1 files changed, 54 insertions, 0 deletions
diff --git a/uitask.go b/uitask.go
new file mode 100644
index 0000000..72f24ef
--- /dev/null
+++ b/uitask.go
@@ -0,0 +1,54 @@
+// 11 february 2014
+
+package ui
+
+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(). 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.)
+//
+// 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() error {
+	runtime.LockOSThread()
+	if err := uiinit(); err != nil {
+		return err
+	}
+	Ready <- struct{}{}
+	close(Ready)
+	ui()
+	return nil
+}
+
+// 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.
+// TODO make sure this acts sanely if called from uitask itself
+func touitask(f func()) {
+	done := make(chan struct{})
+	defer close(done)
+	go func() {		// to avoid locking uitask itself
+		done2 := make(chan struct{})		// make the chain uitask <- f <- uitask to avoid deadlocks
+		defer close(done2)
+		uitask <- func() {
+			f()
+			done2 <- struct{}{}
+		}
+		done <- <-done2
+	}()
+	<-done
+}