Added a flag to AreaHandler.Key()/Mouse() to indicate that a repaint is needed after that event has been handled. (Having Repaint() as a method deadlocked for the same reason resizing deadlocked before.)

area.go

@@ -52,13 +52,15 @@ type AreaHandler interface {
 	// Mouse is called when the Area receives a mouse event.
 	// You are allowed to do nothing in this handler (to ignore mouse events).
 	// See MouseEvent for details.
-	Mouse(e MouseEvent)
+	// If repaint is true, the Area is marked as needing to be redrawn.
+	Mouse(e MouseEvent) (repaint bool)
 
 	// Key is called when the Area receives a keyboard event.
-	// You are allowed to do nothing except return false in this handler (to ignore keyboard events).
+	// You are allowed to do nothing except return false for handled in this handler (to ignore keyboard events).
-	// Do not do nothing but return true; this may have unintended consequences.
+	// Do not do nothing but return true for handled; this may have unintended consequences.
 	// See KeyEvent for details.
-	Key(e KeyEvent) bool
+	// If repaint is true, the Area is marked as needing to be redrawn.
+	Key(e KeyEvent) (handled bool, repaint bool)
 }
 
 // MouseEvent contains all the information for a mous event sent by Area.Mouse.
@@ -116,16 +118,17 @@ func (e MouseEvent) HeldBits() (h uintptr) {
 // 
 // When you are finished processing the incoming event,
 // return whether or not you did something in response
-// to the given keystroke from your Key() implementation.
+// to the given keystroke as the handled return of your
-// If you send false, you indicate that you did not handle
+// AreaHandler's Key() implementation. If you send false,
-// the keypress, and that the system should handle it instead.
+// you indicate that you did not handle the keypress, and that
-// (Some systems will stop processing the keyboard event at all
+// the system should handle it instead. (Some systems will stop
-// if you return true unconditionally, which may result in unwanted
+// processing the keyboard event at all if you return true
-// behavior like global task-switching keystrokes not being processed.)
+// unconditionally, which may result in unwanted behavior like
+// global task-switching keystrokes not being processed.)
 // 
 // If a key is pressed that is not supported by ASCII, ExtKey,
 // or Modifiers, no KeyEvent will be produced, and package
-// ui will act as if false was returned.
+// ui will act as if false was returned for handled.
 type KeyEvent struct {
 	// ASCII is a byte representing the character pressed.
 	// Despite my best efforts, this cannot be trivialized

area_unix.go

@@ -103,7 +103,7 @@ func makeModifiers(state C.guint, m Modifiers) Modifiers {
 }
 
 // shared code for finishing up and sending a mouse event
-func finishMouseEvent(data C.gpointer, me MouseEvent, mb uint, x C.gdouble, y C.gdouble, state C.guint, gdkwindow *C.GdkWindow) {
+func finishMouseEvent(widget *C.GtkWidget, data C.gpointer, me MouseEvent, mb uint, x C.gdouble, y C.gdouble, state C.guint, gdkwindow *C.GdkWindow) {
 	s := (*sysData)(unsafe.Pointer(data))
 	state = translateModifiers(state, gdkwindow)
 	me.Modifiers = makeModifiers(state, 0)
@@ -125,7 +125,10 @@ func finishMouseEvent(data C.gpointer, me MouseEvent, mb uint, x C.gdouble, y C.
 		me.Held = append(me.Held, 5)
 	}
 	me.Pos = image.Pt(int(x), int(y))
-	s.handler.Mouse(me)
+	repaint := s.handler.Mouse(me)
+	if repaint {
+		C.gtk_widget_queue_draw(widget)
+	}
 }
 
 //export our_area_button_press_event_callback
@@ -143,7 +146,7 @@ func our_area_button_press_event_callback(widget *C.GtkWidget, event *C.GdkEvent
 	default:		// ignore triple-clicks and beyond; we don't handle those
 		return C.FALSE		// TODO really false?
 	}
-	finishMouseEvent(data, me, me.Down, e.x, e.y, e.state, e.window)
+	finishMouseEvent(widget, data, me, me.Down, e.x, e.y, e.state, e.window)
 	return C.FALSE			// TODO really false?
 }
 
@@ -156,7 +159,7 @@ func our_area_button_release_event_callback(widget *C.GtkWidget, event *C.GdkEve
 		// GDK button ID == our button ID
 		Up:		uint(e.button),
 	}
-	finishMouseEvent(data, me, me.Up, e.x, e.y, e.state, e.window)
+	finishMouseEvent(widget, data, me, me.Up, e.x, e.y, e.state, e.window)
 	return C.FALSE			// TODO really false?
 }
 
@@ -166,14 +169,14 @@ var area_button_release_event_callback = C.GCallback(C.our_area_button_release_e
 func our_area_motion_notify_event_callback(widget *C.GtkWidget, event *C.GdkEvent, data C.gpointer) C.gboolean {
 	e := (*C.GdkEventMotion)(unsafe.Pointer(event))
 	me := MouseEvent{}
-	finishMouseEvent(data, me, 0, e.x, e.y, e.state, e.window)
+	finishMouseEvent(widget, data, me, 0, e.x, e.y, e.state, e.window)
 	return C.FALSE			// TODO really false?
 }
 
 var area_motion_notify_event_callback = C.GCallback(C.our_area_motion_notify_event_callback)
 
