Development/Tutorials/Using KActions/KF5: Difference between revisions

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(Rough draft)
 
m (Remove use of ECM_KDE_MODULE_DIR, part of ECM_MODULE_PATH)
 
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name=How To Use KActions and XMLGUI|
name=How To Use KActions and XMLGUI|


pre=[[Development/Tutorials/Using_KXmlGuiWindow|Tutorial 2 - KXmlGuiWindow]], Basic XML knowledge|
pre=[[Development/Tutorials/Using_KXmlGuiWindow/KF5|Tutorial 2 - KXmlGuiWindow]], Basic XML knowledge|


next=[[Development/Tutorials/Saving_and_loading|Tutorial 4 - Saving and loading]]|  
next=[[Development/Tutorials/Saving_and_loading/KF5|Tutorial 4 - Saving and loading]]|  


reading=None
reading=None
Line 14: Line 14:


==Abstract==
==Abstract==
This tutorial introduces the concept of actions. Actions are a unified way of supplying the user with ways to interact with your program.


Rough draft of port to KDE Frameworks 5.
For example, if we wanted to let the user of [[Development/Tutorials/Using_KXmlGuiWindow|Tutorial 2 ]] clear the text box by clicking a button in the toolbar, from an option in the File menu or through a keyboard shortcut, it could all be done with one [http://doc.qt.io/qt-5/qaction.html QAction].
 
[[image:tutorial3-kf5.png|frame|center]]


==KAction==
==KAction==


KAction has been deprecated in favor of [http://doc.qt.io/qt-5/qaction.html QAction] and [http://doc.qt.io/qt-5/qwidgetaction.html QWidgetAction].
A [http://doc.qt.io/qt-5/qaction.html QAction] is an object which contains all the information about the icon and shortcuts that is associated with a certain action. The action is then connected to a [http://doc.qt.io/qt-5/signalsandslots.html slot] which carries out the work of your action.


==The Code==
==The Code==
Line 38: Line 41:
{
{
     QApplication app(argc, argv);
     QApplication app(argc, argv);
   
     KLocalizedString::setApplicationDomain("tutorial3");
     KLocalizedString::setApplicationDomain("tutorial1");
      
      
     KAboutData aboutData(
     KAboutData aboutData(
Line 49: Line 51:
                         QStringLiteral("1.0"),
                         QStringLiteral("1.0"),
                         // Short description of what the app does. (shortDescription)
                         // Short description of what the app does. (shortDescription)
                         i18n("A simple text area"),
                         i18n("A simple text area using KAction etc."),
                         // The license this code is released under
                         // The license this code is released under
                         KAboutLicense::GPL,
                         KAboutLicense::GPL,
Line 62: Line 64:
                         // (bugsEmailAddress = QLatin1String("[email protected]")
                         // (bugsEmailAddress = QLatin1String("[email protected]")
                         QStringLiteral("[email protected]"));
                         QStringLiteral("[email protected]"));
   
     aboutData.addAuthor(i18n("Name"), i18n("Task"), QStringLiteral("[email protected]"),
     aboutData.addAuthor(i18n("Name"), i18n("Task"), QStringLiteral("[email protected]"),
                         QStringLiteral("http://your.website.com"), QStringLiteral("OSC Username"));
                         QStringLiteral("http://your.website.com"), QStringLiteral("OSC Username"));
   
     KAboutData::setApplicationData(aboutData);
     KAboutData::setApplicationData(aboutData);
   
   
Line 81: Line 81:
}
}
</syntaxhighlight>
</syntaxhighlight>
This time, very little has changed in <tt>main.cpp</tt>, only the KAboutData constructor has been updated to show that we are now on tutorial 3.


===mainwindow.h===
===mainwindow.h===
Line 103: Line 104:
#endif
#endif
</syntaxhighlight>
</syntaxhighlight>
Only a function <tt>void setupActions()</tt> has been added which will do all the work setting up the QActions.


