Porting Applications to KDE 2.0

Last Modified on November 28, 2000

This document contains the changes you have to apply to programs written for KDE1.1 when you want to port them to KDE2.0.

As a start you should have a look at doc/porting.doc in the Qt package, or this page online.

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Getting started

The first step to get your KDE application to compile under KDE 2.0, is to detect KDE 2.0 and Qt 2.x at configure time. The easiest way to get a working autoconf/automake framework, is to either use KDevelop or kapptemplate (available in CVS under the module "tdesdk"), to generate a new application template. Replace the generated source files by yours and adapt Makefile.am accordingly.

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Global changes

We did our best to clean up the header files of tdelibs, so they do not include unnecessary bloat for your application. As a consequence, you may notice that some header files are missing from your source files as they have been included before by kapp.h for example. There is a script in tdesdk/scripts called "fixheaders" that takes care of most of these cases. Just call "make -k 2>&1 | perl .../fixheaders" and it will try to look after the error messages and add includes as it recognize the errors.

Also, if your code does not compile and complains about missing member functions, you should check for methods that started with get...(). These methods have been renamed to xy*() for consistency.

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automoc/am_edit, Makefile.am tags

On the subject of the compilation framework, automoc has been removed from the admin directory. It has been replaced by am_edit which provides a lot of additional features.

METASOURCES=AUTO still does the job of generating the appropriate moc files, but in addition, you should use KDE_ICON for the icons representing the application (and naming those icons conforming to lo16-app-<appname>.png), and install the application-specific icons under $(kde_datadir)/<appname>/pics.

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doesn't hold any longer a TDELocale instance. With this getLocale() and isLocaleInstantiated are now replaced by TDEGlobal::locale()

it also doesn't hold a KiconLoader instance. As this also getIconLoader() has been removed. Replace kapp->getIconLoader()->loadIcon() with BarIcon() or use TDEGlobal::iconLoader() instead of getIconLoader()

kde_*dir() have been removed as they require a unique top level directory for all applications (TDEDIR). This concept doesn't exist in KDE 2.0 any more, it has been replaced with "multiple levels of directories", set in TDEDIRS, so that it's possible to have global settings and group settings, applied before user settings.

Replace code that uses kde_*dir() + filename with calls to locate(filetype, filename) where filetype is what * used to be in kde_*dir(). locate is defined as function in kstddirs.h to call TDEGlobal::dirs()->findResource.

Use locateLocal to get the path of a writable file. For instance, TDEApplication::localconfigdir()+filename is now locateLocal( "config", filename ), but for most cases, simply using TDEGlobal::config() is enough, if you're happy with saving the application's configuration into appnamerc, or KSimpleConfig cfg("anothercfgfile") to create a config file with another name.

generalFont() and fixedFont() are deprecated and will be removed soon. Please use TDEGlobalSettings::generalFont() and TDEGlobalSettings::fixedFont() instead.

appName() is deprecated. Please use TQApplication::name() or instanceName instead.

The methods tempSaveName() and checkRecoverFile() return QString now. The returned values must _not_ be free()d.

helpMenu() has been moved to TDEMainWindow. aboutKDE(), aboutApp() and appHelpActivated() have all been removed See section for TDEMainWindow for more info.

The TDEApplication constructor has changed. Command line arguments and program name should no longer be passed to TDEApplication but to TDECmdLineArgs. TDECmdLineArgs performs command line parsing and a command line help. See below for more info.

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TDECmdLineArgs is a new class that handles command line parsing and command line help. It is now required that your application specifies at least:

TDECmdLineArgs itself will add the command line options supported by Qt and TDEApplication.

You can also use the TDEAboutData class to specify name, description and version.

In return for this information you can query TDECmdLineArgs whether an certain option was specified on the command line and your application now automatically supports --help and --version. It aborts with a useful error message when the command line contains a syntax error. See tdelibs/tdecore/tdecmdlineargs.h for more info.

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i18n is no longer a macro


but a function on its own. klocale is obsolete and replace every call to klocale->translate with i18n.

The return value of i18n is also no longer a const char*, but a unicode TQString.

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TDEGlobal: access to KDE global objects.

TDEGlobal allows centralized access to KDE global objects without including extraneous headers. object creation is deferred if possible.

