matplotlib · QuLogic · Jan 11, 2019 · Jan 1, 2019
diff --git a/lib/matplotlib/backends/_backend_tk.py b/lib/matplotlib/backends/_backend_tk.py
@@ -23,20 +23,20 @@
 from matplotlib.widgets import SubplotTool
 
 try:
-    from matplotlib._windowing import GetForegroundWindow, SetForegroundWindow
+    from ._tkagg import Win32_GetForegroundWindow, Win32_SetForegroundWindow
 except ImportError:
     @contextmanager
     def _restore_foreground_window_at_end():
         yield
 else:
     @contextmanager
     def _restore_foreground_window_at_end():
-        foreground = GetForegroundWindow()
+        foreground = Win32_GetForegroundWindow()
         try:
             yield
         finally:
             if rcParams['tk.window_focus']:
-                SetForegroundWindow(foreground)
+                Win32_SetForegroundWindow(foreground)
 
 
 _log = logging.getLogger(__name__)

diff --git a/lib/matplotlib/backends/windowing.py b/lib/matplotlib/backends/windowing.py
@@ -16,7 +16,9 @@
 try:
     if not rcParams['tk.window_focus']:
         raise ImportError
-    from matplotlib._windowing import GetForegroundWindow, SetForegroundWindow
+    from matplotlib.backends._tkagg import (
+        Win32_GetForegroundWindow as GetForegroundWindow,
+        Win32_SetForegroundWindow as SetForegroundWindow)
 
 except ImportError:
 

diff --git a/setup.cfg.template b/setup.cfg.template
@@ -41,8 +41,6 @@
 #
 # - Tk support requires Tk development headers and Tkinter.
 # - Mac OSX backend requires the Cocoa headers included with XCode.
-# - Windowing is MS-Windows specific, and requires the "windows.h"
-#   header.
 #
 # The other GUI toolkits do not require any extension code, and can be
 # used as long as the libraries are installed on your system --
@@ -61,7 +59,6 @@
 #agg = auto
 #macosx = auto
 #tkagg = auto
-#windowing = auto
 
 [rc_options]
 # User-configurable options

diff --git a/setup.py b/setup.py
@@ -69,7 +69,6 @@
     setupext.BackendAgg(),
     setupext.BackendTkAgg(),
     setupext.BackendMacOSX(),
-    setupext.Windowing(),
     'Optional package data',
     setupext.Dlls(),
     ]

diff --git a/setupext.py b/setupext.py
@@ -1162,8 +1162,10 @@ def get_extension(self):
     def add_flags(self, ext):
         ext.include_dirs.insert(0, 'src')
         if sys.platform == 'win32':
-            # PSAPI library needed for finding Tcl/Tk at run time
-            ext.libraries.extend(['psapi'])
+            # psapi library needed for finding Tcl/Tk at run time.
+            # user32 library needed for window manipulation functions.
+            ext.libraries.extend(['psapi', 'user32'])
+            ext.extra_link_args.extend(["-mwindows"])
         elif sys.platform == 'linux':
             ext.libraries.extend(['dl'])
 
@@ -1189,32 +1191,6 @@ def get_extension(self):
         return ext
 
 
-class Windowing(OptionalBackendPackage):
-    """
-    Builds the windowing extension.
-    """
-    name = "windowing"
-
-    def check_requirements(self):
-        if sys.platform != 'win32':
-            raise CheckFailed("Microsoft Windows only")
-        config = self.get_config()
-        if config is False:
-            raise CheckFailed("skipping due to configuration")
-        return ""
-
-    def get_extension(self):
-        sources = [
-            "src/_windowing.cpp"
-            ]
-        ext = make_extension('matplotlib._windowing', sources)
-        ext.include_dirs.extend(['C:/include'])
-        ext.libraries.extend(['user32'])
-        ext.library_dirs.extend(['C:/lib'])
-        ext.extra_link_args.append("-mwindows")
-        return ext
-
-
 class OptionalPackageData(OptionalPackage):
     config_category = "package_data"
 

diff --git a/src/_tkagg.cpp b/src/_tkagg.cpp
@@ -15,6 +15,10 @@
 
 #include <agg_basics.h> // agg:int8u
 
+#ifdef _WIN32
+#include <windows.h>
+#endif
+
 // Include our own excerpts from the Tcl / Tk headers
 #include "_tkmini.h"
 
@@ -245,15 +249,45 @@ static PyObject *mpl_tk_blit(PyObject *self, PyObject *args)
     }
 }
 
+#ifdef _WIN32
+static PyObject *
+Win32_GetForegroundWindow(PyObject *module, PyObject *args)
+{
+    HWND handle = GetForegroundWindow();
+    if (!PyArg_ParseTuple(args, ":GetForegroundWindow")) {
+        return NULL;
+    }
+    return PyLong_FromSize_t((size_t)handle);
+}
+
+static PyObject *
+Win32_SetForegroundWindow(PyObject *module, PyObject *args)
+{
+    HWND handle;
+    if (!PyArg_ParseTuple(args, "n:SetForegroundWindow", &handle)) {
+        return NULL;
+    }
+    if (!SetForegroundWindow(handle)) {
+        return PyErr_Format(PyExc_RuntimeError, "Error setting window");
+    }
+    Py_INCREF(Py_None);
+    return Py_None;
+}
+#endif
+
 static PyMethodDef functions[] = {
     /* Tkinter interface stuff */
-    { "tkinit", (PyCFunction)_tkinit, 1 },
-    { "blit", (PyCFunction)mpl_tk_blit, 1 },
+    { "tkinit", (PyCFunction)_tkinit, METH_VARARGS },
+    { "blit", (PyCFunction)mpl_tk_blit, METH_VARARGS },
+#ifdef _WIN32
+    { "Win32_GetForegroundWindow", (PyCFunction)Win32_GetForegroundWindow, METH_VARARGS },
+    { "Win32_SetForegroundWindow", (PyCFunction)Win32_SetForegroundWindow, METH_VARARGS },
+#endif
     { NULL, NULL } /* sentinel */
 };
 
 // Functions to fill global TCL / Tk function pointers by dynamic loading
-#if defined(_WIN32) || defined(__WIN32__) || defined(WIN32)
+#ifdef _WIN32
 
 /*
  * On Windows, we can't load the tkinter module to get the TCL or Tk symbols,
@@ -262,7 +296,6 @@ static PyMethodDef functions[] = {
  * Python, we scan all modules in the running process for the TCL and Tk
  * function names.
  */
-#include <windows.h>
 #define PSAPI_VERSION 1
 #include <psapi.h>
 // Must be linked with 'psapi' library

diff --git a/src/_windowing.cpp b/src/_windowing.cpp