If user double-clicks window title bar to maximize window, the window will maximize on MouseDown event of the second click, but then the MouseUp event on that same second click will be registered by one of the controls in the window that are now under the cursor and trigger something user didn't want.
How can it be prevented?
This should work just fine:
Solution:
//WNDPROC INTEROP
private const int WM_NCLBUTTONDBLCLK = 0x00A3;
protected override void OnSourceInitialized(EventArgs e)
{
base.OnSourceInitialized(e);
HwndSource source = PresentationSource.FromVisual(this) as HwndSource;
source.AddHook(WndProc);
}
private IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
//TITLE BAR DOUBLE CLICK
if (msg == WM_NCLBUTTONDBLCLK)
{
Console.WriteLine("titlebar double click " + this.WindowState);
//WINDOW ABOUT TO GET MAXIMIZED
if (msg == WM_NCLBUTTONDBLCLK)
handleNextMouseup = true;
else if (msg == 0x202) // mouseup
{
if (handleNextMouseup)
handled = true;
handleNextMouseup = false;
}
}
return IntPtr.Zero;
}
another possible solution:
//WNDPROC INTEROP
private const int WM_NCLBUTTONDBLCLK = 0x00A3;
protected override void OnSourceInitialized(EventArgs e)
{
base.OnSourceInitialized(e);
HwndSource source = PresentationSource.FromVisual(this) as HwndSource;
source.AddHook(WndProc);
}
private IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
//TITLE BAR DOUBLE CLICK
if (msg == WM_NCLBUTTONDBLCLK)
{
Console.WriteLine("titlebar double click " + this.WindowState);
//WINDOW ABOUT TO GET MAXIMIZED
if (this.WindowState == WindowState.Normal)
{
fakehittestvisible = true;
}
}
return IntPtr.Zero;
}
private bool fakehittestvisible = false;
//ON PREVIEW MOUSE UP ABORT IF MIXIMIZING HAPPENED
private void this_PreviewMouseUp(object sender, MouseButtonEventArgs e)
{
if (fakehittestvisible)
{
e.Handled = true;
fakehittestvisible = false;
return;
}
fakehittestvisible = false;
Console.WriteLine("this mouse up state is " + this.WindowState);
}
I need to execute a code when shutdown/logoff. When any of these action are made im getting an application error with code 0xe0434352. What im doing wrong?
This is my code:
private void Window_SourceInitialized(object sender, EventArgs e)
{
IntPtr windowHandle = (new WindowInteropHelper(this)).Handle;
HwndSource src = HwndSource.FromHwnd(windowHandle);
src.AddHook(new HwndSourceHook(WndProc));
}
private IntPtr WndProc(IntPtr hWnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
if (msg == 0x0011)
{
EventLog.WriteEntry("WPF1", "finally!");
//my code
}
return IntPtr.Zero;
}
private void Window_Closing(object sender, System.ComponentModel.CancelEventArgs e)
{
IntPtr windowHandle = (new WindowInteropHelper(this)).Handle;
HwndSource src = HwndSource.FromHwnd(windowHandle);
src.RemoveHook(new HwndSourceHook(this.WndProc));
}
Exception error: http://pastebin.com/gaX0ekaP
Nevermind, admin priviledges were required.
There are two problems with WPF windows when the WindowStyle=None option is used.
The window covers the Taskbar when maximized.
Once maximized, the window cannot be dragged down to unmaximize.
How can these problems be corrected?
Preferably without using Windows.Forms.
There are other answers to these problems online. However none of them take into acount how the solution will perform on setups with multiple monitors. Especially if the primary monitor is not the left-most in the setup.
I designed this code taking into account single and multiple monitors setups.
This solution also does not bring in Windows.Forms as a reference, it uses unmanagaged calls.
