protected override void WinEventCallback(WinEventConstant eventType, IntPtr handle, int objectId, int childId)
{
// Only process events related to FG capture
if (eventType != WinEventConstant.EVENT_SYSTEM_FOREGROUND && eventType != WinEventConstant.EVENT_SYSTEM_MINIMIZEEND)
{
return;
}
// Only process events with valid parameters
if (handle == null || objectId != 0)
{
return;
}
// Get process ID
_ = NativeMethods.GetWindowThreadProcessId(handle, out uint windowThreadProcId);
// Ignore these windows
var windowStyle = NativeMethods.GetWindowStyleEx(handle);
if ((windowStyle & WindowStylesEx.WS_EX_NOACTIVATE) == WindowStylesEx.WS_EX_NOACTIVATE)
{
return;
}
// Ignore ghost window when target is unresponsive
// Ghost windows take foreground but target window doesn't trigger EVENT_SYSTEM_FOREGROUND
// when responsive again.
var className = NativeMethods.GetClassName(handle);
var currentTitle = NativeMethods.GetWindowText(handle);
if (className == "Ghost" && _lastTitle == currentTitle)
{
return;
}
// Get process path
string processName = NativeMethods.GetFullProcessName((int)windowThreadProcId);
// Send event
ForegroundWindowChanged?.Invoke(this, new ForegroundWindowChangedEventArgs
{
Handle = handle,
WindowThreadProcId = windowThreadProcId,
ProcessPath = processName
});
// Store title
_lastTitle = currentTitle;
}
protected override void WinEventCallback(WinEventConstant eventType, IntPtr handle, int objectId, int childId)
{
if (handle == _targetHandle && objectId == 0)
{
if (eventType == WinEventConstant.EVENT_OBJECT_DESTROY)
{
// Target window was closed
WindowClosed?.Invoke(this, EventArgs.Empty);
}
else if (eventType == WinEventConstant.EVENT_OBJECT_LOCATIONCHANGE)
{
// Target window size has changed
SendWindowDimensions(handle);
}
else if (eventType == WinEventConstant.EVENT_OBJECT_NAMECHANGE)
{
// Target window title has changed
SendWindowTitle(handle);
}
}
}
