]>
Commit | Line | Data |
---|---|---|
1 | ///////////////////////////////////////////////////////////////////////////// | |
2 | // Name: include/wx/vscroll.h | |
3 | // Purpose: wxVScrolledWindow: generalization of wxScrolledWindow | |
4 | // Author: Vadim Zeitlin | |
5 | // Modified by: | |
6 | // Created: 30.05.03 | |
7 | // RCS-ID: $Id$ | |
8 | // Copyright: (c) 2003 Vadim Zeitlin <vadim@wxwidgets.org> | |
9 | // Licence: wxWindows licence | |
10 | ///////////////////////////////////////////////////////////////////////////// | |
11 | ||
12 | #ifndef _WX_VSCROLL_H_ | |
13 | #define _WX_VSCROLL_H_ | |
14 | ||
15 | #include "wx/panel.h" // base class | |
16 | ||
17 | // ---------------------------------------------------------------------------- | |
18 | // wxVScrolledWindow | |
19 | // ---------------------------------------------------------------------------- | |
20 | ||
21 | /* | |
22 | In the name of this class, "V" may stand for "variable" because it can be | |
23 | used for scrolling lines of variable heights; "virtual" because it is not | |
24 | necessary to know the heights of all lines in advance -- only those which | |
25 | are shown on the screen need to be measured; or, even, "vertical" because | |
26 | this class only supports scrolling in one direction currently (this could | |
27 | and probably will change in the future however). | |
28 | ||
29 | In any case, this is a generalization of the wxScrolledWindow class which | |
30 | can be only used when all lines have the same height. It lacks some other | |
31 | wxScrolledWindow features however, notably it currently lacks support for | |
32 | horizontal scrolling; it can't scroll another window nor only a rectangle | |
33 | of the window and not its entire client area. | |
34 | */ | |
35 | class WXDLLEXPORT wxVScrolledWindow : public wxPanel | |
36 | { | |
37 | public: | |
38 | // constructors and such | |
39 | // --------------------- | |
40 | ||
41 | // default ctor, you must call Create() later | |
42 | wxVScrolledWindow() { Init(); } | |
43 | ||
44 | // normal ctor, no need to call Create() after this one | |
45 | // | |
46 | // note that wxVSCROLL is always automatically added to our style, there is | |
47 | // no need to specify it explicitly | |
48 | wxVScrolledWindow(wxWindow *parent, | |
49 | wxWindowID id = wxID_ANY, | |
50 | const wxPoint& pos = wxDefaultPosition, | |
51 | const wxSize& size = wxDefaultSize, | |
52 | long style = 0, | |
53 | const wxString& name = wxPanelNameStr) | |
54 | { | |
55 | Init(); | |
56 | ||
57 | (void)Create(parent, id, pos, size, style, name); | |
58 | } | |
59 | ||
60 | // same as the previous ctor but returns status code: true if ok | |
61 | // | |
62 | // just as with the ctor above, wxVSCROLL style is always used, there is no | |
63 | // need to specify it | |
64 | bool Create(wxWindow *parent, | |
65 | wxWindowID id = wxID_ANY, | |
66 | const wxPoint& pos = wxDefaultPosition, | |
67 | const wxSize& size = wxDefaultSize, | |
68 | long style = 0, | |
69 | const wxString& name = wxPanelNameStr) | |
70 | { | |
71 | return wxPanel::Create(parent, id, pos, size, style | wxVSCROLL, name); | |
72 | } | |
73 | ||
74 | ||
75 | // operations | |
76 | // ---------- | |
77 | ||
78 | // set the number of lines the window contains: the derived class must | |
79 | // provide the heights for all lines with indices up to the one given here | |
80 | // in its OnGetLineHeight() | |
81 | void SetLineCount(size_t count); | |
82 | ||
83 | // scroll to the specified line: it will become the first visible line in | |
84 | // the window | |
85 | // | |
86 | // return true if we scrolled the window, false if nothing was done | |
87 | bool ScrollToLine(size_t line); | |
88 | ||
89 | // scroll by the specified number of lines/pages | |
90 | virtual bool ScrollLines(int lines); | |
91 | virtual bool ScrollPages(int pages); | |
92 | ||
93 | // redraw the specified line | |
94 | virtual void RefreshLine(size_t line); | |
95 | ||
96 | // redraw all lines in the specified range (inclusive) | |
97 | virtual void RefreshLines(size_t from, size_t to); | |
98 | ||
99 | // return the item at the specified (in physical coordinates) position or. | |
100 | ||
101 | // wxNOT_FOUND if none, i.e. if it is below the last item | |
102 | int HitTest(wxCoord x, wxCoord y) const; | |
103 | int HitTest(const wxPoint& pt) const { return HitTest(pt.x, pt.y); } | |
104 | ||
105 | // recalculate all our parameters and redisplay all lines | |
106 | virtual void RefreshAll(); | |
107 | ||
108 | ||
