Merge branch 'feature/window_focus'

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 +412,35 @@ 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.
+    /// This is not to be confused with setActive().
+    ///
+    /// \see hasFocus
+    ///
+    ////////////////////////////////////////////////////////////
+    void requestFocus();
+
+    ////////////////////////////////////////////////////////////
+    /// \brief Check 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
+    /// \see requestFocus
+    ///
+    ////////////////////////////////////////////////////////////
+    bool hasFocus() const;
+
     ////////////////////////////////////////////////////////////
     /// \brief Display on screen what has been rendered to the window so far
     ///

src/SFML/Window/Android/WindowImplAndroid.cpp

@@ -181,6 +181,21 @@ void WindowImplAndroid::setKeyRepeatEnabled(bool enabled)
 }
 
 
+////////////////////////////////////////////////////////////
+void WindowImplAndroid::requestFocus()
+{
+    // Not applicable
+}
+
+
+////////////////////////////////////////////////////////////
+bool WindowImplAndroid::hasFocus() const
+{
+    // Not applicable
+    return false;
+}
+
+
 ////////////////////////////////////////////////////////////
 void WindowImplAndroid::forwardEvent(const Event& event)
 {

src/SFML/Window/Android/WindowImplAndroid.hpp

@@ -154,6 +154,21 @@ public:
     ////////////////////////////////////////////////////////////
     virtual void setKeyRepeatEnabled(bool enabled);
 
+    ////////////////////////////////////////////////////////////
+    /// \brief Request the current window to be made the active
+    ///        foreground window
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual void requestFocus();
+
+    ////////////////////////////////////////////////////////////
+    /// \brief Check whether the window has the input focus
+    ///
+    /// \return True if window has focus, false otherwise
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual bool hasFocus() const;
+
     static void forwardEvent(const Event& event);
     static WindowImplAndroid* singleInstance;
 

src/SFML/Window/OSX/SFViewController.mm

@@ -187,6 +187,26 @@
 }
 
 
+////////////////////////////////////////////////////////
+-(void)requestFocus
+{
+    // Note: this doesn't imply that the view will get any event.
+    // The user has to make sure events are forwarded to the view
+    // with the usual responder chain.
+    [[m_view window] makeKeyAndOrderFront:nil];
+
+    // In case the app is not active, make its dock icon bounce for one sec
+    [NSApp requestUserAttention:NSInformationalRequest];
+}
+
+
+////////////////////////////////////////////////////////////
+-(BOOL)hasFocus
+{
+    return [NSApp keyWindow] == [m_view window];
+}
+
+
 ////////////////////////////////////////////////////////
 -(void)enableKeyRepeat
 {

src/SFML/Window/OSX/SFWindowController.mm

@@ -451,6 +451,23 @@
 }
 
 
+////////////////////////////////////////////////////////
+-(void)requestFocus
+{
+    [m_window makeKeyAndOrderFront:nil];
+
+    // In case the app is not active, make its dock icon bounce for one sec
+    [NSApp requestUserAttention:NSInformationalRequest];
+}
+
+
+////////////////////////////////////////////////////////////
+-(BOOL)hasFocus
+{
+    return [NSApp keyWindow] == m_window;
+}
+
+
 ////////////////////////////////////////////////////////
 -(void)enableKeyRepeat
 {

src/SFML/Window/OSX/WindowImplCocoa.hpp

@@ -320,6 +320,21 @@ public:
     ////////////////////////////////////////////////////////////
     virtual void setKeyRepeatEnabled(bool enabled);
 
+    ////////////////////////////////////////////////////////////
+    /// \brief Request the current window to be made the active
+    ///        foreground window
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual void requestFocus();
+
+    ////////////////////////////////////////////////////////////
+    /// \brief Check 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)
 }
 
 
+////////////////////////////////////////////////////////////
+void WindowImplCocoa::requestFocus()
+{
+    [m_delegate requestFocus];
+}
+
+
+////////////////////////////////////////////////////////////
+bool WindowImplCocoa::hasFocus() const
+{
+    return [m_delegate hasFocus];
+}
+
+
 } // namespace priv
 
 } // namespace sf

src/SFML/Window/OSX/WindowImplDelegateProtocol.h

@@ -166,6 +166,21 @@ namespace sf {
 ////////////////////////////////////////////////////////////
 -(void)closeWindow;
 
