<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"> <head> <title>KAutoSaveFile</title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <meta http-equiv="Content-Style-Type" content="text/css" /> <link rel="stylesheet" type="text/css" href="../common/doxygen.css" /> <link rel="stylesheet" media="screen" type="text/css" title="KDE Colors" href="../common/kde.css" /> </head> <body> <div id="container"> <div id="header"> <div id="header_top"> <div> <div> <img alt ="" src="../common/top-kde.jpg"/> KDE 4.4 PyKDE API Reference </div> </div> </div> <div id="header_bottom"> <div id="location"> <ul> <li>KDE's Python API</li> </ul> </div> <div id="menu"> <ul> <li><a href="../modules.html">Overview</a></li> <li><a href="http://techbase.kde.org/Development/Languages/Python">PyKDE Home</a></li> <li><a href="http://kde.org/family/">Sitemap</a></li> <li><a href="http://kde.org/contact/">Contact Us</a></li> </ul> </div> </div> </div> <div id="body_wrapper"> <div id="body"> <div id="right"> <div class="content"> <div id="main"> <div class="clearer"> </div> <h1>KAutoSaveFile Class Reference</h1> <code>from PyKDE4.kdecore import *</code> <p> Inherits: <a href="http://www.riverbankcomputing.co.uk/static/Docs/PyQt4/html/qfile.html">QFile</a> → <a href="http://www.riverbankcomputing.co.uk/static/Docs/PyQt4/html/qiodevice.html">QIODevice</a> → <a href="http://www.riverbankcomputing.co.uk/static/Docs/PyQt4/html/qobject.html">QObject</a><br /> <h2>Detailed Description</h2> <p>\class KAutoSaveFile kautosavefile.h <KAutoSaveFile> </p> <p> Creates and manages a temporary "auto-save" file. Autosave files are temporary files that applications use to store the unsaved data in a file they have open for editing. KAutoSaveFile allows you to easily create and manage such files, as well as to recover the unsaved data left over by a crashed or otherwise gone process. </p> <p> Each KAutoSaveFile object is associated with one specific file that the application holds open. KAutoSaveFile is also a QObject, so it can be reparented to the actual opened file object, so as to manage the lifetime of the temporary file. </p> <p> Typical use consists of: - verifying whether stale autosave files exist for the opened file - deciding whether to recover the old, autosaved data - if not recovering, creating a KAutoSaveFile object for the opened file - during normal execution of the program, periodically save unsaved data into the KAutoSaveFile file. </p> <p> KAutoSaveFile holds a lock on the autosave file, so it's safe to delete the file and recreate it later. Because of that, disposing of stale autosave files should be done with releaseLock(). No lock is held on the managed file. </p> <p> Examples: Opening a new file: <pre class="fragment"> void Document.open(const KUrl &url) { // check whether autosave files exist: QList<KAutoSaveFile *> staleFiles = KAutoSaveFile.staleFiles(url); if (!staleFiles.isEmpty()) { if (KMessageBox.questionYesNo(parent, "Auto-saved files exist. Do you want to recover them now?", "File Recovery", "Recover", "Don't recover") == KMessage.Yes) { recoverFiles(staleFiles); return; } else { // remove the stale files foreach (KAutoSaveFile *stale, staleFiles) { stale->open(QIODevice.ReadWrite); delete stale; } } } // create new autosave object m_autosave = new KAutoSaveFile(url, this); // continue the process of opening file 'url' ... } </pre> </p> <p> The function recoverFiles could loop over the list of files and do this: <pre class="fragment"> foreach (KAutoSaveFile *stale, staleFiles) { if (!stale->open(QIODevice.ReadWrite)) { // show an error message; we could not steal the lockfile // maybe another application got to the file before us? delete stale; continue; } Document *doc = new Document; doc->m_autosave = stale; stale->setParent(doc); // reparent doc->setUrl(stale->managedFile()); doc->setContents(stale->readAll()); doc->setState(Document.Modified); // mark it as modified and unsaved documentManager->addDocument(doc); } </pre> </p> <p> If the file is unsaved, periodically write the contents to the save file: <pre class="fragment"> if (!m_autosave->isOpen() && !m_autosave->open(QIODevice.ReadWrite)) { // show error: could not open the autosave file } m_autosave->write(contents()); </pre> </p> <p> When the user saves the file, the autosaved file is no longer necessary and can be removed or