 // shared code for doing a key event
-func doKeyEvent(event *C.GdkEvent, data C.gpointer, up bool) bool {
+func doKeyEvent(widget *C.GtkWidget, event *C.GdkEvent, data C.gpointer, up bool) bool {
 	var ke KeyEvent
 
 	e := (*C.GdkEventKey)(unsafe.Pointer(event))
@@ -202,7 +205,11 @@ fmt.Println("$$", up, e.hardware_keycode)
 	state := translateModifiers(e.state, e.window)
 	ke.Modifiers = makeModifiers(state, ke.Modifiers)
 	ke.Up = up
-	return s.handler.Key(ke)
+	handled, repaint := s.handler.Key(ke)
+	if repaint {
+		C.gtk_widget_queue_draw(widget)
+	}
+	return handled
 }
 
 //export our_area_key_press_event_callback
@@ -218,7 +225,7 @@ func our_area_key_press_event_callback(widget *C.GtkWidget, event *C.GdkEvent, d
 	fmt.Printf("%d/GDK_KEY_a:\n", C.GDK_KEY_a)
 	pk(C.GDK_KEY_a, e.window)
 */
-	ret := doKeyEvent(event, data, false)
+	ret := doKeyEvent(widget, event, data, false)
 	_ = ret
 	return C.FALSE			// TODO really false? should probably return !ret (since true indicates stop processing)
 }
@@ -227,7 +234,7 @@ var area_key_press_event_callback = C.GCallback(C.our_area_key_press_event_callb
 
 //export our_area_key_release_event_callback
 func our_area_key_release_event_callback(widget *C.GtkWidget, event *C.GdkEvent, data C.gpointer) C.gboolean {
-	ret := doKeyEvent(event, data, true)
+	ret := doKeyEvent(widget, event, data, true)
 	_ = ret
 	return C.FALSE			// TODO really false? should probably return !ret (since true indicates stop processing)
 }

area_windows.go

@@ -329,6 +329,7 @@ func getModifiers() (m Modifiers) {
 	return m
 }
 
+// TODO mark repaint
 func areaMouseEvent(s *sysData, button uint, up bool, count uint, wparam _WPARAM, lparam _LPARAM) {
 	var me MouseEvent
 
@@ -403,6 +404,7 @@ func areaWndProc(s *sysData) func(hwnd _HWND, uMsg uint32, wParam _WPARAM, lPara
 			areaMouseEvent(s, 3, true, 0, wParam, lParam)
 			return 0
 		// TODO XBUTTONs?
+		// TODO mark repaint in key events
 		default:
 			r1, _, _ := defWindowProc.Call(
 				uintptr(hwnd),

test/kbtest.go

@@ -34,7 +34,9 @@ func (a *keyboardArea) Paint(cliprect image.Rectangle) *image.NRGBA {
 	return a.kbd.SubImage(cliprect).(*image.NRGBA)
 }
 
-func (a *keyboardArea) Mouse(MouseEvent) {}
+func (a *keyboardArea) Mouse(MouseEvent) (repaint bool) {
+	return false
+}
 
 func markkey(dest *image.NRGBA, keypt image.Point, m Modifiers) {
 	xr := keyrect(m).Add(keypt)
@@ -42,7 +44,7 @@ func markkey(dest *image.NRGBA, keypt image.Point, m Modifiers) {
 	draw.Draw(dest, xr, xi, image.ZP, draw.Over)
 }
 
-func (a *keyboardArea) Key(e KeyEvent) bool {
+func (a *keyboardArea) Key(e KeyEvent) (handled bool, repaint bool) {
 	a.lock.Lock()
 	defer a.lock.Unlock()
 
@@ -68,9 +70,9 @@ func (a *keyboardArea) Key(e KeyEvent) bool {
 //			markkey(a.kbd, modpoints[Super], m &^ Super)
 //		}
 	default:
-		return false
+		return false, false
 	}
-	return true
+	return true, true
 }
 
 var doKeyboard = flag.Bool("kb", false, "run keyboard test")

test/main.go

@@ -131,13 +131,14 @@ func (a *areaHandler) Paint(rect image.Rectangle) *image.NRGBA {
 */
 	return a.img.SubImage(rect).(*image.NRGBA)
 }
-func (a *areaHandler) Mouse(e MouseEvent) {
+func (a *areaHandler) Mouse(e MouseEvent) bool {
-	fmt.Printf("%#v\n", e)
-}
-func (a *areaHandler) Key(e KeyEvent) bool {
 	fmt.Printf("%#v\n", e)
 	return false
 }
+func (a *areaHandler) Key(e KeyEvent) (bool, bool) {
+	fmt.Printf("%#v\n", e)
+	return false, false
+}
 
 var doArea = flag.Bool("area", false, "run area test instead (overrides -kb)")
 func areaTest() {