src/msw/button.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        msw/button.cpp
   3 // Purpose:     wxButton
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     04/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Julian Smart and Markus Holzem
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #ifdef __GNUG__
  21     #pragma implementation "button.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 #if wxUSE_BUTTON
  32
  33 #ifndef WX_PRECOMP
  34     #include "wx/button.h"
  35     #include "wx/brush.h"
  36     #include "wx/panel.h"
  37     #include "wx/bmpbuttn.h"
  38     #include "wx/settings.h"
  39     #include "wx/dcscreen.h"
  40 #endif
  41
  42 #include "wx/msw/private.h"
  43
  44 // ----------------------------------------------------------------------------
  45 // macros
  46 // ----------------------------------------------------------------------------
  47
  48 IMPLEMENT_DYNAMIC_CLASS(wxButton, wxControl)
  49
  50 // this macro tries to adjust the default button height to a reasonable value
  51 // using the char height as the base
  52 #define BUTTON_HEIGHT_FROM_CHAR_HEIGHT(cy) (11*EDIT_HEIGHT_FROM_CHAR_HEIGHT(cy)/10)
  53
  54 // ============================================================================
  55 // implementation
  56 // ============================================================================
  57
  58 // ----------------------------------------------------------------------------
  59 // creation/destruction
  60 // ----------------------------------------------------------------------------
  61
  62 bool wxButton::Create(wxWindow *parent,
  63                       wxWindowID id,
  64                       const wxString& label,
  65                       const wxPoint& pos,
  66                       const wxSize& size,
  67                       long style,
  68                       const wxValidator& validator,
  69                       const wxString& name)
  70 {
  71     if ( !CreateControl(parent, id, pos, size, style, validator, name) )
  72         return FALSE;
  73
  74     WXDWORD exstyle;
  75     WXDWORD msStyle = MSWGetStyle(style, &exstyle);
  76
  77 #ifdef __WIN32__
  78     // if the label contains several lines we must explicitly tell the button
  79     // about it or it wouldn't draw it correctly ("\n"s would just appear as
  80     // black boxes)
  81     //
  82     // NB: we do it here and not in MSWGetStyle() because we need the label
  83     //     value and m_label is not set yet when MSWGetStyle() is called;
  84     //     besides changing BS_MULTILINE during run-time is pointless anyhow
  85     if ( label.find(_T('\n')) != wxString::npos )
  86     {
  87         msStyle |= BS_MULTILINE;
  88     }
  89 #endif // __WIN32__
  90
  91     return MSWCreateControl(_T("BUTTON"), msStyle, pos, size, label, exstyle);
  92 }
  93
  94 wxButton::~wxButton()
  95 {
  96 }
  97
  98 // ----------------------------------------------------------------------------
  99 // flags
 100 // ----------------------------------------------------------------------------
 101
 102 WXDWORD wxButton::MSWGetStyle(long style, WXDWORD *exstyle) const
 103 {
 104     // buttons never have an external border, they draw their own one
 105     WXDWORD msStyle = wxControl::MSWGetStyle
 106                       (
 107                         (style & ~wxBORDER_MASK) | wxBORDER_NONE, exstyle
 108                       );
 109
 110     // we must use WS_CLIPSIBLINGS with the buttons or they would draw over
 111     // each other in any resizeable dialog which has more than one button in
 112     // the bottom
 113     msStyle |= WS_CLIPSIBLINGS;
 114
 115 #ifdef __WIN32__
 116     // don't use "else if" here: weird as it is, but you may combine wxBU_LEFT
 117     // and wxBU_RIGHT to get BS_CENTER!