109 | // accessors | |
110 | // --------- | |
111 | ||
112 | // get the number of lines this window contains (previously set by | |
113 | // SetLineCount()) | |
114 | size_t GetLineCount() const { return m_lineMax; } | |
115 | ||
116 | // get the first currently visible line | |
117 | size_t GetVisibleBegin() const { return m_lineFirst; } | |
118 | ||
119 | // get the first currently visible line | |
120 | size_t GetVisibleEnd() const { return m_lineFirst + m_nVisible; } | |
121 | ||
122 | // is this line currently visible? | |
123 | bool IsVisible(size_t line) const | |
124 | { return line >= GetVisibleBegin() && line < GetVisibleEnd(); } | |
125 | ||
126 | ||
127 | // this is the same as GetVisibleBegin(), exists to match | |
128 | // GetLastVisibleLine() and for backwards compatibility only | |
129 | size_t GetFirstVisibleLine() const { return m_lineFirst; } | |
130 | ||
131 | // get the last currently visible line | |
132 | // | |
133 | // this function is unsafe as it returns (size_t)-1 (i.e. a huge positive | |
134 | // number) if the control is empty, use GetVisibleEnd() instead, this one | |
135 | // is kept for backwards compatibility | |
136 | size_t GetLastVisibleLine() const { return GetVisibleEnd() - 1; } | |
137 | ||
138 | ||
139 | protected: | |
140 | // this function must be overridden in the derived class and it should | |
141 | // return the height of the given line in pixels | |
142 | virtual wxCoord OnGetLineHeight(size_t n) const = 0; | |
143 | ||
144 | // this function doesn't have to be overridden but it may be useful to do | |
145 | // it if calculating the lines heights is a relatively expensive operation | |
146 | // as it gives the user code a possibility to calculate several of them at | |
147 | // once | |
148 | // | |
149 | // OnGetLinesHint() is normally called just before OnGetLineHeight() but you | |
150 | // shouldn't rely on the latter being called for all lines in the interval | |
151 | // specified here. It is also possible that OnGetLineHeight() will be | |
152 | // called for the lines outside of this interval, so this is really just a | |
153 | // hint, not a promise. | |
154 | // | |
155 | // finally note that lineMin is inclusive, while lineMax is exclusive, as | |
156 | // usual | |
157 | virtual void OnGetLinesHint(size_t WXUNUSED(lineMin), | |
158 | size_t WXUNUSED(lineMax)) const { } | |
159 | ||
160 | // when the number of lines changes, we try to estimate the total height | |
161 | // of all lines which is a rather expensive operation in terms of lines | |
162 | // access, so if the user code may estimate the average height | |
163 | // better/faster than we do, it should override this function to implement | |
164 | // its own logic | |
165 | // | |
166 | // this function should return the best guess for the total height it may | |
167 | // make | |
168 | virtual wxCoord EstimateTotalHeight() const; | |
169 | ||
170 | ||
171 | // the event handlers | |
172 | void OnSize(wxSizeEvent& event); | |
173 | void OnScroll(wxScrollWinEvent& event); | |
174 | #if wxUSE_MOUSEWHEEL | |
175 | void OnMouseWheel(wxMouseEvent& event); | |
176 | #endif | |
177 | ||
178 | // find the index of the line we need to show at the top of the window such | |
179 | // that the last (fully or partially) visible line is the given one | |
180 | size_t FindFirstFromBottom(size_t lineLast, bool fullyVisible = false); | |
181 | ||
182 | // get the total height of the lines between lineMin (inclusive) and | |
183 | // lineMax (exclusive) | |
184 | wxCoord GetLinesHeight(size_t lineMin, size_t lineMax) const; | |
185 | ||
186 | // update the thumb size shown by the scrollbar | |
187 | void UpdateScrollbar(); | |
188 | ||
189 | private: | |
190 | // common part of all ctors | |
191 | void Init(); | |
192 | ||
193 | ||
194 | // the total number of (logical) lines | |
195 | size_t m_lineMax; | |
196 | ||
197 | // the total (estimated) height | |
198 | wxCoord m_heightTotal; | |
199 | ||
200 | // the first currently visible line | |
201 | size_t m_lineFirst; | |
202 | ||
203 | // the number of currently visible lines (including the last, possibly only | |
204 | // partly, visible one) | |
205 | size_t m_nVisible; | |
206 | ||
207 | // accumulated mouse wheel rotation | |
208 | #if wxUSE_MOUSEWHEEL | |
209 | int m_sumWheelRotation; | |
210 | #endif | |
211 | ||
212 | DECLARE_EVENT_TABLE() | |
213 | DECLARE_NO_COPY_CLASS(wxVScrolledWindow) | |
214 | DECLARE_ABSTRACT_CLASS(wxVScrolledWindow) | |
215 | }; | |
216 | ||
217 | #endif // _WX_VSCROLL_H_ | |
218 |