===mainwindow.cpp===
===mainwindow.cpp===
<syntaxhighlight lang="cpp-qt">
<syntaxhighlight lang="cpp-qt">
// 1
#include <QApplication>
#include <QApplication>
// 2
#include <QAction>
#include <QAction>


#include <KTextEdit>
#include <KTextEdit>
// 3
#include <KLocalizedString>
#include <KLocalizedString>
#include <KActionCollection>
#include <KActionCollection>
Line 131: Line 130:
     QAction* clearAction = new QAction(this);
     QAction* clearAction = new QAction(this);
     clearAction->setText(i18n("&Clear"));
     clearAction->setText(i18n("&Clear"));
    // 4
     clearAction->setIcon(QIcon::fromTheme("document-new"));
     clearAction->setIcon(QIcon::fromTheme("document-new"));
    // 5
     actionCollection()->setDefaultShortcut(clearAction, Qt::CTRL + Qt::Key_W);
     actionCollection()->setDefaultShortcut(clearAction, Qt::CTRL + Qt::Key_W);
     actionCollection()->addAction("clear", clearAction);
     actionCollection()->addAction("clear", clearAction);
     connect(clearAction, SIGNAL(triggered(bool)), textArea, SLOT(clear()));
     connect(clearAction, SIGNAL(triggered(bool)), textArea, SLOT(clear()));
      
      
    // 6
     KStandardAction::quit(qApp, SLOT(quit()), actionCollection());
     KStandardAction::quit(qApp, SLOT(quit()), actionCollection());
      
      
Line 145: Line 141:
</syntaxhighlight>
</syntaxhighlight>


===Notes===
==Explanation==
# No more KApplication - https://community.kde.org/Frameworks/Porting_Notes#Application
 
# Replace KAction with QAction and/or QWidgetAction - https://community.kde.org/Frameworks/Porting_Notes#Action
This builds upon the KXmlGuiWindow code from [[Development/Tutorials/Using_KXmlGuiWindow/KF5|Tutorial 2]]. Most of the changes are to <tt>mainwindow.cpp</tt>, an important structural change being that the constructor for MainWindow now calls <tt>setupActions()</tt> instead of <tt>setupGUI()</tt>. <tt>setupActions()</tt> is where the new QAction code goes before finally calling <tt>setupGUI()</tt> itself.
# KLocale is deprecated is kdelibs4support, use KLocalizedString for i18n() - https://community.kde.org/Frameworks/Porting_Notes#Localization
 
# KIcon has been deprecated, use QIcon https://community.kde.org/Frameworks/Porting_Notes#General_2
===Creating the QAction object===
# Warning message: Shortcut for action  "clear" "&Clear" set with QAction::setShortcut()! Use KActionCollection::setDefaultShortcut(s) instead.
The QAction is built up in a number of steps. The first is including the <tt>QAction</tt> header and then creating the QAction:
# Since KApplication is gone, we can't use kapp anymore. Use [http://doc.qt.io/qt-5/qapplication.html#qApp qApp] macro instead.
<syntaxhighlight lang="cpp-qt">
#include <QAction>
...
QAction* clearAction = new QAction(this);
</syntaxhighlight>
This creates a new QAction called <tt>clearAction</tt>.
 
===Setting QAction Properties===
====Text====
Now that we have our QAction object, we can start setting its properties. The following code sets the text that will be displayed in the menu and under the <tt>QAction</tt>'s icon in the toolbar.
<syntaxhighlight lang="cpp-qt">
clearAction->setText(i18n("&Clear"));
</syntaxhighlight>
Note that the text is passed through the <tt>i18n()</tt> function; this is necessary for the UI to be translatable (more information on this can be found in the [[Development/Tutorials/Localization/i18n|i18n tutorial]]).
 
The text of the action should contain a <tt>&</tt> because that makes it easier to translate in non-latin1 languages. In Japanese, the translation might be <tt>ソース(&S)</tt> and without the <tt>&</tt> in the english text the translators cannot know if they have to add a <tt>&</tt> or not.
 
