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.
XAML Code
<Button Command="Open" Content="_Open">
<Button.Style>
<Style TargetType="Button">
<Style.Triggers>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Visibility" Value="Collapsed" />
</Trigger>
</Style.Triggers>
</Style>
</Button.Style>
</Button>
should work
Edit- for your instant this Thread shows how that can be done but I don't think Window has a property to get what you want without losing the normal title bar.
Edit 2 This Thread shows a way for it to be done, but you must apply your own style to the system menu and it shows a way how you can do that.
Does your modal dialog have a cancel button? If so, could you treat hitting the close button the same as pressing Cancel?
So, pretty much here is your problem. The close button on the upper right of a window frame is not part of the WPF window, but it belongs to the part of the window frame that is controled by your OS. This means you will have to use Win32 interop to do it.
alternativly, you can use the noframe and either provide your own "frame" or have no frame at all.
This wont get rid of the close button but it will stop someone closing the window
put this in your code behind file
protected override void OnClosing(CancelEventArgs e)
{
base.OnClosing(e);
e.Cancel = true;
}
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.
To disable close button you should add the following code to your Window class (the code was taken from here, edited and reformatted a bit):
protected override void OnSourceInitialized(EventArgs e)
{
base.OnSourceInitialized(e);
HwndSource hwndSource = PresentationSource.FromVisual(this) as HwndSource;
if (hwndSource != null)
{
hwndSource.AddHook(HwndSourceHook);
}
}
private bool allowClosing = false;
[DllImport("user32.dll")]
private static extern IntPtr GetSystemMenu(IntPtr hWnd, bool bRevert);
[DllImport("user32.dll")]
private static extern bool EnableMenuItem(IntPtr hMenu, uint uIDEnableItem, uint uEnable);
private const uint MF_BYCOMMAND = 0x00000000;
private const uint MF_GRAYED = 0x00000001;
private const uint SC_CLOSE = 0xF060;
private const int WM_SHOWWINDOW = 0x00000018;
private const int WM_CLOSE = 0x10;
private IntPtr HwndSourceHook(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
switch (msg)
{
case WM_SHOWWINDOW:
{
IntPtr hMenu = GetSystemMenu(hwnd, false);
if (hMenu != IntPtr.Zero)
{
EnableMenuItem(hMenu, SC_CLOSE, MF_BYCOMMAND | MF_GRAYED);
}
}
break;
case WM_CLOSE:
if (!allowClosing)
{
handled = true;
}
break;
}
return IntPtr.Zero;
}
This code also disables close item in System menu and disallows closing the dialog using Alt+F4.
You will probably want to close the window programmatically. Just calling Close() will not work. Do something like this:
allowClosing = true;
Close();
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
}
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.
Hi, I just got to similar problem and Joe White's solusion seems to me simple and clean. I reused it and defined it as an attached property of Window
public class WindowBehavior
{
private static readonly Type OwnerType = typeof (WindowBehavior);
#region HideCloseButton (attached property)
public static readonly DependencyProperty HideCloseButtonProperty =
DependencyProperty.RegisterAttached(
"HideCloseButton",
typeof (bool),
OwnerType,
new FrameworkPropertyMetadata(false, new PropertyChangedCallback(HideCloseButtonChangedCallback)));
[AttachedPropertyBrowsableForType(typeof(Window))]
public static bool GetHideCloseButton(Window obj) {
return (bool)obj.GetValue(HideCloseButtonProperty);
}
[AttachedPropertyBrowsableForType(typeof(Window))]
public static void SetHideCloseButton(Window obj, bool value) {
obj.SetValue(HideCloseButtonProperty, value);
}
private static void HideCloseButtonChangedCallback(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var window = d as Window;
if (window == null) return;
var hideCloseButton = (bool)e.NewValue;
if (hideCloseButton && !GetIsHiddenCloseButton(window)) {
if (!window.IsLoaded) {
window.Loaded += LoadedDelegate;
}
else {
HideCloseButton(window);
}
SetIsHiddenCloseButton(window, true);
}
else if (!hideCloseButton && GetIsHiddenCloseButton(window)) {
if (!window.IsLoaded) {
window.Loaded -= LoadedDelegate;
}
else {
ShowCloseButton(window);
}
SetIsHiddenCloseButton(window, false);
}
}
#region Win32 imports
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);
#endregion
private static readonly RoutedEventHandler LoadedDelegate = (sender, args) => {
if (sender is Window == false) return;
var w = (Window)sender;
HideCloseButton(w);
w.Loaded -= LoadedDelegate;
};
private static void HideCloseButton(Window w) {
var hwnd = new WindowInteropHelper(w).Handle;
SetWindowLong(hwnd, GWL_STYLE, GetWindowLong(hwnd, GWL_STYLE) & ~WS_SYSMENU);
}
private static void ShowCloseButton(Window w) {
var hwnd = new WindowInteropHelper(w).Handle;
SetWindowLong(hwnd, GWL_STYLE, GetWindowLong(hwnd, GWL_STYLE) | WS_SYSMENU);
}
#endregion
#region IsHiddenCloseButton (readonly attached property)
private static readonly DependencyPropertyKey IsHiddenCloseButtonKey =
DependencyProperty.RegisterAttachedReadOnly(
"IsHiddenCloseButton",
typeof (bool),
OwnerType,
new FrameworkPropertyMetadata(false));
public static readonly DependencyProperty IsHiddenCloseButtonProperty =
IsHiddenCloseButtonKey.DependencyProperty;
[AttachedPropertyBrowsableForType(typeof(Window))]
public static bool GetIsHiddenCloseButton(Window obj) {
return (bool)obj.GetValue(IsHiddenCloseButtonProperty);
}
private static void SetIsHiddenCloseButton(Window obj, bool value) {
obj.SetValue(IsHiddenCloseButtonKey, value);
}
#endregion
}
Then in XAML you just set it like this:
<Window
x:Class="WafClient.Presentation.Views.SampleWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:u="clr-namespace:WafClient.Presentation.Behaviors"
ResizeMode="NoResize"
u:WindowBehavior.HideCloseButton="True">
...
</Window>
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