Fullscreen test

main.cpp

#include <windows.h>
#include <shobjidl.h>

void MarkFullscreen(HWND hWnd, bool fullscreen);

void
Fullscreen(HWND hWnd, bool removeFrame, bool fillScreen, bool less1Width, bool mark)
{
	if (removeFrame) {
		LONG_PTR style = GetWindowLong(hWnd, GWL_STYLE);
		SetWindowLongPtr(hWnd, GWL_STYLE, style & ~(WS_CAPTION | WS_THICKFRAME));
	}

	if (fillScreen) {
		/// Get monitor size
		HMONITOR hMon = MonitorFromWindow(hWnd, MONITOR_DEFAULTTONEAREST);

		MONITORINFO info = { 0 };
		info.cbSize = sizeof(info);
		GetMonitorInfo(hMon, &info);

		// Resize to fill the monitor
		RECT sr(info.rcMonitor);
		int width = sr.right - sr.left;
		int height = sr.bottom - sr.top;

		if (less1Width) width -= 1;
		SetWindowPos(hWnd, NULL,
			sr.left, sr.top,
			width, height,
			SWP_NOZORDER | SWP_NOACTIVATE | SWP_FRAMECHANGED);
	}

	if (mark) {
		MarkFullscreen(hWnd, true);
	}
}

void
Reset(HWND hWnd, RECT sr)
{
	LONG_PTR style = GetWindowLong(hWnd, GWL_STYLE);
	SetWindowLongPtr(hWnd, GWL_STYLE, style | WS_CAPTION | WS_THICKFRAME);

	int width = sr.right - sr.left;
	int height = sr.bottom - sr.top;
	SetWindowPos(hWnd, NULL,
		sr.left, sr.top,
		width, height,
		SWP_NOZORDER | SWP_NOACTIVATE | SWP_FRAMECHANGED);

	MarkFullscreen(hWnd, false);
}

void MarkFullscreen(HWND hWnd, bool fullscreen)
{
	// Mark as a fullscreen window to overlap the taskbar
	ITaskbarList *list = nullptr;
	ITaskbarList2 *list2 = nullptr;

	if (!SUCCEEDED(CoInitialize(0))) return;

	SUCCEEDED(
		CoCreateInstance(CLSID_TaskbarList, nullptr, CLSCTX_INPROC_SERVER, IID_ITaskbarList, (LPVOID*)&list)
	) && SUCCEEDED(
		list->HrInit()
	) && SUCCEEDED(
		list->QueryInterface(IID_ITaskbarList2, (LPVOID*)&list2)
	) && SUCCEEDED(
		list2->MarkFullscreenWindow(hWnd, fullscreen ? TRUE : FALSE)
	);

	if (list2) list2->Release();
	if (list) list->Release();
	CoUninitialize();
}

HBRUSH g_red = NULL;
HINSTANCE g_hInstance = NULL;

LRESULT CALLBACK
WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
	static bool extendClientArea = false;
	static RECT savedPos = { 0 };

	static HWND hRemoveFrame = NULL;
	static HWND hFillScreen = NULL;
	static HWND hLess1Button = NULL;
	static HWND hMark = NULL;
	static HWND hExtendClientArea = NULL;
	static HWND hGoButton = NULL;
	static HWND hResetButton = NULL;

	const int removeFrame = 1;
	const int fillScreen = 2;
	const int less1Button = 3;
	const int markButton = 4;
	const int ECAButton = 5;
	const int goButton = 6;
	const int resetButton = 7;

	switch (msg)
	{
		case WM_CREATE:
		{
			const DWORD buttonStyle = WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON;
			const DWORD checkStyle = WS_VISIBLE | WS_CHILD | BS_AUTOCHECKBOX;
			hRemoveFrame = CreateWindow("BUTTON", "Remove Frame", checkStyle, 15, 15, 150, 25, hWnd, (HMENU)removeFrame, g_hInstance, NULL);
			hFillScreen = CreateWindow("BUTTON", "Fill Screen", checkStyle, 15, 45, 150, 25, hWnd, (HMENU)fillScreen, g_hInstance, NULL);
			hLess1Button = CreateWindow("BUTTON", "Width - 1", checkStyle, 40, 75, 125, 25, hWnd, (HMENU)less1Button, g_hInstance, NULL);
			hMark = CreateWindow("BUTTON", "Mark Fullscreen", checkStyle, 15, 105, 150, 25, hWnd, (HMENU)markButton, g_hInstance, NULL);
			hExtendClientArea = CreateWindow("BUTTON", "Extend Client Area", checkStyle, 15, 135, 150, 25, hWnd, (HMENU)ECAButton, g_hInstance, NULL);
			hGoButton = CreateWindow("BUTTON", "Go", buttonStyle, 15, 165, 150, 25, hWnd, (HMENU)goButton, g_hInstance, NULL);
			hResetButton = CreateWindow("BUTTON", "Reset", buttonStyle, 15, 195, 150, 25, hWnd, (HMENU)resetButton, g_hInstance, NULL);
			CheckDlgButton(hWnd, removeFrame, BST_CHECKED);
			CheckDlgButton(hWnd, fillScreen, BST_CHECKED);
			CheckDlgButton(hWnd, less1Button, BST_UNCHECKED);
			CheckDlgButton(hWnd, markButton, BST_CHECKED);
			CheckDlgButton(hWnd, ECAButton, BST_UNCHECKED);