====Icon====
If the action is going to be displayed in a toolbar, it is nice to have an icon depicting the action. The following code sets the icon to the standard the <tt>document-new</tt> icon through the use of the <tt>setIcon()</tt> function:
<syntaxhighlight lang="cpp-qt">
clearAction->setIcon(QIcon::fromTheme("document-new"));
</syntaxhighlight>
 
====Keyboard Shortcut====
Setting a keyboard shortcut to perform our action is equally simple:
<syntaxhighlight lang="cpp-qt">
actionCollection()->setDefaultShortcut(clearAction, Qt::CTRL + Qt::Key_W);
</syntaxhighlight>
This associates Ctrl+W with the QAction.
 
===Adding to the Collection===
In order for the action to be accessed by the XMLGUI framework (explained in depth later) it must be added to the application's ''action collection''. The action collection is accessed via the <tt>actionCollection()</tt> function like this:
<syntaxhighlight lang="cpp-qt">
actionCollection()->addAction("clear", clearAction);
</syntaxhighlight>
Here, the <tt>clearAction</tt> QAction is added to the collection and given a name of ''clear''. This name (''clear'') is used by the XMLGUI framework to refer to the action, ergo, it should not be localized, since it is used internally only.
 
====Connecting the action====
Now that the action is fully set up, it needs to be connected to something useful. In this case (because we want to clear the text area), we connect our action to the <tt>clear()</tt> action belonging to a KTextEdit (which, unsurprisingly, clears the KTextEdit)
<syntaxhighlight lang="cpp-qt">
connect( clearAction, SIGNAL( triggered(bool) ),
        textArea, SLOT( clear() ) );
</syntaxhighlight>
 
===KStandardAction===
 
For actions which would likely appear in almost every KDE application such as 'quit', 'save', and 'load' there are pre-created convenience QActions, accessed through {{kde|KStandardAction}}.
 
They are very simple to use. Once the library has been included (<tt>#include <KStandardAction></tt>), simply supply it with what you want the function to do and which QActionCollection to add it to. For example:
<syntaxhighlight lang="cpp-qt">
KStandardAction::quit(qApp, SLOT(quit()), actionCollection());
</syntaxhighlight>
Here we call the QApplicaton's [http://doc.qt.io/qt-5/qapplication.html#quit quit] method whenever the KStandardAction quit is triggered. We are able to access that QApplication method via the [http://doc.qt.io/qt-5/qapplication.html#qApp qApp] macro.
 
In the end, this creates a QAction with the correct icon, text and shortcut and even adds it to the File menu.
 
==Adding the action to menus and toolbars==
At the moment, the new "Clear" action has been created but it hasn't been associated with any menus or toolbars. This is done with a KDE technology called XMLGUI, which does nice things like movable toolbars for you.
 
==Defining your own help menu==
The help menu is god-given, that is why all KDE help menus look the same. If you want to create your own help menu, search for the explanation around showAboutApplication() in from the {{class|KHelpMenu}} class in XMLGUI.
 
==XMLGUI==
 
The <tt>setupGUI()</tt> function in {{class|KXmlGuiWindow}} depends on the XMLGUI system to construct the GUI, which XMLGUI does by parsing an XML file description of the interface.
 
The rule for naming this XML file is <tt>appnameui.rc</tt>, where <tt>appname</tt> is the name you set in {{class|KAboutData}} (in this case, ''tutorial3''). So in our example, the file is called <tt>tutorial3ui.rc</tt>, and is located in the build directory. Where the file will ultimately be placed is handled by CMake.


==appnameui.rc file==
==appnameui.rc file==
Since the description of the UI is defined with XML, the layout must follow strict rules. This tutorial will not go into great depth on this topic, but for more information, see the [[Development/Architecture/KDE4/XMLGUI_Technology|detailed XMLGUI page]].


