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 class BasicScreen
  34 {
  35         public:
  36                 /// Initializes all variables to zero
  37                 BasicScreen() : hasToBeResized(0), isInitialized(0) { }
  38
  39                 virtual ~BasicScreen() { }
  40
  41                 /// @see Screen::ActiveWindow()
  42                 virtual NC::Window *ActiveWindow() = 0;
  43
  44                 /// @see Screen::Refresh()
  45                 virtual void Refresh() = 0;
  46
  47                 /// @see Screen::RefreshWindow()
  48                 virtual void RefreshWindow() = 0;
  49
  50                 /// @see Screen::Scroll()
  51                 virtual void Scroll(NC::Where where) = 0;
  52
  53                 /// Method used for switching to screen
  54                 virtual void SwitchTo() = 0;
  55
  56                 /// Method that should resize screen
  57                 /// if requested by hasToBeResized
  58                 virtual void Resize() = 0;
  59
  60                 /// @return title of the screen
  61                 virtual std::wstring Title() = 0;
  62
  63                 /// If the screen contantly has to update itself
  64                 /// somehow, it should be called by this function.
  65                 virtual void Update() = 0;
  66
  67                 /// Invoked after Enter was pressed
  68                 virtual void EnterPressed() = 0;
  69
  70                 /// Invoked after Space was pressed
  71                 virtual void SpacePressed() = 0;
  72
  73                 /// @see Screen::MouseButtonPressed()
  74                 virtual void MouseButtonPressed(MEVENT me) = 0;
  75
  76                 /// When this is overwritten with a function returning true, the
  77                 /// screen will be used in tab switching.
  78                 virtual bool isTabbable() = 0;
  79
  80                 /// @return true if screen is mergable, ie. can be "proper" subwindow
  81                 /// if one of the screens is locked. Screens that somehow resemble popups
  82                 /// will want to return false here.
  83                 virtual bool isMergable() = 0;
  84
  85                 /// Locks current screen.
  86                 /// @return true if lock was successful, false otherwise. Note that
  87                 /// if there is already locked screen, it'll not overwrite it.
  88                 bool Lock();
  89
  90                 /// Should be set to true each time screen needs resize
  91                 bool hasToBeResized;
  92
  93                 /// Unlocks a screen, ie. hides merged window (if there is one set).
  94                 static void Unlock();
  95
  96         protected:
  97                 /// Since screens initialization is lazy, we don't want to do
  98                 /// this in the constructor. This function should be invoked
  99                 /// only once and after that isInitialized flag has to be set
 100                 /// to true to somehow avoid next attempt of initialization.
 101                 virtual void Init() = 0;
 102
 103                 /// @return true if screen can be locked. Note that returning
 104                 /// false here doesn't neccesarily mean that screen is also not
 105                 /// mergable (eg. lyrics screen is not lockable since that wouldn't
 106                 /// make much sense, but it's perfectly fine to merge it).
 107                 virtual bool isLockable() = 0;
 108
 109                 /// Gets X offset and width of current screen to be used eg. in Resize() function.
 110                 /// @param adjust_locked_screen indicates whether this function should
 111                 /// automatically adjust locked screen's dimensions (if there is one set)
 112                 /// if current screen is going to be subwindow.
 113                 void GetWindowResizeParams(size_t &x_offset, size_t &width, bool adjust_locked_screen = true);
 114
 115                 /// Flag that inditates whether the screen is initialized or not
 116                 bool isInitialized;
 117 };
 118
 119 void ApplyToVisibleWindows(void (BasicScreen::*f)());
 120 void UpdateInactiveScreen(BasicScreen *screen_to_be_set);
 121 bool isVisible(BasicScreen *screen);
 122
 123 /// Class that all screens should derive from. It provides basic interface
 124 /// for the screen to be working properly and assumes that we didn't forget
 125 /// about anything vital.
 126 ///
 127 template <typename WindowType> class Screen : public BasicScreen
 128 {
 129         public:
 130                 Screen() : w(0) { }
 131                 virtual ~Screen() { }
 132
 133                 /// Since some screens contain more that one window
 134                 /// it's useful to determine the one that is being
 135                 /// active
 136                 /// @return address to window object cast to void *
 137                 virtual NC::Window *ActiveWindow() OVERRIDE {
 138                         return w;
 139                 }
 140
 141                 /// Refreshes whole screen
 142                 virtual void Refresh() OVERRIDE {
 143                         w->display();
 144                 }
 145
 146                 /// Refreshes active window of the screen
 147                 virtual void RefreshWindow() OVERRIDE {
 148                         w->display();
 149                 }
 150
 151                 /// Scrolls the screen by given amount of lines and
 152                 /// if fancy scrolling feature is disabled, enters the
 153                 /// loop that holds main loop until user releases the key
 154                 /// @param where indicates where one wants to scroll
 155                 virtual void Scroll(NC::Where where) OVERRIDE {
 156                         w->scroll(where);
 157                 }
 158
 159                 /// Invoked after there was one of mouse buttons pressed
 160                 /// @param me struct that contains coords of where the click
 161                 /// had its place and button actions
 162                 virtual void MouseButtonPressed(MEVENT me) OVERRIDE {
 163                         GenericMouseButtonPressed(w, me);
 164                 }
 165
 166                 /// @return pointer to currently active window
 167                 WindowType *Main() {
 168                         return w;
 169                 }
 170
 171         protected:
 172                 /// Template parameter that should indicate the main type
 173                 /// of window used by the screen. What is more, it should
 174                 /// always be assigned to the currently active window (if
 175                 /// acreen contains more that one)
 176                 WindowType *w;
 177 };
 178
 179 /// Specialization for Screen<Scrollpad>::MouseButtonPressed, that should
 180 /// not scroll whole page, but rather a few lines (the number of them is
 181 /// defined in the config)
 182 template <> inline void Screen<NC::Scrollpad>::MouseButtonPressed(MEVENT me)
 183 {
 184         ScrollpadMouseButtonPressed(w, me);
 185 }
 186
 187 #endif
 188