src/common/containr.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/containr.cpp
   3 // Purpose:     implementation of wxControlContainer
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     06.08.01
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2001 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
   9 // License:     wxWindows licence
  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/log.h"
  29     #include "wx/event.h"
  30     #include "wx/window.h"
  31     #include "wx/scrolbar.h"
  32     #include "wx/radiobut.h"
  33     #include "wx/containr.h"
  34 #endif //WX_PRECOMP
  35
  36 // trace mask for focus messages
  37 #define TRACE_FOCUS _T("focus")
  38
  39 // ============================================================================
  40 // implementation
  41 // ============================================================================
  42
  43 wxControlContainer::wxControlContainer(wxWindow *winParent)
  44 {
  45     m_winParent = winParent;
  46     m_winLastFocused = NULL;
  47     m_inSetFocus = false;
  48 }
  49
  50 bool wxControlContainer::AcceptsFocus() const
  51 {
  52     // if we're not shown or disabled, we can't accept focus
  53     if ( m_winParent->IsShown() && m_winParent->IsEnabled() )
  54     {
  55         // otherwise we can accept focus either if we have no children at all
  56         // (in this case we're probably not used as a container) or only when
  57         // at least one child will accept focus
  58         wxWindowList::compatibility_iterator node = m_winParent->GetChildren().GetFirst();
  59         if ( !node )
  60             return true;
  61
  62 #ifdef __WXMAC__
  63         // wxMac has eventually the two scrollbars as children, they don't count
  64         // as real children in the algorithm mentioned above
  65         bool hasRealChildren = false ;
  66 #endif
  67
  68         while ( node )
  69         {
  70             wxWindow *child = node->GetData();
  71             node = node->GetNext();
  72
  73 #ifdef __WXMAC__
  74             if ( m_winParent->MacIsWindowScrollbar( child ) )
  75                 continue;
  76             hasRealChildren = true ;
  77 #endif
  78             if ( child->AcceptsFocus() )
  79             {
  80                 return true;
  81             }
  82         }
  83
  84 #ifdef __WXMAC__
  85         if ( !hasRealChildren )
  86             return true ;
  87 #endif
  88     }
  89
  90     return false;
  91 }
  92
  93 void wxControlContainer::SetLastFocus(wxWindow *win)
  94 {
  95     // the panel itself should never get the focus at all but if it does happen
  96     // temporarily (as it seems to do under wxGTK), at the very least don't
  97     // forget our previous m_winLastFocused
  98     if ( win != m_winParent )
  99     {
 100         // if we're setting the focus
 101         if ( win )
 102         {
 103             // find the last _immediate_ child which got focus
 104             wxWindow *winParent = win;
 105             while ( winParent != m_winParent )
 106             {
 107                 win = winParent;
 108                 winParent = win->GetParent();
 109
 110                 // Yes, this can happen, though in a totally pathological case.
 111                 // like when detaching a menubar from a frame with a child
 112                 // which has pushed itself as an event handler for the menubar.
 113                 // (under wxGTK)
 114
 115                 wxASSERT_MSG( winParent,
 116                               _T("Setting last focus for a window that is not our child?") );
 117             }
 118         }
 119
 120         m_winLastFocused = win;
 121
 122         if ( win )
 123         {
 124             wxLogTrace(TRACE_FOCUS, _T("Set last focus to %s(%s)"),
 125                        win->GetClassInfo()->GetClassName(),
 126                        win->GetLabel().c_str());
 127         }
 128         else
 129         {
 130             wxLogTrace(TRACE_FOCUS, _T("No more last focus"));
 131         }
 132     }
 133
 134     // propagate the last focus upwards so that our parent can set focus back
 135     // to us if it loses it now and regains later
 136     wxWindow *parent = m_winParent->GetParent();
 137     if ( parent )
 138     {
 139         wxChildFocusEvent eventFocus(m_winParent);
