Minimize App to System Tray

minimize app to system tray

C# System Tray Minimize To Tray With NotifyIcon
Minimize window to system tray

Handle the form’s Resize event. In this handler, you override the
basic functionality of the Resize event to make the form minimize to
the system tray and not to the taskbar. This can be done by doing the
following in your form’s Resize event handler: Check whether the
form’s WindowState property is set to FormWindowState.Minimized. If
yes, hide your form, enable the NotifyIcon object, and show the
balloon tip that shows some information. Once the WindowState becomes
FormWindowState.Normal, disable the NotifyIcon object by setting its
Visible property to false. Now, you want the window to reappear when
you double click on the NotifyIcon object in the taskbar. For this,
handle the NotifyIcon’s MouseDoubleClick event. Here, you show the
form using the Show() method.

private void frmMain_Resize(object sender, EventArgs e)
{
    if (FormWindowState.Minimized == this.WindowState)
    {
       mynotifyicon.Visible = true;
       mynotifyicon.ShowBalloonTip(500);
       this.Hide();
    }

    else if (FormWindowState.Normal == this.WindowState)
    {
       mynotifyicon.Visible = false;
    }
}

How to minimize Windows Store app to system tray

You can't minimize Winows Store Apps into the system tray, only Windows Forms and WPF apps can do that.

You can help that happen by voting here UWP System tray support

Trouble with minimizing app to system tray

Try to call

this.Hide()

when the form is minimized, preferably in the Form.Resize event handler:

private void frmMain_Resize(object sender, EventArgs e)
{
    if (this.WindowState == FormWindowState.Minimized)
       this.Hide();
}

At some point you have to call

this.Show()

for example, in the DoubleClick handler of the NotifyIcon.

Minimize window to system tray

There is no purely SDL2 way to do this, as Cody said, Shell_NotifyIcon is the function needed to create a notification area (system tray) icon.

The code I used to get the icon is

SDL_Window *window = SDL_CreateWindow("Test", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 200, 200, SDL_WINDOW_HIDDEN);

SDL_SysWMinfo info;
SDL_VERSION(&info.version); 

NOTIFYICONDATA icon;
if (SDL_GetWindowWMInfo(window, &info))
{
    icon.uCallbackMessage = WM_USER + 1;
    icon.uFlags = NIF_ICON | NIF_TIP | NIF_MESSAGE;
    icon.hIcon = LoadIcon(NULL, IDI_INFORMATION);
    icon.cbSize = sizeof(icon);
    icon.hWnd = info.info.win.window;
    strcpy_s(icon.szTip, "Test tip");

    bool success = Shell_NotifyIcon(NIM_ADD, &icon);
}

This creates a hidden window, and an icon (using the default information icon).

To interact with this from SDL, you need to enable platform specific window management events, this is done as follows SDL_EventState(SDL_SYSWMEVENT, SDL_ENABLE);

After this, in the main event loop you must test for SDL_SYSWMEVENT, which contains information about how the user has interacted with the notification area icon. This also looks for the minimize event and hides the window which removes it from the task bar. This is achieved in the following snippet

SDL_Event e;
while (SDL_PollEvent(&e) != 0)
{
    switch (e.type)
    {
    case SDL_SYSWMEVENT:
        if (e.syswm.msg->msg.win.msg == WM_USER + 1)
        {
            if (LOWORD(e.syswm.msg->msg.win.lParam) == WM_LBUTTONDBLCLK)
            {
                SDL_ShowWindow(window);
                SDL_RestoreWindow(window);
            }
        }
        break;
    case SDL_QUIT:
        running = false;
        break;
    case SDL_WINDOWEVENT:
        if (e.window.event == SDL_WINDOWEVENT_MINIMIZED)
            SDL_HideWindow(window);
        break;
    }
}