[CALC] Add theming support, requires Windows XP or later. CORE-13343

- Fix errors if a theme api is missing.
- Add callback to functions for drawing themed transparent background.
- Fix drawing glitch when theming is applied.
- Redraw on theme change: automatically redraw the window if the
  theme is changed while the application is active.
- Colours are now declared though RGB() macro.
- Removed safe DS_SHELLFONT declaration.

base/applications/calc/theme.c

@@ -0,0 +1,127 @@
+/*
+ * ReactOS Calc (Theming support)
+ *
+ * Copyright 2007-2017, Carlo Bramini
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include "calc.h"
+
+#define GET_CB(name) \
+    calc_##name = (type_##name)GetProcAddress(hUxTheme, #name); \
+    if (calc_##name == NULL) calc_##name = dummy_##name;
+
+static HTHEME WINAPI
+dummy_OpenThemeData(HWND hwnd, const WCHAR *pszClassList);
+
+static HRESULT WINAPI
+dummy_CloseThemeData(HTHEME hTheme);
+
+static HRESULT WINAPI
+dummy_DrawThemeBackground(HTHEME hTheme, HDC hdc, int iPartId, int iStateId,
+    const RECT *prc, const RECT *prcClip);
+
+static BOOL WINAPI
+dummy_IsAppThemed(void);
+
+static BOOL WINAPI
+dummy_IsThemeActive(void);
+
+static BOOL WINAPI
+dummy_IsThemeBackgroundPartiallyTransparent(HTHEME hTheme, int iPartId, int iStateId);
+
+static HRESULT WINAPI
+dummy_DrawThemeParentBackground(HWND hWnd, HDC hdc, RECT *prc);
+
+
+type_OpenThemeData       calc_OpenThemeData       = dummy_OpenThemeData;
+type_CloseThemeData      calc_CloseThemeData      = dummy_CloseThemeData;
+type_DrawThemeBackground calc_DrawThemeBackground = dummy_DrawThemeBackground;
+type_IsAppThemed         calc_IsAppThemed         = dummy_IsAppThemed;
+type_IsThemeActive       calc_IsThemeActive       = dummy_IsThemeActive;
+type_IsThemeBackgroundPartiallyTransparent calc_IsThemeBackgroundPartiallyTransparent = \
+    dummy_IsThemeBackgroundPartiallyTransparent;
+type_DrawThemeParentBackground calc_DrawThemeParentBackground = \
+    dummy_DrawThemeParentBackground;
+
+static HMODULE hUxTheme;
+
+static HTHEME WINAPI
+dummy_OpenThemeData(HWND hwnd, const WCHAR* pszClassList)
+{
+    return NULL;
+}
+
+static HRESULT WINAPI
+dummy_CloseThemeData(HTHEME hTheme)
+{
+    return E_NOTIMPL;
+}
+
+static HRESULT WINAPI
+dummy_DrawThemeBackground(HTHEME hTheme, HDC hdc, int iPartId, int iStateId,
+            const RECT* prc, const RECT* prcClip)
+{
+    return E_NOTIMPL;
+}
+
+static BOOL WINAPI
+dummy_IsAppThemed(void)
+{
+    return FALSE;
+}
+
+static BOOL WINAPI
+dummy_IsThemeActive(void)
+{
+    return FALSE;
+}
+
+static BOOL WINAPI
+dummy_IsThemeBackgroundPartiallyTransparent(HTHEME hTheme, int iPartId, int iStateId)
+{
+    return FALSE;
+}
+
+static HRESULT WINAPI
+dummy_DrawThemeParentBackground(HWND hWnd, HDC hdc, RECT *prc)
+{
+    return E_NOTIMPL;
+}
+
+void Theme_Start(HINSTANCE hInstance)
+{
+    hUxTheme = LoadLibrary(_T("UXTHEME"));
+    if (hUxTheme == NULL)
+        return;
+
+    GET_CB(OpenThemeData)
+    GET_CB(CloseThemeData)
+    GET_CB(DrawThemeBackground)
+    GET_CB(IsAppThemed)
+    GET_CB(IsThemeActive)
+    GET_CB(IsThemeBackgroundPartiallyTransparent)
+    GET_CB(DrawThemeParentBackground)
+}
+
+void Theme_Stop(void)
+{
+    if(hUxTheme == NULL)
+        return;
+
+    FreeLibrary(hUxTheme);
+    hUxTheme = NULL;
+}