[reactos] 01/01: [USER32] Fix behavior of Task Switcher (Alt+Tab) (#1591)

[Katayama Hirofumi MZ]

https://git.reactos.org/?p=reactos.git;a=commitdiff;h=1010f3796ec4c76a8b8847...

commit 1010f3796ec4c76a8b88476319c52cba52907cef
Author:     Katayama Hirofumi MZ [e-mail]
AuthorDate: Fri May 31 17:02:47 2019 +0900
Commit:     GitHub [e-mail]
CommitDate: Fri May 31 17:02:47 2019 +0900

[USER32] Fix behavior of Task Switcher (Alt+Tab) (#1591)

Task Switcher didn't correctly behave on the windows with WS_EX_APPWINDOW extended style. CORE-15653
---
 win32ss/user/user32/controls/appswitch.c | 55 +++++++++++++++-----------------
 1 file changed, 25 insertions(+), 30 deletions(-)

diff --git a/win32ss/user/user32/controls/appswitch.c b/win32ss/user/user32/controls/appswitch.c
index ecd48b47e7..ee9c10677c 100644
--- a/win32ss/user/user32/controls/appswitch.c
+++ b/win32ss/user/user32/controls/appswitch.c
@@ -209,41 +209,36 @@ BOOL CALLBACK EnumerateCallback(HWND window, LPARAM lParam)
    return TRUE;
 }

-// Function mostly compatible with the normal EnumChildWindows,
-// except it lists in Z-Order and it doesn't ensure consistency
-// if a window is removed while enumerating
-void EnumWindowsZOrder(WNDENUMPROC callback, LPARAM lParam)
+static BOOL CALLBACK
+EnumWindowsProc(HWND hwnd, LPARAM lParam)
 {
-    HWND hwnd, hwndOwner;
+    HWND hwndOwner;
     WCHAR szClass[64];
     DWORD ExStyle;

-    for (hwnd = GetTopWindow(NULL); hwnd; hwnd = GetWindow(hwnd, GW_HWNDNEXT))
-    {
-        if (!IsWindowVisible(hwnd))
-            continue;
+    if (!IsWindowVisible(hwnd))
+        return TRUE;

-        // check special windows
-        if (!GetClassNameW(hwnd, szClass, _countof(szClass)) ||
-            wcscmp(szClass, L"Shell_TrayWnd") == 0 ||
-            wcscmp(szClass, L"Progman") == 0)
-        {
-            continue;
-        }
+    // check special windows
+    if (!GetClassNameW(hwnd, szClass, _countof(szClass)) ||
+        wcscmp(szClass, L"Shell_TrayWnd") == 0 ||
+        wcscmp(szClass, L"Progman") == 0)
+    {
+        return TRUE;
+    }

-        ExStyle = GetWindowLongPtrW(hwnd, GWL_EXSTYLE);
-        if (ExStyle & WS_EX_TOOLWINDOW)
-            continue;
+    ExStyle = GetWindowLongPtrW(hwnd, GWL_EXSTYLE);
+    if (ExStyle & WS_EX_TOOLWINDOW)
+        return TRUE;

-        hwndOwner = GetWindow(hwnd, GW_OWNER);
-        if ((ExStyle & WS_EX_APPWINDOW) || !IsWindowVisible(hwndOwner))
-        {
-            if (!callback(hwnd, lParam))
-                break;
-
-            continue;
-        }
+    hwndOwner = GetWindow(hwnd, GW_OWNER);
+    if (!IsWindowVisible(hwndOwner) || (ExStyle & WS_EX_APPWINDOW))
+    {
+        if (!EnumerateCallback(hwnd, lParam))
+            return FALSE;
     }
+
+    return TRUE;
 }

void ProcessMouseMessage(UINT message, LPARAM lParam)
@@ -428,8 +423,8 @@ BOOL ProcessHotKey(VOID)
 {
    if (!isOpen)
    {
-      windowCount=0;
-      EnumWindowsZOrder(EnumerateCallback, 0);
+      windowCount = 0;
+      EnumWindows(EnumWindowsProc, 0);

if (windowCount == 0)
          return FALSE;
@@ -574,7 +569,7 @@ LRESULT WINAPI DoAppSwitch( WPARAM wParam, LPARAM lParam )
       Esc = TRUE;

windowCount = 0;
-      EnumWindowsZOrder(EnumerateCallback, 0);
+      EnumWindows(EnumWindowsProc, 0);

if (windowCount < 2)
           return 0;