All methods are static and headers for returned types are not included. You must have created a TDEApplication object before the methods can be used.

      #include <tdeglobal.h>
      #include <tdeconfig.h>      // Needed to use TDEConfig
      #include <tdelocale.h>      // Needed to use TDELocale
      #include <kiconloader.h>  // Needed to use TDEIconLoader
        	TDEConfig *appcfg = TDEGlobal::config();
	        TQString mystr	 = i18n( "This is a string" );

		TDEIconLoader *loader = TDEGlobal::iconLoader();

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TDEIconLoader in 1.1 used to mix icons for applications and for toolbars. This has changed, so you may notice that your application doesn't find the right icons. loadIcon (used by BarIcon) returns only toolbar icons.

If you need icons for applications, use loadApplicationIcon.

loadMiniIcon and loadApplicationMiniIcon have been removed, instead loadApplicationIcon now takes a "size" argument where you can specify the size of the icon (small, medium, large).

The other big change you may notice, is that ICON and Icon have been removed as they caused big confusion for not loading application icons (see above). For this we added BarIcon which does the same as ICON before. The third change in this row is that loadIcon doesn't need the extension anymore, but looks for standard extensions (png, xpm) itself. If you hard- coded .xpm, loadIcon will issue a warning at runtime, but will still work in stripping off the .xpm part

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KTMainWindow has been replaced with TDEMainWindow.

The TDEMainWindow constructor needs a parent widget as first argument. You can use 0 for this.

setView() has been replaced with setCentralWidget().

view() has been replaced with centralWidget().

addToolBar() has been removed, it is not needed any more.

setMenu(...) has been removed, it is not needed any more.

setStatusBar(...) has been removed, it is not needed any more.

updateRects() has been removed, it is not needed any more.

enableStatusBar(...) has been removed, use statusBar()->show() and/or statusBar()->hide() instead.

enableToolBar(...) has been removed, use toolBar()->show() and/or toolBar()->hide() instead.

view_* public variables do no longer exist. There is really no reason for an app to use this information. If you do need it anyway, use mainViewGeometry() instead.

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helpMenu() has been moved to TDEMainWindow from TDEApplication (kapp).

Both the "About KDE" and the "About <Application>" dialog boxes are now modeless. "About KDE" is a completely new widget.

If you used in the toplevel window (that is derived from TDEMainWindow) "kapp->helpMenu( bool, TQString )" to get the help menu you must now change this to "helpMenu( TQString )". The TQString defaults to TQString::null so it is sufficient to write helpMenu().

The old aboutKDE(), aboutApp() and appHelpActivated() of TDEApplication have all been removed. If you need direct access to these or need access to a help menu in a class that is not derived from TDEMainWindow then allocate an instance of the new class KHelpMenu. See KDE 2.0 API reference or khelpmenu.h (tdeui) for additional info.

Espen Sand <espen@kde.org>

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enable(...) is depreciated, use show()/hide() instead.

enableFloating(...) has been removed, use enableMoving() instead.

setMaxHeight() is depreciated, use setMaximumHeight() instead.

maxHeight() is depreciated, use maximumHeight() instead.

setMaxWidth() is depreciated, use setMaximumWidth() instead.

maxWidth() is depreciated, use maximumWidth() instead.

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Starting other programs

In KDE 2.0 there are several ways to start other programs from within your application. Here is a short summary of your options with reasons why you should or should not use them.

1. fork + exec

You never want to use this unless you have a very good reason why it is impossible to use TDEProcess.

2. TDEProcess

You want to use this if you need to start a new process which needs to be a child of your process, e.g. because you want to catch stdout/stderr or need to send it data via stdin. You should never use this to start other KDE applications unless your application is called kgdb :-) If you need to send/receive text like data to/from the process, you are probably better off with KProcIO

3. KProcIO

Like TDEProcess. Unlike TDEProcess, this class actually makes it easy to send data to and receive data from the process.

