How to hide close button in WPF window?

Question

I'm writing a modal dialog in WPF. How do I set a WPF window to not have a close button? I'd still like for its WindowState to have a normal title bar.

I found ResizeMode, WindowState, and WindowStyle, but none of those properties allow me to hide the close button but show the title bar, as in modal dialogs.

Answer 1

goto window properties set

window style = none;

u wont get close buttons...

Answer 2

After much searching for the answer to this, I worked out this simple solution that I will share here in hopes it helps others.

I set WindowStyle=0x10000000.

This sets the WS_VISIBLE (0x10000000) and WS_OVERLAPPED (0x0) values for Window Style. "Overlapped" is the necessary value to show the title bar and window border. By removing the WS_MINIMIZEBOX (0x20000), WS_MAXIMIZEBOX (0x10000), and WS_SYSMENU (0x80000) values from my style value, all the buttons from the title bar were removed, including the Close button.

Answer 3

Let the user "close" the window but really just hide it.

In the window's OnClosing event, hide the window if already visible:

    If Me.Visibility = Windows.Visibility.Visible Then
        Me.Visibility = Windows.Visibility.Hidden
        e.Cancel = True
    End If

Each time the Background thread is to be executed, re-show background UI window:

    w.Visibility = Windows.Visibility.Visible
    w.Show()

When terminating execution of program, make sure all windows are/can-be closed:

Private Sub CloseAll()
    If w IsNot Nothing Then
        w.Visibility = Windows.Visibility.Collapsed ' Tell OnClosing to really close
        w.Close()
    End If
End Sub

Answer 4

WPF doesn't have a built-in property to hide the title bar's Close button, but you can do it with a few lines of P/Invoke.

First, add these declarations to your Window class:

private const int GWL_STYLE = -16;
private const int WS_SYSMENU = 0x80000;
[DllImport("user32.dll", SetLastError = true)]
private static extern int GetWindowLong(IntPtr hWnd, int nIndex);
[DllImport("user32.dll")]
private static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);

Then put this code in the Window's Loaded event:

var hwnd = new WindowInteropHelper(this).Handle;
SetWindowLong(hwnd, GWL_STYLE, GetWindowLong(hwnd, GWL_STYLE) & ~WS_SYSMENU);

And there you go: no more Close button. You also won't have a window icon on the left side of the title bar, which means no System menu, even when you right-click the title bar -- they all go together.

Note that Alt+F4 will still close the Window. If you don't want to allow the window to close before the background thread is done, then you could also override OnClosing and set Cancel to true, as Gabe suggested.

Answer 5

The following is about disabling the close and Maximize/Minimize buttons, it does not actually remove the buttons (but it does remove the menu items!). The buttons on the title bar are drawn in a disabled/grayed state. (I'm not quite ready to take over all the functionality myself ^^)

This is slightly different than Virgoss solution in that it removes the menu items (and the trailing separator, if needed) instead of just disabling them. It differs from Joe Whites solution as it does not disable the entire system menu and so, in my case, I can keep around the Minimize button and icon.

The follow code also supports disabling the Maximize/Minimize buttons as, unlike the Close button, removing the entries from the menu does not cause the system to render the buttons "disabled" even though removing the menu entries does disable the functionality of the buttons.

It works for me. YMMV.

    using System;
    using System.Collections.Generic;
    using System.Text;

    using System.Runtime.InteropServices;
    using Window = System.Windows.Window;
    using WindowInteropHelper = System.Windows.Interop.WindowInteropHelper;
    using Win32Exception = System.ComponentModel.Win32Exception;

    namespace Channelmatter.Guppy
    {

        public class WindowUtil
        {
            const int MF_BYCOMMAND = 0x0000;
            const int MF_BYPOSITION = 0x0400;

            const uint MFT_SEPARATOR = 0x0800;

            const uint MIIM_FTYPE = 0x0100;

            [DllImport("user32", SetLastError=true)]
            private static extern uint RemoveMenu(IntPtr hMenu, uint nPosition, uint wFlags);

            [DllImport("user32", SetLastError=true)]
            private static extern IntPtr GetSystemMenu(IntPtr hWnd, bool bRevert);

            [DllImport("user32", SetLastError=true)]
            private static extern int GetMenuItemCount(IntPtr hWnd);

            [StructLayout(LayoutKind.Sequential)]
            public struct MenuItemInfo {
                public uint   cbSize;
                public uint   fMask;
                public uint   fType;
                public uint   fState;
                public uint   wID;
                public IntPtr hSubMenu;
                public IntPtr hbmpChecked;
                public IntPtr hbmpUnchecked;
                public IntPtr dwItemData; // ULONG_PTR
                public IntPtr dwTypeData;
                public uint   cch;
                public IntPtr hbmpItem;
            };

            [DllImport("user32", SetLastError=true)]
            private static extern int GetMenuItemInfo(
                IntPtr hMenu, uint uItem,
                bool fByPosition, ref MenuItemInfo itemInfo);

            public enum MenuCommand : uint
            {
                SC_CLOSE = 0xF060,
                SC_MAXIMIZE = 0xF030,
            }

            public static void WithSystemMenu (Window win, Action<IntPtr> action) {
                var interop = new WindowInteropHelper(win);
                IntPtr hMenu = GetSystemMenu(interop.Handle, false);
                if (hMenu == IntPtr.Zero) {
                    throw new Win32Exception(Marshal.GetLastWin32Error(),
                        "Failed to get system menu");
                } else {
                    action(hMenu);
                }
            }

