cppconsui/TextView.h

   1 // Copyright (C) 2010-2015 Petr Pavlu <setup@dagobah.cz>
   2 //
   3 // This file is part of CenterIM.
   4 //
   5 // CenterIM 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 // CenterIM 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 CenterIM.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 /// @file
  19 /// TextView class.
  20 ///
  21 /// @ingroup cppconsui
  22
  23 #ifndef TEXTVIEW_H
  24 #define TEXTVIEW_H
  25
  26 #include "Widget.h"
  27
  28 #include <deque>
  29
  30 namespace CppConsUI {
  31
  32 /// Line oriented text view widget.
  33 class TextView : public Widget {
  34 public:
  35   TextView(int w, int h, bool autoscroll_ = false, bool scrollbar_ = false);
  36   virtual ~TextView() override;
  37
  38   // Widget
  39   virtual int draw(Curses::ViewPort area, Error &error) override;
  40
  41   /// Appends text after the last line.
  42   virtual void append(const char *text, int color = 0);
  43
  44   /// Inserts text before specified line number. Text can contain multiple lines
  45   /// and should end with the '\n' character just before the '\0' byte.
  46   virtual void insert(std::size_t line_num, const char *text, int color = 0);
  47
  48   /// Removes a specified line.
  49   virtual void erase(std::size_t line_num);
  50
  51   /// Removes specified range of lines. Parameter end_line represents the line
  52   /// after the last removed line, thus range of <start_line, end_line) lines is
  53   /// removed.
  54   virtual void erase(std::size_t start_line, std::size_t end_line);
  55
  56   /// Removes all lines.
  57   virtual void clear();
  58
  59   /// Returns string for a specified line number.
  60   virtual const char *getLine(std::size_t line_num) const;
  61
  62   /// Returns count of all lines.
  63   virtual std::size_t getLinesNumber() const;
  64
  65   virtual void setAutoScroll(bool new_autoscroll);
  66   virtual bool hasAutoScroll() const { return autoscroll_; }
  67
  68   virtual void setScrollBar(bool new_scrollbar);
  69   virtual bool hasScrollBar() const { return scrollbar_; }
  70
  71 protected:
  72   /// Struct Line saves a real line. All text added into TextView is split on
  73   /// '\\n' character and stored into Line objects.
  74   struct Line {
  75     /// UTF-8 encoded text. Note: Newline character is not part of text.
  76     char *text;
  77
  78     /// Text length in characters.
  79     std::size_t length;
  80
  81     /// Color number.
  82     int color;
  83
  84     Line(const char *text_, std::size_t bytes, int color_);
  85     virtual ~Line();
  86   };
  87
  88   /// ScreenLine represents an on-screen line.
  89   struct ScreenLine {
  90     /// Parent Line that this ScreenLine shows.
  91     Line *parent;
  92
  93     /// Pointer into parent's text where this ScreenLine starts.
  94     const char *text;
  95
  96     /// Length in characters (Unicode).
  97     int length;
  98
  99     ScreenLine(Line &parent_, const char *text_, int length_);
 100   };
 101
 102   typedef std::deque<Line *> Lines;
 103   typedef std::deque<ScreenLine> ScreenLines;
 104
 105   std::size_t view_top_;
 106   bool autoscroll_;
 107   bool autoscroll_suspended_;
 108   bool scrollbar_;
 109
 110   /// Array of real lines.
 111   Lines lines_;
 112
 113   /// Array of on-screen lines.
 114   ScreenLines screen_lines_;
 115
 116   // Widget
 117   virtual void updateArea() override;
 118
 119   virtual const char *proceedLine(
 120     const char *text, int area_width, int *res_length) const;
 121
 122   /// Recalculates on-screen lines for a specified line number.
 123   virtual std::size_t updateScreenLines(
 124     std::size_t line_num, std::size_t start = 0);
 125
 126   /// Recalculates all screen lines.
 127   virtual void updateAllScreenLines();
 128
 129   virtual std::size_t eraseScreenLines(std::size_t line_num,
 130     std::size_t start = 0, std::size_t *deleted = nullptr);
 131
 132 private:
 133   CONSUI_DISABLE_COPY(TextView);
 134
 135   void actionScroll(int direction);
 136
 137   void declareBindables();
 138 };
 139
 140 } // namespace CppConsUI
 141
 142 #endif // TEXTVIEW_H
 143
 144 // vim: set tabstop=2 shiftwidth=2 textwidth=80 expandtab: