]> git.saurik.com Git - wxWidgets.git/blame_incremental - src/msw/dcclient.cpp
Added a file
[wxWidgets.git] / src / msw / dcclient.cpp
... / ...
CommitLineData
1/////////////////////////////////////////////////////////////////////////////
2// Name: dcclient.cpp
3// Purpose: wxClientDC class
4// Author: Julian Smart
5// Modified by:
6// Created: 01/02/97
7// RCS-ID: $Id$
8// Copyright: (c) Julian Smart and Markus Holzem
9// Licence: wxWindows licence
10/////////////////////////////////////////////////////////////////////////////
11
12// ===========================================================================
13// declarations
14// ===========================================================================
15
16// ----------------------------------------------------------------------------
17// headers
18// ----------------------------------------------------------------------------
19
20#ifdef __GNUG__
21 #pragma implementation "dcclient.h"
22#endif
23
24// For compilers that support precompilation, includes "wx.h".
25#include "wx/wxprec.h"
26
27#ifdef __BORLANDC__
28 #pragma hdrstop
29#endif
30
31#include "wx/string.h"
32#include "wx/log.h"
33#include "wx/window.h"
34
35#include "wx/msw/private.h"
36
37#include "wx/dcclient.h"
38
39// ----------------------------------------------------------------------------
40// array/list types
41// ----------------------------------------------------------------------------
42
43struct WXDLLEXPORT wxPaintDCInfo
44{
45 wxPaintDCInfo(wxWindow *win, wxDC *dc)
46 {
47 hwnd = win->GetHWND();
48 hdc = dc->GetHDC();
49 count = 1;
50 }
51
52 WXHWND hwnd; // window for this DC
53 WXHDC hdc; // the DC handle
54 size_t count; // usage count
55};
56
57#include "wx/arrimpl.cpp"
58
59WX_DEFINE_OBJARRAY(wxArrayDCInfo);
60
61// ----------------------------------------------------------------------------
62// macros
63// ----------------------------------------------------------------------------
64
65IMPLEMENT_DYNAMIC_CLASS(wxWindowDC, wxDC)
66IMPLEMENT_DYNAMIC_CLASS(wxClientDC, wxWindowDC)
67IMPLEMENT_DYNAMIC_CLASS(wxPaintDC, wxClientDC)
68
69// ----------------------------------------------------------------------------
70// global variables
71// ----------------------------------------------------------------------------
72
73static PAINTSTRUCT g_paintStruct;
74
75#ifdef __WXDEBUG__
76 // a global variable which we check to verify that wxPaintDC are only
77 // created in resopnse to WM_PAINT message - doing this from elsewhere is a
78 // common programming error among wxWindows programmers and might lead to
79 // very subtle and difficult to debug refresh/repaint bugs.
80 int g_isPainting = 0;
81#endif // __WXDEBUG__
82
83// ===========================================================================
84// implementation
85// ===========================================================================
86
87// ----------------------------------------------------------------------------
88// wxWindowDC
89// ----------------------------------------------------------------------------
90
91wxWindowDC::wxWindowDC()
92{
93 m_canvas = NULL;
94}
95
96wxWindowDC::wxWindowDC(wxWindow *canvas)
97{
98 wxCHECK_RET( canvas, _T("invalid window in wxWindowDC") );
99
100 m_canvas = canvas;
101 m_hDC = (WXHDC) ::GetWindowDC(GetHwndOf(m_canvas));
102
103 // m_bOwnsDC was already set to false in the base class ctor, so the DC
104 // will be released (and not deleted) in ~wxDC
105 InitDC();
106}
107
108void wxWindowDC::InitDC()
109{
110 // the background mode is only used for text background and is set in
111 // DrawText() to OPAQUE as required, otherwise always TRANSPARENT,
112 ::SetBkMode(GetHdc(), TRANSPARENT);
113
114 // default bg colour is pne of the window
115 SetBackground(wxBrush(m_canvas->GetBackgroundColour(), wxSOLID));
116}
117
118// ----------------------------------------------------------------------------
119// wxClientDC
120// ----------------------------------------------------------------------------
121
122wxClientDC::wxClientDC()
123{
124 m_canvas = NULL;
125}
126
127wxClientDC::wxClientDC(wxWindow *canvas)
128{
129 wxCHECK_RET( canvas, _T("invalid window in wxClientDC") );
130
131 m_canvas = canvas;
132 m_hDC = (WXHDC)::GetDC(GetHwndOf(m_canvas));
133
134 // m_bOwnsDC was already set to false in the base class ctor, so the DC
135 // will be released (and not deleted) in ~wxDC
136
137 InitDC();
138}
139
140void wxClientDC::InitDC()
141{
142 wxWindowDC::InitDC();
143
144 // in wxUniv build we must manually do some DC adjustments usually
145 // performed by Windows for us
146#ifdef __WXUNIVERSAL__
147 wxPoint ptOrigin = m_canvas->GetClientAreaOrigin();
148 if ( ptOrigin.x || ptOrigin.y )
149 {
150 // no need to shift DC origin if shift is null
151 SetDeviceOrigin(ptOrigin.x, ptOrigin.y);
152 }
153
154 // clip the DC to avoid overwriting the non client area
155 SetClippingRegion(wxPoint(0, 0), m_canvas->GetClientSize());
156#endif // __WXUNIVERSAL__
157}
158
159wxClientDC::~wxClientDC()
160{
161}
162
163// ----------------------------------------------------------------------------
164// wxPaintDC
165// ----------------------------------------------------------------------------
166
167// VZ: initial implementation (by JACS) only remembered the last wxPaintDC
168// created and tried to reuse it - this was supposed to take care of a
169// situation when a derived class OnPaint() calls base class OnPaint()
170// because in this case ::BeginPaint() shouldn't be called second time.