emptied. <pre class="fragment"> m_autosave->resize(0); // leaves the file open </pre> </p> <p> <pre class="fragment"> m_autosave->remove(); // closes the file </pre> </p> <p> <dl class="author" compact><dt><b>Author:</b></dt><dd> Jacob R Rideout <kde@jacobrideout.net> </dd></dl> </p> <table border="0" cellpadding="0" cellspacing="0"><tr><td colspan="2"><br><h2>Methods</h2></td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="#KAutoSaveFile">__init__</a> (self, <a href="../kdecore/KUrl.html">KUrl</a> filename, <a href="http://www.riverbankcomputing.co.uk/static/Docs/PyQt4/html/qobject.html">QObject</a> parent=0)</td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="#KAutoSaveFile">__init__</a> (self, <a href="http://www.riverbankcomputing.co.uk/static/Docs/PyQt4/html/qobject.html">QObject</a> parent=0)</td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="#KAutoSaveFile">__init__</a> (self, <a href="../kdecore/KAutoSaveFile.html">KAutoSaveFile</a> a0)</td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top">[<a href="../kdecore/KAutoSaveFile.html">KAutoSaveFile</a>] </td><td class="memItemRight" valign="bottom"><a class="el" href="#allStaleFiles">allStaleFiles</a> (self, <a href="http://www.riverbankcomputing.co.uk/static/Docs/PyQt4/html/qstring.html">QString</a> applicationName=QString())</td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top"><a href="../kdecore/KUrl.html">KUrl</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="#managedFile">managedFile</a> (self)</td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top">bool </td><td class="memItemRight" valign="bottom"><a class="el" href="#open">open</a> (self, <a href="http://www.riverbankcomputing.co.uk/static/Docs/PyQt4/html/qiodevice::openmode.html">QIODevice.OpenMode</a> openmode)</td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="#releaseLock">releaseLock</a> (self)</td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="#setManagedFile">setManagedFile</a> (self, <a href="../kdecore/KUrl.html">KUrl</a> filename)</td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top">[<a href="../kdecore/KAutoSaveFile.html">KAutoSaveFile</a>] </td><td class="memItemRight" valign="bottom"><a class="el" href="#staleFiles">staleFiles</a> (self, <a href="../kdecore/KUrl.html">KUrl</a> filename, <a href="http://www.riverbankcomputing.co.uk/static/Docs/PyQt4/html/qstring.html">QString</a> applicationName=QString())</td></tr> </table> <hr><h2>Method Documentation</h2><a class="anchor" name="KAutoSaveFile"></a> <div class="memitem"> <div class="memproto"> <table class="memname"><tr> <td class="memname">__init__</td> <td>(</td> <td class="paramtype"> <em>self</em>, </td> <td class="paramname"></td> </tr><tr> <td class="memname"></td> <td></td> <td class="paramtype"><a href="../kdecore/KUrl.html">KUrl</a> </td> <td class="paramname"><em>filename</em>, </td> </tr> <tr> <td class="memname"></td> <td></td> <td class="paramtype"><a href="http://www.riverbankcomputing.co.uk/static/Docs/PyQt4/html/qobject.html">QObject</a> </td> <td class="paramname"><em>parent=0</em></td> </tr> <tr> <td></td> <td>)</td> <td></td> <td></td> <td width="100%"> </td> </tr></table> </div> <div class="memdoc"><p>Constructs a KAutoSaveFile for file <b>filename.</b> The temporary file is not opened or created until actually needed. The file <b>filename</b> does not have to exist for KAutoSaveFile to be constructed (if it exists, it will not be touched). </p> <p> </p><dl compact><dt><b>Parameters:</b></dt><dd> <table border="0" cellspacing="2" cellpadding="0"> <tr><td></td><td valign="top"><em>filename</em> </td><td> the filename that this KAutoSaveFile refers to <tr><td></td><td valign="top"><em>parent</em> </td><td> the parent object </td></tr> </table></dl> <p> </p></div></div><a class="anchor" name="KAutoSaveFile"></a> <div class="memitem"> <div class="memproto"> <table class="memname"><tr> <td class="memname">__init__</td> <td>(</td> <td class="paramtype"> <em>self</em>, </td> <td class="paramname"></td> </tr><tr> <td class="memname"></td> <td></td> <td class="paramtype"><a href="http://www.riverbankcomputing.co.uk/static/Docs/PyQt4/html/qobject.html">QObject</a> </td> <td class="paramname"><em>parent=0</em></td> </tr> <tr> <td></td> <td>)</td> <td></td> <td></td> <td width="100%"> </td> </tr></table> </div> <div class="memdoc"><p> Constructs