            // Removes the menu item for the specific command.
            // This will disable and gray the Close button and disable the
            // functionality behind the Maximize/Minimuze buttons, but it won't
            // gray out the Maximize/Minimize buttons. It will also not stop
            // the default Alt+F4 behavior.
            public static void RemoveMenuItem (Window win, MenuCommand command) {
                WithSystemMenu(win, (hMenu) => {
                    if (RemoveMenu(hMenu, (uint)command, MF_BYCOMMAND) == 0) {
                        throw new Win32Exception(Marshal.GetLastWin32Error(),
                            "Failed to remove menu item");
                    }
                });
            }

            public static bool RemoveTrailingSeparator (Window win) {
                bool result = false; // Func<...> not in .NET3 :-/
                WithSystemMenu(win, (hMenu) => {
                    result = RemoveTrailingSeparator(hMenu);
                });
                return result;
            }

            // Removes the final trailing separator of a menu if it exists.
            // Returns true if a separator is removed.
            public static bool RemoveTrailingSeparator (IntPtr hMenu) {
                int menuItemCount = GetMenuItemCount(hMenu);
                if (menuItemCount < 0) {
                    throw new Win32Exception(Marshal.GetLastWin32Error(),
                        "Failed to get menu item count");
                }
                if (menuItemCount == 0) {
                    return false;
                } else {
                    uint index = (uint)(menuItemCount - 1);
                    MenuItemInfo itemInfo = new MenuItemInfo {
                        cbSize = (uint)Marshal.SizeOf(typeof(MenuItemInfo)),
                        fMask = MIIM_FTYPE,
                    };

                    if (GetMenuItemInfo(hMenu, index, true, ref itemInfo) == 0) {
                        throw new Win32Exception(Marshal.GetLastWin32Error(),
                            "Failed to get menu item info");
                    }

                    if (itemInfo.fType == MFT_SEPARATOR) {
                        if (RemoveMenu(hMenu, index, MF_BYPOSITION) == 0) {
                            throw new Win32Exception(Marshal.GetLastWin32Error(),
                                "Failed to remove menu item");
                        }
                        return true;
                    } else {
                        return false;
                    }
                }
            }

            private const int GWL_STYLE = -16;

            [Flags]
            public enum WindowStyle : int
            {
                WS_MINIMIZEBOX = 0x00020000,
                WS_MAXIMIZEBOX = 0x00010000,
            }

            // Don't use this version for dealing with pointers
            [DllImport("user32", SetLastError=true)]
            private static extern int SetWindowLong (IntPtr hWnd, int nIndex, int dwNewLong);

            // Don't use this version for dealing with pointers
            [DllImport("user32", SetLastError=true)]
            private static extern int GetWindowLong (IntPtr hWnd, int nIndex);

            public static int AlterWindowStyle (Window win,
                WindowStyle orFlags, WindowStyle andNotFlags) 
            {
                var interop = new WindowInteropHelper(win);

                int prevStyle = GetWindowLong(interop.Handle, GWL_STYLE);
                if (prevStyle == 0) {
                    throw new Win32Exception(Marshal.GetLastWin32Error(),
                        "Failed to get window style");
                }

                int newStyle = (prevStyle | (int)orFlags) & ~((int)andNotFlags);
                if (SetWindowLong(interop.Handle, GWL_STYLE, newStyle) == 0) {
                    throw new Win32Exception(Marshal.GetLastWin32Error(),
                        "Failed to set window style");
                }
                return prevStyle;
            }

            public static int DisableMaximizeButton (Window win) {
                return AlterWindowStyle(win, 0, WindowStyle.WS_MAXIMIZEBOX);
            }
        }
    }

Usage: This must be done AFTER the source is initialized. A good place is to use the SourceInitialized event of the Window:

Window win = ...; /* the Window :-) */
WindowUtil.DisableMaximizeButton(win);
WindowUtil.RemoveMenuItem(win, WindowUtil.MenuCommand.SC_MAXIMIZE);
WindowUtil.RemoveMenuItem(win, WindowUtil.MenuCommand.SC_CLOSE);
while (WindowUtil.RemoveTrailingSeparator(win)) 
{
   //do it here
}

To disable the Alt+F4 functionality the easy method is just to wire up the Canceling event and use set a flag for when you really do want to close the window.

Answer 6

As stated in other answers, you can use WindowStyle="None" to remove the Title Bar altogether.

And, as stated in the comments to those other answers, this prevents the window from being draggable so it is hard to move it from its initial position.

However, you can overcome this by adding a single line of code to the Constructor in the Window's Code Behind file:

MouseDown += delegate { DragMove(); };

Or, if you prefer Lambda Syntax:

MouseDown += (sender, args) => DragMove();

This makes the entire Window draggable. Any interactive controls present in the Window, such as Buttons, will still work as normal and won't act as drag-handles for the Window.