===tutorial3ui.rc===
===tutorial3ui.rc===
Line 182: Line 246:
</gui>
</gui>
</syntaxhighlight>
</syntaxhighlight>
The <tt><Toolbar></tt> tag allows you to describe the toolbar, which is the bar across the top of the window normally with icons. Here it is given the unique name ''mainToolBar'' and its user visible name set to ''Main Toolbar'' using the <tt><text></tt> tag. The clear action is added to the toolbar using the <tt><Action></tt> tag, the name parameter in this tag being the string that was passed to the KActionCollection with <tt>addAction()</tt> in <tt>mainwindow.cpp</tt>.
Besides having the action in the toolbar, it can also be added to the menubar. Here the action is being added to the ''File'' menu of the <tt>MenuBar</tt> the same way it was added to the toolbar.
Change the 'version' attribute of the <tt><nowiki><gui></nowiki></tt> tag if you changed .rc file since the last install to force a system cache update. Be sure it is an integer, if you use a decimal value, it will not work, but will not notify that it didn't. '
{{Warning|The version attribute must be an integer number, if you type in version<nowiki>=</nowiki>"1.2" it will dispose of your kittens  (but not eat them).}}
Some notes on the interaction between code and the .rc file: Menus appear automatically and should have a <tt><nowiki><text/></nowiki></tt> child tag unless they refer to standard menus. Actions need to be created manually and inserted into the actionCollection() using the name in the .rc file. Actions can be hidden or disabled, whereas menus can't.


==CMake==
==CMake==
Finally, the <tt>tutorial3ui.rc</tt> needs to go somewhere where KDE can find it (can't just leave it in the source directory!). '''This means the project needs to be installed somewhere''', unlike in the previous tutorials.


===CMakeLists.txt===
===CMakeLists.txt===
Line 194: Line 269:


find_package(ECM 1.0.0 REQUIRED NO_MODULE)
find_package(ECM 1.0.0 REQUIRED NO_MODULE)
set(CMAKE_MODULE_PATH ${ECM_MODULE_PATH} ${ECM_KDE_MODULE_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/cmake)
set(CMAKE_MODULE_PATH ${ECM_MODULE_PATH} ${CMAKE_CURRENT_SOURCE_DIR}/cmake)


include(KDEInstallDirs)
include(KDEInstallDirs)
Line 201: Line 276:
include(FeatureSummary)
include(FeatureSummary)


# Find Qt modules
find_package(Qt5 ${QT_MIN_VERSION} CONFIG REQUIRED COMPONENTS  
find_package(Qt5 ${QT_MIN_VERSION} CONFIG REQUIRED COMPONENTS  
     Core    # QCommandLineParser, QStringLiteral
     Core    # QCommandLineParser, QStringLiteral
Line 207: Line 281:
)
)


# Find KDE modules
find_package(KF5 ${KF5_MIN_VERSION} REQUIRED COMPONENTS
find_package(KF5 ${KF5_MIN_VERSION} REQUIRED COMPONENTS
     CoreAddons      # KAboutData
     CoreAddons      # KAboutData
Line 221: Line 294:
set(tutorial3_SRCS main.cpp mainwindow.cpp)
set(tutorial3_SRCS main.cpp mainwindow.cpp)


# just plain add_executable
add_executable(tutorial3 ${tutorial3_SRCS})
add_executable(tutorial3 ${tutorial3_SRCS})


# module-based linking
target_link_libraries(tutorial3
target_link_libraries(tutorial3
     Qt5::Widgets
     Qt5::Widgets
Line 235: Line 306:


install(TARGETS tutorial3  ${INSTALL_TARGETS_DEFAULT_ARGS})
install(TARGETS tutorial3  ${INSTALL_TARGETS_DEFAULT_ARGS})
# 1
install(FILES tutorial3ui.rc DESTINATION ${KXMLGUI_INSTALL_DIR}/tutorial3)
install(FILES tutorial3ui.rc DESTINATION ${KXMLGUI_INSTALL_DIR}/tutorial3)
</syntaxhighlight>
</syntaxhighlight>


