Elias Naur
9b3429d6da
The layout package switched from interfaces to functions for composing layouts. The switch made sure that no garbage is generated for transient layouts such as Align, Inset, Stack, Flex. Unfortunately, that left the stateful widgets and layouts: as soon as their layout methods are embedded in a transient layout, a closure is generated that escapes to the heap. To avoid garbage for both transient as well as stateful widgets, replace the functional approach with explicit begin/end methods. A begin method generally starts an op block and returns the adjusted constraints. An end method takes computed dimensions, ends its op block and returns adjusted dimensions. Signed-off-by: Elias Naur <mail@eliasnaur.com>
Gio
Gio implements portable immediate mode GUI programs in Go. Gio programs run on all the major platforms: iOS/tvOS, Android, Linux (Wayland), macOS, Windows and browsers (Webassembly/WebGL).
Gio includes an efficient vector renderer based on the Pathfinder project (https://github.com/pcwalton/pathfinder). Text and other shapes are rendered using only their outlines without baking them into texture images, to support efficient animations, transformed drawing and pixel resolution independence.
Quickstart
Gio is designed to work with very few dependencies. It depends only on the platform libraries for window management, input and GPU drawing.
For Linux you need Wayland and the wayland, xkbcommon, GLES, EGL development packages. On Fedora 28 and newer, install the dependencies with the command
$ sudo dnf install wayland-devel libxkbcommon-devel mesa-libGLES-devel mesa-libEGL-devel
On Ubuntu 18.04 and newer, use
$ sudo apt install libwayland-dev libxkbcommon-dev libgles2-mesa-dev libegl1-mesa-dev
Note that Gio does not run with the NVIDIA proprietary driver.
Xcode is required for macOS, iOS, tvOS.
For Windows you need the ANGLE drivers for emulating OpenGL ES. You can build ANGLE yourself or use a prebuilt version.
With Go 1.12 or newer,
$ export GO111MODULE=on
$ go run gioui.org/apps/hello
should display a simple message in a window.
The command
$ go run gioui.org/apps/gophers
runs a simple (nonsense) demo that displays Go contributors fetched from GitHub.
If you run into quota issues, supply a
Github token
with the -token flag:
$ go run gioui.org/apps/gophers -token <github token>
Android
For Android you need the Android SDK with the NDK installed. Point the ANDROID_HOME to the SDK root directory.
To build a Gio program as an .aar package, use the gio tool. For example,
$ export ANDROID_HOME=...
$ go run gioui.org/cmd/gio -target android gioui.org/apps/gophers
produces gophers.aar, ready to use in an Android project. To run the demo on an Android device:
$ git clone https://git.sr.ht/~eliasnaur/gio
$ cd gio/apps/gophers/android
$ go run gioui.org/cmd/gio -target android ..
$ ./gradlew installDebug # gradlew.bat on Windows
The gio tool passes command line arguments to os.Args at runtime:
$ go run gioui.org/cmd/gio -target android .. -token <github token>
iOS/tvOS
To build a Gio program for iOS or tvOS you need a macOS machine with Xcode installed.
The gio tool can produce a framework ready to include in an Xcode project. For example,
$ go run gioui.org/cmd/gio -target ios gioui.org/apps/gophers
outputs Gophers.framework with the demo program built for iOS. For tvOS, use -target tvos:
$ go run gioui.org/cmd/gio -target tvos gioui.org/apps/gophers
Building for tvOS requires (the not yet released) Go 1.13.
To run the demo on an iOS device, use the sample Xcode project:
$ git clone https://git.sr.ht/~eliasnaur/gio
$ cd gio/apps
$ go run gioui.org/cmd/gio -target ios -o gophers/ios/gophers/Gophers.framework ./gophers
$ open gophers/ios/gophers.xcodeproj/
You need to provide a valid bundle identifier and set up code signing in Xcode to run the demo on a device. If you're using Go 1.12 or older, you also need to disable bitcode.
Webassembly/WebGL
To run a Gio program in a browser with WebAssembly and WebGL support, use the Go webassembly driver and add a
$ go get github.com/shurcooL/goexec
$ git clone https://git.sr.ht/~eliasnaur/gio
$ cd gio/apps/
$ GOOS=js GOARCH=wasm go build -o gophers/web/main.wasm ./gophers/
$ goexec 'http.ListenAndServe(":8080", http.FileServer(http.Dir("gophers/web")))'
and then open http://localhost:8080 in a browser.
Issues
File bugs and TODOs through the the issue tracker or send an email to ~eliasnaur/gio@todo.sr.ht. For general discussion, use the mailing list: ~eliasnaur/gio-dev@lists.sr.ht.
License
Dual-licensed under MIT or the UNLICENSE.
Contributing
Post discussion and patches to the mailing list. Send your message to ~eliasnaur/gio-dev@lists.sr.ht; no Sourcehut account is required and you can post without being subscribed.
Commit messages follow the Go project style:
the first line is prefixed with the package and a short summary. The rest of the message provides context
for the change and what it does. See
an example.
Add Fixes ~eliasnaur/gio#nnn or Updates ~eliasnaur/gio#nnn if the change fixes or updates an existing
issue.
The git send-email command is a convenient way to send patches to the mailing list. See
git-send-email.io for a thorough setup guide.
With git send-email configured, you can clone the project and set it up for submitting your changes:
$ git clone https://git.sr.ht/~eliasnaur/gio
$ cd gio
$ git config sendemail.to '~eliasnaur/gio-dev@lists.sr.ht'
$ git config sendemail.annotate yes
Configure your name and email address if you have not done so already:
$ git config --global user.email "you@gmail.com"
$ git config --global user.name "Your Name"
Contributors must agree to the developer certificate of origin,
to ensure their work is compatible with the MIT and the UNLICENSE. Sign your commits with Signed-off-by
statements to show your agreement. The git commit --signoff (or -s) command signs a commit with
your name and email address.
Whenever you want to submit your work for review, use git send-email with the base revision of your
changes. For example, to submit the most recent commit use
$ git send-email HEAD^