 140         parent->GetEventHandler()->ProcessEvent(eventFocus);
 141     }
 142 }
 143
 144 // --------------------------------------------------------------------
 145 // The following four functions are used to find other radio buttons
 146 // within the same group. Used by wxSetFocusToChild on wxMSW
 147 // --------------------------------------------------------------------
 148
 149 #ifdef __WXMSW__
 150
 151 wxRadioButton* wxGetPreviousButtonInGroup(wxRadioButton *btn)
 152 {
 153     if ( btn->HasFlag(wxRB_GROUP) || btn->HasFlag(wxRB_SINGLE) )
 154         return NULL;
 155
 156     const wxWindowList& siblings = btn->GetParent()->GetChildren();
 157     wxWindowList::compatibility_iterator nodeThis = siblings.Find(btn);
 158     wxCHECK_MSG( nodeThis, NULL, _T("radio button not a child of its parent?") );
 159
 160     // Iterate over all previous siblings until we find the next radio button
 161     wxWindowList::compatibility_iterator nodeBefore = nodeThis->GetPrevious();
 162     wxRadioButton *prevBtn = 0;
 163     while (nodeBefore)
 164     {
 165         prevBtn = wxDynamicCast(nodeBefore->GetData(), wxRadioButton);
 166         if (prevBtn)
 167             break;
 168
 169         nodeBefore = nodeBefore->GetPrevious();
 170     }
 171
 172     if (!prevBtn || prevBtn->HasFlag(wxRB_SINGLE))
 173     {
 174         // no more buttons in group
 175         return NULL;
 176     }
 177
 178     return prevBtn;
 179 }
 180
 181 wxRadioButton* wxGetNextButtonInGroup(wxRadioButton *btn)
 182 {
 183     if (btn->HasFlag(wxRB_SINGLE))
 184         return NULL;
 185
 186     const wxWindowList& siblings = btn->GetParent()->GetChildren();
 187     wxWindowList::compatibility_iterator nodeThis = siblings.Find(btn);
 188     wxCHECK_MSG( nodeThis, NULL, _T("radio button not a child of its parent?") );
 189
 190     // Iterate over all previous siblings until we find the next radio button
 191     wxWindowList::compatibility_iterator nodeNext = nodeThis->GetNext();
 192     wxRadioButton *nextBtn = 0;
 193     while (nodeNext)
 194     {
 195         nextBtn = wxDynamicCast(nodeNext->GetData(), wxRadioButton);
 196         if (nextBtn)
 197             break;
 198
 199         nodeNext = nodeNext->GetNext();
 200     }
 201
 202     if ( !nextBtn || nextBtn->HasFlag(wxRB_GROUP) || nextBtn->HasFlag(wxRB_SINGLE) )
 203     {
 204         // no more buttons or the first button of the next group
 205         return NULL;
 206     }
 207
 208     return nextBtn;
 209 }
 210
 211 wxRadioButton* wxGetFirstButtonInGroup(wxRadioButton *btn)
 212 {
 213     while (true)
 214     {
 215         wxRadioButton* prevBtn = wxGetPreviousButtonInGroup(btn);
 216         if (!prevBtn)
 217             return btn;
 218
 219         btn = prevBtn;
 220     }
 221 }
 222
 223 wxRadioButton* wxGetLastButtonInGroup(wxRadioButton *btn)
 224 {
 225     while (true)
 226     {
 227         wxRadioButton* nextBtn = wxGetNextButtonInGroup(btn);
 228         if (!nextBtn)
 229             return btn;
 230
 231         btn = nextBtn;
 232     }
 233 }
 234
 235 wxRadioButton* wxGetSelectedButtonInGroup(wxRadioButton *btn)
 236 {
 237     // Find currently selected button
 238     if (btn->GetValue())
 239         return btn;
 240
 241     if (btn->HasFlag(wxRB_SINGLE))
 242         return NULL;
 243
 244     wxRadioButton *selBtn;
 245
 246     // First check all previous buttons
 247     for (selBtn = wxGetPreviousButtonInGroup(btn); selBtn; selBtn = wxGetPreviousButtonInGroup(selBtn))
 248         if (selBtn->GetValue())
 249             return selBtn;
 250
 251     // Now all following buttons
 252     for (selBtn = wxGetNextButtonInGroup(btn); selBtn; selBtn = wxGetNextButtonInGroup(selBtn))
 253         if (selBtn->GetValue())
 254             return selBtn;
 255
 256     return NULL;
 257 }
 258
 259 #endif // __WXMSW__
 260
 261 // ----------------------------------------------------------------------------
 262 // Keyboard handling - this is the place where the TAB traversal logic is
 263 // implemented. As this code is common to all ports, this ensures consistent
 264 // behaviour even if we don't specify how exactly the wxNavigationKeyEvent are
 265 // generated and this is done in platform specific code which also ensures that
 266 // we can follow the given platform standards.
