src/Widget/CallbackWidget.hpp

   1 /*
   2 Copyright_License {
   3
   4   XCSoar Glide Computer - http://www.xcsoar.org/
   5   Copyright (C) 2000-2013 The XCSoar Project
   6   A detailed list of copyright holders can be found in the file "AUTHORS".
   7
   8   This program is free software; you can redistribute it and/or
   9   modify it under the terms of the GNU General Public License
  10   as published by the Free Software Foundation; either version 2
  11   of the License, or (at your option) any later version.
  12
  13   This program is distributed in the hope that it will be useful,
  14   but WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16   GNU General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with this program; if not, write to the Free Software
  20   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  21 }
  22 */
  23
  24 #ifndef XCSOAR_CALLBACK_WIDGET_HPP
  25 #define XCSOAR_CALLBACK_WIDGET_HPP
  26
  27 #include "Screen/Features.hpp"
  28
  29 #ifdef HAVE_CLIPPING
  30 #include "PanelWidget.hpp"
  31 #else
  32 #include "Widget.hpp"
  33 #endif
  34
  35 /**
  36  * A #Widget implementation that invokes a callback when clicked.  It
  37  * has no visual representation.
  38  */
  39 class CallbackWidget
  40 #ifdef HAVE_CLIPPING
  41 /* need PanelWidget on GDI so dialog background gets rendered in the
  42    Widget area just in case this Widget becomes "visible", to avoid
  43    uninitialised screen area */
  44   : public PanelWidget
  45 #else
  46 /* on OpenGL, we can avoid the overhead of creating a panel window */
  47   : public NullWidget
  48 #endif
  49 {
  50   void (*const callback)();
  51
  52 public:
  53   CallbackWidget(void (*_callback)())
  54     :callback(_callback) {}
  55
  56 public:
  57   virtual bool Click() override;
  58   virtual void ReClick() override;
  59
  60 #ifndef HAVE_CLIPPING
  61   virtual void Show(const PixelRect &rc) override;
  62   virtual void Hide() override;
  63 #endif
  64 };
  65
  66 #endif