Setting up and getting started
Getting ready to create our first Kirigami application
Last updated
Getting ready to create our first Kirigami application
Last updated
Before getting started, we will need to install Kirigami on our machine. There are three ways to do so:
We need a C++ compiler, Qt development packages, and Kirigami. Open a terminal application and run one of the following, depending on which Linux distribution you are using:
Fedora
Further information for other distributions can be found .
If you wish to build Kirigami with Qt6, it is recommended to use instead, especially for Linux installations using Plasma 5.
KDE has a custom tool to easily build all of its libraries and programs: kdesrc-build. It can be used to build Kirigami on Linux and FreeBSD.
For this tutorial, you will need to follow the .
After that, you may simply run the following on a terminal:
After that, you may simply run the following on a terminal:
If you close your terminal, you can simply run the environment setup file again to compile your app.
While there are tools that can easily set up our files, we are going to create them manually. This will let us better understand the pieces that are going to make up our new application.
First we create our project folder (you can use the commands below). We are going to call ours kirigami-tutorial/.
Within this folder we are going to create a src/ folder and CMakeLists.txt. It is generally considered good practice to place all our main C++ code files in a src/ folder. We also put the Main.qml file in it since it will be run together with the executable.
Here's where we will be handling our application's frontend.
We then set the window's id property to "root". IDs are useful because they let us uniquely reference a component, even if we have several of the same type.
We also set the window title property to "Hello World". You'll notice that we have wrapped our "Hello World" string in a function called i18nc(), where we detail the context of the string as well as the string itself.
The line with add_subdirectory(src) points CMake to the kirigami-tutorial/src/ directory, where our source code is located.
The line with install() tells CMake where to install the desktop file.
Let's delve into the kirigami-tutorial/src/CMakeLists.txt file in there.
This file consists of five steps:
create an executable
change the executable into a QML module that accepts QML files
add C++ and QML files to the executable
link the libraries necessary for the executable to run
install the executable to the right place
Now that CMake has been taken care of, let's look at the files we are going to spend the majority of our time working with.
The file kirigami-tutorial/src/main.cpp handles the "business logic" of our application. C++ is handy because it is flexible and fast, even if it is more involved than other programming languages.
It also functions as the entrypoint to our application. The two parts of our project, the backend and the user interface, are both set up and started here.
For now, we don't need to go into too much detail regarding what our main.cpp code does, but its role will grow significantly more important once we decide to add more complex functionality to our application in the future.
For now, the part that interests us is this line:
The first argument is the URI set in kirigami-tutorial/src/CMakeLists.txt, and the second argument is the name of the QML module we want to use (Main, coming from the name of our Main.qml file, which needs to start with an uppercase letter).
We are almost at the finish line. The last thing we need to do is build and run our application. Doing so will depend on which platform you are on.
If you want kdesrc-build to handle building and installation of your project, you need to specify a custom module in your $HOME/.config/kdesrc-buildrc:
Then you can build and install it with the command:
In case you want to handle building and installation manually without kdesrc-build, you will need to specify the place where the program will be installed. To do that, we need to change directories to our kirigami-tutorial/ folder in our terminal application of choice and run the following commands:
The program will be installed to $HOME/.local/bin and its desktop entry to $HOME/.local/share/applications.
Depending on how you installed the compiler, you might need to specify a CMake Generator for the first step, depending on whether you are using Visual Studio (msvc) or MinGW (make) to compile your projects.
If Visual Studio, depending on the compiler you chose to install, it might be:
Or:
If MinGW:
In both cases, the program will be installed to C:\CraftRoot\bin.
If you ever get in doubt as to the name of the compiler that should be used in the cmake call, run:
It will list all available generators.
You can then run the kirigami-hello program with:
Voilà! Now you will see your very first Kirigami app appear before your very own eyes.
To run the new QML application in mobile mode, you can use QT_QUICK_CONTROLS_MOBILE=1:
If you have compiled the project manually with CMake and for some reason you'd like to uninstall the project, you can run:
,
KDE has a custom tool to easily install most of its libraries and programs: Craft. It can be used to install Kirigami on , , , and .
