Show a Form without stealing focus?

Question

I'm using a Form to show notifications (it appears at the bottom right of the screen), but when I show this form it steals the focus from the main Form. Is there a way to show this "notification" form without stealing focus?

Answer 1

This is what worked for me. It provides TopMost but without focus-stealing.

    protected override bool ShowWithoutActivation
    {
       get { return true; }
    }

    private const int WS_EX_TOPMOST = 0x00000008;
    protected override CreateParams CreateParams
    {
       get
       {
          CreateParams createParams = base.CreateParams;
          createParams.ExStyle |= WS_EX_TOPMOST;
          return createParams;
       }
    }

Remember to omit setting TopMost in Visual Studio designer, or elsewhere.

This is stolen, err, borrowed, from here (click on Workarounds):

https://connect.microsoft.com/VisualStudio/feedback/details/401311/showwithoutactivation-is-not-supported-with-topmost

Answer 2

I needed to do this with my window TopMost. I implemented the PInvoke method above but found that my Load event wasn't getting called like Talha above. I finally succeeded. Maybe this will help someone. Here is my solution:

        form.Visible = false;
        form.TopMost = false;
        ShowWindow(form.Handle, ShowNoActivate);
        SetWindowPos(form.Handle, HWND_TOPMOST,
            form.Left, form.Top, form.Width, form.Height,
            NoActivate);
        form.Visible = true;    //So that Load event happens

Answer 3

This works well.

See: OpenIcon - MSDN and SetForegroundWindow - MSDN

using System.Runtime.InteropServices;

[DllImport("user32.dll")]
static extern bool OpenIcon(IntPtr hWnd);

[DllImport("user32.dll")]
static extern bool SetForegroundWindow(IntPtr hWnd);

public static void ActivateInstance()
{
    IntPtr hWnd = IntPtr hWnd = Process.GetCurrentProcess().MainWindowHandle;

    // Restore the program.
    bool result = OpenIcon(hWnd); 
    // Activate the application.
    result = SetForegroundWindow(hWnd);

    // End the current instance of the application.
    //System.Environment.Exit(0);    
}

Answer 4

I don't know if this is considered as necro-posting, but this is what I did since I couln't get it working with user32's "ShowWindow" and "SetWindowPos" methods. And no, overriding "ShowWithoutActivation" doesn't work in this case since the new window should be always-on-top. Anyway, I created a helper method that takes a form as parameter; when called, it shows the form, brings it to the front and makes it TopMost without stealing the focus of the current window (apparently it does, but the user won't notice).

    [DllImport("user32.dll")]
    static extern IntPtr GetForegroundWindow();

    [DllImport("user32.dll")]
    static extern IntPtr SetForegroundWindow(IntPtr hWnd);

    public static void ShowTopmostNoFocus(Form f)
    {
        IntPtr activeWin = GetForegroundWindow();

        f.Show();
        f.BringToFront();
        f.TopMost = true;

        if (activeWin.ToInt32() > 0)
        {
            SetForegroundWindow(activeWin);
        }
    }

Answer 5

In WPF you can solve it like this:

In the window put these attributes:

<Window
    x:Class="myApplication.winNotification"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  Title="Notification Popup" Width="300" SizeToContent="Height"
  WindowStyle="None" AllowsTransparency="True" Background="Transparent" ShowInTaskbar="False" Topmost="True" Focusable="False" ShowActivated="False" >
</Window>

The last one attribute is the one you need ShowActivated="False".

Answer 6

You might want to consider what kind of notification you would like to display.

If it's absolutely critical to let the user know about some event, using Messagebox.Show would be the recommended way, due to its nature to block any other events to the main window, until the user confirms it. Be aware of pop-up blindness, though.

If it's less than critical, you might want to use an alternative way to display notifications, such as a toolbar on the bottom of the window. You wrote, that you display notifications on the bottom-right of the screen - the standard way to do this would be using a balloon tip with the combination of a system tray icon.