a KAutoSaveFile object. Note that you need to call setManagedFile() before calling open(). </p> <p> </p><dl compact><dt><b>Parameters:</b></dt><dd> <table border="0" cellspacing="2" cellpadding="0"> <tr><td></td><td valign="top"><em>parent</em> </td><td> the parent object </td></tr> </table></dl> <p> </p></div></div><a class="anchor" name="KAutoSaveFile"></a> <div class="memitem"> <div class="memproto"> <table class="memname"><tr> <td class="memname">__init__</td> <td>(</td> <td class="paramtype"> <em>self</em>, </td> <td class="paramname"></td> </tr><tr> <td class="memname"></td> <td></td> <td class="paramtype"><a href="../kdecore/KAutoSaveFile.html">KAutoSaveFile</a> </td> <td class="paramname"><em>a0</em></td> </tr> <tr> <td></td> <td>)</td> <td></td> <td></td> <td width="100%"> </td> </tr></table> </div> <div class="memdoc"></div></div><a class="anchor" name="allStaleFiles"></a> <div class="memitem"> <div class="memproto"> <table class="memname"><tr> <td class="memname">[<a href="../kdecore/KAutoSaveFile.html">KAutoSaveFile</a>] allStaleFiles</td> <td>(</td> <td class="paramtype"> <em>self</em>, </td> <td class="paramname"></td> </tr><tr> <td class="memname"></td> <td></td> <td class="paramtype"><a href="http://www.riverbankcomputing.co.uk/static/Docs/PyQt4/html/qstring.html">QString</a> </td> <td class="paramname"><em>applicationName=QString()</em></td> </tr> <tr> <td></td> <td>)</td> <td></td> <td></td> <td width="100%"> </td> </tr></table> </div> <div class="memdoc"><p>Returns all stale autosave files left behind by crashed or otherwise gone instances of this application. </p> <p> If not given, the application name is obtained from QCoreApplication, so be sure to have set it correctly before calling this function. </p> <p> See staleFiles() for information on the returned objects. </p></div></div><a class="anchor" name="managedFile"></a> <div class="memitem"> <div class="memproto"> <table class="memname"><tr> <td class="memname"><a href="../kdecore/KUrl.html">KUrl</a> managedFile</td> <td>(</td> <td class="paramtype"> </td> <td class="paramname"><em>self</em> )</td> <td width="100%"> </td> </tr> </table> </div> <div class="memdoc"><p>Retrieves the URL of the file managed by KAutoSaveFile. This is the same URL that was given to setManagedFile() or the KAutoSaveFile constructor. </p> <p> This is the name of the real file being edited by the application. To get the name of the temporary file where data can be saved, use fileName() (after you have called open()). </p></div></div><a class="anchor" name="open"></a> <div class="memitem"> <div class="memproto"> <table class="memname"><tr> <td class="memname">bool open</td> <td>(</td> <td class="paramtype"> <em>self</em>, </td> <td class="paramname"></td> </tr><tr> <td class="memname"></td> <td></td> <td class="paramtype"><a href="http://www.riverbankcomputing.co.uk/static/Docs/PyQt4/html/qiodevice::openmode.html">QIODevice.OpenMode</a> </td> <td class="paramname"><em>openmode</em></td> </tr> <tr> <td></td> <td>)</td> <td></td> <td></td> <td width="100%"> </td> </tr></table> </div> <div class="memdoc"><p>Opens the autosave file and locks it if it wasn't already locked. The name of the temporary file where data can be saved to will be set by this function and can be retrieved with fileName(). It will not change unless releaseLock() is called. No other application will attempt to edit such a file either while the lock is held. </p> <p> </p><dl compact><dt><b>Parameters:</b></dt><dd> <table border="0" cellspacing="2" cellpadding="0"> <tr><td></td><td valign="top"><em>openmode</em> </td><td> the mode that should be used to open the file, probably QIODevice.ReadWrite </td></tr> </table></dl> <p> <dl class="return" compact><dt><b>Returns:</b></dt><dd> true if the file could be opened (= locked and created), false if the operation failed </dd></dl> </p></div></div><a class="anchor" name="releaseLock"></a> <div class="memitem"> <div class="memproto"> <table class="memname"><tr> <td class="memname"> releaseLock</td> <td>(</td> <td class="paramtype"> </td> <td class="paramname"><em>self</em> )</td> <td width="100%"> </td> </tr> </table> </div> <div class="memdoc"><p>Closes the autosave file resource and removes the lock file. The file name returned by fileName() will no longer be protected and can be overwritten by another application