Reverted everything back to the old API.

1 files changed, 22 insertions, 4 deletions

diff --git a/sysdata.go b/sysdata.go
index 9144517..4a95591 100644
--- a/sysdata.go
+++ b/sysdata.go
@@ -2,16 +2,21 @@
 
 package ui
 
+const eventbufsiz = 100 // suggested by skelterjohn
+
+// newEvent returns a new channel suitable for listening for events.
+func newEvent() chan struct{} {
+	return make(chan struct{}, eventbufsiz)
+}
+
 // The sysData type contains all system data. It provides the system-specific underlying implementation. It is guaranteed to have the following by embedding:
 type cSysData struct {
 	ctype     int
+	event     chan struct{}
 	allocate    func(x int, y int, width int, height int, d *sysSizeData) []*allocation
 	spaced	bool
 	alternate bool        // editable for Combobox, multi-select for listbox, password for lineedit
-	handler   AreaHandler // for Areas; TODO rename to areahandler
-	winhandler	WindowHandler	// for Windows
-	close	func(*bool)	// provided by each Window
-	event	func()		// provided by each control
+	handler   AreaHandler // for Areas
 }
 
 // this interface is used to make sure all sysDatas are synced
@@ -39,6 +44,19 @@ var _xSysData interface {
 	setChecked(bool)
 } = &sysData{} // this line will error if there's an inconsistency
 
+// signal sends the event signal. This raise is done asynchronously to avoid deadlocking the UI task.
+// Thanks skelterjohn for this techinque: if we can't queue any more events, drop them
+func (s *cSysData) signal() {
+	if s.event != nil {
+		go func() {
+			select {
+			case s.event <- struct{}{}:
+			default:
+			}
+		}()
+	}
+}
+
 const (
 	c_window = iota
 	c_button