From f34c68611388e0770c4b8b9776b35f98c4c4d05b Mon Sep 17 00:00:00 2001
From: Angelo Steinbach <angelo.steinbach@outlook.de>
Date: Mon, 31 Oct 2016 08:45:30 +0100
Subject: [PATCH] Added SetBalloonIcon to NotifyIcon for support of custom
 balloon icons. Compatibility of NotifyIcon is changed to Vista if on Vista or
 higher to support custom balloon icon. Works also with Windows compatibility
 mode.

---
 notifyicon.go | 36 ++++++++++++++++++++++++++++++++++--
 1 file changed, 34 insertions(+), 2 deletions(-)

diff --git a/notifyicon.go b/notifyicon.go
index fe4ef8bf..f6d8e3a4 100644
--- a/notifyicon.go
+++ b/notifyicon.go
@@ -13,6 +13,7 @@ import (
 
 import (
 	"github.com/lxn/win"
+	"errors"
 )
 
 const notifyIconWindowClass = `\o/ Walk_NotifyIcon_Class \o/`
@@ -78,6 +79,8 @@ type NotifyIcon struct {
 	hWnd               win.HWND
 	contextMenu        *Menu
 	icon               *Icon
+	uVersion           uint32
+	balloonIcon        *Icon
 	toolTip            string
 	visible            bool
 	mouseDownPublisher MouseEventPublisher
@@ -120,8 +123,14 @@ func NewNotifyIcon() (*NotifyIcon, error) {
 		return nil, newError("Shell_NotifyIcon")
 	}
 
-	// We want XP-compatible message behavior.
-	nid.UVersion = win.NOTIFYICON_VERSION
+
+	// We want XP-compatible message behavior or vista+ when available.
+	uVersion := win.NOTIFYICON_VERSION_XP
+	if win.LOBYTE(win.LOWORD(win.GetVersion())) >= 6 {
+		uVersion = win.NOTIFYICON_VERSION_VISTA
+	}
+
+	nid.UVersion = uVersion
 
 	if !win.Shell_NotifyIcon(win.NIM_SETVERSION, &nid) {
 		return nil, newError("Shell_NotifyIcon")
@@ -137,6 +146,7 @@ func NewNotifyIcon() (*NotifyIcon, error) {
 		id:          nid.UID,
 		hWnd:        hWnd,
 		contextMenu: menu,
+		uVersion: uVersion,
 	}
 
 	// Set our *NotifyIcon as user data for the message window.
@@ -260,6 +270,28 @@ func (ni *NotifyIcon) SetIcon(icon *Icon) error {
 	return nil
 }
 
+// SetBalloonIcon sets the Icon of the custom message.
+func (ni *NotifyIcon) SetBalloonIcon(icon *Icon) error {
+	if ni.uVersion < win.NOTIFYICON_VERSION_VISTA{
+		return errors.New("Custom balloon icon is only supported on Windows Vista and higher!")
+	}
+
+	if icon == ni.balloonIcon {
+		return nil
+	}
+
+	nid := ni.notifyIconData()
+	if icon == nil {
+		nid.Set_hBalloonIcon(0)
+	} else {
+		nid.Set_hBalloonIcon(icon.hIcon)
+	}
+
+	ni.balloonIcon = icon
+
+	return nil
+}
+
 // ToolTip returns the tool tip text of the NotifyIcon.
 func (ni *NotifyIcon) ToolTip() string {
 	return ni.toolTip