 118     if ( style & wxBU_LEFT )
 119         msStyle |= BS_LEFT;
 120     if ( style & wxBU_RIGHT )
 121         msStyle |= BS_RIGHT;
 122     if ( style & wxBU_TOP )
 123         msStyle |= BS_TOP;
 124     if ( style & wxBU_BOTTOM )
 125         msStyle |= BS_BOTTOM;
 126 #endif // __WIN32__
 127
 128     return msStyle;
 129 }
 130
 131 // ----------------------------------------------------------------------------
 132 // size management including autosizing
 133 // ----------------------------------------------------------------------------
 134
 135 wxSize wxButton::DoGetBestSize() const
 136 {
 137     wxString label = wxGetWindowText(GetHWND());
 138     int wBtn;
 139     GetTextExtent(label, &wBtn, NULL);
 140
 141     int wChar, hChar;
 142     wxGetCharSize(GetHWND(), &wChar, &hChar, &GetFont());
 143
 144     // add a margin - the button is wider than just its label
 145     wBtn += 3*wChar;
 146
 147     // the button height is proportional to the height of the font used
 148     int hBtn = BUTTON_HEIGHT_FROM_CHAR_HEIGHT(hChar);
 149
 150     wxSize sz = GetDefaultSize();
 151     if (wBtn > sz.x) sz.x = wBtn;
 152     if (hBtn > sz.y) sz.y = hBtn;
 153
 154     return sz;
 155 }
 156
 157 /* static */
 158 wxSize wxButtonBase::GetDefaultSize()
 159 {
 160     static wxSize s_sizeBtn;
 161
 162     if ( s_sizeBtn.x == 0 )
 163     {
 164         wxScreenDC dc;
 165         dc.SetFont(wxSystemSettings::GetFont(wxSYS_DEFAULT_GUI_FONT));
 166
 167         // the size of a standard button in the dialog units is 50x14,
 168         // translate this to pixels
 169         // NB1: the multipliers come from the Windows convention
 170         // NB2: the extra +1/+2 were needed to get the size be the same as the
 171         //      size of the buttons in the standard dialog - I don't know how
 172         //      this happens, but on my system this size is 75x23 in pixels and
 173         //      23*8 isn't even divisible by 14... Would be nice to understand
 174         //      why these constants are needed though!
 175         s_sizeBtn.x = (50 * (dc.GetCharWidth() + 1))/4;
 176         s_sizeBtn.y = ((14 * dc.GetCharHeight()) + 2)/8;
 177     }
 178
 179     return s_sizeBtn;
 180 }
 181
 182 // ----------------------------------------------------------------------------
 183 // default button handling
 184 // ----------------------------------------------------------------------------
 185
 186 /*
 187    "Everything you ever wanted to know about the default buttons" or "Why do we
 188    have to do all this?"
 189
 190    In MSW the default button should be activated when the user presses Enter
 191    and the current control doesn't process Enter itself somehow. This is
 192    handled by ::DefWindowProc() (or maybe ::DefDialogProc()) using DM_SETDEFID
 193    Another aspect of "defaultness" is that the default button has different
 194    appearance: this is due to BS_DEFPUSHBUTTON style which is completely
 195    separate from DM_SETDEFID stuff (!).
 196
 197    Final complication is that when a button is active, it should be the default
 198    one, i.e. pressing Enter on a button always activates it and not another
 199    one.
 200
 201    We handle this by maintaining a permanent and a temporary default items in
 202    wxControlContainer (both may be NULL). When a button becomes the current
 203    control (i.e. gets focus) it sets itself as the temporary default which
 204    ensures that it has the right appearance and that Enter will be redirected
 205    to it. When the button loses focus, it unsets the temporary default and so
 206    the default item will be the permanent default -- that is the default button
 207    if any had been set or none otherwise, which is just what we want.
 208
 209    Remark that we probably don't need to send DM_SETDEFID as we don't use
 210    ::IsDialogMessage() (which relies on it) any longer but OTOH it probably
 211    doesn't hurt neither.
 212  */
 213
 214 // set this button as the (permanently) default one in its panel
 215 void wxButton::SetDefault()
 216 {
 217     wxWindow *parent = GetParent();
 218
 219     wxCHECK_RET( parent, _T("button without parent?") );
 220
 221     // set this one as the default button both for wxWindows and Windows
 222     wxWindow *winOldDefault = parent->SetDefaultItem(this);
 223     ::SendMessage(GetWinHwnd(parent), DM_SETDEFID, m_windowId, 0L);
 224
 225     UpdateDefaultStyle(this, winOldDefault);
 226 }
 227
 228 void wxButton::SetTmpDefault()
 229 {
 230     wxWindow *parent = GetParent();
 231
 232     wxCHECK_RET( parent, _T("button without parent?") );
 233
 234     wxWindow *winOldDefault = parent->GetDefaultItem();
 235     parent->SetTmpDefaultItem(this);
 236     if ( winOldDefault != this )
 237     {
 238         UpdateDefaultStyle(this, winOldDefault);
 239     }
 240     //else: no styles to update
 241 }
 242
 243 void wxButton::UnsetTmpDefault()
 244 {
 245     wxWindow *parent = GetParent();
 246
 247     wxCHECK_RET( parent, _T("button without parent?") );
 248
 249     parent->SetTmpDefaultItem(NULL);
 250
 251     wxWindow *winOldDefault = parent->GetDefaultItem();
 252     if ( winOldDefault != this )
 253     {
 254         UpdateDefaultStyle(winOldDefault, this);
 255     }
 256     //else: we had been default before anyhow
 257 }
 258
 259 /* static */
 260 void
 261 wxButton::UpdateDefaultStyle(wxWindow *winDefault, wxWindow *winOldDefault)
 262 {
 263     // clear the BS_DEFPUSHBUTTON for the old default button
 264     wxButton *btnOldDefault = wxDynamicCast(winOldDefault, wxButton);
 265     if ( btnOldDefault && btnOldDefault != winDefault )
 266     {
 267         // remove the BS_DEFPUSHBUTTON style from the other button
 268         long style = ::GetWindowLong(GetHwndOf(btnOldDefault), GWL_STYLE);
 269
 270         // don't do it with the owner drawn buttons because it will reset
 271         // BS_OWNERDRAW style bit too (BS_OWNERDRAW & BS_DEFPUSHBUTTON != 0)!