+////////////////////////////////////////////////////////////
+/// \brief Request the current window to be made the active
+///        foreground window
+///
+////////////////////////////////////////////////////////////
+-(void)requestFocus;
+
+////////////////////////////////////////////////////////////
+/// \brief Check whether the window has the input focus
+///
+/// \return True if window has focus, false otherwise
+///
+////////////////////////////////////////////////////////////
+-(BOOL)hasFocus;
+
 ////////////////////////////////////////////////////////////
 /// \brief Enable key repeat
 ///

src/SFML/Window/Unix/WindowImplX11.cpp

@@ -40,6 +40,7 @@
 #include <vector>
 #include <string>
 #include <iterator>
+#include <algorithm>
 
 #ifdef SFML_OPENGL_ES
     #include <SFML/Window/EglContext.hpp>
@@ -55,6 +56,7 @@
 namespace
 {
     sf::priv::WindowImplX11*              fullscreenWindow = NULL;
+    std::vector<sf::priv::WindowImplX11*> allWindows;
     unsigned long                         eventMask        = FocusChangeMask | ButtonPressMask | ButtonReleaseMask | ButtonMotionMask |
                                                              PointerMotionMask | KeyPressMask | KeyReleaseMask | StructureNotifyMask |
                                                              EnterWindowMask | LeaveWindowMask;
@@ -303,6 +305,9 @@ WindowImplX11::~WindowImplX11()
 
     // Close the connection with the X server
     CloseDisplay(m_display);
+
+    // Remove this window from the global list of windows (required for focus request)
+    allWindows.erase(std::find(allWindows.begin(), allWindows.end(), this));
 }
 
 
@@ -483,6 +488,67 @@ void WindowImplX11::setKeyRepeatEnabled(bool enabled)
 }
 
 
+////////////////////////////////////////////////////////////
+void WindowImplX11::requestFocus()
+{
+    // Focus is only stolen among SFML windows, not between applications
+    // Check the global list of windows to find out whether an SFML window has the focus
+    // Note: can't handle console and other non-SFML windows belonging to the application.
+    bool sfmlWindowFocused = false;
+    for (std::vector<WindowImplX11*>::iterator itr = allWindows.begin(); itr != allWindows.end(); ++itr)
+    {
+        if ((*itr)->hasFocus())
+        {
+            sfmlWindowFocused = true;
+            break;
+        }
+    }
+    
+    // Check if window is viewable (not on other desktop, ...)
+    // TODO: Check also if minimized
+    XWindowAttributes attributes;
+    if (XGetWindowAttributes(m_display, m_window, &attributes) == 0)
+    {
+        sf::err() << "Failed to check if window is viewable while requesting focus" << std::endl;
+        return; // error getting attribute
+    }
+
+    bool windowViewable = (attributes.map_state == IsViewable);
+    
+    if (sfmlWindowFocused && windowViewable)
+    {
+        // Another SFML window of this application has the focus and the current window is viewable:
+        // steal focus (i.e. bring window to the front and give it input focus)
+        XRaiseWindow(m_display, m_window);
+        XSetInputFocus(m_display, m_window, RevertToPointerRoot, CurrentTime);
+    }
+    else
+    {
+        // Otherwise: display urgency hint (flashing application logo)
+        // Ensure WM hints exist, allocate if necessary
+        XWMHints* hints = XGetWMHints(m_display, m_window);
+        if (hints == NULL)
+            hints = XAllocWMHints();
+        
+        // Add urgency (notification) flag to hints
+        hints->flags |= XUrgencyHint;
+        XSetWMHints(m_display, m_window, hints);
+        XFree(hints);
+    }
+}
+
+
+////////////////////////////////////////////////////////////
+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)
 {
@@ -568,6 +634,9 @@ void WindowImplX11::initialize()
 
     // Flush the commands queue
     XFlush(m_display);
+    
+    // Add this window to the global list of windows (required for focus request)
+    allWindows.push_back(this);
 }
 
 
@@ -680,6 +749,16 @@ bool WindowImplX11::processEvent(XEvent windowEvent)
             Event event;
             event.type = Event::GainedFocus;
             pushEvent(event);
+
+            // If the window has been previously marked urgent (notification) as a result of a focus request, undo that
+            XWMHints* hints = XGetWMHints(m_display, m_window);
+            if (hints != NULL)
+            {
+                // Remove urgency (notification) flag from hints
+                hints->flags &= ~XUrgencyHint;
+                XSetWMHints(m_display, m_window, hints);
+                XFree(hints);
+            }
             break;
         }
 

src/SFML/Window/Unix/WindowImplX11.hpp

@@ -154,6 +154,21 @@ public:
     ////////////////////////////////////////////////////////////
     virtual void setKeyRepeatEnabled(bool enabled);
 