 267 // ----------------------------------------------------------------------------
 268
 269 void wxControlContainer::HandleOnNavigationKey( wxNavigationKeyEvent& event )
 270 {
 271     wxWindow *parent = m_winParent->GetParent();
 272
 273     // the event is propagated downwards if the event emitter was our parent
 274     bool goingDown = event.GetEventObject() == parent;
 275
 276     const wxWindowList& children = m_winParent->GetChildren();
 277
 278     // if we have exactly one notebook-like child window (actually it could be
 279     // any window that returns true from its HasMultiplePages()), then
 280     // [Shift-]Ctrl-Tab and Ctrl-PageUp/Down keys should iterate over its pages
 281     // even if the focus is outside of the control because this is how the
 282     // standard MSW properties dialogs behave and we do it under other platforms
 283     // as well because it seems like a good idea -- but we can always put this
 284     // block inside "#ifdef __WXMSW__" if it's not suitable there
 285     if ( event.IsWindowChange() && !goingDown )
 286     {
 287         // check if we have a unique notebook-like child
 288         wxWindow *bookctrl = NULL;
 289         for ( wxWindowList::const_iterator i = children.begin(),
 290                                          end = children.end();
 291               i != end;
 292               ++i )
 293         {
 294             wxWindow * const window = *i;
 295             if ( window->HasMultiplePages() )
 296             {
 297                 if ( bookctrl )
 298                 {
 299                     // this is the second book-like control already so don't do
 300                     // anything as we don't know which one should have its page
 301                     // changed
 302                     bookctrl = NULL;
 303                     break;
 304                 }
 305
 306                 bookctrl = window;
 307             }
 308         }
 309
 310         if ( bookctrl )
 311         {
 312             // make sure that we don't bubble up the event again from the book
 313             // control resulting in infinite recursion
 314             wxNavigationKeyEvent eventCopy(event);
 315             eventCopy.SetEventObject(m_winParent);
 316             if ( bookctrl->GetEventHandler()->ProcessEvent(eventCopy) )
 317                 return;
 318         }
 319     }
 320
 321     // there is not much to do if we don't have children and we're not
 322     // interested in "notebook page change" events here
 323     if ( !children.GetCount() || event.IsWindowChange() )
 324     {
 325         // let the parent process it unless it already comes from our parent
 326         // of we don't have any
 327         if ( goingDown ||
 328              !parent || !parent->GetEventHandler()->ProcessEvent(event) )
 329         {
 330             event.Skip();
 331         }
 332
 333         return;
 334     }
 335
 336     // where are we going?
 337     const bool forward = event.GetDirection();
 338
 339     // the node of the children list from which we should start looking for the
 340     // next acceptable child
 341     wxWindowList::compatibility_iterator node, start_node;
 342
 343     // we should start from the first/last control and not from the one which
 344     // had focus the last time if we're propagating the event downwards because
 345     // for our parent we look like a single control
 346     if ( goingDown )
 347     {
 348         // just to be sure it's not used (normally this is not necessary, but
 349         // doesn't hurt neither)
 350         m_winLastFocused = (wxWindow *)NULL;
 351
 352         // start from first or last depending on where we're going
 353         node = forward ? children.GetFirst() : children.GetLast();
 354     }
 355     else // going up
 356     {
 357         // try to find the child which has the focus currently
 358
 359         // the event emitter might have done this for us
 360         wxWindow *winFocus = event.GetCurrentFocus();
 361
 362         // but if not, we might know where the focus was ourselves
 363         if (!winFocus)
 364             winFocus = m_winLastFocused;
 365
 366         // if still no luck, do it the hard way
 367         if (!winFocus)
 368             winFocus = wxWindow::FindFocus();
 369
 370         if ( winFocus )
 371         {
 372 #ifdef __WXMSW__
 373             // If we are in a radio button group, start from the first item in the
 374             // group
 375             if ( event.IsFromTab() && wxIsKindOf(winFocus, wxRadioButton ) )
 376                 winFocus = wxGetFirstButtonInGroup((wxRadioButton*)winFocus);
 377 #endif
 378             // ok, we found the focus - now is it our child?
 379             start_node = children.Find( winFocus );
 380         }
 381
 382         if ( !start_node && m_winLastFocused )
 383         {
 384             // window which has focus isn't our child, fall back to the one
 385             // which had the focus the last time
 386             start_node = children.Find( m_winLastFocused );
 387         }
 388
 389         // if we still didn't find anything, we should start with the first one
 390         if ( !start_node )
 391         {
 392             start_node = children.GetFirst();
 393         }
 394
 395         // and the first child which we can try setting focus to is the next or
 396         // the previous one
 397         node = forward ? start_node->GetNext() : start_node->GetPrevious();
 398     }
 399
 400     // we want to cycle over all elements passing by NULL
 401     for ( ;; )
 402     {
 403         // don't go into infinite loop
 404         if ( start_node && node && node == start_node )
 405             break;
 406
 407         // Have we come to the last or first item on the panel?