4. startServiceByDesktopPath

Preferred way to launch desktop (KDE/Gnome/X) applications or KDE services. The application/service must have a .desktop file. It will make use of KDEinit for increased startup performance and lower memory usage. These benefits only apply to applications available as KDEinit loadable module (KLM)

5. KRun

Generic way to open documents/applications/shell commands. Uses startServiceBy.... where applicable. Offers the additional benefit of startup-notification.
KRun can start any application, from the binary or the desktop file, it will determine the mimetype of a file before running the preferred handler for it, and it can also start shell commands. This makes KRun the recommended way to run another program in KDE 2.

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tdehtmlw has been replaced with tdehtml.

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KIntegerLine, KIntLineEdit

KIntegerLine and KIntLineEdit have been replaced by KIntNumInput. The new header file is called knuminput.h.

The new KIntNumInput can have an optional slider attached, ensures that the entered value is in a given range (use MAX_INT or similar if you don't care about the range) and can maintain a descriptive label and also a unit for the edited value.

The API is almost the same and it simplifies existing code a bit, so give it a try. If you need more functionality, please contact me, Dirk A. Mueller <mueller@kde.org>.

The additional class KDoubleNumInput gives you the same look & feel, but allows you to edit floating point numbers.

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KDNDIcon, KDNDDropZone, KDNDWidget, tdecore/drag.h

KDE Drag and Drop is Dead. Long live Qt Xdnd.

Xdnd is better anyway, because it has been adopted by all the other major GUI toolkits still under active development (this precludes Motif, but maybe we can convince the lesstif guys!). Some changes are necessary to convert your old KDND-based stuff to Qt DND.

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TDEConfigBase, TDEConfig, KSimpleConfig

These classes have been largely re-implemented. The external API remains mostly the same, with the single notable change that the groupIterator and entryIterator methods have been removed and instead replaced by groupList (which returns a TQStringList of groups) and entryMap(const TQString &group) (which returns a TQMap of entries in the specified group). This is due to internal changes in TDEConfig which would make providing iterators possibly rather difficult.

Much more extensive documentation on the TDEConfig and friends API can be found in the kdoc generated documentation from the header files, and in tdecore/KCONFIG_DESIGN.

To use the new iterator, you will probably want to do something like this:

  TQMap<TQString, TQString> tmpMap = config-<entryMap(myGroup);
  TQMap<TQString, TQString>::Iterator aIt(tmpMap.begin());

  for (; aIt != tmpMap.end(); ++aIt) {
   // body here.  Access iterator key as aIt.key(),
   // data as *aIt.

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libkfm has disappeared

Lots of other functionalities have been taken out of kfm, some being now in libtdeio, some in libkonq.

Replacement table :

KFM::download -> TDEIO::NetAccess::download (tdelibs/tdeio/netaccess.h)
KFM::removeTempFile -> TDEIO::NetAccess::removeTempFile
refreshDesktop, sortDesktop, selectRootIcons : removed; kdesktop handles it
KFM::configure -> see konqueror DCOP interface
KFM::openURL -> "(void) new KRun (url)" (tdelibs/tdeio/krun.h)
KFM::refreshDirectory -> not needed anymore since konqy/kdesktop use KDirWatch
KFM::openProperties -> "(void) new KPropertiesDialog (url)" (tdelibs/tdefile/kpropsdlg.h)
KFM::exec -> "(void) new KRun (url)" (tdelibs/tdeio/krun.h)
KFM::copy, KFM::move -> TDEIO::Job (async, see tdeio/job.h)
or TDEIO::NetAccess (sync, see tdeio/netaccess.h)
DlgLocation -> Use KLineEditDlg (tdeui/klineeditdlg.h) instead

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KDialog is no longer defined in kwizard.h. Include kdialog.h instead.

Note that the best way to write new dialogs is to use KDialogBase (see kdialogbase.h)

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The kcharsets class has been completely rewritten, and most of it has vanished, since support for it moved to Qt.

Most applications will only need to replace kapp->getKCharsets() with TDEGlobal::charsets().

For conversion of various input formats to QStrings, please have a look at TQTextCodec and classes derived from it.

Character entities are now converted from and to QChars. The name has changed from convertTag to fromEntity and toEntity.

To get a font, which can display a certain charset (if such a font exists), you can use the KCharsets::setQFont methods. Input is a font and a charset. Kcharsets tries to find an output font, which matches the input font most closely, but can display the given charset.