 272         if ( (style & BS_OWNERDRAW) != BS_OWNERDRAW )
 273         {
 274             style &= ~BS_DEFPUSHBUTTON;
 275             ::SendMessage(GetHwndOf(btnOldDefault), BM_SETSTYLE, style, 1L);
 276         }
 277         else
 278         {
 279             // redraw the button - it will notice itself that it's not the
 280             // default one any longer
 281             btnOldDefault->Refresh();
 282         }
 283     }
 284
 285     // and set BS_DEFPUSHBUTTON for this button
 286     wxButton *btnDefault = wxDynamicCast(winDefault, wxButton);
 287     if ( btnDefault )
 288     {
 289         long style = ::GetWindowLong(GetHwndOf(btnDefault), GWL_STYLE);
 290         if ( (style & BS_OWNERDRAW) != BS_OWNERDRAW )
 291         {
 292             style |= BS_DEFPUSHBUTTON;
 293             ::SendMessage(GetHwndOf(btnDefault), BM_SETSTYLE, style, 1L);
 294         }
 295         else
 296         {
 297             btnDefault->Refresh();
 298         }
 299     }
 300 }
 301
 302 // ----------------------------------------------------------------------------
 303 // helpers
 304 // ----------------------------------------------------------------------------
 305
 306 bool wxButton::SendClickEvent()
 307 {
 308     wxCommandEvent event(wxEVT_COMMAND_BUTTON_CLICKED, GetId());
 309     event.SetEventObject(this);
 310
 311     return ProcessCommand(event);
 312 }
 313
 314 void wxButton::Command(wxCommandEvent & event)
 315 {
 316     ProcessCommand(event);
 317 }
 318
 319 // ----------------------------------------------------------------------------
 320 // event/message handlers
 321 // ----------------------------------------------------------------------------
 322
 323 bool wxButton::MSWCommand(WXUINT param, WXWORD WXUNUSED(id))
 324 {
 325     bool processed = FALSE;
 326     switch ( param )
 327     {
 328         case 1:                     // message came from an accelerator
 329         case BN_CLICKED:            // normal buttons send this
 330         case BN_DOUBLECLICKED:      // owner-drawn ones also send this
 331             processed = SendClickEvent();
 332             break;
 333     }
 334
 335     return processed;
 336 }
 337
 338 long wxButton::MSWWindowProc(WXUINT nMsg, WXWPARAM wParam, WXLPARAM lParam)
 339 {
 340     // when we receive focus, we want to temporary become the default button in
 341     // our parent panel so that pressing "Enter" would activate us -- and when
 342     // losing it we should restore the previous default button as well
 343     if ( nMsg == WM_SETFOCUS )
 344     {
 345         SetTmpDefault();
 346
 347         // let the default processing take place too
 348     }
 349     else if ( nMsg == WM_KILLFOCUS )
 350     {
 351         UnsetTmpDefault();
 352     }
 353     else if ( nMsg == WM_LBUTTONDBLCLK )
 354     {
 355         // emulate a click event to force an owner-drawn button to change its
 356         // appearance - without this, it won't do it
 357         (void)wxControl::MSWWindowProc(WM_LBUTTONDOWN, wParam, lParam);
 358
 359         // and continue with processing the message normally as well
 360     }
 361
 362     // let the base class do all real processing
 363     return wxControl::MSWWindowProc(nMsg, wParam, lParam);
 364 }
 365
 366 // ----------------------------------------------------------------------------
 367 // owner-drawn buttons support
