Awesome

SwiftGtkListBoxDNDDemo

A simple demo in Swift of how to do drag-and-drop in gtk+ lists.

This is a demo, re-implemented in Swift, that follows the C version of Drag-and-drop in lists on the Gtk+ Development Blog. Be sure to check out the blog post, as it gives vital information on how drag-and-drop works (and can be implemented for lists) in GTK+.

Building

Make sure you have all the prerequisites installed (see below). After that, you can simply clone this repository and build the command line executable (be patient, this will download all the required dependencies and take a while to compile) using

git clone https://github.com/rhx/SwiftGtkListBoxDNDDemo.git
cd SwiftGtkListBoxDNDDemo
./run-gir2swift.sh
swift build

You can run the program using

swift run

A simple, empty 'Hello World' window should appear. To exit the program, click the close button or press Control-C in the Terminal window.

macOS

Please note that on macOS, due to a bug currently in the Swift Package Manager, you need to pass in the build flags manually, i.e. instead of swift build and swift run you can run

swift build `./run-gir2swift.sh flags -noUpdate`
swift run   `./run-gir2swift.sh flags -noUpdate`

Under macOS, you can also create an Application bundle that you can copy to the /Applications folder by using

./app-bundle.sh

Xcode

On macOS, you can build the project using Xcode instead. To do this, you need to create an Xcode project first, then open the project in the Xcode IDE:

./xcodegen.sh
open HelloGtk.xcodeproj

After that, select the executable target (not the Bundle/Framework target with the same name as the executable) and use the (usual) Build and Run buttons to build/run your project.

What is new?

Version 12 of gir2swift pulls in PR#10, addressing several issues:

• Improvements to the Build experience and LSP rhx/SwiftGtk#34
• Fix issues with LLDB rhx/SwiftGtk#39
• Controversial: Implicitly marks all declarations named "priv" as if they had attribute private=1
• Prevents all "Private" records from generating unless generated in their instance record
  • -a option generates all records
• Introduces CI
• For Class metadata types no longer generates class wrappers. Ref structs now contain static method which returnes the GType of the class and instance of the Class metatype wrapped in the Ref struct.
• Adds final class GWeak<T> where T could be any Ref struct of a type which supports ARC. This class is a property wrapper which contains weak reference to any instance of T. This is especially beneficial for capture lists.
• Adds support for weak observation.
• Constructors and factories of GObjectInitiallyUnowned classes now consume floating reference upon initialisation as advised by the GObject documentation

Partially implemented:

• Typed signal generation. Issues shown in rhx/SwiftGtk#35 hat remain to be addressed are listed here: mikolasstuchlik/gir2swift#2.

Other notable changes

Version 11 introduces a new type system into gir2swift, to ensure it has a representation of the underlying types. This is necessary for Swift 5.3 onwards, which requires more stringent casts. As a consequence, accessors can accept and return idiomatic Swift rather than underlying types or pointers. This means that a lot of the changes will be source-breaking for code that was compiled against libraries built with earlier versions of gir2swift.

• Requires Swift 5.2 or later
• Wrapper code is now @inlinable to enable the compiler to optimise away most of the wrappers
• Parameters and return types use more idiomatic Swift (e.g. Ref wrappers instead of pointers, Int instead of gint, etc.)
• Functions that take or return records now are templated instead of using the type-erased Protocol
• ErrorType has been renamed GLibError to ensure it neither clashes with Swift.Error nor the GLib.ErrorType scanner enum
• Parameters or return types for records/classes now use the corresponding, lightweight Swift Ref wrapper instead of the underlying pointer

Prerequisites

Swift

Building should work with at least Swift 5.2 (Swift 5.3+ should work). You can download Swift from https://swift.org/download/ -- if you are using macOS, make sure you have the command line tools installed as well (install them using xcode-select --install). Test that your compiler works using swift --version, which should give you something like

$ swift --version
Apple Swift version 5.3.2 (swiftlang-1200.0.45 clang-1200.0.32.28)
Target: x86_64-apple-darwin20.3.0

on macOS, or on Linux you should get something like:

$ swift --version
Swift version 5.3.2 (swift-5.3.2-RELEASE)
Target: x86_64-unknown-linux-gnu

Gtk 3.18 or higher

The Swift wrappers have been tested with glib-2.46, 2.48, 2.52, 2.56, 2.58, 2.60, 2.62, 2.64 and 2.66, and gdk/gtk 3.18, 3.20, 3.22, and 3.24. They should work with higher versions, but YMMV. Also make sure you have gobject-introspection and its .gir files installed.

Linux

Ubuntu

On Ubuntu 18.04 and 16.04 you can use the gtk that comes with the distribution. Just install with the apt package manager:

sudo apt update
sudo apt install libgtk-3-dev gir1.2-gtksource-3.0 gobject-introspection libgirepository1.0-dev libxml2-dev

If you prefer a newer version of gtk, you can also install it from the GNOME 3 Staging PPA (see https://launchpad.net/~gnome3-team/+archive/ubuntu/gnome3-staging), but be aware that this can be a bit dangerous (as this removes packages that can be vital, particularly if you use a GNOME-based desktop), so only do this if you know what you are doing:

sudo add-apt-repository ppa:gnome3-team/gnome3-staging
sudo apt update
sudo apt dist-upgrade
sudo apt install libgtk-3-dev gir1.2-gtksource-3.0 gobject-introspection libgirepository1.0-dev libxml2-dev

Fedora

On Fedora 29, you can use the gtk that comes with the distribution. Just install with the dnf package manager:

sudo dnf install gtk3-devel pango-devel cairo-devel cairo-gobject-devel glib2-devel gobject-introspection-devel libxml2-devel

macOS

On macOS, you can install gtk using HomeBrew (for setup instructions, see http://brew.sh). Once you have a running HomeBrew installation, you can use it to install a native version of gtk:

brew update
brew install gtk+3 glib glib-networking gobject-introspection pkg-config

Troubleshooting

Here are some common errors you might encounter and how to fix them.

Old Swift toolchain or Xcode

If you get an error such as

$ ./build.sh 
error: unable to invoke subcommand: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift-package (No such file or directory)

this probably means that your Swift toolchain is too old. Make sure the latest toolchain is the one that is found when you run the Swift compiler (see above).

If you get an older version, make sure that the right version of the swift compiler is found first in your PATH. On macOS, use xcode-select to select and install the latest version, e.g.:

sudo xcode-select -s /Applications/Xcode.app
xcode-select --install

Known Issues

• When building, a lot of warnings appear. This is largely an issue with automatic RawRepresentable conformance in the Swift Standard library. As a workaround, you can turn this off by passing the -Xswiftc -suppress-warnings parameter when building.

• The current build system does not support directory paths with spaces (e.g. the My Drive directory used by Google Drive File Stream).

• BUILD_DIR is not supported in the current build system.

As a workaround, you can use the old build scripts, e.g. ./build.sh (instead of run-gir2swift.sh and swift build) to build a package.