src/screen.h

   1 /***************************************************************************
   2  *   Copyright (C) 2008-2012 by Andrzej Rybczak                            *
   3  *   electricityispower@gmail.com                                          *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.              *
  19  ***************************************************************************/
  20
  21 #ifndef _SCREEN_H
  22 #define _SCREEN_H
  23
  24 #include "menu.h"
  25 #include "scrollpad.h"
  26
  27 void GenericMouseButtonPressed(NC::Window *w, MEVENT me);
  28 void ScrollpadMouseButtonPressed(NC::Scrollpad *w, MEVENT me);
  29
  30 /// An interface for various instantiations of Screen template class. Since C++ doesn't like
  31 /// comparison of two different instantiations of the same template class we need the most
  32 /// basic class to be non-template to allow it.
  33 ///
  34 class BasicScreen
  35 {
  36         public:
  37                 /// Initializes all variables to zero
  38                 ///
  39                 BasicScreen() : hasToBeResized(0), isInitialized(0) { }
  40
  41                 virtual ~BasicScreen() { }
  42
  43                 /// @see Screen::ActiveWindow()
  44                 virtual NC::Window *ActiveWindow() = 0;
  45
  46                 /// Method used for switching to screen
  47                 virtual void SwitchTo() = 0;
  48
  49                 /// Method that should resize screen
  50                 /// if requested by hasToBeResized
  51                 virtual void Resize() = 0;
  52
  53                 /// @return title of the screen
  54                 virtual std::basic_string<my_char_t> Title() = 0;
  55
  56                 /// If the screen contantly has to update itself
  57                 /// somehow, it should be called by this function.
  58                 virtual void Update() { }
  59
  60                 /// @see Screen::Refresh()
  61                 virtual void Refresh() = 0;
  62
  63                 /// @see Screen::RefreshWindow()
  64                 virtual void RefreshWindow() = 0;
  65
  66                 /// @see Screen::Scroll()
  67                 virtual void Scroll(NC::Where where) = 0;
  68
  69                 /// Invoked after Enter was pressed
  70                 virtual void EnterPressed() = 0;
  71
  72                 /// Invoked after Space was pressed
  73                 virtual void SpacePressed() = 0;
  74
  75                 /// @see Screen::MouseButtonPressed()
  76                 virtual void MouseButtonPressed(MEVENT) { }
  77
  78                 /// When this is overwritten with a function returning true, the
  79                 /// screen will be used in tab switching.
  80                 virtual bool isTabbable() { return false; }
  81
  82                 /// @return true if screen is mergable, ie. can be "proper" subwindow
  83                 /// if one of the screens is locked. Screens that somehow resemble popups
  84                 /// will want to return false here.
  85                 virtual bool isMergable() = 0;
  86
  87                 /// Locks current screen.
  88                 /// @return true if lock was successful, false otherwise. Note that
  89                 /// if there is already locked screen, it'll not overwrite it.
  90                 bool Lock();
  91
  92                 /// Should be set to true each time screen needs resize
  93                 bool hasToBeResized;
  94
  95                 /// Unlocks a screen, ie. hides merged window (if there is one set).
  96                 static void Unlock();
  97
  98         protected:
  99                 /// Since screens initialization is lazy, we don't want to do
 100                 /// this in the constructor. This function should be invoked
 101                 /// only once and after that isInitialized flag has to be set
 102                 /// to true to somehow avoid next attempt of initialization.
 103                 ///
 104                 virtual void Init() = 0;
 105
 106                 /// @return true if screen can be locked. Note that returning
 107                 /// false here doesn't neccesarily mean that screen is also not
 108                 /// mergable (eg. lyrics screen is not lockable since that wouldn't
 109                 /// make much sense, but it's perfectly fine to merge it).
 110                 virtual bool isLockable() = 0;
 111
 112                 /// Gets X offset and width of current screen to be used eg. in Resize() function.
 113                 /// @param adjust_locked_screen indicates whether this function should
 114                 /// automatically adjust locked screen's dimensions (if there is one set)
 115                 /// if current screen is going to be subwindow.
 116                 void GetWindowResizeParams(size_t &x_offset, size_t &width, bool adjust_locked_screen = true);
 117
 118                 /// Flag that inditates whether the screen is initialized or not
 119                 ///
 120                 bool isInitialized;
 121 };
 122
 123 void ApplyToVisibleWindows(void (BasicScreen::*f)());
 124 void UpdateInactiveScreen(BasicScreen *screen_to_be_set);
 125 bool isVisible(BasicScreen *screen);
 126
 127 /// Class that all screens should derive from. It provides basic interface
 128 /// for the screen to be working properly and assumes that we didn't forget
 129 /// about anything vital.
 130 ///
 131 template <typename WindowType> class Screen : public BasicScreen
 132 {
 133         public:
 134                 Screen() : w(0) { }
 135                 virtual ~Screen() { }
 136
 137                 /// Since some screens contain more that one window
 138                 /// it's useful to determine the one that is being
 139                 /// active
 140                 /// @return address to window object cast to void *
 141                 virtual NC::Window *ActiveWindow();
 142
 143                 /// @return pointer to currently active window
 144                 WindowType *Main();
 145
 146                 /// Refreshes whole screen
 147                 virtual void Refresh();
 148
 149                 /// Refreshes active window of the screen
 150                 virtual void RefreshWindow();
 151
 152                 /// Scrolls the screen by given amount of lines and
 153                 /// if fancy scrolling feature is disabled, enters the
 154                 /// loop that holds main loop until user releases the key
 155                 /// @param where indicates where one wants to scroll
 156                 virtual void Scroll(NC::Where where);
 157
 158                 /// Invoked after there was one of mouse buttons pressed
 159                 /// @param me struct that contains coords of where the click
 160                 /// had its place and button actions
 161                 virtual void MouseButtonPressed(MEVENT me);
 162
 163         protected:
 164                 /// Template parameter that should indicate the main type
 165                 /// of window used by the screen. What is more, it should
 166                 /// always be assigned to the currently active window (if
 167                 /// acreen contains more that one)
 168                 WindowType *w;
 169 };
 170
 171 template <typename WindowType> NC::Window *Screen<WindowType>::ActiveWindow()
 172 {
 173         return w;
 174 }
 175
 176 template <typename WindowType> WindowType *Screen<WindowType>::Main()
 177 {
 178         return w;
 179 }
 180
 181 template <typename WindowType> void Screen<WindowType>::Refresh()
 182 {
 183         w->Display();
 184 }
 185
 186 template <typename WindowType> void Screen<WindowType>::RefreshWindow()
 187 {
 188         w->Display();
 189 }
 190
 191 template <typename WindowType> void Screen<WindowType>::Scroll(NC::Where where)
 192 {
 193         w->Scroll(where);
 194 }
 195
 196 template <typename WindowType> void Screen<WindowType>::MouseButtonPressed(MEVENT me)
 197 {
 198         GenericMouseButtonPressed(w, me);
 199 }
 200
 201 /// Specialization for Screen<Scrollpad>::MouseButtonPressed, that should
 202 /// not scroll whole page, but rather a few lines (the number of them is
 203 /// defined in the config)
 204 template <> inline void Screen<NC::Scrollpad>::MouseButtonPressed(MEVENT me)
 205 {
 206         ScrollpadMouseButtonPressed(w, me);
 207 }
 208
 209 #endif
 210