ruby-qml Gem Version
ruby-qml is a QML / Qt Quick wrapper for Ruby. It provides bindings between QML and Ruby and enables you to use Qt Quick-based GUI from Ruby.
Dependency Status Build Status Coverage Status Inline docs
- Develop desktop GUI applications only with Ruby and QML / JavaScript
- Easily combine codes written in C++ and Qt with your Ruby code
- Ruby 2.1 or later
- OS X or Linux
- Qt 5.4 or later
To install ruby-qml on OS X with Homebrew, run the following commands:
$ brew install qt5
$ gem install qml -- --with-qmake=$(brew --prefix qt5)/bin/qmake
Both libffi and Qt5 are keg-only in Homebrew, so you must specify their paths explicitly (or force linking).
If you use official Qt installation, for example:
$ gem install qml -- --with-qmake=$HOME/Qt/5.4/clang_64/bin/qmake
The Qt installation path ($HOME/Qt/5.4/clang_64 in this example) depends on your Qt installation configuration and Qt version.
$ gem install qml
$ sudo apt install ruby ruby-dev build-essentials qt5-default qtdeclarative5-dev qtbase5-private-dev qml-module-qtquick2 qml-module-qtquick-controls
$ sudo gem install qml
Using Ubuntu as the linux distro, proceed as above and use either WSL2 or an XServer (e.g. vcxsrv) to show the UI on Windows.
--with-qmake=[dir]- Qt qmake executable path (optional).
Add this line to your Gemfile:
gem 'qml'
And then execute:
$ bundle install
To pass build options, use bundle config.
For example:
$ bundle config build.qml --with-qmake=$(brew --prefix qt5)/bin/qmake
The configuration will be saved in ~/.bundle/config.
The following code loads a QML file and shows an application window titled "Hello, world!".
require 'qml' QML.run do |app| app.load_path Pathname(__FILE__) + '../main.qml' end
// main.qml import QtQuick 2.2 import QtQuick.Controls 1.1 ApplicationWindow { visible: true width: 200 height: 100 title: "Hello, world!" }
To make your class available to QML, include QML::Access and call register_to_qml.
By including QML::Access, you can also define properties and signals in Ruby classes like in QML.
Properties are used to bind data between QML and Ruby. Signals are used to provide the observer pattern-like notification from Ruby to QML.
# Ruby class FizzBuzz include QML::Access register_to_qml under: "Example", version: "1.0" property(:input) { '0' } property(:result) { '' } signal :inputWasFizzBuzz, [] on_changed :input do i = input.to_i self.result = case when i % 15 == 0 inputWasFizzBuzz.emit "FizzBuzz" when i % 3 == 0 "Fizz" when i % 5 == 0 "Buzz" else i.to_s end end def quit puts "quitting..." QML.application.quit end end
// QML - main.qml import QtQuick 2.2 import QtQuick.Controls 1.1 import QtQuick.Layouts 1.1 import Example 1.0 ApplicationWindow { visible: true width: 200 height: 200 title: "FizzBuzz" ColumnLayout { anchors.fill: parent anchors.margins: 10 TextField { placeholderText: "Input" text: "0" id: textField } Text { id: text text: fizzBuzz.result } Button { text: 'Quit' onClicked: fizzBuzz.quit() } Text { id: lastFizzBuzz } } FizzBuzz { id: fizzBuzz input: textField.text onInputWasFizzBuzz: lastFizzBuzz.text = "Last FizzBuzz: " + textField.text } }
You can omit arguments of register_to_qml if they are obvious:
module Example VERSION = '1.0.0' class FizzBuzz include QML::Access register_to_qml ... end end
To bind list data between QML ListView and Ruby, you can use ListModels.
-
QML::ListModel- the base class for ruby-qml list models. -
QML::ArrayModel- provides a simple list model implementation using Array. -
QML::QueryModel- for databases (like ActiveRecord, Sequel or something)
This example uses ArrayModel to provide list data for a QML ListView.
When the content of the ArrayModel is changed, the list view is also automatically updated.
# Ruby class TodoController include QML::Access register_to_qml under: "Example", version: "1.0" property(:model) { QML::ArrayModel.new(:title, :description, :due_date) } def add(title, description, due_date) # Items of list models must be "Hash-like" (have #[] method to get columns) item = { title: title, description: description, due_date: due_date } model << item end end
// QML ListView { model: todo.model delegate: Text { text: "Title: " + title + ", Description: " + description + ", Due date: " + due_date } } TodoController { id: todo }
In QML, all UI-related operations are done synchronously in the event loop.