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KWizard, KNoteBook

KWizard is based on TQWizard now. The API has changed. Consult Qt's documentation and tdelibs/kdetest/kwizardtest.cpp for an example use.

KNoteBook (deeply entwined with the former KWizard) has been removed until someone is willing to port it to work with the new wizard. If you want to use it you'll find the necessary files in tdegraphics/kiconedit.

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KSpinBox, KNumericSpinBox

These classes have been replaced by TQSpinBox. API is almost the same HINTS:

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TDEClipboard has been removed. In case you've been using TDEClipboard, QClipboard is the way to go now, as it has all the functionality the K version had, and more.

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KPanner, KNewPanner

KPanner and KNewPanner have been removed. TQSplitter does everything KPanner did and more. The api is similar, but not compatible. Basically to set it up so that you have a vertical splitter between a listbox, a listview and multi line editor, you would do something like this:

TQSplitter *split = new TQSplitter( parent );
TQListBox *lb = new TQListBox( split );
TDEListView *lv = new TDEListView( split );
TQMultiLineEdit *ed = new TQMultiLineEdit( split );
As you can see you are not limited to two children. Additionally, you do not have to call activate when you are done, and opaque resizing is possible if you call setOpaqueResize(true).

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KTreeList, KTreeListItem

Use TDEListView, TQListViewItem instead. API is almost the same, you only need to add a Column (TDEListView::addColum) before TDEListView is useable.

TDEListView has no addChild(), insertItem() and removeItem() calls. Inserting a root item is done by constructing a TQListViewItem with the TDEListView passed as the parent widget. adding a child item is done by constructing a TQListViewItem with the parent item as parameter. removeItem() should be replaced by delete <pointer to item>.

The root items are not shown in a tree fashion by default. to get this, use TDEListView::setDecorativeRoot(true).

Expanding and collapsing can by done by using TQListViewItem::setOpen(bool).

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KMsgBox has been superseded by TQMessageBox. Which has been superseded by KMessageBox.

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KCombo has been removed. Use KComboBox instead, it is completely compatible with the old KCombo API. The method that you may have problems with is the old KCombo::setText. This has been renamed to KComboBox::setEditText.

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KQuickHelp, the "super-tooltip" widget, has been replaced by TQWhatsThis. It provides a compatible API and almost the same look and feel, in addition to some new functionality.

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Instead of old KPixmap::gradientFill, use:

KPixmapEffect::gradient(KPixmap&, TQColor, TQColor, enum KPixmapEffect::GradientType, int)


pix.gradientFill(ca, cb, direction, ncols)

becomes, for direction == true :

KPixmapEffect::gradient(pix, ca, cb, KPixmapEffect::VerticalGradient, ncols)

There are now:

Gradients. See tdelibs/kdetest/kgradienttest & kunbalancedgradienttest for information on how they actually look.

Look further in this document for other info about pixmap effect code reorganization (essentially, all effects are now in libtdeui.so: gradient(), unbalancedGradient(), hash(), desaturate(), pattern(), fade(), blend() etc.

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This widget has been replaced by the almighty TDEListView. Everything said about KTreeList could be repeated here. The good thing is, that you now can combine TreeView's and normal Tablists without problems.

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TDEToolBarButton & TDERadioGroup

If you need to do anything with TDEToolBarButton you now need to include <tdetoolbarbutton.h> TDERadioGroup has been renamed to TDEToolBarRadioGroup and requires you to include <tdetoolbarradiogroup.h>

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The functions keyToString() and stringToKey() which were previously declared globally in tdeaccel.h are now static methods in TDEAccel.

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kstring.h / KString

The KString class is obsolete and is not defined in kstring.h anymore. The header file only existed for compatibility reasons. The file has been removed completely, use TQString instead. (mirko@kde.org)

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ktopwidget.h / KTopWidget

TDEMainWindow replaces this class completely. ktopwidget.h does not exist in KDE 2. (mirko@kde.org)

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kbutton.h / KButton

Since Qt 2.0, the class TQToolButton provides the functionality of buttons that raise when the mouse is moved over them, so there is no reason to have a class providing the same feature in KDE libs. All occurrences of KButton in the KDE CVS have been replaced by QToolButtons, but for applications not in the CVS it has to be done by the respective developer. (mirko@kde.org)

kbuttonbox.h / KButtonBox

KButtonBox::Orientation has been removed in favor of Qt::Orientation.

