Added basic control showing to the Windows backend.

redo/controls_windows.go

@@ -19,7 +19,8 @@ func newWidget(class *uint16, style uintptr, extstyle uintptr) *widgetbase {
 		class, emptystr,
 		style | c_WS_CHILD | c_WS_VISIBLE,
 		c_CW_USEDEFAULT, c_CW_USEDEFAULT,
-		c_CW_USEDEFAULT, c_CW_USEDEFAULT,
+//		c_CW_USEDEFAULT, c_CW_USEDEFAULT,
+100,100,
 		// the following has the consequence of making the control message-only at first
 		// this shouldn't cause any problems... hopefully not
 		// but see the msgwndproc() for caveat info

redo/window_windows.go

@@ -12,6 +12,8 @@ type window struct {
 	hwnd		uintptr
 	shownbefore	bool
 
+	child			Control
+
 	closing		*event
 }
 
@@ -65,8 +67,12 @@ func (w *window) SetControl(control Control) *Request {
 	c := make(chan interface{})
 	return &Request{
 		op:		func() {
-			// TODO unparent
-			// TODO reparent
+			if w.child != nil {		// unparent existing control
+				w.child.unparent()
+			}
+			control.unparent()
+			control.parent(w)
+			w.child = control
 			c <- struct{}{}
 		},
 		resp:		c,