of the hardware on the n900
			* [http://maemo.org/packages/view/qlister/ qlister]
	* Gonvert (1.0+)		* Gonvert (1.0+)
	* [http://maemo.org/packages/view/wifieye/ WifiEye]		* [http://maemo.org/packages/view/wifieye/ WifiEye]
	* [http://maemo.org/packages/view/maegirls/ MaeGirls]		* [http://maemo.org/packages/view/maegirls/ MaeGirls]
	* pyPianobar		* [http://maemo.org/packages/view/pypianobar/ pyPianobar]
	** Threading and Qt		** Threading and Qt
	* pyRadio		* [http://maemo.org/packages/view/pyradio/ pyRadio]
	** Threading and Qt		** Threading and Qt

2010-06-17T14:12:22Z

QTimer

← Older revision		Revision as of 14:12, 17 June 2010
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	=== QTimer ===		=== QTimer ===

	Spread the work across multiple callbacks to allow the UI to remain responsive. See multiple [http://www.rkblog.rk.edu.pl/w/p/qtimer-making-timers-pyqt4/ QTimer types]		Spread the work across multiple callbacks to allow the UI to remain responsive. See multiple [http://www.rkblog.rk.edu.pl/w/p/qtimer-making-timers-pyqt4/ QTimer types]. If you're not relying on third parties (anything that will block the interpreter - whether it be waiting on hardware or a call via XMLRPC) QTimers are probably a good choice.

			As an example, I wrote an app that would play a series of .jpg images as a movie in a player. While using a thread would work, using a QTimer worked great as well, since there was no waiting for hardware.

	== Stacked Windows ==		== Stacked Windows ==

2010-06-17T13:58:04Z

import threading

← Older revision		Revision as of 13:58, 17 June 2010
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	=== import threading ===		=== import threading ===

			It appears QThread initializes some TLS for data essential for thread safe signals and slots. Also when creating cross-thread signals it queues the signal emission rather than doing it immediately. These present problems when wanting to use the native Python Threading in a Qt application.[http://www.mail-archive.com/pyqt@riverbankcomputing.com/msg16062.html][http://www.mail-archive.com/pyqt@riverbankcomputing.com/msg16082.html]

			If the Python thread would not interact directly with Qt then using Python threads is fine without any consideration.

			Sometimes you must use Python threads with Qt like when porting applications. One solution to his is to pump messages into a queue and have an QTimer poll the queue periodically for tasks to process in the UI thread.[http://www.mail-archive.com/pyqt@riverbankcomputing.com/msg16062.html]

	=== QTimer ===		=== QTimer ===