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kcolorgroup.h / KColorGroup

KColorGroup was not used in sources in the KDE CVS, and its functionality is provided by Qt. It has been removed. (mirko@kde.org)

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kled.h, kledlamp.h / KLed, KLedLamp

There where two different classes for showing an LED lamp. Both are merged to the KLed class, but THE USER INTERFACE IS DIFFERENT, as both where more or less broken.

Please adjust your code accordingly.

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KDockWidget inherits form TDEMainWindow instead of KTMainWindow now. See KTMainWindow for more details.

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KPixmap, KPixmapEffect

KPixmap::gradientFill, KPixmap::patternFill, KPixmap::tile and KPixmap::mapFill have been moved to KPixmapEffect, which is now part of libtdeui.

KPixmap::tile() has been renamed to KPixmapEffects::createTile().

Dirk A. Mueller <mueller@kde.org>

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TDE Control Center

The format for modules for the TDE Control Center has changed quite a bit. If you want to port your module to the new schema, please consult


which explains what needs to be done.

Matthias Hoelzer-Kluepfel <hoelzer@kde.org>

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KWMModuleApplication libtdeui/kwmmapp.h

The KWMModuleApplication has been removed. Instead, use the class KWinModule in libtdecore. The API is a bit cleaner but very similar, so you will feel comfortable immediately. One of the advantages of KWinModule is that it doesn't require a special TDEApplication subclass. This lead to many problems and misunderstandings in the past. KWinModule is now just an object that emits fancy signals (and provides some useful lists, like the list of all managed windows). (ettrich@kde.org)

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Use kdDebug, kdWarning, kdError, kdFatal to log debug output, warnings and errors in a very flexible way. kdebug has been improved, and the API simplified. tdesdk/scripts/kDebug2kdDebug.sh provides a script for automating the conversion. Note that enabling/disabling debug output can now be done with kdebugdialog, which can be found in tdebase. The hidden dialog on C+S+F12 no longer exists.

Also, note that tqDebug and fprintf aren't disabled by -DNDEBUG, whereas kdDebug is. One more reason to use kdDebug ! (faure@kde.org)

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KFileDialog - General Stuff

The new (rewritten) KFileDialog (KFD) is a lot more like the new QFileDialog but still looks quite different. Normally you may want to use the static methods provided for convenience (getOpenFileName and getSaveFileName). If you need special features you can configure the dialog extensively. Just create an object and use the different methods.

Werner Trobin <wtrobin@carinthia.com>

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KFileDialog - Preview Mode

There is also a new preview mode which is quite different to the one we had in the KDE 1.x KFD. There are no preview modules you have to register but there is a single method you can use to set a preview widget. This widget has to inherit TQWidget and you have to implement a slot (showPreview(const KURL &)) in this class. This slot is called each time the selected file/dir changes. In this slot you have to react appropriate (i.e. show the preview :). The easiest way this can be done is to derive your class from TQWidgetStack and add a Object (derived from TQWidget) for each file type. In the showPreview method you just raise the matching widget. If you can't find an appropriate widget just hide() the widget stack.

If you need some "inspiration" on how that could be done, please have a look at koffice/lib/kofficecore/koFilterManager.cc (PreviewStack).

Werner Trobin <wtrobin@carinthia.com>

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Image effects

The kFSDither class is now gone. Its functionality was moved to KImageEffect::dither(). Whereas before, you would done:

  kFSDither dither(palette, ncols);
  image = dither.dither(image);

Now do:
  KImageEffect::dither(image, palette, ncols);

Kurt Granroth <granroth@kde.org>

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KAudio (kaudio.h)

The KAudio class no longer exists. Here are your options for porting.

Stefan Westerfeld stefan@space.twc.de

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KImageIO (kimgio.h)

KImageIO has moved from 'kimgio.h' to 'kimageio.h'. LIB_KIMGIO does no longer exists, you need to link against LIB_KSYCOCA instead.

kimgioRegister() has been replaced by KImageIO::registerFormats().

Waldo Bastian bastian@kde.org

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