===Notes===
This file is almost identical to the one for tutorial2, but with two extra lines at the end that describe where the files are to be installed. Firstly, the <tt>tutorial3</tt> target is installed to the <tt>INSTALL_TARGETS_DEFAULT_ARGS</tt> then the <tt>tutorial3ui.rc</tt> file that describes the layout of the user interface is installed to the application's data directory under <tt>KXMLGUI_INSTALL_DIR</tt>.
# .ui files now installed to {KXMLGUI_INSTALL_DIR - https://community.kde.org/Frameworks/Porting_Notes#General
 
===Make, Install And Run===
This is probably the trickiest part. Where you install the files, especially <tt>tutorial3ui.rc</tt> is important. Normally, you'd want to install it where KDE software is installed by your distribution, which is usually under {{path|/usr}}. That, however, would require root/admin access and If you don't have that, you can install it to a folder in your home directory.
 
To tell CMake where to install the program, set the <tt>DCMAKE_INSTALL_PREFIX</tt> switch. You probably just want to install it somewhere local for testing (it's probably a bit silly to go to the effort of installing these tutorials to your KDE directory), so the following might be appropriate:
<syntaxhighlight lang="bash">
mkdir build && cd build
cmake .. -DCMAKE_INSTALL_PREFIX=$HOME
make install
</syntaxhighlight>
which will create a KDE-like directory structure in your user's home directory. Specifically, it will create the directories {{path|$HOME/bin/}} and {{path|$HOME/share/}} and will install the executable to {{path|$HOME/bin/tutorial3}} and the <tt>tutorial3ui.rc</tt> file to {{path|$HOME/share/kxmlgui/tutorial3/tutorial3ui.rc}}.
 
However, to be able to run the program properly, you will need to let the system know where the XMLGUI file is. Since we installed it in a nonstandard location, we'll have to explicitly to do so every time. The following command would suffice:
<syntaxhighlight lang="bash">
XDG_DATA_DIRS=$HOME/share:$XDG_DATA_DIRS $HOME/bin/tutorial3
</syntaxhighlight>
This temporarily adds (prepends) the newly created "share" location to <tt>XDG_DATA_DIRS</tt>, the standard path for application data files.
 
==Moving On==
Now you can move on to [[Development/Tutorials/Saving_and_loading/KF5|saving and loading]].
 
Or you can learn [[Development/Tutorial/Icons|how to add icons to your application]].
 
Or you can learn [[Development/Tutorials/Desktop_File|how to place your application in the K-Menu using .desktop files]].
 
[[Category:C++]]

Latest revision as of 18:01, 18 April 2020

How To Use KActions and XMLGUI
Tutorial Series   Beginner Tutorial
Previous   Tutorial 2 - KXmlGuiWindow, Basic XML knowledge
What's Next   Tutorial 4 - Saving and loading
Further Reading   None

Abstract

This tutorial introduces the concept of actions. Actions are a unified way of supplying the user with ways to interact with your program.

For example, if we wanted to let the user of Tutorial 2 clear the text box by clicking a button in the toolbar, from an option in the File menu or through a keyboard shortcut, it could all be done with one QAction.

KAction

A QAction is an object which contains all the information about the icon and shortcuts that is associated with a certain action. The action is then connected to a slot which carries out the work of your action.

The Code

main.cpp

#include <cstdlib>
 
#include <QApplication>
#include <QCommandLineParser>

#include <KAboutData>
#include <KLocalizedString>

#include "mainwindow.h"
 
int main (int argc, char *argv[])
{
    QApplication app(argc, argv);
    KLocalizedString::setApplicationDomain("tutorial3");
    
