README
¶
gtk4
Drive GTK4 from pure Go with CGO_ENABLED=0 — windows, the common
controls, GObject signals and the GLib main loop — over
ebitengine/purego.
It is the Linux sibling of go-macos/objc:
the shared native-toolkit bridge a go-widgets
host backend embeds real controls through, so a pixel-drawn app can inlay a real
GtkEntry, GtkButton or secure field over its own rendering.
ok, err := gtk4.Init()
// win := gtk4.WindowNew(); win.SetTitle("…"); win.SetDefaultSize(360, 200)
// fixed := gtk4.FixedNew() // the overlay container
// e := gtk4.EntryNew(); e.SetVisibility(false) // a password field
// b := gtk4.ButtonNewWithLabel("OK")
// b.Connect("clicked", func() { … }) // a GObject signal, as a Go closure
// fixed.Put(e, 10, 10); fixed.Put(b, 10, 44); win.SetChild(fixed); win.Present()
No cgo
libgtk-4, libgobject-2.0 and libglib-2.0 are dlopen'd by soname and
every entry point is resolved with purego.RegisterLibFunc. A GObject signal
reaches Go through a purego.NewCallback, retained for the process life (GTK
holds the C pointer). The package links with no cgo and cross-compiles like any
other Go code.
What it binds
Init · WindowNew (+ SetTitle/SetDefaultSize/SetChild/Present) ·
FixedNew (+ Put/Move — absolute overlay positioning) · ButtonNewWithLabel
(+ SetLabel) · EntryNew (+ SetVisibility for a secure field) ·
CheckButtonNewWithLabel (+ Active/SetActive; grouped check buttons are GTK
radios) · LabelNew · Text/SetText (GtkEditable) · SetSizeRequest ·
SetVisible · Unparent · Connect (signals) · MainLoop (Run/Quit) ·
IdleAdd (marshal onto the GTK thread).
Platform
Linux only — this is the GTK path; a go-widgets host uses AppKit/Win32 on
macOS/Windows. Off Linux the package still compiles (a consumer cross-compiles
without a build tag) and every constructor's Init returns
ErrUnsupported, so
nothing is a build-time surprise. It needs only the runtime libgtk-4
(libgtk-4-1 on Debian/Ubuntu) — no -dev package.
Testing
CI builds it on every platform and runs a live test against real GTK4 under a
headless X server (Xvfb) — creating a window, entry, secure field, button and
check button, round-tripping their values, and proving a changed signal reaches
Go through the main loop.
License
BSD-3-Clause. See LICENSE.
Documentation
¶
Index ¶
- Variables
- func IdleAdd(func())
- func Init() (bool, error)
- type MainLoop
- type Widget
- func (w Widget) Active() bool
- func (w Widget) Connect(string, func()) uint64
- func (f Widget) Move(Widget, float64, float64)
- func (w Widget) Present()
- func (f Widget) Put(Widget, float64, float64)
- func (w Widget) SetActive(bool)
- func (w Widget) SetChild(Widget)
- func (w Widget) SetDefaultSize(int, int)
- func (w Widget) SetLabel(string)
- func (w Widget) SetSizeRequest(int, int)
- func (w Widget) SetText(string)
- func (w Widget) SetTitle(string)
- func (w Widget) SetVisibility(bool)
- func (w Widget) SetVisible(bool)
- func (w Widget) Text() string
- func (w Widget) Unparent()
Constants ¶
This section is empty.
Variables ¶
var ErrUnsupported = errors.New("gtk4: only available on Linux")
ErrUnsupported is returned by Init on any platform without GTK4 (everything but Linux). It is defined on every platform so a portable consumer can test for it with errors.Is.
Functions ¶
Types ¶
type MainLoop ¶
type MainLoop uintptr
MainLoop is a GLib main loop. Off Linux it does nothing.
func MainLoopNew ¶
func MainLoopNew() MainLoop
type Widget ¶
type Widget uintptr
Widget is a GTK widget. Off Linux no real one is ever created.
func ButtonNewWithLabel ¶
func CheckButtonNewWithLabel ¶
func WindowNew ¶
func WindowNew() Widget
The constructors return the null widget off Linux; the methods are no-ops or zero, so consumer code that names them still compiles.
Source Files