 368 // ----------------------------------------------------------------------------
 369
 370 #ifdef __WIN32__
 371
 372 // drawing helpers
 373
 374 static void DrawButtonText(HDC hdc,
 375                            RECT *pRect,
 376                            const wxString& text,
 377                            COLORREF col)
 378 {
 379     COLORREF colOld = SetTextColor(hdc, col);
 380     int modeOld = SetBkMode(hdc, TRANSPARENT);
 381
 382     DrawText(hdc, text, text.length(), pRect,
 383              DT_CENTER | DT_VCENTER | DT_SINGLELINE);
 384
 385     SetBkMode(hdc, modeOld);
 386     SetTextColor(hdc, colOld);
 387 }
 388
 389 static void DrawRect(HDC hdc, const RECT& r)
 390 {
 391     MoveToEx(hdc, r.left, r.top, NULL);
 392     LineTo(hdc, r.right, r.top);
 393     LineTo(hdc, r.right, r.bottom);
 394     LineTo(hdc, r.left, r.bottom);
 395     LineTo(hdc, r.left, r.top);
 396 }
 397
 398 void wxButton::MakeOwnerDrawn()
 399 {
 400     long style = GetWindowLong(GetHwnd(), GWL_STYLE);
 401     if ( (style & BS_OWNERDRAW) != BS_OWNERDRAW )
 402     {
 403         // make it so
 404         style |= BS_OWNERDRAW;
 405         SetWindowLong(GetHwnd(), GWL_STYLE, style);
 406     }
 407 }
 408
 409 bool wxButton::SetBackgroundColour(const wxColour &colour)
 410 {
 411     if ( !wxControl::SetBackgroundColour(colour) )
 412     {
 413         // nothing to do
 414         return FALSE;
 415     }
 416
 417     MakeOwnerDrawn();
 418
 419     Refresh();
 420
 421     return TRUE;
 422 }
 423
 424 bool wxButton::SetForegroundColour(const wxColour &colour)
 425 {
 426     if ( !wxControl::SetForegroundColour(colour) )
 427     {
 428         // nothing to do
 429         return FALSE;
 430     }
 431
 432     MakeOwnerDrawn();
 433
 434     Refresh();
 435
 436     return TRUE;
 437 }
 438
 439 /*
 440    The button frame looks like this normally:
 441
 442    WWWWWWWWWWWWWWWWWWB
 443    WHHHHHHHHHHHHHHHHGB  W = white       (HILIGHT)
 444    WH               GB  H = light grey  (LIGHT)
 445    WH               GB  G = dark grey   (SHADOW)
 446    WH               GB  B = black       (DKSHADOW)
 447    WH               GB
 448    WGGGGGGGGGGGGGGGGGB
 449    BBBBBBBBBBBBBBBBBBB
 450
 451    When the button is selected, the button becomes like this (the total button
 452    size doesn't change):
 453
 454    BBBBBBBBBBBBBBBBBBB
 455    BWWWWWWWWWWWWWWWWBB
 456    BWHHHHHHHHHHHHHHGBB
 457    BWH             GBB
 458    BWH             GBB
 459    BWGGGGGGGGGGGGGGGBB
 460    BBBBBBBBBBBBBBBBBBB
 461    BBBBBBBBBBBBBBBBBBB
 462
 463    When the button is pushed (while selected) it is like:
 464
 465    BBBBBBBBBBBBBBBBBBB
 466    BGGGGGGGGGGGGGGGGGB
 467    BG               GB
 468    BG               GB
 469    BG               GB
 470    BG               GB
 471    BGGGGGGGGGGGGGGGGGB
 472    BBBBBBBBBBBBBBBBBBB
 473 */
 474
 475 static void DrawButtonFrame(HDC hdc, const RECT& rectBtn,
 476                             bool selected, bool pushed)
 477 {
 478     RECT r;
 479     CopyRect(&r, &rectBtn);
 480
 481     HPEN hpenBlack   = CreatePen(PS_SOLID, 1, GetSysColor(COLOR_3DDKSHADOW)),
 482          hpenGrey    = CreatePen(PS_SOLID, 1, GetSysColor(COLOR_3DSHADOW)),
 483          hpenLightGr = CreatePen(PS_SOLID, 1, GetSysColor(COLOR_3DLIGHT)),
 484          hpenWhite   = CreatePen(PS_SOLID, 1, GetSysColor(COLOR_3DHILIGHT));
 485