    KAboutData aboutData(
                         // The program name used internally. (componentName)
                         QStringLiteral("tutorial3"),
                         // A displayable program name string. (displayName)
                         i18n("Tutorial 3"),
                         // The program version string. (version)
                         QStringLiteral("1.0"),
                         // Short description of what the app does. (shortDescription)
                         i18n("A simple text area using KAction etc."),
                         // The license this code is released under
                         KAboutLicense::GPL,
                         // Copyright Statement (copyrightStatement = QString())
                         i18n("(c) 2015"),
                         // Optional text shown in the About box.
                         // Can contain any information desired. (otherText)
                         i18n("Some text..."),
                         // The program homepage string. (homePageAddress = QString())
                         QStringLiteral("http://example.com/"),
                         // The bug report email address
                         // (bugsEmailAddress = QLatin1String("[email protected]")
                         QStringLiteral("[email protected]"));
    aboutData.addAuthor(i18n("Name"), i18n("Task"), QStringLiteral("[email protected]"),
                        QStringLiteral("http://your.website.com"), QStringLiteral("OSC Username"));
    KAboutData::setApplicationData(aboutData);
 
    QCommandLineParser parser;
    parser.addHelpOption();
    parser.addVersionOption();
    aboutData.setupCommandLine(&parser);
    parser.process(app);
    aboutData.processCommandLine(&parser);
    
    MainWindow* window = new MainWindow();
    window->show();
    
    return app.exec();
}

This time, very little has changed in main.cpp, only the KAboutData constructor has been updated to show that we are now on tutorial 3.

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H
 
#include <KXmlGuiWindow>

class KTextEdit;
 
class MainWindow : public KXmlGuiWindow
{
  public:
    MainWindow(QWidget *parent=0);
 
  private:
    KTextEdit* textArea;
    void setupActions();
};
 
#endif

Only a function void setupActions() has been added which will do all the work setting up the QActions.

mainwindow.cpp

#include <QApplication>
#include <QAction>

#include <KTextEdit>
#include <KLocalizedString>
#include <KActionCollection>
#include <KStandardAction>

#include "mainwindow.h"

MainWindow::MainWindow(QWidget *parent) : KXmlGuiWindow(parent)
{
  textArea = new KTextEdit();
  setCentralWidget(textArea);
  
  setupActions();
}

void MainWindow::setupActions()
{
    QAction* clearAction = new QAction(this);
    clearAction->setText(i18n("&Clear"));
    clearAction->setIcon(QIcon::fromTheme("document-new"));
    actionCollection()->setDefaultShortcut(clearAction, Qt::CTRL + Qt::Key_W);
    actionCollection()->addAction("clear", clearAction);
    connect(clearAction, SIGNAL(triggered(bool)), textArea, SLOT(clear()));
    
    KStandardAction::quit(qApp, SLOT(quit()), actionCollection());
    
    setupGUI(Default, "tutorial3ui.rc");
}

Explanation

This builds upon the KXmlGuiWindow code from Tutorial 2. Most of the changes are to mainwindow.cpp, an important structural change being that the constructor for MainWindow now calls setupActions() instead of setupGUI(). setupActions() is where the new QAction code goes before finally calling setupGUI() itself.

Creating the QAction object

The QAction is built up in a number of steps. The first is including the QAction header and then creating the QAction:

#include <QAction>
...
QAction* clearAction = new QAction(this);

This creates a new QAction called clearAction.

Setting QAction Properties

Text

Now that we have our QAction object, we can start setting its properties. The following code sets the text that will be displayed in the menu and under the QAction's icon in the toolbar.

clearAction->setText(i18n("&Clear"));

Note that the text is passed through the i18n() function; this is necessary for the UI to be translatable (more information on this can be found in the i18n tutorial).

The text of the action should contain a & because that makes it easier to translate in non-latin1 languages. In Japanese, the translation might be ソース(&S) and without the & in the english text the translators cannot know if they have to add a & or not.

Icon

If the action is going to be displayed in a toolbar, it is nice to have an icon depicting the action. The following code sets the icon to the standard the document-new icon through the use of the setIcon() function:

clearAction->setIcon(QIcon::fromTheme("document-new"));

Keyboard Shortcut

Setting a keyboard shortcut to perform our action is equally simple:

actionCollection()->setDefaultShortcut(clearAction, Qt::CTRL + Qt::Key_W);

This associates Ctrl+W with the QAction.

