GNU Octave  6.2.0
A high-level interpreted language, primarily intended for numerical computations, mostly compatible with Matlab
ScreenWindow.h
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1 /*
2  Copyright (C) 2007, 2013 by Robert Knight <robertknight@gmail.com>
3 
4  Rewritten for QT4 by e_k <e_k at users.sourceforge.net>, Copyright (C)2008
5 
6  This program is free software: you can redistribute it and/or modify
7  it under the terms of the GNU General Public License as published by
8  the Free Software Foundation; either version 2 of the License, or
9  (at your option) any later version.
10 
11  This program is distributed in the hope that it will be useful,
12  but WITHOUT ANY WARRANTY; without even the implied warranty of
13  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  GNU General Public License for more details.
15 
16  You should have received a copy of the GNU General Public License
17  along with this program; if not, write to the Free Software
18  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
19  02110-1301 USA.
20 */
21 
22 #ifndef SCREENWINDOW_H
23 #define SCREENWINDOW_H
24 
25 // Qt
26 #include <QtCore/QObject>
27 #include <QtCore/QPoint>
28 #include <QtCore/QRect>
29 
30 // Konsole
31 #include "unix/Character.h"
32 
33 class Screen;
34 
35 /**
36  * Provides a window onto a section of a terminal screen.
37  * This window can then be rendered by a terminal display widget ( TerminalDisplay ).
38  *
39  * To use the screen window, create a new ScreenWindow() instance and associated it with
40  * a terminal screen using setScreen().
41  * Use the scrollTo() method to scroll the window up and down on the screen.
42  * Call the getImage() method to retrieve the character image which is currently visible in the window.
43  *
44  * setTrackOutput() controls whether the window moves to the bottom of the associated screen when new
45  * lines are added to it.
46  *
47  * Whenever the output from the underlying screen is changed, the notifyOutputChanged() slot should
48  * be called. This in turn will update the window's position and emit the outputChanged() signal
49  * if necessary.
50  */
51 class ScreenWindow : public QObject
52 {
53 Q_OBJECT
54 
55 public:
56  /**
57  * Constructs a new screen window with the given parent.
58  * A screen must be specified by calling setScreen() before calling getImage() or getLineProperties().
59  *
60  * You should not call this constructor directly, instead use the Emulation::createWindow() method
61  * to create a window on the emulation which you wish to view. This allows the emulation
62  * to notify the window when the associated screen has changed and synchronize selection updates
63  * between all views on a session.
64  */
65  ScreenWindow(QObject* parent = nullptr);
66  virtual ~ScreenWindow();
67 
68  /** Sets the screen which this window looks onto */
69  void setScreen(Screen* screen);
70  /** Returns the screen which this window looks onto */
71  Screen* screen() const;
72 
73  /**
74  * Returns the image of characters which are currently visible through this window
75  * onto the screen.
76  *
77  * The buffer is managed by the ScreenWindow instance and does not need to be
78  * deleted by the caller.
79  */
81 
82  /**
83  * Returns the line attributes associated with the lines of characters which
84  * are currently visible through this window
85  */
86  QVector<LineProperty> getLineProperties();
87 
88  /**
89  * Returns the number of lines which the region of the window
90  * specified by scrollRegion() has been scrolled by since the last call
91  * to resetScrollCount(). scrollRegion() is in most cases the
92  * whole window, but will be a smaller area in, for example, applications
93  * which provide split-screen facilities.
94  *
95  * This is not guaranteed to be accurate, but allows views to optimise
96  * rendering by reducing the amount of costly text rendering that
97  * needs to be done when the output is scrolled.
98  */
99  int scrollCount() const;
100 
101  /**
102  * Resets the count of scrolled lines returned by scrollCount()
103  */
104  void resetScrollCount();
105 
106  /**
107  * Returns the area of the window which was last scrolled, this is
108  * usually the whole window area.
109  *
110  * Like scrollCount(), this is not guaranteed to be accurate,
111  * but allows views to optimise rendering.
112  */
113  QRect scrollRegion() const;
114 
115  /**
116  * Sets the start of the selection to the given @p line and @p column within
117  * the window.
118  */
119  void setSelectionStart( int column , int line , bool columnMode );
120  /**
121  * Sets the end of the selection to the given @p line and @p column within
122  * the window.
123  */
124  void setSelectionEnd( int column , int line );
125  /**
126  * Retrieves the start of the selection within the window.
127  */
128  void getSelectionStart( int& column , int& line );
129  /**
130  * Retrieves the end of the selection within the window.
131  */
132  void getSelectionEnd( int& column , int& line );
133  /**
134  * Returns true if the character at @p line , @p column is part of the selection.
135  */
136  bool isSelected( int column , int line );
137  /**
138  * Clears the current selection
139  */
140  void clearSelection();
141 
142  /** Sets the number of lines in the window */
143  void setWindowLines(int lines);
144  /** Returns the number of lines in the window */
145  int windowLines() const;
146  /** Returns the number of columns in the window */
147  int windowColumns() const;
148 
149  /** Returns the total number of lines in the screen */
150  int lineCount() const;
151  /** Returns the total number of columns in the screen */
152  int columnCount() const;
153 
154  /** Returns the index of the line which is currently at the top of this window */
155  int currentLine() const;
156 
157  /**
158  * Returns the position of the cursor
159  * within the window.
160  */
161  QPoint cursorPosition() const;
162 
163  /**
164  * Convenience method. Returns true if the window is currently at the bottom
165  * of the screen.