To set result of asynchronous operations to the UI, use QML.next_tick.
# Ruby class HeavyTaskController include QML::Access register_to_qml under: "Example", version: "1.0" property(:result) { '' } def set_result(result) self.result = result end def start_heavy_task Thread.new do QML.next_tick do set_result do_heavy_task() end end end end
// QML Text { text: controller.result } Button { text: "Start!!" onClicked: controller.start_heavy_task() } HeavyTaskController { id: controller }
| Ruby | QML/JavaScript |
|---|---|
| nil | null |
| true/false | boolean |
| Numeric | number |
| String/Symbol | string |
| Array | Array |
| Hash | plain Object |
| Proc | Function |
| Time | Date |
| QML::Access | Object(QObject derived) |
| QML::ListModel | Object(QAbstractListModel) |
You can customize this by implementing #to_qml method.
| QML/JavaScript | Ruby |
|---|---|
| null/undefined | nil |
| boolean | true/false |
| number | Float |
| string | String |
| Array | QML::JSArray |
| Function | QML::JSFunction |
| Object | QML::JSObject |
| Object wrapping QML::Access | QML::JSWrapper |
You can convert Objects further through QML::JSObject methods.
QML::JSObject is the wrapper class for JavaScript objects.
obj = QML.engine.evaluate <<-JS ({ value: 1, add: function(d) { this.value += d; } }) JS # Getter obj.value #=> 1 # Setter obj.value = 2 obj.vaue #=> 2 # Call method if the property is a function obj.add(10) obj.value #=> 11 # Subscription obj[:value] #=> 11 obj[:add] #=> #<QML::JSFunction:...>
PluginLoader loads Qt C++ plugins.
It enables you to use your Qt C++ codes from Ruby easily.
// C++ - plugin example class MyPlugin : public QObject { Q_OBJECT Q_PLUGIN_METADATA(IID "org.myplugin.MyPlugin") signals: void added(int value); public slots: int add(int x, int y) { int result = x + y; emit added(result); return result; } };
# Ruby # The instance will be a `QML::JSObject` which represents the plugin Qt object plugin = QML::PluginLoader.new(directory, "myplugin").instance # Connect to signal (see http://doc.qt.io/qt-5/qtqml-syntax-signals.html#connecting-signals-to-methods-and-signals) plugin[:added].connect do |value| puts "added value: #{value}" end plugin.add(1, 2) #=> 3
You can use EventMachine with ruby-qml. It is more powerful than the default ruby-qml event loop.
Instead of using QML.run, start an EventMachine event loop by EM.run and
process QML events periodically by QML::Application#process_events.
require 'qml' require 'eventmachine' EM.run do QML.init EM.add_periodic_timer(0.01) { QML.application.process_events } QML.application.load_path(Pathname.pwd + 'main.qml') end
You can also use em-synchrony to write callback-free asynchronous operation for ruby-qml.
require 'qml' require 'eventmachine' require 'em-synchrony' require 'em-http-request' class Controller include QML::Access property(:result) { '' } def get EM.synchrony do content = EM::Synchrony.sync EM::HttpRequest.new('http://www.example.com/').get self.result = content.response end end def quit EM.stop end register_to_qml under: 'Example', version: '0.1' end EM.run do QML.init EM.add_periodic_timer(0.01) { QML.application.process_events } QML.application.load_path(Pathname.pwd + 'main.qml') end
$ git submodule init
$ git submodule update
$ bundle install
Before running ruby-qml in development, the native extension of ruby-qml needs to have been built. To build it, run the following commands:
$ cd ext/qml
$ bundle exec ruby extconf.rb --with-qmake=/path/to/qmake
$ make -j4
Tests for ruby-qml is written in RSpec. To run tests, do:
$ bundle exec rspec
$ bundle exec ruby examples/fizzbuzz/fizzbuzz.rb
- Fork it ( http://github.com/seanchas116/ruby-qml/fork )
- Create your feature branch (
git checkout -b my-new-feature) - Commit your changes (
git commit -am 'Add some feature') - Write some tests
- Push to the branch (
git push origin my-new-feature) - Create new Pull Request