XAML
<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Background="AliceBlue" WindowStyle="None" Height="350" Width="525" SourceInitialized="Window_SourceInitialized">
<Grid>
<Rectangle Name="rctHeader" Height="40" VerticalAlignment="Top" Fill="CadetBlue" PreviewMouseLeftButtonDown="rctHeader_PreviewMouseLeftButtonDown" PreviewMouseLeftButtonUp="rctHeader_PreviewMouseLeftButtonUp" PreviewMouseMove="rctHeader_PreviewMouseMove"/>
</Grid>
</Window>
Code Behind
using System.Runtime.InteropServices;
using System.Windows.Interop;
private bool mRestoreIfMove = false;
public MainWindow()
{
InitializeComponent();
}
void Window_SourceInitialized(object sender, EventArgs e)
{
IntPtr mWindowHandle = (new WindowInteropHelper(this)).Handle;
HwndSource.FromHwnd(mWindowHandle).AddHook(new HwndSourceHook(WindowProc));
}
private static System.IntPtr WindowProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
switch (msg)
{
case 0x0024:
WmGetMinMaxInfo(hwnd, lParam);
break;
}
return IntPtr.Zero;
}
private static void WmGetMinMaxInfo(System.IntPtr hwnd, System.IntPtr lParam)
{
POINT lMousePosition;
GetCursorPos(out lMousePosition);
IntPtr lPrimaryScreen = MonitorFromPoint(new POINT(0, 0), MonitorOptions.MONITOR_DEFAULTTOPRIMARY);
MONITORINFO lPrimaryScreenInfo = new MONITORINFO();
if (GetMonitorInfo(lPrimaryScreen, lPrimaryScreenInfo) == false)
{
return;
}
IntPtr lCurrentScreen = MonitorFromPoint(lMousePosition, MonitorOptions.MONITOR_DEFAULTTONEAREST);
MINMAXINFO lMmi = (MINMAXINFO)Marshal.PtrToStructure(lParam, typeof(MINMAXINFO));
if (lPrimaryScreen.Equals(lCurrentScreen) == true)
{
lMmi.ptMaxPosition.X = lPrimaryScreenInfo.rcWork.Left;
lMmi.ptMaxPosition.Y = lPrimaryScreenInfo.rcWork.Top;
lMmi.ptMaxSize.X = lPrimaryScreenInfo.rcWork.Right - lPrimaryScreenInfo.rcWork.Left;
lMmi.ptMaxSize.Y = lPrimaryScreenInfo.rcWork.Bottom - lPrimaryScreenInfo.rcWork.Top;
}
else
{
lMmi.ptMaxPosition.X = lPrimaryScreenInfo.rcMonitor.Left;
lMmi.ptMaxPosition.Y = lPrimaryScreenInfo.rcMonitor.Top;
lMmi.ptMaxSize.X = lPrimaryScreenInfo.rcMonitor.Right - lPrimaryScreenInfo.rcMonitor.Left;
lMmi.ptMaxSize.Y = lPrimaryScreenInfo.rcMonitor.Bottom - lPrimaryScreenInfo.rcMonitor.Top;
}
Marshal.StructureToPtr(lMmi, lParam, true);
}
private void SwitchWindowState()
{
switch (WindowState)
{
case WindowState.Normal:
{
WindowState = WindowState.Maximized;
break;
}
case WindowState.Maximized:
{
WindowState = WindowState.Normal;
break;
}
}
}
private void rctHeader_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
if (e.ClickCount == 2)
{
if ((ResizeMode == ResizeMode.CanResize) || (ResizeMode == ResizeMode.CanResizeWithGrip))
{
SwitchWindowState();
}
return;
}
else if (WindowState == WindowState.Maximized)
{
mRestoreIfMove = true;
return;
}
DragMove();
}
private void rctHeader_PreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
mRestoreIfMove = false;
}
private void rctHeader_PreviewMouseMove(object sender, MouseEventArgs e)
{
if (mRestoreIfMove)
{
mRestoreIfMove = false;
double percentHorizontal = e.GetPosition(this).X / ActualWidth;
double targetHorizontal = RestoreBounds.Width * percentHorizontal;
double percentVertical = e.GetPosition(this).Y / ActualHeight;
double targetVertical = RestoreBounds.Height * percentVertical;
WindowState = WindowState.Normal;
POINT lMousePosition;
