Autohide Taskbar on Desktop Only

mods/autohide-taskbar-on-desktop.wh.cpp

@@ -0,0 +1,149 @@
+// ==WindhawkMod==
+// @id              autohide-taskbar-on-desktop
+// @name            autohide-taskbar-on-desktop
+// @version         1.0.1
+// @author          qwertyuiop00-art
+// @github          https://github.com/qwertyuiop00-art
+// @description     Hides taskbar on desktop, shows when an app is active.
+// @architecture    x86-64
+// @include         windhawk.exe
+// ==/WindhawkMod==
+
+// ==WindhawkModReadme==
+/*
+# Autohide Taskbar on Desktop 
+
+Automatically hides the taskbar when switching to the desktop, and restores it when any application is active/focused.
+*/
+// ==/WindhawkModReadme==
+
+#include <windows.h>
+#include <shellapi.h>
+#include <windhawk_api.h>
+
+static HANDLE g_thread = NULL;
+static DWORD g_threadId = 0;
+static HANDLE g_readyEvent = NULL;
+static int g_lastApplied = -1;
+
+void SetTaskbarAutoHide(bool enable) {
+    APPBARDATA abd = { sizeof(APPBARDATA) };
+    UINT state = (UINT)SHAppBarMessage(ABM_GETSTATE, &abd);
+
+    // Only flip the ABS_AUTOHIDE bit, leave others like ABS_ALWAYSONTOP alone
+    UINT newState = enable ? (state | ABS_AUTOHIDE) : (state & ~ABS_AUTOHIDE);
+
+    if (state != newState) {
+        abd.lParam = newState;
+        SHAppBarMessage(ABM_SETSTATE, &abd);
+        Wh_Log(L"> Taskbar state changed to: %d", enable);
+    }
+}
+
+void UpdateStateForWindow(HWND hwnd) {
+    if (!hwnd) hwnd = GetForegroundWindow();
+    if (!hwnd) return;
+
+    WCHAR className[256] = {0};
+    GetClassNameW(hwnd, className, ARRAYSIZE(className));
+
+    // Ignore shell flyouts and start menu to prevent visual flickering
+    if (wcscmp(className, L"Windows.UI.Core.CoreWindow") == 0 ||
+        wcscmp(className, L"XamlExplorerHostIslandWindow") == 0 ||
+        wcscmp(className, L"Shell_TrayWnd") == 0) {
+        return;
+    }
+
+    bool isDesktop = (wcscmp(className, L"Progman") == 0 || wcscmp(className, L"WorkerW") == 0);
+
+    // Only apply if the state has actually changed
+    if (g_lastApplied != (int)isDesktop) {
+        g_lastApplied = isDesktop;
+        SetTaskbarAutoHide(isDesktop);
+        Wh_Log(L"> Window switched. isDesktop=%d, class=%s", isDesktop, className);
+    }
+}
+
+void CALLBACK WinEventProc(HWINEVENTHOOK hWinEventHook, DWORD event, HWND hwnd, 
+                            LONG idObject, LONG idChild, DWORD dwEventThread, DWORD dwmsEventTime) {
+    // Filter to the specific window object as recommended
+    if (event != EVENT_SYSTEM_FOREGROUND || idObject != OBJID_WINDOW ||
+        idChild != CHILDID_SELF || !hwnd) {
+        return;
+    }
+    UpdateStateForWindow(hwnd);
+}
+
+DWORD WINAPI WinEventHookThread(LPVOID) {
+    MSG msg;
+    // Force message queue creation
+    PeekMessage(&msg, NULL, WM_USER, WM_USER, PM_NOREMOVE);
+
+    HWINEVENTHOOK hook = SetWinEventHook(EVENT_SYSTEM_FOREGROUND, EVENT_SYSTEM_FOREGROUND, 
+                                         NULL, WinEventProc, 0, 0, WINEVENT_OUTOFCONTEXT);
+
+    if (g_readyEvent) {
+        SetEvent(g_readyEvent);
+    }
+
+    UpdateStateForWindow(GetForegroundWindow());
+
+    while (GetMessage(&msg, NULL, 0, 0) > 0) {
+        TranslateMessage(&msg);
+        DispatchMessage(&msg);
+    }
+
+    if (hook) UnhookWinEvent(hook);
+    return 0;
+}
+
+BOOL WhTool_ModInit() {
+    Wh_Log(L"> WhTool_ModInit started");
+
+    // Lazily capture original state only once and persist it so it survives restarts
+    if (Wh_GetIntValue(L"OriginalStateSaved") != 1) {
+        APPBARDATA abd = { sizeof(APPBARDATA) };
+        UINT state = (UINT)SHAppBarMessage(ABM_GETSTATE, &abd);
+        Wh_SetIntValue(L"OriginalState", state);
+        Wh_SetIntValue(L"OriginalStateSaved", 1);
+    }
+
+    g_readyEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
+    if (!g_readyEvent) return FALSE;
+
+    g_thread = CreateThread(NULL, 0, WinEventHookThread, NULL, 0, &g_threadId);
+    if (!g_thread) {
+        CloseHandle(g_readyEvent);
+        return FALSE;
+    }
+
+    WaitForSingleObject(g_readyEvent, 3000);
+    CloseHandle(g_readyEvent);
+    g_readyEvent = NULL;
+
+    return TRUE;
+}
+
+void WhTool_ModUninit() {
+    Wh_Log(L"> WhTool_ModUninit started");
+
+    if (g_thread) {
+        // Safely close thread handling race conditions
+        while (!PostThreadMessage(g_threadId, WM_QUIT, 0, 0)) {
+            Sleep(10);
+        }
+        WaitForSingleObject(g_thread, INFINITE);
+        CloseHandle(g_thread);
+        g_thread = NULL;
+    }
+
+    // Restore user's original taskbar state cleanly
+    if (Wh_GetIntValue(L"OriginalStateSaved") == 1) {
+        UINT originalState = (UINT)Wh_GetIntValue(L"OriginalState");
+        APPBARDATA abd = { sizeof(APPBARDATA) };
+        abd.lParam = originalState;
+        SHAppBarMessage(ABM_SETSTATE, &abd);
+        // Clear saved state so next time we capture a fresh one
+        Wh_SetIntValue(L"OriginalStateSaved", 0);
+    }
+}