Adding to the Collection

In order for the action to be accessed by the XMLGUI framework (explained in depth later) it must be added to the application's action collection. The action collection is accessed via the actionCollection() function like this:

actionCollection()->addAction("clear", clearAction);

Here, the clearAction QAction is added to the collection and given a name of clear. This name (clear) is used by the XMLGUI framework to refer to the action, ergo, it should not be localized, since it is used internally only.

Connecting the action

Now that the action is fully set up, it needs to be connected to something useful. In this case (because we want to clear the text area), we connect our action to the clear() action belonging to a KTextEdit (which, unsurprisingly, clears the KTextEdit)

connect( clearAction, SIGNAL( triggered(bool) ), 
         textArea, SLOT( clear() ) );

KStandardAction

For actions which would likely appear in almost every KDE application such as 'quit', 'save', and 'load' there are pre-created convenience QActions, accessed through Template:Kde.

They are very simple to use. Once the library has been included (#include <KStandardAction>), simply supply it with what you want the function to do and which QActionCollection to add it to. For example:

KStandardAction::quit(qApp, SLOT(quit()), actionCollection());

Here we call the QApplicaton's quit method whenever the KStandardAction quit is triggered. We are able to access that QApplication method via the qApp macro.

In the end, this creates a QAction with the correct icon, text and shortcut and even adds it to the File menu.

Adding the action to menus and toolbars

At the moment, the new "Clear" action has been created but it hasn't been associated with any menus or toolbars. This is done with a KDE technology called XMLGUI, which does nice things like movable toolbars for you.

Defining your own help menu

The help menu is god-given, that is why all KDE help menus look the same. If you want to create your own help menu, search for the explanation around showAboutApplication() in from the KHelpMenu class in XMLGUI.

XMLGUI

The setupGUI() function in KXmlGuiWindow depends on the XMLGUI system to construct the GUI, which XMLGUI does by parsing an XML file description of the interface.

The rule for naming this XML file is appnameui.rc, where appname is the name you set in KAboutData (in this case, tutorial3). So in our example, the file is called tutorial3ui.rc, and is located in the build directory. Where the file will ultimately be placed is handled by CMake.

appnameui.rc file

Since the description of the UI is defined with XML, the layout must follow strict rules. This tutorial will not go into great depth on this topic, but for more information, see the detailed XMLGUI page.

tutorial3ui.rc

<?xml version="1.0" encoding="UTF-8"?>
<gui name="tutorial3"
     version="1"
     xmlns="http://www.kde.org/standards/kxmlgui/1.0"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.kde.org/standards/kxmlgui/1.0
                         http://www.kde.org/standards/kxmlgui/1.0/kxmlgui.xsd" >
 
  <MenuBar>
    <Menu name="file" >
      <Action name="clear" />
    </Menu>
    <Menu >
      <text>A&amp;nother Menu</text>
      <Action name="clear" />
    </Menu >
  </MenuBar>
 
  <ToolBar name="mainToolBar" >
    <text>Main Toolbar</text>
    <Action name="clear" />
  </ToolBar>
 
</gui>

The <Toolbar> tag allows you to describe the toolbar, which is the bar across the top of the window normally with icons. Here it is given the unique name mainToolBar and its user visible name set to Main Toolbar using the <text> tag. The clear action is added to the toolbar using the <Action> tag, the name parameter in this tag being the string that was passed to the KActionCollection with addAction() in mainwindow.cpp.

Besides having the action in the toolbar, it can also be added to the menubar. Here the action is being added to the File menu of the MenuBar the same way it was added to the toolbar.

Change the 'version' attribute of the <gui> tag if you changed .rc file since the last install to force a system cache update. Be sure it is an integer, if you use a decimal value, it will not work, but will not notify that it didn't. '

Warning
The version attribute must be an integer number, if you type in version="1.2" it will dispose of your kittens (but not eat them).