GetCursorPos(out lMousePosition);
Left = lMousePosition.X - targetHorizontal;
Top = lMousePosition.Y - targetVertical;
DragMove();
}
}
[DllImport("user32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool GetCursorPos(out POINT lpPoint);
[DllImport("user32.dll", SetLastError = true)]
static extern IntPtr MonitorFromPoint(POINT pt, MonitorOptions dwFlags);
enum MonitorOptions : uint
{
MONITOR_DEFAULTTONULL = 0x00000000,
MONITOR_DEFAULTTOPRIMARY = 0x00000001,
MONITOR_DEFAULTTONEAREST = 0x00000002
}
[DllImport("user32.dll")]
static extern bool GetMonitorInfo(IntPtr hMonitor, MONITORINFO lpmi);
[StructLayout(LayoutKind.Sequential)]
public struct POINT
{
public int X;
public int Y;
public POINT(int x, int y)
{
this.X = x;
this.Y = y;
}
}
[StructLayout(LayoutKind.Sequential)]
public struct MINMAXINFO
{
public POINT ptReserved;
public POINT ptMaxSize;
public POINT ptMaxPosition;
public POINT ptMinTrackSize;
public POINT ptMaxTrackSize;
};
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
public class MONITORINFO
{
public int cbSize = Marshal.SizeOf(typeof(MONITORINFO));
public RECT rcMonitor = new RECT();
public RECT rcWork = new RECT();
public int dwFlags = 0;
}
[StructLayout(LayoutKind.Sequential)]
public struct RECT
{
public int Left, Top, Right, Bottom;
public RECT(int left, int top, int right, int bottom)
{
this.Left = left;
this.Top = top;
this.Right = right;
this.Bottom = bottom;
}
}
I have a nice quick and dirty solution. Try following code when maximize your none bordered window:
if (WindowState == WindowState.Normal)
{
WindowStyle = WindowStyle.SingleBorderWindow;
WindowState = WindowState.Maximized;
WindowStyle = WindowStyle.None;
}
The trick is to set the WindowStyle to SingleBorderWindow then maximize the window and set it back to None.
Such a nice code leebickmtu!
I had a little issue with multiple monitors, in windows 10 : since there is a taskBar on each screen, if you maximize your window on a secondary screen his taskbar become hidden.
I just modify a bit this method, in order to have relative position from any screen :
private static void WmGetMinMaxInfo(System.IntPtr hwnd, System.IntPtr lParam)
{
POINT lMousePosition;
GetCursorPos(out lMousePosition);
IntPtr lCurrentScreen = MonitorFromPoint(lMousePosition, MonitorOptions.MONITOR_DEFAULTTONEAREST);
MINMAXINFO lMmi = (MINMAXINFO)Marshal.PtrToStructure(lParam, typeof(MINMAXINFO));
MONITORINFO lCurrentScreenInfo = new MONITORINFO();
if (GetMonitorInfo(lCurrentScreen, lCurrentScreenInfo) == false)
{
return;
}
//Position relative pour notre fenĂȘtre
lMmi.ptMaxPosition.X = lCurrentScreenInfo.rcWork.Left - lCurrentScreenInfo.rcMonitor.Left;
lMmi.ptMaxPosition.Y = lCurrentScreenInfo.rcWork.Top - lCurrentScreenInfo.rcMonitor.Top;
lMmi.ptMaxSize.X = lCurrentScreenInfo.rcWork.Right - lCurrentScreenInfo.rcWork.Left;
lMmi.ptMaxSize.Y = lCurrentScreenInfo.rcWork.Bottom - lCurrentScreenInfo.rcWork.Top;
Marshal.StructureToPtr(lMmi, lParam, true);
}
Hope this help...
leebickmtu's answer is basically correct, but has some extraneous code and picks the monitor based one where the cursor is, rather than where the window is. That would have the wrong behavior if the mouse is on a different monitor and the user presses Win+Up to maximize. We should be using MonitorFromWindow to identify the monitor to maximize to.