 408         if ( !node )
 409         {
 410             if ( !start_node )
 411             {
 412                 // exit now as otherwise we'd loop forever
 413                 break;
 414             }
 415
 416             if ( !goingDown )
 417             {
 418                 // Check if our (maybe grand) parent is another panel: if this
 419                 // is the case, they will know what to do with this navigation
 420                 // key and so give them the chance to process it instead of
 421                 // looping inside this panel (normally, the focus will go to
 422                 // the next/previous item after this panel in the parent
 423                 // panel).
 424                 wxWindow *focussed_child_of_parent = m_winParent;
 425                 while ( parent )
 426                 {
 427                     // we don't want to tab into a different dialog or frame
 428                     if ( focussed_child_of_parent->IsTopLevel() )
 429                         break;
 430
 431                     event.SetCurrentFocus( focussed_child_of_parent );
 432                     if ( parent->GetEventHandler()->ProcessEvent( event ) )
 433                         return;
 434
 435                     focussed_child_of_parent = parent;
 436
 437                     parent = parent->GetParent();
 438                 }
 439             }
 440             //else: as the focus came from our parent, we definitely don't want
 441             //      to send it back to it!
 442
 443             // no, we are not inside another panel so process this ourself
 444             node = forward ? children.GetFirst() : children.GetLast();
 445
 446             continue;
 447         }
 448
 449         wxWindow *child = node->GetData();
 450
 451 #ifdef __WXMSW__
 452         if ( event.IsFromTab() )
 453         {
 454             if ( wxIsKindOf(child, wxRadioButton) )
 455             {
 456                 // only radio buttons with either wxRB_GROUP or wxRB_SINGLE
 457                 // can be tabbed to
 458                 if ( child->HasFlag(wxRB_GROUP) )
 459                 {
 460                     // need to tab into the active button within a group
 461                     wxRadioButton *rb = wxGetSelectedButtonInGroup((wxRadioButton*)child);
 462                     if ( rb )
 463                         child = rb;
 464                 }
 465                 else if ( !child->HasFlag(wxRB_SINGLE) )
 466                 {
 467                     node = forward ? node->GetNext() : node->GetPrevious();
 468                     continue;
 469                 }
 470             }
 471         }
 472         else if ( m_winLastFocused &&
 473                   wxIsKindOf(m_winLastFocused, wxRadioButton) &&
 474                   !m_winLastFocused->HasFlag(wxRB_SINGLE) )
 475         {
 476             // cursor keys don't navigate out of a radio button group so
 477             // find the correct radio button to focus
 478             if ( forward )
 479             {
 480                 child = wxGetNextButtonInGroup((wxRadioButton*)m_winLastFocused);
 481                 if ( !child )
 482                 {
 483                     // no next button in group, set it to the first button
 484                     child = wxGetFirstButtonInGroup((wxRadioButton*)m_winLastFocused);
 485                 }
 486             }
 487             else
 488             {
 489                 child = wxGetPreviousButtonInGroup((wxRadioButton*)m_winLastFocused);
 490                 if ( !child )
 491                 {
 492                     // no previous button in group, set it to the last button
 493                     child = wxGetLastButtonInGroup((wxRadioButton*)m_winLastFocused);
 494                 }
 495             }
 496
 497             if ( child == m_winLastFocused )
 498             {
 499                 // must be a group consisting of only one button therefore
 500                 // no need to send a navigation event
 501                 event.Skip(false);
 502                 return;
 503             }
 504         }
 505 #endif // __WXMSW__
 506
 507         if ( child->AcceptsFocusFromKeyboard() )
 508         {
 509             // if we're setting the focus to a child panel we should prevent it
 510             // from giving it to the child which had the focus the last time
 511             // and instead give it to the first/last child depending from which
 512             // direction we're coming
 513             event.SetEventObject(m_winParent);
 514
 515             // disable propagation for this call as otherwise the event might
 516             // bounce back to us.