Some notes on the interaction between code and the .rc file: Menus appear automatically and should have a <text/> child tag unless they refer to standard menus. Actions need to be created manually and inserted into the actionCollection() using the name in the .rc file. Actions can be hidden or disabled, whereas menus can't.

CMake

Finally, the tutorial3ui.rc needs to go somewhere where KDE can find it (can't just leave it in the source directory!). This means the project needs to be installed somewhere, unlike in the previous tutorials.

CMakeLists.txt

project (tutorial3)

cmake_minimum_required(VERSION 2.8.12 FATAL_ERROR)
set(QT_MIN_VERSION "5.3.0")
set(KF5_MIN_VERSION "5.2.0")

find_package(ECM 1.0.0 REQUIRED NO_MODULE)
set(CMAKE_MODULE_PATH ${ECM_MODULE_PATH} ${CMAKE_CURRENT_SOURCE_DIR}/cmake)

include(KDEInstallDirs)
include(KDECMakeSettings)
include(KDECompilerSettings)
include(FeatureSummary)

find_package(Qt5 ${QT_MIN_VERSION} CONFIG REQUIRED COMPONENTS 
    Core    # QCommandLineParser, QStringLiteral
    Widgets # QApplication, QAction
)

find_package(KF5 ${KF5_MIN_VERSION} REQUIRED COMPONENTS
    CoreAddons      # KAboutData
    I18n            # KLocalizedString
    XmlGui          # KXmlGuiWindow, KActionCollection
    TextWidgets     # KTextEdit
    ConfigWidgets   # KStandardActions
)
    

feature_summary(WHAT ALL INCLUDE_QUIET_PACKAGES FATAL_ON_MISSING_REQUIRED_PACKAGES)
    
set(tutorial3_SRCS main.cpp mainwindow.cpp)

add_executable(tutorial3 ${tutorial3_SRCS})

target_link_libraries(tutorial3
    Qt5::Widgets
    KF5::CoreAddons
    KF5::I18n
    KF5::XmlGui
    KF5::TextWidgets
    KF5::ConfigWidgets
)

install(TARGETS tutorial3  ${INSTALL_TARGETS_DEFAULT_ARGS})
install(FILES tutorial3ui.rc DESTINATION ${KXMLGUI_INSTALL_DIR}/tutorial3)

This file is almost identical to the one for tutorial2, but with two extra lines at the end that describe where the files are to be installed. Firstly, the tutorial3 target is installed to the INSTALL_TARGETS_DEFAULT_ARGS then the tutorial3ui.rc file that describes the layout of the user interface is installed to the application's data directory under KXMLGUI_INSTALL_DIR.

Make, Install And Run

This is probably the trickiest part. Where you install the files, especially tutorial3ui.rc is important. Normally, you'd want to install it where KDE software is installed by your distribution, which is usually under /usr. That, however, would require root/admin access and If you don't have that, you can install it to a folder in your home directory.

To tell CMake where to install the program, set the DCMAKE_INSTALL_PREFIX switch. You probably just want to install it somewhere local for testing (it's probably a bit silly to go to the effort of installing these tutorials to your KDE directory), so the following might be appropriate:

mkdir build && cd build
cmake .. -DCMAKE_INSTALL_PREFIX=$HOME
make install

which will create a KDE-like directory structure in your user's home directory. Specifically, it will create the directories $HOME/bin/ and $HOME/share/ and will install the executable to $HOME/bin/tutorial3 and the tutorial3ui.rc file to $HOME/share/kxmlgui/tutorial3/tutorial3ui.rc.

However, to be able to run the program properly, you will need to let the system know where the XMLGUI file is. Since we installed it in a nonstandard location, we'll have to explicitly to do so every time. The following command would suffice:

XDG_DATA_DIRS=$HOME/share:$XDG_DATA_DIRS $HOME/bin/tutorial3

This temporarily adds (prepends) the newly created "share" location to XDG_DATA_DIRS, the standard path for application data files.

Moving On

Now you can move on to saving and loading.

Or you can learn how to add icons to your application.

Or you can learn how to place your application in the K-Menu using .desktop files.