diff --git a/gltools/@include/glfwLib.pxd b/gltools/@include/glfwLib.pxd
index 388b3e7..1696054 100644
--- a/gltools/@include/glfwLib.pxd
+++ b/gltools/@include/glfwLib.pxd
@@ -271,7 +271,7 @@ cdef extern from "GLFW/glfw3.h":
     ctypedef void (* GLFWcursorposfun)(GLFWwindow *,double,double)
     ctypedef void (* GLFWcursorenterfun)(GLFWwindow *,int)
     ctypedef void (* GLFWscrollfun)(GLFWwindow *,double,double)
-    ctypedef void (* GLFWkeyfun)(GLFWwindow *,int,int)
+    ctypedef void (* GLFWkeyfun)(GLFWwindow *,int,int,int,int)
     ctypedef void (* GLFWcharfun)(GLFWwindow *,int)
     ctypedef void (* GLFWmonitorfun)(c_GLFWmonitor,int)
     
diff --git a/gltools/@src/GLFW.pxi b/gltools/@src/GLFW.pxi
index aa0dfb1..b0cb864 100644
--- a/gltools/@src/GLFW.pxi
+++ b/gltools/@src/GLFW.pxi
@@ -280,8 +280,8 @@ cdef class Window:
         Callback on mouse button press or release
         '''
         pass
-    
-    cpdef onKey(self, int key, int action):
+
+    cpdef onKey(self, int key, int scancode, int action, int mods):
         '''
         Callback on key press or relase.
         '''
@@ -355,11 +355,11 @@ cdef void cb_onMouseButton(GLFWwindow *window, int button, int action):
     except Exception as err:
         self.error = err
 
-cdef void cb_onKey(GLFWwindow *window, int key, int action):
+cdef void cb_onKey(GLFWwindow *window, int key, int scancode, int action, int mods):
     cdef Window self = <Window>glfwGetWindowUserPointer(window)
     
     try:
-        self.onKey(key, action)
+        self.onKey(key, scancode, action, mods)
     except Exception as err:
         self.error = err
 
diff --git a/gltools/gltools.pxd b/gltools/gltools.pxd
index 6afdb20..f4bd64b 100644
--- a/gltools/gltools.pxd
+++ b/gltools/gltools.pxd
@@ -77,7 +77,7 @@ cdef class Window:
     cpdef onRefresh(self)
     cpdef onCursorPos(self, double x, double y)
     cpdef onMouseButton(self, int button, int action)
-    cpdef onKey(self, int key, int action)
+    cpdef onKey(self, int key, int scancode, int action, int mods)
     cpdef onChar(self, ch)
     cpdef onFocus(self, int status)
     cpdef onEnter(self, int status)
diff --git a/gltools/test.py b/gltools/test.py
index e5f8b6c..8080b51 100644
--- a/gltools/test.py
+++ b/gltools/test.py
@@ -306,7 +306,7 @@ class MainWindow(gl.Window):
         
         self.onRefresh()
     
-    def onKey(self, key, action):
+    def onKey(self, key, scancode, action, mods):
         #print('onKey ', key, action)
         if key == gl.KEY.ESCAPE:
             self.running = False