at any time. To obtain a new lock, call open() again. </p> <p> This function calls remove(), so the autosave temporary file will be removed too. </p></div></div><a class="anchor" name="setManagedFile"></a> <div class="memitem"> <div class="memproto"> <table class="memname"><tr> <td class="memname"> setManagedFile</td> <td>(</td> <td class="paramtype"> <em>self</em>, </td> <td class="paramname"></td> </tr><tr> <td class="memname"></td> <td></td> <td class="paramtype"><a href="../kdecore/KUrl.html">KUrl</a> </td> <td class="paramname"><em>filename</em></td> </tr> <tr> <td></td> <td>)</td> <td></td> <td></td> <td width="100%"> </td> </tr></table> </div> <div class="memdoc"><p>Sets the URL of the file managed by KAutoSaveFile. This should be the name of the real file being edited by the application. If the file was previously set, this function calls releaseLock(). </p> <p> </p><dl compact><dt><b>Parameters:</b></dt><dd> <table border="0" cellspacing="2" cellpadding="0"> <tr><td></td><td valign="top"><em>filename</em> </td><td> the filename that this KAutoSaveFile refers to </td></tr> </table></dl> <p> </p></div></div><a class="anchor" name="staleFiles"></a> <div class="memitem"> <div class="memproto"> <table class="memname"><tr> <td class="memname">[<a href="../kdecore/KAutoSaveFile.html">KAutoSaveFile</a>] staleFiles</td> <td>(</td> <td class="paramtype"> <em>self</em>, </td> <td class="paramname"></td> </tr><tr> <td class="memname"></td> <td></td> <td class="paramtype"><a href="../kdecore/KUrl.html">KUrl</a> </td> <td class="paramname"><em>filename</em>, </td> </tr> <tr> <td class="memname"></td> <td></td> <td class="paramtype"><a href="http://www.riverbankcomputing.co.uk/static/Docs/PyQt4/html/qstring.html">QString</a> </td> <td class="paramname"><em>applicationName=QString()</em></td> </tr> <tr> <td></td> <td>)</td> <td></td> <td></td> <td width="100%"> </td> </tr></table> </div> <div class="memdoc"><p>Checks for stale autosave files for <b>filename.</b> Returns a list of autosave files that contain autosaved data left behind by other instances of the application, due to crashing or otherwise uncleanly exiting. </p> <p> It is the application's job to determine what to do with such unsaved data. Generally, this is done by asking the user if he wants to see the recovered data, and then allowing the user to save if he wants to. </p> <p> If not given, the application name is obtained from QCoreApplication, so be sure to have set it correctly before calling this function. </p> <p> This function returns a list of unopened KAutoSaveFile objects. By calling open() on them, the application will steal the lock. Subsequent releaseLock() or deleting of the object will then erase the stale autosave file. </p></div></div> </div> </div> </div> <div id="left"> <div class="menu_box"> <div class="nav_list"> <ul> <li><a href="../allclasses.html">Full Index</a></li> </ul> </div> <a name="cp-menu" /><div class="menutitle"><div> <h2 id="cp-menu-project">Modules</h2> </div></div> <div class="nav_list"> <ul><li><a href="../akonadi/index.html">akonadi</a></li> <li><a href="../dnssd/index.html">dnssd</a></li> <li><a href="../kdecore/index.html">kdecore</a></li> <li><a href="../kdeui/index.html">kdeui</a></li> <li><a href="../khtml/index.html">khtml</a></li> <li><a href="../kio/index.html">kio</a></li> <li><a href="../knewstuff/index.html">knewstuff</a></li> <li><a href="../kparts/index.html">kparts</a></li> <li><a href="../kutils/index.html">kutils</a></li> <li><a href="../nepomuk/index.html">nepomuk</a></li> <li><a href="../phonon/index.html">phonon</a></li> <li><a href="../plasma/index.html">plasma</a></li> <li><a href="../polkitqt/index.html">polkitqt</a></li> <li><a href="../solid/index.html">solid</a></li> <li><a href="../soprano/index.html">soprano</a></li> </ul></div></div> </div> </div> <div class="clearer"/> </div> <div id="end_body"></div> </div> <div id="footer"><div id="footer_text"> This documentation is maintained by <a href="mailto:simon@simonzone.com">Simon Edwards</a>.<br /> KDE<sup>®</sup> and <a href="../images/kde_gear_black.png">the K Desktop Environment<sup>®</sup> logo</a> are registered trademarks of <a href="http://ev.kde.org/" title="Homepage of the KDE non-profit Organization">KDE e.V.</a> | <a href="http://www.kde.org/contact/impressum.php">Legal</a> </div></div> </body> </html>