 486     HPEN hpenOld = (HPEN)SelectObject(hdc, hpenBlack);
 487
 488     r.right--;
 489     r.bottom--;
 490
 491     if ( pushed )
 492     {
 493         DrawRect(hdc, r);
 494
 495         (void)SelectObject(hdc, hpenGrey);
 496         InflateRect(&r, -1, -1);
 497
 498         DrawRect(hdc, r);
 499     }
 500     else // !pushed
 501     {
 502         if ( selected )
 503         {
 504             DrawRect(hdc, r);
 505
 506             InflateRect(&r, -1, -1);
 507         }
 508
 509         MoveToEx(hdc, r.left, r.bottom, NULL);
 510         LineTo(hdc, r.right, r.bottom);
 511         LineTo(hdc, r.right, r.top - 1);
 512
 513         (void)SelectObject(hdc, hpenWhite);
 514         MoveToEx(hdc, r.left, r.bottom - 1, NULL);
 515         LineTo(hdc, r.left, r.top);
 516         LineTo(hdc, r.right, r.top);
 517
 518         (void)SelectObject(hdc, hpenLightGr);
 519         MoveToEx(hdc, r.left + 1, r.bottom - 2, NULL);
 520         LineTo(hdc, r.left + 1, r.top + 1);
 521         LineTo(hdc, r.right - 1, r.top + 1);
 522
 523         (void)SelectObject(hdc, hpenGrey);
 524         MoveToEx(hdc, r.left + 1, r.bottom - 1, NULL);
 525         LineTo(hdc, r.right - 1, r.bottom - 1);
 526         LineTo(hdc, r.right - 1, r.top);
 527     }
 528
 529     (void)SelectObject(hdc, hpenOld);
 530     DeleteObject(hpenWhite);
 531     DeleteObject(hpenLightGr);
 532     DeleteObject(hpenGrey);
 533     DeleteObject(hpenBlack);
 534 }
 535
 536 bool wxButton::MSWOnDraw(WXDRAWITEMSTRUCT *wxdis)
 537 {
 538     LPDRAWITEMSTRUCT lpDIS = (LPDRAWITEMSTRUCT)wxdis;
 539
 540     RECT rectBtn;
 541     CopyRect(&rectBtn, &lpDIS->rcItem);
 542
 543     COLORREF colBg = wxColourToRGB(GetBackgroundColour()),
 544              colFg = wxColourToRGB(GetForegroundColour());
 545
 546     HDC hdc = lpDIS->hDC;
 547     UINT state = lpDIS->itemState;
 548
 549     // first, draw the background
 550     HBRUSH hbrushBackground = ::CreateSolidBrush(colBg);
 551
 552     FillRect(hdc, &rectBtn, hbrushBackground);
 553
 554     // draw the border for the current state
 555     bool selected = (state & ODS_SELECTED) != 0;
 556     if ( !selected )
 557     {
 558         wxPanel *panel = wxDynamicCast(GetParent(), wxPanel);
 559         if ( panel )
 560         {
 561             selected = panel->GetDefaultItem() == this;
 562         }
 563     }
 564     bool pushed = (SendMessage(GetHwnd(), BM_GETSTATE, 0, 0) & BST_PUSHED) != 0;
 565
 566     DrawButtonFrame(hdc, rectBtn, selected, pushed);
 567
 568     // draw the focus rect if needed
 569     if ( state & ODS_FOCUS )
 570     {
 571         RECT rectFocus;
 572         CopyRect(&rectFocus, &rectBtn);
 573
 574         // I don't know where does this constant come from, but this is how
 575         // Windows draws them
 576         InflateRect(&rectFocus, -4, -4);
 577
 578         DrawFocusRect(hdc, &rectFocus);
 579     }
 580
 581     if ( pushed )
 582     {
 583         // the label is shifted by 1 pixel to create "pushed" effect
 584         OffsetRect(&rectBtn, 1, 1);
 585     }
 586
 587     DrawButtonText(hdc, &rectBtn, GetLabel(),
 588                    state & ODS_DISABLED ? GetSysColor(COLOR_GRAYTEXT)
 589                                         : colFg);
 590
 591     ::DeleteObject(hbrushBackground);
 592
 593     return TRUE;
 594 }
 595
 596 #endif // __WIN32__
 597
 598 #endif // wxUSE_BUTTON
 599