Put the following in your window codebehind:
protected override void OnSourceInitialized(EventArgs e)
{
base.OnSourceInitialized(e);
((HwndSource)PresentationSource.FromVisual(this)).AddHook(HookProc);
}
public static IntPtr HookProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
if (msg == WM_GETMINMAXINFO)
{
// We need to tell the system what our size should be when maximized. Otherwise it will
// cover the whole screen, including the task bar.
MINMAXINFO mmi = (MINMAXINFO)Marshal.PtrToStructure(lParam, typeof(MINMAXINFO));
// Adjust the maximized size and position to fit the work area of the correct monitor
IntPtr monitor = MonitorFromWindow(hwnd, MONITOR_DEFAULTTONEAREST);
if (monitor != IntPtr.Zero)
{
MONITORINFO monitorInfo = new MONITORINFO();
monitorInfo.cbSize = Marshal.SizeOf(typeof(MONITORINFO));
GetMonitorInfo(monitor, ref monitorInfo);
RECT rcWorkArea = monitorInfo.rcWork;
RECT rcMonitorArea = monitorInfo.rcMonitor;
mmi.ptMaxPosition.X = Math.Abs(rcWorkArea.Left - rcMonitorArea.Left);
mmi.ptMaxPosition.Y = Math.Abs(rcWorkArea.Top - rcMonitorArea.Top);
mmi.ptMaxSize.X = Math.Abs(rcWorkArea.Right - rcWorkArea.Left);
mmi.ptMaxSize.Y = Math.Abs(rcWorkArea.Bottom - rcWorkArea.Top);
}
Marshal.StructureToPtr(mmi, lParam, true);
}
return IntPtr.Zero;
}
private const int WM_GETMINMAXINFO = 0x0024;
private const uint MONITOR_DEFAULTTONEAREST = 0x00000002;
[DllImport("user32.dll")]
private static extern IntPtr MonitorFromWindow(IntPtr handle, uint flags);
[DllImport("user32.dll")]
private static extern bool GetMonitorInfo(IntPtr hMonitor, ref MONITORINFO lpmi);
[Serializable]
[StructLayout(LayoutKind.Sequential)]
public struct RECT
{
public int Left;
public int Top;
public int Right;
public int Bottom;
public RECT(int left, int top, int right, int bottom)
{
this.Left = left;
this.Top = top;
this.Right = right;
this.Bottom = bottom;
}
}
[StructLayout(LayoutKind.Sequential)]
public struct MONITORINFO
{
public int cbSize;
public RECT rcMonitor;
public RECT rcWork;
public uint dwFlags;
}
[Serializable]
[StructLayout(LayoutKind.Sequential)]
public struct POINT
{
public int X;
public int Y;
public POINT(int x, int y)
{
this.X = x;
this.Y = y;
}
}
[StructLayout(LayoutKind.Sequential)]
public struct MINMAXINFO
{
public POINT ptReserved;
public POINT ptMaxSize;
public POINT ptMaxPosition;
public POINT ptMinTrackSize;
public POINT ptMaxTrackSize;
}
If only one monitor is used another simple approach is to set the maximum height of the window. The System.Windows.SystemParameters class provides some usefull values e.g. PrimaryScreenHeight or MaximizedPrimaryScreenHeight.