+    ////////////////////////////////////////////////////////////
+    /// \brief Request the current window to be made the active
+    ///        foreground window
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual void requestFocus();
+
+    ////////////////////////////////////////////////////////////
+    /// \brief Check 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 +366,40 @@ void WindowImplWin32::setKeyRepeatEnabled(bool enabled)
 }
 
 
+////////////////////////////////////////////////////////////
+void WindowImplWin32::requestFocus()
+{
+    // Allow focus stealing only within the same process; compare PIDs of current and foreground window
+    DWORD thisPid       = GetWindowThreadProcessId(m_handle, NULL);
+    DWORD foregroundPid = GetWindowThreadProcessId(GetForegroundWindow(), NULL);
+     
+    if (thisPid == foregroundPid)
+    {
+        // The window requesting focus belongs to the same process as the current window: steal focus
+        SetForegroundWindow(m_handle);
+    }
+    else
+    {
+        // Different process: don't steal focus, but create a taskbar notification ("flash")
+        FLASHWINFO info;
+        info.cbSize    = sizeof(info);
+        info.hwnd      = m_handle;
+        info.dwFlags   = FLASHW_TRAY;
+        info.dwTimeout = 0;
+        info.uCount    = 3;
+
+        FlashWindowEx(&info);
+    }
+}
+
+
+////////////////////////////////////////////////////////////
+bool WindowImplWin32::hasFocus() const
+{
+    return m_handle == GetForegroundWindow();
+}
+
+
 ////////////////////////////////////////////////////////////
 void WindowImplWin32::registerWindowClass()
 {

src/SFML/Window/Win32/WindowImplWin32.hpp

@@ -153,6 +153,21 @@ public:
     ////////////////////////////////////////////////////////////
     virtual void setKeyRepeatEnabled(bool enabled);
 
+    ////////////////////////////////////////////////////////////
+    /// \brief Request the current window to be made the active
+    ///        foreground window
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual void requestFocus();
+
+    ////////////////////////////////////////////////////////////
+    /// \brief Check 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 +337,22 @@ bool Window::setActive(bool active) const
 
 
 ////////////////////////////////////////////////////////////
+void Window::requestFocus()
+{
+    if (m_impl)
+        m_impl->requestFocus();
+}
+
+
+////////////////////////////////////////////////////////////
+bool Window::hasFocus() const
+{
+    return m_impl && m_impl->hasFocus();
+}
+
+
+////////////////////////////////////////////////////////////
+
 void Window::display()
 {
     // Display the backbuffer on screen

src/SFML/Window/WindowImpl.hpp

@@ -194,6 +194,21 @@ public:
     ////////////////////////////////////////////////////////////
     virtual void setKeyRepeatEnabled(bool enabled) = 0;
 
+    ////////////////////////////////////////////////////////////
+    /// \brief Request the current window to be made the active
+    ///        foreground window
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual void requestFocus() = 0;
+
+    ////////////////////////////////////////////////////////////
+    /// \brief Check whether the window has the input focus
+    ///
+    /// \return True if window has focus, false otherwise
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual bool hasFocus() const = 0;
+
 protected:
 
     ////////////////////////////////////////////////////////////

src/SFML/Window/iOS/WindowImplUIKit.hpp

@@ -157,6 +157,21 @@ public:
     ////////////////////////////////////////////////////////////
     virtual void setKeyRepeatEnabled(bool enabled);
 
+    ////////////////////////////////////////////////////////////
+    /// \brief Request the current window to be made the active
+    ///        foreground window
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual void requestFocus();
+
+    ////////////////////////////////////////////////////////////
+    /// \brief Check whether the window has the input focus
+    ///
+    /// \return True if window has focus, false otherwise
+    ///
+    ////////////////////////////////////////////////////////////
+    virtual bool hasFocus() const;
+
 public:
 
     using WindowImpl::pushEvent;

src/SFML/Window/iOS/WindowImplUIKit.mm

@@ -170,6 +170,21 @@ void WindowImplUIKit::setKeyRepeatEnabled(bool enabled)
 }
 
 
+////////////////////////////////////////////////////////////
+void WindowImplUIKit::requestFocus()
+{
+    // Not applicable
+}
+
+
+////////////////////////////////////////////////////////////
+bool WindowImplUIKit::hasFocus() const
+{
+    // Not applicable
+    return false;
+}
+
+    
 ////////////////////////////////////////////////////////////
 SFView* WindowImplUIKit::getGlView() const
 {