changing the number of items in wxHtmlListBox should flush the cache
[wxWidgets.git] / src / generic / htmllbox.cpp
1 ///////////////////////////////////////////////////////////////////////////////
2 // Name: generic/htmllbox.cpp
3 // Purpose: implementation of wxHtmlListBox
4 // Author: Vadim Zeitlin
5 // Modified by:
6 // Created: 31.05.03
7 // RCS-ID: $Id$
8 // Copyright: (c) 2003 Vadim Zeitlin <vadim@wxwindows.org>
9 // License: wxWindows license
10 ///////////////////////////////////////////////////////////////////////////////
11
12 // ============================================================================
13 // declarations
14 // ============================================================================
15
16 // ----------------------------------------------------------------------------
17 // headers
18 // ----------------------------------------------------------------------------
19
20 // For compilers that support precompilation, includes "wx.h".
21 #include "wx/wxprec.h"
22
23 #ifdef __BORLANDC__
24 #pragma hdrstop
25 #endif
26
27 #ifndef WX_PRECOMP
28 #include "wx/dcclient.h"
29 #endif //WX_PRECOMP
30
31 #include "wx/htmllbox.h"
32
33 #include "wx/html/htmlcell.h"
34 #include "wx/html/winpars.h"
35
36 // this hack forces the linker to always link in m_* files
37 #include "wx/html/forcelnk.h"
38 FORCE_WXHTML_MODULES()
39
40 // ============================================================================
41 // private classes
42 // ============================================================================
43
44 // ----------------------------------------------------------------------------
45 // wxHtmlListBoxCache
46 // ----------------------------------------------------------------------------
47
48 // this class is used by wxHtmlListBox to cache the parsed representation of
49 // the items to avoid doing it anew each time an item must be drawn
50 class wxHtmlListBoxCache
51 {
52 public:
53 wxHtmlListBoxCache()
54 {
55 for ( size_t n = 0; n < SIZE; n++ )
56 {
57 m_items[n] = (size_t)-1;
58 m_cells[n] = NULL;
59 }
60
61 m_next = 0;
62 }
63
64 ~wxHtmlListBoxCache()
65 {
66 for ( size_t n = 0; n < SIZE; n++ )
67 {
68 delete m_cells[n];
69 }
70 }
71
72 // completely invalidate the cache
73 void Clear()
74 {
75 for ( size_t n = 0; n < SIZE; n++ )
76 {
77 m_items[n] = (size_t)-1;
78 delete m_cells[n];
79 m_cells[n] = NULL;
80 }
81 }
82
83 // return the cached cell for this index or NULL if none
84 wxHtmlCell *Get(size_t item) const
85 {
86 for ( size_t n = 0; n < SIZE; n++ )
87 {
88 if ( m_items[n] == item )
89 return m_cells[n];
90 }
91
92 return NULL;
93 }
94
95 // returns true if we already have this item cached
96 bool Has(size_t item) const { return Get(item) != NULL; }
97
98 // ensure that the item is cached
99 void Store(size_t item, wxHtmlCell *cell)
100 {
101 delete m_cells[m_next];
102 m_cells[m_next] = cell;
103 m_items[m_next] = item;
104
105 // advance to the next item wrapping around if there are no more
106 if ( ++m_next == SIZE )
107 m_next = 0;
108 }
109
110 private:
111 // the max number of the items we cache
112 enum { SIZE = 50 };
113
114 // the index of the LRU (oldest) cell
115 size_t m_next;
116
117 // the parsed representation of the cached item or NULL
118 wxHtmlCell *m_cells[SIZE];
119
120 // the index of the currently cached item (only valid if m_cells != NULL)
121 size_t m_items[SIZE];
122 };
123
124 // ----------------------------------------------------------------------------
125 // wxHtmlListBoxStyle
126 // ----------------------------------------------------------------------------
127
128 // just forward wxDefaultHtmlRenderingStyle callbacks to the main class so that
129 // they could be overridden by the user code
130 class wxHtmlListBoxStyle : public wxDefaultHtmlRenderingStyle
131 {
132 public:
133 wxHtmlListBoxStyle(wxHtmlListBox& hlbox) : m_hlbox(hlbox) { }
134
135 virtual wxColour GetSelectedTextColour(const wxColour& colFg)
136 {
137 return m_hlbox.GetSelectedTextColour(colFg);
138 }
139
140 virtual wxColour GetSelectedTextBgColour(const wxColour& colBg)
141 {
142 return m_hlbox.GetSelectedTextBgColour(colBg);
143 }
144
145 private:
146 const wxHtmlListBox& m_hlbox;
147 };
148
149
150 // ----------------------------------------------------------------------------
151 // event tables
152 // ----------------------------------------------------------------------------
153
154 BEGIN_EVENT_TABLE(wxHtmlListBox, wxVListBox)
155 EVT_SIZE(wxHtmlListBox::OnSize)
156 END_EVENT_TABLE()
157
158 // ============================================================================
