private IntPtr WindowProc(IntPtr hwnd, Win32MessageType uMsg, IntPtr wParam, IntPtr lParam)
{
if (HandleWindowEvent(hwnd, uMsg, wParam, lParam))
{
return(IntPtr.Zero);
}
if (uMsg == Win32MessageType.WM_SETCURSOR)
{
uint lParam32 = (uint)lParam.ToInt64();
var hitTest = (Win32HitTestResult)(lParam32 & 0xFFFF);
if (hitTest == Win32HitTestResult.HTCLIENT)
{
IntPtr cursor = Win32API.LoadImageW(
IntPtr.Zero,
Win32SystemResources.IDC_ARROW,
Win32ImageType.IMAGE_CURSOR,
0, 0,
Win32LoadImageFlags.LR_DEFAULTSIZE | Win32LoadImageFlags.LR_SHARED
);
if (cursor != IntPtr.Zero)
{
Win32API.SetCursor(cursor);
return(IntPtr.Zero);
}
}
}
if (uMsg == Win32MessageType.WM_DESTROY)
{
windows.Remove(hwnd);
Win32API.PostQuitMessage(0);
return(IntPtr.Zero);
}
if (uMsg == Win32MessageType.WM_MOUSEMOVE)
{
if (windows.TryGetValue(hwnd, out var window))
{
uint wParam32 = (uint)wParam.ToInt64();
uint lParam32 = (uint)lParam.ToInt64();
int x = (short)(lParam32 & 0xFFFF);
int y = (short)((lParam32 >> 16) & 0xFFFF);
window.StartupInfo.OnMouseMove(new Point(x, y));
}
return(IntPtr.Zero);
}
if (uMsg == Win32MessageType.WM_CHAR)
{
if (windows.TryGetValue(hwnd, out var window))
{
char c = (char)wParam.ToInt64();
if (!char.IsControl(c))
{
window.StartupInfo.OnTextInput(c.ToString());
}
}
return(IntPtr.Zero);
}
if (uMsg == Win32MessageType.WM_PAINT)
{
PAINTSTRUCT ps = new PAINTSTRUCT();
IntPtr hdc = Win32API.BeginPaint(hwnd, ref ps);
try
{
if (windows.TryGetValue(hwnd, out var window))
{
Rectangle area = new Rectangle(ps.rcPaint.left, ps.rcPaint.top, ps.rcPaint.Width, ps.rcPaint.Height);
using (Win32Bitmap bitmap = Win32Bitmap.Create(hdc, area.Width, area.Height))
{
using (Win32Canvas canvas = graphics.CreateCanvas(bitmap, new Point(-area.X, -area.Y)))
{
window.StartupInfo.OnPaint(canvas, area);
}
bitmap.CopyTo(hdc, area.X, area.Y);
}
}
}
finally
{
Win32API.EndPaint(hwnd, ref ps);
}
return(IntPtr.Zero);
}
if (uMsg == Win32MessageType.WM_SIZE)
{
if (windows.TryGetValue(hwnd, out var window))
{
ulong lParam32 = (uint)lParam.ToInt64();
int width = (short)(lParam32 & 0xFFFF);
int height = (short)((lParam32 >> 16) & 0xFFFF);
window.StartupInfo.OnResize(new Size(width, height));
}
return(IntPtr.Zero);
}
return(Win32API.DefWindowProcW(hwnd, uMsg, wParam, lParam));
}
public void Run(INativeWindowStartupInfo startupInfo)
{
GdiplusStartupInput gdiPlusStartupInput = GdiplusStartupInput.CreateV1();
GdiPlusAPI.CheckStatus(GdiPlusAPI.GdiplusStartup(out var gdiPlusToken, ref gdiPlusStartupInput, out _));
IntPtr hInstance = Win32API.GetModuleHandleW(null);
var windowClass = new WNDCLASSEXW();
windowClass.cbSize = (uint)Marshal.SizeOf <WNDCLASSEXW>();
windowClass.lpfnWndProc = WindowProc;
windowClass.hInstance = hInstance;
windowClass.lpszClassName = WindowClassName;
var atom = Win32API.RegisterClassExW(ref windowClass);
if (atom == 0)
{
throw new InvalidOperationException("Failed to register window class.");
}
try
{
const int CW_USEDEFAULT = unchecked ((int)0x80000000);
IntPtr hwnd = Win32API.CreateWindowExW(
0,
WindowClassName,
startupInfo.Title,
Win32WindowStyle.WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT, CW_USEDEFAULT,
startupInfo.Width, startupInfo.Height,
IntPtr.Zero,
IntPtr.Zero,
hInstance,
IntPtr.Zero
);
if (hwnd == IntPtr.Zero)
{
throw new InvalidOperationException("Failed to create a window.");
}
var window = new Win32Window(hwnd, startupInfo);
windows.Add(hwnd, window);
startupInfo.OnCreate(window);
try
{
Win32API.ShowWindow(hwnd, Win32ShowWindowCommand.SW_SHOWNORMAL);
MSG msg = new MSG();
int mRet;
while ((mRet = Win32API.GetMessageW(ref msg, IntPtr.Zero, 0, 0)) != 0)
{
if (mRet == -1)
{
throw new InvalidOperationException("Failed to retrieve a message.");
}
Win32API.TranslateMessage(ref msg);
Win32API.DispatchMessageW(ref msg);
}
}
finally
{
// usually window will be destroyed before this point, unless error occurs
if (Win32API.DestroyWindow(hwnd) == 0)
{
// todo: log warning ?
}
}
}
finally
{
if (Win32API.UnregisterClassW(WindowClassName, hInstance) == 0)
{
// todo: log warning
}
// todo: use separate finally for GDI+
GdiPlusAPI.GdiplusShutdown(gdiPlusToken);
}
}
public void SetTitle(string title)
{
Win32API.SetWindowTextW(windowHandle, title);
}