Implemented the new MsgBox() transience on Windows.

dialog_windows.go

@@ -13,21 +13,27 @@ var (
 	_messageBox = user32.NewProc("MessageBoxW")
 )
 
-func _msgBox(primarytext string, secondarytext string, uType uint32) (result int) {
+func _msgBox(parent *Window, primarytext string, secondarytext string, uType uint32) (result int) {
 	// http://msdn.microsoft.com/en-us/library/windows/desktop/aa511267.aspx says "Use task dialogs whenever appropriate to achieve a consistent look and layout. Task dialogs require Windows Vista® or later, so they aren't suitable for earlier versions of Windows. If you must use a message box, separate the main instruction from the supplemental instruction with two line breaks."
 	text := primarytext
 	if secondarytext != "" {
 		text += "\n\n" + secondarytext
 	}
-	uType |= _MB_TASKMODAL		// make modal to every window in the program (they're all windows of the uitask, which is a single thread)
 	ptext := toUTF16(text)
 	ptitle := toUTF16(os.Args[0])
 	ret := make(chan uiret)
 	defer close(ret)
+	parenthwnd := _HWND(_NULL)
+	if parent != nil {
+		parenthwnd = parent.sysData.hwnd
+		uType |= _MB_APPLMODAL		// only for this window
+	} else {
+		uType |= _MB_TASKMODAL		// make modal to every window in the program (they're all windows of the uitask, which is a single thread)
+	}
 	uitask <- &uimsg{
 		call:		_messageBox,
 		p:		[]uintptr{
-			uintptr(_NULL),
+			uintptr(parenthwnd),
 			utf16ToArg(ptext),
 			utf16ToArg(ptitle),
 			uintptr(uType),
@@ -41,10 +47,10 @@ func _msgBox(primarytext string, secondarytext string, uType uint32) (result int
 	return int(r.ret)
 }
 
-func msgBox(primarytext string, secondarytext string) {
+func msgBox(parent *Window, primarytext string, secondarytext string) {
-	_msgBox(primarytext, secondarytext, _MB_OK)
+	_msgBox(parent, primarytext, secondarytext, _MB_OK)
 }
 
-func msgBoxError(primarytext string, secondarytext string) {
+func msgBoxError(parent *Window, primarytext string, secondarytext string) {
-	_msgBox(primarytext, secondarytext, _MB_OK | _MB_ICONERROR)
+	_msgBox(parent, primarytext, secondarytext, _MB_OK | _MB_ICONERROR)
 }

zconstants_windows_386.go

@@ -48,6 +48,7 @@ const _LB_GETTEXTLEN = 394
 const _LB_INSERTSTRING = 385
 const _LF_FACESIZE = 32
 const _MA_ACTIVATE = 1
+const _MB_APPLMODAL = 0
 const _MB_ICONERROR = 16
 const _MB_OK = 0
 const _MB_TASKMODAL = 8192

zconstants_windows_amd64.go

@@ -48,6 +48,7 @@ const _LB_GETTEXTLEN = 394
 const _LB_INSERTSTRING = 385
 const _LF_FACESIZE = 32
 const _MA_ACTIVATE = 1
+const _MB_APPLMODAL = 0
 const _MB_ICONERROR = 16
 const _MB_OK = 0
 const _MB_TASKMODAL = 8192