You will need to follow the . By the end of the setup, you should have run an environment setup file (craftenv.ps1 or craftenv.sh), which will give you a terminal shell where you will be compiling your Kirigami application.
If you know some Javascript, then much of QML will seem familiar to you (though it does have its own peculiarities). has an extensive amount of material on this language if you feel like trying something on your own. Over the course of these tutorials we will be focusing much of our attention on our QML code, where we can use Kirigami to get the most out of it.
For now, let's focus on Main.qml. First we a number of important modules:
, the standard library used in QML applications.
, which provides a number of standard controls we can use to make our applications interactive.
, which provides tools for placing components within the application window.
, which provides a number of components suited for creating applications that work across devices of different shapes and sizes.
We then come to our base element, , which provides some basic features needed for all Kirigami applications. This is the window that will contain each of our pages, the main sections of our UI.
functions make your app more easily translatable, as they return a version of the provided string in the user's language (as long as your app has been localised for that language). While an English user might see our window title as "Hello World", a Spanish user would see "Hola Mundo".
builds on the i18n() function by allowing developers to provide some context to translators working on the app. Here we clarify that the UI component is the title of the application window, so we have included the string "@title:window" before "Hello World". See the for more details.
We then set the first page of our page stack. Most Kirigami applications are organised as a stack of pages, each page containing related components suited to a specific task. For now, we are keeping it simple, and sticking to a single page. is an initially empty stack of pages provided by , and with pageStack.initialPage: Kirigami.Page {...} we set the first page presented upon loading the application to a . This page will contain all our content.
Finally, we include in our page a that lets us place text on our page. We use anchors.centerIn: parent to center our label horizontally and vertically within our parent element. In this case, the parent component of our label is . The last thing we need to do is set its text: text: i18n("Hello World!").
The primary purpose of is to show your app on the application launcher on Linux. Another reason to have them is to have window icons on Wayland, as they are required to tell the compositor "this window goes with this icon".
It must follow a followed by the .desktop extension such as org.kde.tutorial.desktop:
Window and taskbar icons will work in a Wayland session only if apps' desktop files are placed in ~/.local/share/applications or /usr/share/applications. To get icons working in this tutorial, either copy the app's desktop file there or switch to a development session as instructed in . Some KDE applications might have working icons if they were already installed on the system.
CMakeLists.txt files are needed to use KDE's build system of choice, . Our kirigami-tutorial/CMakeLists.txt file is going to specify some of our application's characteristics. It also includes some of the dependencies we need in order to compile our project.
The CMakeLists.txt defines how to build your projects. Most of the content here is just to bootstrap your project. You can read a line-by-line, in-depth explanation of what this CMakeLists file does .
The most important thing to keep in mind is that the C++ build dependencies of Qt and KDE Frameworks are managed with and QML runtime dependencies are managed with . You will have to modify these lines and include any additional components that you decide to use during the development of your application.
Next time you need to add more QML files, add them to the existing ecm_target_qml_sources() call. C++ files that use the keyword which we will see later in the tutorial can be added using target_sources().
The application needs to set its icon theme, QStyle, and QtQuick Controls style to Breeze in order to show up on Windows. To learn more about it, see .
If you want to get ahead, you can read more about how this main.cpp works in
If you want to see a few ways on how the C++ code can be improved, like using for translatable application metadata, be sure to check our .
This above follows the pattern <resource_prefix><import_URI><optional_QML_dir><file>. In this case:
If you are compiling your project on Windows after having set up , CMake should automatically detect the right compiler:
Next time you want to create the files and folders needed, you can use or to automatically generate a suitable project to start from. They are available from each major distribution's repositories. These applications will also generate files containing metadata and a .desktop file that contains information about how the application should be displayed in a linux application launcher.
Thanks to the magic of CMakeLists, you can also use IDEs such as KDevelop or to develop this application within a comfortable environment with minimal effort.
