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 #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
  21     #pragma implementation "containr.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 #ifndef WX_PRECOMP
  32     #include "wx/log.h"
  33     #include "wx/event.h"
  34     #include "wx/window.h"
  35 #endif //WX_PRECOMP
  36
  37 #include "wx/containr.h"
  38
  39 #ifdef __WXMAC__
  40     #include "wx/scrolbar.h"
  41 #endif
  42
  43 // ============================================================================
  44 // implementation
  45 // ============================================================================
  46
  47 wxControlContainer::wxControlContainer(wxWindow *winParent)
  48 {
  49     m_winParent = winParent;
  50
  51     m_winLastFocused =
  52     m_winTmpDefault =
  53     m_winDefault = NULL;
  54     m_inSetFocus = false;
  55 }
  56
  57 bool wxControlContainer::AcceptsFocus() const
  58 {
  59     // if we're not shown or disabled, we can't accept focus
  60     if ( m_winParent->IsShown() && m_winParent->IsEnabled() )
  61     {
  62         // otherwise we can accept focus either if we have no children at all
  63         // (in this case we're probably not used as a container) or only when
  64         // at least one child will accept focus
  65         wxWindowList::compatibility_iterator node = m_winParent->GetChildren().GetFirst();
  66         if ( !node )
  67             return TRUE;
  68
  69 #ifdef __WXMAC__
  70         // wxMac has eventually the two scrollbars as children, they don't count
  71         // as real children in the algorithm mentioned above
  72         bool hasRealChildren = false ;
  73 #endif
  74
  75         while ( node )
  76         {
  77             wxWindow *child = node->GetData();
  78
  79             if ( child->AcceptsFocus() )
  80             {
  81                 return TRUE;
  82             }
  83
  84 #ifdef __WXMAC__
  85             wxScrollBar *sb = wxDynamicCast( child , wxScrollBar ) ;
  86             if ( sb == NULL || !m_winParent->MacIsWindowScrollbar( sb ) )
  87                 hasRealChildren = true ;
  88 #endif
  89             node = node->GetNext();
  90         }
  91
  92 #ifdef __WXMAC__
  93         if ( !hasRealChildren )
  94             return TRUE ;
  95 #endif
  96     }
  97
  98     return FALSE;
  99 }
 100
 101 void wxControlContainer::SetLastFocus(wxWindow *win)
 102 {
 103     // the panel itself should never get the focus at all but if it does happen
 104     // temporarily (as it seems to do under wxGTK), at the very least don't
 105     // forget our previous m_winLastFocused
 106     if ( win != m_winParent )
 107     {
 108         // if we're setting the focus
 109         if ( win )
 110         {
 111             // find the last _immediate_ child which got focus
 112             wxWindow *winParent = win;
 113             while ( winParent != m_winParent )
 114             {
 115                 win = winParent;
 116                 winParent = win->GetParent();
 117
 118                 // Yes, this can happen, though in a totally pathological case.
 119                 // like when detaching a menubar from a frame with a child
 120                 // which has pushed itself as an event handler for the menubar.
 121                 // (under wxGTK)
 122
 123                 wxASSERT_MSG( winParent,
 124                               _T("Setting last focus for a window that is not our child?") );
 125             }
 126         }
 127
 128         m_winLastFocused = win;
 129
 130         if ( win )
 131         {
 132             wxLogTrace(_T("focus"), _T("Set last focus to %s(%s)"),
 133                        win->GetClassInfo()->GetClassName(),
 134                        win->GetLabel().c_str());
 135         }
 136         else
 137         {
 138             wxLogTrace(_T("focus"), _T("No more last focus"));
 139         }
 140     }
 141
 142     // propagate the last focus upwards so that our parent can set focus back
 143     // to us if it loses it now and regains later
 144     wxWindow *parent = m_winParent->GetParent();
 145     if ( parent )
 146     {
 147         wxChildFocusEvent eventFocus(m_winParent);
 148         parent->GetEventHandler()->ProcessEvent(eventFocus);
 149     }
 150 }
 151
 152 // ----------------------------------------------------------------------------
 153 // Keyboard handling - this is the place where the TAB traversal logic is
 154 // implemented. As this code is common to all ports, this ensures consistent
 155 // behaviour even if we don't specify how exactly the wxNavigationKeyEvent are
 156 // generated and this is done in platform specific code which also ensures that
 157 // we can follow the given platform standards.
