Customly chromed Windows in wpf

Question

I've tried creating a customly chromed window in wpf using WindowStyle None, and AllowsTransparency True, however, when I maximize the window it covers the entire screen (and goes beond it's edges, it also hides the Windows-bar at the bottom of my screen, just like a game in fullscreen). How can I make the behaviour like a normal window, but with my own customly made wpf-chrome?

Answer 1

I found a solution, it required some win32 interop though. Not very pretty, but it works.

    protected override void OnSourceInitialized(EventArgs e)
    {
        base.OnSourceInitialized(e);

        IntPtr handle = (new WinInterop.WindowInteropHelper(this)).Handle;
        WinInterop.HwndSource.FromHwnd(handle).AddHook(new WinInterop.HwndSourceHook(WindowProc));
    }

    private IntPtr WindowProc(
        IntPtr hwnd,
        int msg,
        IntPtr wParam,
        IntPtr lParam,
        ref bool handled)
    {
        switch (msg)
        {
            case 0x0024:
                WmGetMinMaxInfo(hwnd, lParam);
                handled = true;
                break;
        }

        return (IntPtr)0;
    }

    private static void WmGetMinMaxInfo(IntPtr hwnd, IntPtr lParam)
    {
        MINMAXINFO mmi = (MINMAXINFO)Marshal.PtrToStructure(lParam, typeof(MINMAXINFO));

        // Adjust the maximized size and position to fit the work area of the correct monitor
        int MONITOR_DEFAULTTONEAREST = 0x00000002;
        IntPtr monitor = MonitorFromWindow(hwnd, MONITOR_DEFAULTTONEAREST);

        if (monitor != IntPtr.Zero)
        {
            MONITORINFO monitorInfo = new MONITORINFO();
            GetMonitorInfo(monitor, 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);
    }

    /// <summary>
    /// POINT aka POINTAPI
    /// </summary>
    [StructLayout(LayoutKind.Sequential)]
    public struct POINT
    {
        /// <summary>
        /// x coordinate of point.
        /// </summary>
        public int x;
        /// <summary>
        /// y coordinate of point.
        /// </summary>
        public int y;

        /// <summary>
        /// Construct a point of coordinates (x,y).
        /// </summary>
        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;
    };

    /// <summary>
    /// </summary>
    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
    public class MONITORINFO
    {
        /// <summary>
        /// </summary>            
        public int cbSize = Marshal.SizeOf(typeof(MONITORINFO));

        /// <summary>
        /// </summary>            
        public RECT rcMonitor = new RECT();

        /// <summary>
        /// </summary>            
        public RECT rcWork = new RECT();

        /// <summary>
        /// </summary>            
        public int dwFlags = 0;
    }

    /// <summary> Win32 </summary>
    [StructLayout(LayoutKind.Sequential, Pack = 0)]
    public struct RECT
    {
        /// <summary> Win32 </summary>
        public int left;
        /// <summary> Win32 </summary>
        public int top;
        /// <summary> Win32 </summary>
        public int right;
        /// <summary> Win32 </summary>
        public int bottom;

        /// <summary> Win32 </summary>
        public static readonly RECT Empty = new RECT();

        /// <summary> Win32 </summary>
        public int Width
        {
            get { return Math.Abs(right - left); }  // Abs needed for BIDI OS
        }
        /// <summary> Win32 </summary>
        public int Height
        {
            get { return bottom - top; }
        }

        /// <summary> Win32 </summary>
        public RECT(int left, int top, int right, int bottom)
        {
            this.left = left;
            this.top = top;
            this.right = right;
            this.bottom = bottom;
        }


        /// <summary> Win32 </summary>
        public RECT(RECT rcSrc)
        {
            this.left = rcSrc.left;
            this.top = rcSrc.top;
            this.right = rcSrc.right;
            this.bottom = rcSrc.bottom;
        }

        /// <summary> Win32 </summary>
        public bool IsEmpty
        {
            get
            {
                // BUGBUG : On Bidi OS (hebrew arabic) left > right
                return left >= right || top >= bottom;
            }
        }
        /// <summary> Return a user friendly representation of this struct </summary>
        public override string ToString()
        {
            if (this == RECT.Empty) { return "RECT {Empty}"; }
            return "RECT { left : " + left + " / top : " + top + " / right : " + right + " / bottom : " + bottom + " }";
        }

        /// <summary> Determine if 2 RECT are equal (deep compare) </summary>
        public override bool Equals(object obj)
        {
            if (!(obj is Rect)) { return false; }
            return (this == (RECT)obj);
        }

        /// <summary>Return the HashCode for this struct (not garanteed to be unique)</summary>
        public override int GetHashCode()
        {
            return left.GetHashCode() + top.GetHashCode() + right.GetHashCode() + bottom.GetHashCode();
        }


        /// <summary> Determine if 2 RECT are equal (deep compare)</summary>
        public static bool operator ==(RECT rect1, RECT rect2)
        {
            return (rect1.left == rect2.left && rect1.top == rect2.top && rect1.right == rect2.right && rect1.bottom == rect2.bottom);
        }

        /// <summary> Determine if 2 RECT are different(deep compare)</summary>
        public static bool operator !=(RECT rect1, RECT rect2)
        {
            return !(rect1 == rect2);
        }

    }

    [DllImport("user32")]
    internal static extern bool GetMonitorInfo(IntPtr hMonitor, MONITORINFO lpmi);

    /// <summary>
    /// 
    /// </summary>
    [DllImport("User32")]
    internal static extern IntPtr MonitorFromWindow(IntPtr handle, int flags);

Answer 2

It is the default property of the windows, when you maximize it will cover all the screen area including the Window Bar at the bottom. This is will happen only if you are setting WindoStyle to None (otherwise it will not cover the entire area). To avoid that pls use something like this in your maximize evnt so that you will get the actual work area.

Instead of setting the windowState= WindowStat.Maximized change the height and width of the window and change the image of the Maximize to Restore and viceversa.

window.Left=0;
window.Top=0;
window.Height=SystemParameters.WorkArea.Height;
window.Width=SystemParameters.WorkArea.Width;

Hopes this helps.

Answer 3

If you're not actually using the AllowsTransparency part, the WPF Shell Integration Library may work for you: http://code.msdn.com/WPFShell. The link on that page to the WPF SDK blog post describes what it's doing.