Can you send a signal to Windows Explorer to make it refresh the systray icons?

This problem has been afflicting me for quite a while and it's been really annoying.

Every time I login after a reboot/power cycle the explorer takes some time to show up. I've taken the step of waiting for all the services to boot up and then I login, but it doesn't make any difference. The result is always the same: Some of the icons do not show up even if the applications have started.

I've dug a bit on the code that makes one application "stick" an icon in there, but is there an API call that one can perform so explorer re-reads all that icon info? Like invalidate or redraw or something of the sort?

Apparently, it looks like Jon was right and it's not possible to do it.

I've followed Bob Dizzle and Mark Ransom code and build this (Delphi Code):

procedure Refresh;
var
  hSysTray: THandle;
begin
  hSysTray := GetSystrayHandle;
  SendMessage(hSysTray, WM_PAINT, 0, 0);
end;

function GetSystrayHandle: THandle;
var
  hTray, hNotify, hSysPager: THandle;
begin
  hTray := FindWindow('Shell_TrayWnd', '');
  if hTray = 0 then
  begin
    Result := hTray;
    exit;
  end;

  hNotify := FindWindowEx(hTray, 0, 'TrayNotifyWnd', '');
  if hNotify = 0 then
  begin
    Result := hNotify;
    exit;
  end;

  hSyspager := FindWindowEx(hNotify, 0, 'SysPager', '');
  if hSyspager = 0 then
  begin
    Result := hSyspager;
    exit;
  end;

  Result := FindWindowEx(hSysPager, 0, 'ToolbarWindow32', 'Notification Area');
end;

But to no avail.

I've even tried with

InvalidateRect()

Any other suggestions?

Solution 1:

Take a look at this blog entry: REFRESHING THE TASKBAR NOTIFICATION AREA. I am using this code to refresh the system tray to get rid of orphaned icons and it works perfectly. The blog entry is very informative and gives a great explanation of the steps the author performed to discover his solution.

#define FW(x,y) FindWindowEx(x, NULL, y, L"")

void RefreshTaskbarNotificationArea()
{
    HWND hNotificationArea;
    RECT r;

    GetClientRect(
        hNotificationArea = FindWindowEx(
            FW(FW(FW(NULL, L"Shell_TrayWnd"), L"TrayNotifyWnd"), L"SysPager"),
            NULL,
            L"ToolbarWindow32",
            // L"Notification Area"), // Windows XP
            L"User Promoted Notification Area"), // Windows 7 and up
        &r);

    for (LONG x = 0; x < r.right; x += 5)
        for (LONG y = 0; y < r.bottom; y += 5)
            SendMessage(
                hNotificationArea,
                WM_MOUSEMOVE,
                0,
                (y << 16) + x);
}

Solution 2:

Two important details for anyone using Louis's answer (from REFRESHING THE TASKBAR NOTIFICATION AREA) on Windows 7 or Windows 8:

First, as the answer was reflected to show, the window titled "Notification Area" in XP is now titled "User Promoted Notification Area" in Windows 7 (actually probably Vista) and up.

Second, this code does not clear icons that are currently hidden. These are contained in a separate window. Use the original code to refresh visible icons, and the following to refresh hidden icons.

//Hidden icons
GetClientRect(
    hNotificationArea = FindWindowEx(
        FW(NULL, L"NotifyIconOverflowWindow"),
        NULL,
        L"ToolbarWindow32",
        L"Overflow Notification Area"),
    &r);

for (LONG x = 0; x < r.right; x += 5)
    for (LONG y = 0; y < r.bottom; y += 5)
        SendMessage(
            hNotificationArea,
            WM_MOUSEMOVE,
            0,
            (y << 16) + x);

For anyone who just needs a utility to run to accomplish this, rather than code, I built a simple exe with this update: Refresh Notification Area