forked from joejulian/gio
Elias Naur
37717d0df9
The goroutine started by Window.run runs concurrently with the user goroutine receiving from Window.Events, leading to races such as #543. This change replaces the Window.run goroutine and the Window.Events channel with an iterator API driven by the user goroutine directly. Fixes: https://todo.sr.ht/~eliasnaur/gio/543 Signed-off-by: Elias Naur <mail@eliasnaur.com>
74 lines
1.9 KiB
Go
74 lines
1.9 KiB
Go
// SPDX-License-Identifier: Unlicense OR MIT
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/*
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Package app provides a platform-independent interface to operating system
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functionality for running graphical user interfaces.
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See https://gioui.org for instructions to set up and run Gio programs.
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# Windows
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Create a new Window by calling NewWindow. On mobile platforms or when Gio
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is embedded in another project, NewWindow merely connects with a previously
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created window.
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A Window is run by calling NextEvent in a loop. The most important event is
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FrameEvent that prompts an update of the window contents.
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For example:
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import "gioui.org/unit"
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w := app.NewWindow()
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for {
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e := w.NextEvent()
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if e, ok := e.(system.FrameEvent); ok {
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ops.Reset()
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// Add operations to ops.
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...
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// Completely replace the window contents and state.
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e.Frame(ops)
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}
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}
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A program must keep receiving events from the event channel until
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DestroyEvent is received.
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# Main
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The Main function must be called from a program's main function, to hand over
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control of the main thread to operating systems that need it.
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Because Main is also blocking on some platforms, the event loop of a Window must run in a goroutine.
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For example, to display a blank but otherwise functional window:
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package main
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import "gioui.org/app"
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func main() {
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go func() {
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w := app.NewWindow()
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for {
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w.NextEvent()
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}
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}()
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app.Main()
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}
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# Event queue
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A FrameEvent's Queue method returns an event.Queue implementation that distributes
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incoming events to the event handlers declared in the last frame.
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See the gioui.org/io/event package for more information about event handlers.
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# Permissions
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The packages under gioui.org/app/permission should be imported
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by a Gio program or by one of its dependencies to indicate that specific
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operating-system permissions are required. Please see documentation for
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package gioui.org/app/permission for more information.
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*/
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package app
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