Window does not resize properly when moved to larger display

Question

My WPF application is exhibiting strange behavior on my two monitor laptop development system. The second monitor has a resolution of 1920 x 1080; the laptop\'s resolution is 1

Answer 1

Turns out its not a complicated fix. The MinTrackSize point (bounds) needs to be set to the working area dimensions of the secondary monitor.

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

    /*  0x0001        // center rect to monitor 
        0x0000        // clip rect to monitor 
        0x0002        // use monitor work area 
        0x0000        // use monitor entire area */

    int MONITOR_DEFAULTTONEAREST = 0x00000002;
    System.IntPtr monitor = MonitorFromWindow(hwnd, MONITOR_DEFAULTTONEAREST);

    if (monitor != System.IntPtr.Zero)
    {
        MONITORINFO monitorInfo = new MONITORINFO();
        GetMonitorInfo(monitor, monitorInfo);
        RECT rcWorkArea = monitorInfo.rcWork;
        RECT rcMonitorArea = monitorInfo.rcMonitor;

        // set the maximize size of the application
        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);

        // reset the bounds of the application to the monitor working dimensions
        mmi.ptMaxTrackSize.x = mmi.ptMaxSize.x;
        mmi.ptMaxTrackSize.y = mmi.ptMaxSize.y;
    }

    System.Runtime.InteropServices.Marshal.StructureToPtr(mmi, lParam, true);
}

[System.Runtime.InteropServices.StructLayout(System.Runtime.InteropServices.LayoutKind.Sequential)]
public struct MINMAXINFO
{
    public POINT ptReserved;
    public POINT ptMaxSize;
    public POINT ptMaxPosition;
    public POINT ptMinTrackSize;
    public POINT ptMaxTrackSize;
};