166  */
167  bool atEndOfOutput() const;
168 
169  /** Scrolls the window so that @p line is at the top of the window */
170  void scrollTo( int line );
171 
173  {
176  };
177 
178  /**
179  * Scrolls the window relative to its current position on the screen.
180  *
181  * @param mode Specifies whether @p amount refers to the number of lines or the number
182  * of pages to scroll.
183  * @param amount The number of lines or pages ( depending on @p mode ) to scroll by. If
184  * this number is positive, the view is scrolled down. If this number is negative, the view
185  * is scrolled up.
186  */
187  void scrollBy( RelativeScrollMode mode , int amount );
188 
189  /**
190  * Specifies whether the window should automatically move to the bottom
191  * of the screen when new output is added.
192  *
193  * If this is set to true, the window will be moved to the bottom of the associated screen ( see
194  * screen() ) when the notifyOutputChanged() method is called.
195  */
196  void setTrackOutput(bool trackOutput);
197  /**
198  * Returns whether the window automatically moves to the bottom of the screen as
199  * new output is added. See setTrackOutput()
200  */
201  bool trackOutput() const;
202 
203  /**
204  * Returns the text which is currently selected.
205  *
206  * @param preserveLineBreaks See Screen::selectedText()
207  */
208  QString selectedText( bool preserveLineBreaks ) const;
209 
210 public slots:
211  /**
212  * Notifies the window that the contents of the associated terminal screen have changed.
213  * This moves the window to the bottom of the screen if trackOutput() is true and causes
214  * the outputChanged() signal to be emitted.
215  */
216  void notifyOutputChanged();
217 
218 signals:
219  /**
220  * Emitted when the contents of the associated terminal screen ( see screen() ) changes.
221  */
223 
224  /**
225  * Emitted when the screen window is scrolled to a different position.
226  *
227  * @param line The line which is now at the top of the window.
228  */
229  void scrolled(int line);
230 
231  /**
232  * Emitted when the selection is changed.
233  */
235 
236 private:
237  int endWindowLine() const;
238  void fillUnusedArea();
239 
240  Screen* _screen; // see setScreen() , screen()
244 
246  int _currentLine; // see scrollTo() , currentLine()
247  bool _trackOutput; // see setTrackOutput() , trackOutput()
248  int _scrollCount; // count of lines which the window has been scrolled by since
249  // the last call to resetScrollCount()
250 };
251 
252 #endif // SCREENWINDOW_H
A single character in the terminal which consists of a unicode character value, foreground and backgr...
Definition: Character.h:56
Provides a window onto a section of a terminal screen.
Definition: ScreenWindow.h:52
void fillUnusedArea()
Character * getImage()
Returns the image of characters which are currently visible through this window onto the screen.
void setSelectionStart(int column, int line, bool columnMode)
Sets the start of the selection to the given line and column within the window.
void setSelectionEnd(int column, int line)
Sets the end of the selection to the given line and column within the window.
void getSelectionEnd(int &column, int &line)
Retrieves the end of the selection within the window.
void setTrackOutput(bool trackOutput)
Specifies whether the window should automatically move to the bottom of the screen when new output is...
QRect scrollRegion() const
Returns the area of the window which was last scrolled, this is usually the whole window area.
int windowLines() const
Returns the number of lines in the window.
void scrolled(int line)
Emitted when the screen window is scrolled to a different position.
int currentLine() const
Returns the index of the line which is currently at the top of this window.
bool atEndOfOutput() const
Convenience method.
bool _bufferNeedsUpdate
Definition: ScreenWindow.h:243
bool isSelected(int column, int line)
Returns true if the character at line , column is part of the selection.
int lineCount() const
Returns the total number of lines in the screen.
void getSelectionStart(int &column, int &line)
Retrieves the start of the selection within the window.
int columnCount() const
Returns the total number of columns in the screen.
void clearSelection()
Clears the current selection.
QString selectedText(bool preserveLineBreaks) const
Returns the text which is currently selected.
int endWindowLine() const
Character * _windowBuffer
Definition: ScreenWindow.h:241
int windowColumns() const
Returns the number of columns in the window.
Screen * _screen
Definition: ScreenWindow.h:240
int _windowBufferSize
Definition: ScreenWindow.h:242
bool trackOutput() const
Returns whether the window automatically moves to the bottom of the screen as new output is added.
ScreenWindow(QObject *parent=nullptr)
Constructs a new screen window with the given parent.
void setScreen(Screen *screen)
Sets the screen which this window looks onto.
void notifyOutputChanged()
Notifies the window that the contents of the associated terminal screen have changed.
QPoint cursorPosition() const
Returns the position of the cursor within the window.
void selectionChanged()
Emitted when the selection is changed.
void scrollBy(RelativeScrollMode mode, int amount)
Scrolls the window relative to its current position on the screen.
int scrollCount() const
Returns the number of lines which the region of the window specified by scrollRegion() has been scrol...
void scrollTo(int line)
Scrolls the window so that line is at the top of the window.
void resetScrollCount()
Resets the count of scrolled lines returned by scrollCount()
Screen * screen() const
Returns the screen which this window looks onto.
void outputChanged()
Emitted when the contents of the associated terminal screen ( see screen() ) changes.
QVector< LineProperty > getLineProperties()
Returns the line attributes associated with the lines of characters which are currently visible throu...
virtual ~ScreenWindow()
void setWindowLines(int lines)
Sets the number of lines in the window.
An image of characters with associated attributes.
Definition: Screen.h:76