171//
172// I'm not sure how useful this is, however we must remember the HWND
173// associated with the last HDC as well - otherwise we may (and will!) try
174// to reuse the HDC for another HWND which is a nice recipe for disaster.
175//
176// So we store a list of windows for which we already have the DC and not
177// just one single hDC. This seems to work, but I'm really not sure about
178// the usefullness of the whole idea - IMHO it's much better to not call
179// base class OnPaint() at all, or, if we really want to allow it, add a
180// "wxPaintDC *" parameter to wxPaintEvent which should be used if it's
181// !NULL instead of creating a new DC.
182
183wxArrayDCInfo wxPaintDC::ms_cache;
184
185wxPaintDC::wxPaintDC()
186{
187 m_canvas = NULL;
188}
189
190wxPaintDC::wxPaintDC(wxWindow *canvas)
191{
192 wxCHECK_RET( canvas, wxT("NULL canvas in wxPaintDC ctor") );
193
194#ifdef __WXDEBUG__
195 if ( g_isPainting <= 0 )
196 {
197 wxFAIL_MSG( wxT("wxPaintDC may be created only in EVT_PAINT handler!") );
198
199 return;
200 }
201#endif // __WXDEBUG__
202
203 m_canvas = canvas;
204
205 // do we have a DC for this window in the cache?
206 wxPaintDCInfo *info = FindInCache();
207 if ( info )
208 {
209 m_hDC = info->hdc;
210 info->count++;
211 }
212 else // not in cache, create a new one
213 {
214 m_hDC = (WXHDC)::BeginPaint(GetHwndOf(m_canvas), &g_paintStruct);
215 if (m_hDC)
216 ms_cache.Add(new wxPaintDCInfo(m_canvas, this));
217 }
218
219 // (re)set the DC parameters.
220 // Note: at this point m_hDC can be NULL under MicroWindows, when dragging.
221 if (GetHDC())
222 InitDC();
223}
224
225wxPaintDC::~wxPaintDC()
226{
227 if ( m_hDC )
228 {
229 SelectOldObjects(m_hDC);
230
231 size_t index;
232 wxPaintDCInfo *info = FindInCache(&index);
233
234 wxCHECK_RET( info, wxT("existing DC should have a cache entry") );
235
236 if ( !--info->count )
237 {
238 ::EndPaint(GetHwndOf(m_canvas), &g_paintStruct);
239
240 ms_cache.Remove(index);
241
242 // Reduce the number of bogus reports of non-freed memory
243 // at app exit
244 if (ms_cache.IsEmpty())
245 ms_cache.Clear();
246 }
247 //else: cached DC entry is still in use
248
249 // prevent the base class dtor from ReleaseDC()ing it again
250 m_hDC = 0;
251 }
252}
253
254wxPaintDCInfo *wxPaintDC::FindInCache(size_t *index) const
255{
256 wxPaintDCInfo *info = NULL;
257 size_t nCache = ms_cache.GetCount();
258 for ( size_t n = 0; n < nCache; n++ )
259 {
260 info = &ms_cache[n];
261 if ( info->hwnd == m_canvas->GetHWND() )
262 {
263 if ( index )
264 *index = n;
265 break;
266 }
267 }
268
269 return info;
270}
271
272// find the entry for this DC in the cache (keyed by the window)
273WXHDC wxPaintDC::FindDCInCache(wxWindow* win)
274{
275 wxPaintDCInfo *info = NULL;
276 size_t nCache = ms_cache.GetCount();
277 for ( size_t n = 0; n < nCache; n++ )
278 {
279 info = &ms_cache[n];
280 if ( info->hwnd == win->GetHWND() )
281 {
282 return info->hdc;
283 }
284 }
285 return 0;
286}
287