			GetWindowRect(hWnd, &savedPos);
			break;
		}

		case WM_NCCALCSIZE:
			if (extendClientArea) {
				return 0L;
			}
			else {
				break;
			}

		case WM_COMMAND:
			if (LOWORD(wParam) == goButton && HIWORD(wParam) == BN_CLICKED) {
				Fullscreen(hWnd,
					IsDlgButtonChecked(hWnd, removeFrame) == BST_CHECKED,
					IsDlgButtonChecked(hWnd, fillScreen) == BST_CHECKED,
					IsDlgButtonChecked(hWnd, less1Button) == BST_CHECKED,
					IsDlgButtonChecked(hWnd, markButton) == BST_CHECKED);
				return 0L;
			} else if (LOWORD(wParam) == resetButton && HIWORD(wParam) == BN_CLICKED) {
				Reset(hWnd, savedPos);
				extendClientArea = false;
				CheckDlgButton(hWnd, ECAButton, BST_UNCHECKED);
				SetWindowPos(hWnd, NULL, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE | SWP_NOZORDER | SWP_NOACTIVATE | SWP_FRAMECHANGED);
				return 0L;
			}
			else if (LOWORD(wParam) == ECAButton) {
				bool newValue = extendClientArea;
				if (HIWORD(wParam) == BN_CLICKED) {
					extendClientArea = IsDlgButtonChecked(hWnd, ECAButton) == BST_CHECKED;
				}
				if (newValue != extendClientArea) {
					SetWindowPos(hWnd, NULL, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE | SWP_NOZORDER | SWP_NOACTIVATE | SWP_FRAMECHANGED);
				}
			}
			break;

		case WM_PAINT:
		{
			// Outline the window in red
			PAINTSTRUCT ps;
			HDC hdc = BeginPaint(hWnd, &ps);
			RECT r;
			GetClientRect(hWnd, &r);
			FillRect(hdc, &r, g_red);
			r.top += 10; r.left += 10;  r.right -= 10; r.bottom -= 10;
			FillRect(hdc, &r, (HBRUSH)COLOR_WINDOW);
			EndPaint(hWnd, &ps);
			return 0L;
		}

		case WM_SIZE:
			RedrawWindow(hWnd, NULL, NULL, RDW_INVALIDATE | RDW_INTERNALPAINT);
			break;

		case WM_CLOSE:
			PostQuitMessage(0);
			return 0L;

		default:
			break;
	}

	return DefWindowProc(hWnd, msg, wParam, lParam);
}

int CALLBACK
WinMain(HINSTANCE hInstance, HINSTANCE, LPSTR, int)
{
	g_red = CreateSolidBrush(RGB(255, 0, 0));
	g_hInstance = hInstance;

	WNDCLASS wc = { 0 };
	wc.lpfnWndProc = WndProc;
	wc.hInstance = hInstance;
	wc.hbrBackground = (HBRUSH)COLOR_BACKGROUND;
	wc.hCursor = (HCURSOR)LoadCursor(NULL, IDC_ARROW);
	wc.lpszClassName = "Fullscreen Test";

	RegisterClass(&wc);

	HWND hWnd = CreateWindow(
		wc.lpszClassName,
		"Fullscreen Test",
		WS_OVERLAPPEDWINDOW | WS_CLIPCHILDREN | WS_VISIBLE,
		0, 0, 250, 300,
		NULL, NULL,
		hInstance,
		NULL);

	MSG msg;
	while (GetMessage(&msg, NULL, 0, 0) > 0) {
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}

	return 0;
}