159 // implementation
160 // ============================================================================
161
162 // ----------------------------------------------------------------------------
163 // wxHtmlListBox creation
164 // ----------------------------------------------------------------------------
165
166 void wxHtmlListBox::Init()
167 {
168 m_htmlParser = NULL;
169 m_htmlRendStyle = new wxHtmlListBoxStyle(*this);
170 m_cache = new wxHtmlListBoxCache;
171 }
172
173 bool wxHtmlListBox::Create(wxWindow *parent,
174 wxWindowID id,
175 const wxPoint& pos,
176 const wxSize& size,
177 long style,
178 const wxString& name)
179 {
180 return wxVListBox::Create(parent, id, pos, size, style, name);
181 }
182
183 wxHtmlListBox::~wxHtmlListBox()
184 {
185 delete m_cache;
186
187 if ( m_htmlParser )
188 {
189 delete m_htmlParser->GetDC();
190 delete m_htmlParser;
191 }
192
193 delete m_htmlRendStyle;
194 }
195
196 // ----------------------------------------------------------------------------
197 // wxHtmlListBox appearance
198 // ----------------------------------------------------------------------------
199
200 wxColour wxHtmlListBox::GetSelectedTextColour(const wxColour& colFg) const
201 {
202 return m_htmlRendStyle->
203 wxDefaultHtmlRenderingStyle::GetSelectedTextColour(colFg);
204 }
205
206 wxColour
207 wxHtmlListBox::GetSelectedTextBgColour(const wxColour& WXUNUSED(colBg)) const
208 {
209 return GetSelectionBackground();
210 }
211
212 // ----------------------------------------------------------------------------
213 // wxHtmlListBox items markup
214 // ----------------------------------------------------------------------------
215
216 wxString wxHtmlListBox::OnGetItemMarkup(size_t n) const
217 {
218 // we don't even need to wrap the value returned by OnGetItem() inside
219 // "<html><body>" and "</body></html>" because wxHTML can parse it even
220 // without these tags
221 return OnGetItem(n);
222 }
223
224 // ----------------------------------------------------------------------------
225 // wxHtmlListBox cache handling
226 // ----------------------------------------------------------------------------
227
228 void wxHtmlListBox::CacheItem(size_t n) const
229 {
230 if ( !m_cache->Has(n) )
231 {
232 if ( !m_htmlParser )
233 {
234 wxHtmlListBox *self = wxConstCast(this, wxHtmlListBox);
235
236 self->m_htmlParser = new wxHtmlWinParser;
237 m_htmlParser->SetDC(new wxClientDC(self));
238 }
239
240 wxHtmlContainerCell *cell = (wxHtmlContainerCell *)m_htmlParser->
241 Parse(OnGetItemMarkup(n));
242 wxCHECK_RET( cell, _T("wxHtmlParser::Parse() returned NULL?") );
243
244 cell->Layout(GetClientSize().x - 2*GetMargins().x);
245
246 m_cache->Store(n, cell);
247 }
248 }
249
250 void wxHtmlListBox::OnSize(wxSizeEvent& event)
251 {
252 // we need to relayout all the cached cells
253 m_cache->Clear();
254
255 event.Skip();
256 }
257
258 void wxHtmlListBox::RefreshAll()
259 {
260 m_cache->Clear();
261
262 wxVListBox::RefreshAll();
263 }
264
265 void wxHtmlListBox::SetItemCount(size_t count)
266 {
267 // the items are going to change, forget the old ones
268 m_cache->Clear();
269
270 wxVListBox::SetItemCount(count);
271 }
272
273 // ----------------------------------------------------------------------------
274 // wxHtmlListBox implementation of wxVListBox pure virtuals
275 // ----------------------------------------------------------------------------
276
277 void wxHtmlListBox::OnDrawItem(wxDC& dc, const wxRect& rect, size_t n) const
278 {
279 CacheItem(n);
280
281 wxHtmlCell *cell = m_cache->Get(n);
282 wxCHECK_RET( cell, _T("this cell should be cached!") );
283
284 wxHtmlRenderingInfo htmlRendInfo;
285
286 // draw the selected cell in selected state
287 if ( IsSelected(n) )
288 {
289 wxHtmlSelection htmlSel;
290 htmlSel.Set(wxPoint(0, 0), cell, wxPoint(INT_MAX, INT_MAX), cell);
291 htmlRendInfo.SetSelection(&htmlSel);
292 if ( m_htmlRendStyle )
293 htmlRendInfo.SetStyle(m_htmlRendStyle);
294 htmlRendInfo.GetState().SetSelectionState(wxHTML_SEL_IN);
295 }
296
297 // note that we can't stop drawing exactly at the window boundary as then
298 // even the visible cells part could be not drawn, so always draw the
299 // entire cell
300 cell->Draw(dc, rect.x, rect.y, 0, INT_MAX, htmlRendInfo);
301 }
302
303 wxCoord wxHtmlListBox::OnMeasureItem(size_t n) const
304 {
305 CacheItem(n);
306
307 wxHtmlCell *cell = m_cache->Get(n);
308 wxCHECK_MSG( cell, 0, _T("this cell should be cached!") );
309
310 return cell->GetHeight() + cell->GetDescent();
311 }
312