Added window methods to request and to check focus

Signed-off-by: Stefan Schindler <stefan@boxbox.org>
Signed-off-by: Jan Haller <bromeon@gmail.com>

include/SFML/Window/Window.hpp

@@ -403,6 +403,7 @@ public:
     /// on the previous thread first if it was active.
     /// Only one window can be active on a thread at a time, thus
     /// the window previously active (if any) automatically gets deactivated.
+    /// This is not to be confused with requestFocus().
     ///
     /// \param active True to activate, false to deactivate
     ///
@@ -411,6 +412,37 @@ public:
     ////////////////////////////////////////////////////////////
     bool setActive(bool active = true) const;
 
+    ////////////////////////////////////////////////////////////
+    /// \brief Request the current window to be made the active
+    ///        foreground window
+    ///
+    /// At any given time, only one window may have the input focus
+    /// to receive input events such as keystrokes or mouse
+    /// events.
+    /// If a window requests focus, it only hints to the operating
+    /// system, that it would like to be focused. The operating system
+    /// is free to deny the request. For example under Windows OS
+    /// windows are not allowed to steal focus. But the user
+    /// will be notified through a flashing taskbar button.
+    /// This is not to be confused with setActive().
+    ///
+    /// \return True if operation was successful, false otherwise
+    ///
+    ////////////////////////////////////////////////////////////
+    bool requestFocus();
+
+    ////////////////////////////////////////////////////////////
+    /// \brief Determine whether the window has the input focus
+    ///
+    /// At any given time, only one window may have the input focus
+    /// to receive input events such as keystrokes or most mouse
+    /// events.
+    ///
+    /// \return True if window has focus, false otherwise
+    ///
+    ////////////////////////////////////////////////////////////
+    bool hasFocus() const;
+
     ////////////////////////////////////////////////////////////
     /// \brief Display on screen what has been rendered to the window so far
     ///

src/SFML/Window/OSX/WindowImplCocoa.hpp

@@ -320,6 +320,23 @@ public:
     ////////////////////////////////////////////////////////////
     virtual void setKeyRepeatEnabled(bool enabled);
 
+    ////////////////////////////////////////////////////////////
+    /// \brief Request the current window to be made the active
+    ///        foreground window
+    ///
+    /// \return True if operation was successful, false otherwise
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual bool requestFocus();
+
+    ////////////////////////////////////////////////////////////
+    /// \brief Determine whether the window has the input focus
+    ///
+    /// \return True if window has focus, false otherwise
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual bool hasFocus() const;
+
 protected:
 
     ////////////////////////////////////////////////////////////

src/SFML/Window/OSX/WindowImplCocoa.mm

@@ -552,6 +552,20 @@ void WindowImplCocoa::setKeyRepeatEnabled(bool enabled)
 }
 
 
+////////////////////////////////////////////////////////////
+bool WindowImplCocoa::requestFocus()
+{
+    return [m_delegate requestFocus];
+}
+
+
+////////////////////////////////////////////////////////////
+bool WindowImplCocoa::hasFocus() const
+{
+    return [m_delegate hasFocus];
+}
+
+
 } // namespace priv
 
 } // namespace sf

src/SFML/Window/Unix/WindowImplX11.cpp

@@ -483,6 +483,26 @@ void WindowImplX11::setKeyRepeatEnabled(bool enabled)
 }
 
 
+////////////////////////////////////////////////////////////
+bool WindowImplX11::requestFocus()
+{
+    XRaiseWindow(m_display, m_window);
+    XSetInputFocus(m_display, m_window, RevertToPointerRoot, CurrentTime);
+    return true;
+}
+
+
+////////////////////////////////////////////////////////////
+bool WindowImplX11::hasFocus() const
+{
+    ::Window focusedWindow = 0;
+    int revertToReturn = 0;
+    XGetInputFocus(m_display, &focusedWindow, &revertToReturn);
+
+    return m_window == focusedWindow;
+}
+
+
 ////////////////////////////////////////////////////////////
 void WindowImplX11::switchToFullscreen(const VideoMode& mode)
 {

src/SFML/Window/Unix/WindowImplX11.hpp

@@ -154,6 +154,23 @@ public:
     ////////////////////////////////////////////////////////////
     virtual void setKeyRepeatEnabled(bool enabled);
 
+    ////////////////////////////////////////////////////////////
+    /// \brief Request the current window to be made the active
+    ///        foreground window
+    ///
+    /// \return True if operation was successful, false otherwise
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual bool requestFocus();
+
+    ////////////////////////////////////////////////////////////
+    /// \brief Determine whether the window has the input focus
+    ///
+    /// \return True if window has focus, false otherwise
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual bool hasFocus() const;
+
 protected:
 
     ////////////////////////////////////////////////////////////

src/SFML/Window/Win32/WindowImplWin32.cpp

@@ -366,6 +366,20 @@ void WindowImplWin32::setKeyRepeatEnabled(bool enabled)
 }
 
 
+////////////////////////////////////////////////////////////
+bool WindowImplWin32::requestFocus()
+{
+    return SetForegroundWindow(m_handle);
+}
+
+
+////////////////////////////////////////////////////////////
+bool WindowImplWin32::hasFocus() const
+{
+    return m_handle == GetForegroundWindow();
+}
+
+
 ////////////////////////////////////////////////////////////
 void WindowImplWin32::registerWindowClass()
 {

src/SFML/Window/Win32/WindowImplWin32.hpp

@@ -153,6 +153,23 @@ public:
     ////////////////////////////////////////////////////////////
     virtual void setKeyRepeatEnabled(bool enabled);
 
+    ////////////////////////////////////////////////////////////
+    /// \brief Request the current window to be made the active
+    ///        foreground window
+    ///
+    /// \return True if operation was successful, false otherwise
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual bool requestFocus();
+
+    ////////////////////////////////////////////////////////////
+    /// \brief Determine whether the window has the input focus
+    ///
+    /// \return True if window has focus, false otherwise
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual bool hasFocus() const;
+
 protected:
 
     ////////////////////////////////////////////////////////////

src/SFML/Window/Window.cpp

@@ -337,6 +337,25 @@ bool Window::setActive(bool active) const
 
 
 ////////////////////////////////////////////////////////////
+bool Window::requestFocus()
+{
+    if (m_impl)
+        return m_impl->requestFocus();
+    return false;
+}
+
+
+////////////////////////////////////////////////////////////
+bool Window::hasFocus() const
+{
+    if (m_impl)
+        return m_impl->hasFocus();
+    return false;
+}
+
+
+////////////////////////////////////////////////////////////
+
 void Window::display()
 {
     // Display the backbuffer on screen

src/SFML/Window/WindowImpl.hpp

@@ -194,6 +194,23 @@ public:
     ////////////////////////////////////////////////////////////
     virtual void setKeyRepeatEnabled(bool enabled) = 0;
 
+    ////////////////////////////////////////////////////////////
+    /// \brief Request the current window to be made the active
+    ///        foreground window
+    ///
+    /// \return True if operation was successful, false otherwise
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual bool requestFocus() = 0;
+
+    ////////////////////////////////////////////////////////////
+    /// \brief Determine whether the window has the input focus
+    ///
+    /// \return True if window has focus, false otherwise
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual bool hasFocus() const = 0;
+
 protected:
 
     ////////////////////////////////////////////////////////////