 517             wxPropagationDisabler disableProp(event);
 518             if ( !child->GetEventHandler()->ProcessEvent(event) )
 519             {
 520                 // set it first in case SetFocusFromKbd() results in focus
 521                 // change too
 522                 m_winLastFocused = child;
 523
 524                 // everything is simple: just give focus to it
 525                 child->SetFocusFromKbd();
 526             }
 527             //else: the child manages its focus itself
 528
 529             event.Skip( false );
 530
 531             return;
 532         }
 533
 534         node = forward ? node->GetNext() : node->GetPrevious();
 535     }
 536
 537     // we cycled through all of our children and none of them wanted to accept
 538     // focus
 539     event.Skip();
 540 }
 541
 542 void wxControlContainer::HandleOnWindowDestroy(wxWindowBase *child)
 543 {
 544     if ( child == m_winLastFocused )
 545         m_winLastFocused = NULL;
 546 }
 547
 548 // ----------------------------------------------------------------------------
 549 // focus handling
 550 // ----------------------------------------------------------------------------
 551
 552 bool wxControlContainer::DoSetFocus()
 553 {
 554     wxLogTrace(TRACE_FOCUS, _T("SetFocus on wxPanel 0x%p."),
 555                m_winParent->GetHandle());
 556
 557     if (m_inSetFocus)
 558         return true;
 559
 560     // when the panel gets the focus we move the focus to either the last
 561     // window that had the focus or the first one that can get it unless the
 562     // focus had been already set to some other child
 563
 564     wxWindow *win = wxWindow::FindFocus();
 565     while ( win )
 566     {
 567         if ( win == m_winParent )
 568         {
 569             // our child already has focus, don't take it away from it
 570             return true;
 571         }
 572
 573         if ( win->IsTopLevel() )
 574         {
 575             // don't look beyond the first top level parent - useless and
 576             // unnecessary
 577             break;
 578         }
 579
 580         win = win->GetParent();
 581     }
 582
 583     // protect against infinite recursion:
 584     m_inSetFocus = true;
 585
 586     bool ret = SetFocusToChild();
 587
 588     m_inSetFocus = false;
 589
 590     return ret;
 591 }
 592
 593 void wxControlContainer::HandleOnFocus(wxFocusEvent& event)
 594 {
 595     wxLogTrace(TRACE_FOCUS, _T("OnFocus on wxPanel 0x%p, name: %s"),
 596                m_winParent->GetHandle(),
 597                m_winParent->GetName().c_str() );
 598
 599     DoSetFocus();
 600
 601     event.Skip();
 602 }
 603
 604 bool wxControlContainer::SetFocusToChild()
 605 {
 606     return wxSetFocusToChild(m_winParent, &m_winLastFocused);
 607 }
 608
 609 // ----------------------------------------------------------------------------
 610 // SetFocusToChild(): this function is used by wxPanel but also by wxFrame in
 611 // wxMSW, this is why it is outside of wxControlContainer class
 612 // ----------------------------------------------------------------------------
 613
 614 bool wxSetFocusToChild(wxWindow *win, wxWindow **childLastFocused)
 615 {
 616     wxCHECK_MSG( win, false, _T("wxSetFocusToChild(): invalid window") );
 617     wxCHECK_MSG( childLastFocused, false,
 618                  _T("wxSetFocusToChild(): NULL child poonter") );
 619
 620     if ( *childLastFocused )
 621     {
 622         // It might happen that the window got reparented
 623         if ( (*childLastFocused)->GetParent() == win )
 624         {
 625             wxLogTrace(TRACE_FOCUS,
 626                        _T("SetFocusToChild() => last child (0x%p)."),
 627                        (*childLastFocused)->GetHandle());
 628
 629             // not SetFocusFromKbd(): we're restoring focus back to the old
 630             // window and not setting it as the result of a kbd action
 631             (*childLastFocused)->SetFocus();
 632             return true;
 633         }
 634         else
 635         {
 636             // it doesn't count as such any more
 637             *childLastFocused = (wxWindow *)NULL;
 638         }
 639     }
 640
 641     // set the focus to the first child who wants it
 642     wxWindowList::compatibility_iterator node = win->GetChildren().GetFirst();
 643     while ( node )
 644     {
 645         wxWindow *child = node->GetData();
 646         node = node->GetNext();
 647
 648 #ifdef __WXMAC__
 649         if ( child->GetParent()->MacIsWindowScrollbar( child ) )
 650             continue;
 651 #endif
 652
 653         if ( child->AcceptsFocusFromKeyboard() && !child->IsTopLevel() )
 654         {
 655 #ifdef __WXMSW__
 656             // If a radiobutton is the first focusable child, search for the
 657             // selected radiobutton in the same group
 658             wxRadioButton* btn = wxDynamicCast(child, wxRadioButton);
 659             if (btn)
 660             {
 661                 wxRadioButton* selected = wxGetSelectedButtonInGroup(btn);
 662                 if (selected)
 663                     child = selected;
 664             }
 665 #endif
 666
 667             wxLogTrace(TRACE_FOCUS,
 668                        _T("SetFocusToChild() => first child (0x%p)."),
 669                        child->GetHandle());
 670
 671             *childLastFocused = child;
 672             child->SetFocusFromKbd();
 673             return true;
 674         }
 675     }
 676
 677     return false;
 678 }