diff --git a/init.go b/init.go index 0474612..d8203e2 100644 --- a/init.go +++ b/init.go @@ -2,21 +2,39 @@ package ui -// Go sets up the UI environment and runs main in a goroutine. -// If initialization fails, Go returns an error and main is not called. -// Otherwise, Go does not return to its caller until main does, at which point it returns nil. -// After it returns, you cannot call future ui functions/methods meaningfully. +import ( + "runtime" +) + +// Go sets up the UI environment and pulses Ready. +// If initialization fails, Go returns an error and Ready is not pulsed. +// Otherwise, Go does not return to its caller until Stop is pulsed, at which point Go() will return nil. +// After Go() returns, you cannot call future ui functions/methods meaningfully. +// Pulsing Stop will cause Go() to return immediately; the programmer is responsible for cleaning up (for instance, hiding open Windows) beforehand. // -// It is not safe to call ui.Go() in a goroutine. It must be called directly from main(). +// It is not safe to call ui.Go() in a goroutine. It must be called directly from main(). This means if your code calls other code-modal servers (such as http.ListenAndServe()), they must be run from goroutines. (This is due to limitations in various OSs, such as Mac OS X.) // -// This model is undesirable, but Cocoa limitations require it. -// -// Go does not process the command line for flags (that is, it does not call flag.Parse()), nor does package ui add any of the underlying toolkit's supported command-line flags. +// Go() does not process the command line for flags (that is, it does not call flag.Parse()), nor does package ui add any of the underlying toolkit's supported command-line flags. // If you must, and if the toolkit also has environment variable equivalents to these flags (for instance, GTK+), use those instead. -func Go(main func()) error { - return ui(main) +func Go() error { + runtime.LockOSThread() + if err := uiinit(main); err != nil { + return err + } + Ready <- struct{}{} + close(Ready) + ui() } +// Ready is pulsed when Go() is ready to begin accepting requests to the safe methods. +// Go() will wait for something to receive on Ready, then Ready will be closed. +var Ready = make(chan struct{}) + +// Stop should be pulsed when you are ready for Go() to return. +// Pulsing Stop will cause Go() to return immediately; the programmer is responsible for cleaning up (for instance, hiding open Windows) beforehand. +// Do not pulse Stop more than once. +var Stop = make(chan struct{}) + // This function is a simple helper functionn that basically pushes the effect of a function call for later. This allows the selected safe Window methods to be safe. // It's also currently used by the various dialog box functions on Windows to allow them to return instantly, rather than wait for the dialog box to finish (which both GTK+ and Mac OS X let you do). I consider this a race condition bug. TODO (also TODO document the /intended/ behavior) func touitask(f func()) {