In my sample code i use MaximizedPrimaryScreenHeight and subtract the ResizeBorderThickness i set in WindowChrome.
using System.Windows;
using System.Windows.Shell;
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
Thickness resizeBorderThickness = WindowChrome.GetWindowChrome(this).ResizeBorderThickness;
this.MaxHeight = SystemParameters.MaximizedPrimaryScreenHeight - resizeBorderThickness.Top - resizeBorderThickness.Bottom;
}
}
Building on Dennis' excellent solution:
private void MainWindow_Loaded(object sender, RoutedEventArgs e)
{
HandleWinMaximized();
StateChanged += MainWindow_StateChanged;
}
private void MainWindow_StateChanged(object sender, EventArgs e)
{
HandleWinMaximized();
}
private void HandleWinMaximized()
{
if (WindowState == WindowState.Maximized)
{
WindowStyle = WindowStyle.SingleBorderWindow;
WindowStyle = WindowStyle.None;
}
}
I'm trying to anchor a WPF Window (NOT a control inside a window) to TopRight for example, by default Windows anchors all windows to top left.
I tried the following code
private void OnWindowSizeChanged(object sender, SizeChangedEventArgs e)
{
double delta = e.PreviousSize.Width - e.NewSize.Width;
Left += delta;
}
It works, but the window stutters/flickers during rapid size changes (e.g Animations)
I tried googling it but did not find a good solution, am I missing something ?
I managed to solve the problem with the help of this post.
Here's the code
public partial class MainWindow : Window
{
private double right;
public MainWindow()
{
InitializeComponent();
}
protected override void OnSourceInitialized(EventArgs e)
{
base.OnSourceInitialized(e);
HwndSource source = PresentationSource.FromVisual(this) as HwndSource;
right = Left + Width;
source.AddHook(WndProc);
}
private IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
if (msg == (int)WindowMessage.WindowPositionChanging)
{
var windowPosition = (WindowPosition)Marshal.PtrToStructure(lParam, typeof(WindowPosition));
bool isMove = !windowPosition.Flags.HasFlag(WindowPositionFlags.NoMove); //0x0002
bool isSize = !windowPosition.Flags.HasFlag(WindowPositionFlags.NoSize); //0x0001
if (isMove)
{
right = windowPosition.Left + windowPosition.Width;
}
else if (isSize)
{
windowPosition.Left = (int)(right - windowPosition.Width);
windowPosition.Top = (int)Top;
windowPosition.Flags = (WindowPositionFlags)((int)windowPosition.Flags & 0xfffd); //remove the NoMove flag
Marshal.StructureToPtr(windowPosition, lParam, true);
}
}
return IntPtr.Zero;
}
Hope it helps someone
If I use dragMove the wpf window will not move to a location where the y value is negative. I can however set the windows top value to a negative value. Is there a simple way to enable dragMove to allow the top of the window to be moved above the displays 0 position?
Edit:
It seems that this is the default window's handling of moveWindow. Verified with a call to SendMessage( hwnd, WM_SYSCOMMAND, SC_MOVE, null);
As I found, the window will move to "negative" location, but will then jump back. To prevent this you could do something like:
public partial class Window1: Window {
public Window1() {
InitializeComponent();
}
private void Window_MouseDown(object sender, MouseButtonEventArgs e) {
DragMove();
}
public struct WINDOWPOS {
public IntPtr hwnd;
public IntPtr hwndInsertAfter;
public int x;
public int y;
public int cx;
public int cy;
public UInt32 flags;
};
private static IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled) {
switch(msg) {
case 0x46://WM_WINDOWPOSCHANGING
if(Mouse.LeftButton != MouseButtonState.Pressed) {
WINDOWPOS wp = (WINDOWPOS)Marshal.PtrToStructure(lParam, typeof(WINDOWPOS));
wp.flags = wp.flags | 2; //SWP_NOMOVE
Marshal.StructureToPtr(wp, lParam, false);
}
break;
}
return IntPtr.Zero;
}
private void Window_Loaded(object sender, RoutedEventArgs e) {
HwndSource source = HwndSource.FromHwnd(new WindowInteropHelper(this).Handle);
source.AddHook(new HwndSourceHook(WndProc));
}
}
Handling WM_WINDOWPOSCHANGING this way will prevent any movement of the window unless left mouse button is pressed. This includes maximizing the window and programmatic change of window position as well, so you'll have to adapt the code if you need another behavior.