 158 // ----------------------------------------------------------------------------
 159
 160 void wxControlContainer::HandleOnNavigationKey( wxNavigationKeyEvent& event )
 161 {
 162     wxWindow *parent = m_winParent->GetParent();
 163
 164     // the event is propagated downwards if the event emitter was our parent
 165     bool goingDown = event.GetEventObject() == parent;
 166
 167     const wxWindowList& children = m_winParent->GetChildren();
 168
 169     // there is not much to do if we don't have children and we're not
 170     // interested in "notebook page change" events here
 171     if ( !children.GetCount() || event.IsWindowChange() )
 172     {
 173         // let the parent process it unless it already comes from our parent
 174         // of we don't have any
 175         if ( goingDown ||
 176              !parent || !parent->GetEventHandler()->ProcessEvent(event) )
 177         {
 178             event.Skip();
 179         }
 180
 181         return;
 182     }
 183
 184     // where are we going?
 185     bool forward = event.GetDirection();
 186
 187     // the node of the children list from which we should start looking for the
 188     // next acceptable child
 189     wxWindowList::compatibility_iterator node, start_node;
 190
 191     // we should start from the first/last control and not from the one which
 192     // had focus the last time if we're propagating the event downwards because
 193     // for our parent we look like a single control
 194     if ( goingDown )
 195     {
 196         // just to be sure it's not used (normally this is not necessary, but
 197         // doesn't hurt neither)
 198         m_winLastFocused = (wxWindow *)NULL;
 199
 200         // start from first or last depending on where we're going
 201         node = forward ? children.GetFirst() : children.GetLast();
 202
 203         // we want to cycle over all nodes
 204         start_node = wxWindowList::compatibility_iterator();
 205     }
 206     else
 207     {
 208         // try to find the child which has the focus currently
 209
 210         // the event emitter might have done this for us
 211         wxWindow *winFocus = event.GetCurrentFocus();
 212
 213         // but if not, we might know where the focus was ourselves
 214         if (!winFocus)
 215             winFocus = m_winLastFocused;
 216
 217         // if still no luck, do it the hard way
 218         if (!winFocus)
 219             winFocus = wxWindow::FindFocus();
 220
 221         if ( winFocus )
 222         {
 223             // ok, we found the focus - now is it our child?
 224             start_node = children.Find( winFocus );
 225         }
 226         else
 227         {
 228             start_node = wxWindowList::compatibility_iterator();
 229         }
 230
 231         if ( !start_node && m_winLastFocused )
 232         {
 233             // window which has focus isn't our child, fall back to the one
 234             // which had the focus the last time
 235             start_node = children.Find( m_winLastFocused );
 236         }
 237
 238         // if we still didn't find anything, we should start with the first one
 239         if ( !start_node )
 240         {
 241             start_node = children.GetFirst();
 242         }
 243
 244         // and the first child which we can try setting focus to is the next or
 245         // the previous one
 246         node = forward ? start_node->GetNext() : start_node->GetPrevious();
 247     }
 248
 249     // we want to cycle over all elements passing by NULL
 250     while ( node != start_node )
 251     {
 252         // Have we come to the last or first item on the panel?
 253         if ( !node )
 254         {
 255             if ( !goingDown )
 256             {
 257                 // Check if our (may be grand) parent is another panel: if this
 258                 // is the case, they will know what to do with this navigation
 259                 // key and so give them the chance to process it instead of
 260                 // looping inside this panel (normally, the focus will go to
 261                 // the next/previous item after this panel in the parent
 262                 // panel).
 263                 wxWindow *focussed_child_of_parent = m_winParent;
 264                 while ( parent )
 265                 {
 266                     // we don't want to tab into a different dialog or frame
 267                     if ( focussed_child_of_parent->IsTopLevel() )
 268                         break;
 269
 270                     event.SetCurrentFocus( focussed_child_of_parent );
 271                     if ( parent->GetEventHandler()->ProcessEvent( event ) )
 272                         return;
 273
 274                     focussed_child_of_parent = parent;
 275
 276                     parent = parent->GetParent();
 277                 }
 278             }
 279             //else: as the focus came from our parent, we definitely don't want
 280             //      to send it back to it!
 281
 282             // no, we are not inside another panel so process this ourself
 283             node = forward ? children.GetFirst() : children.GetLast();
 284
 285             continue;
 286         }
 287
 288         wxWindow *child = node->GetData();
 289
 290         if ( child->AcceptsFocusFromKeyboard() )
 291         {
 292             // if we're setting the focus to a child panel we should prevent it
 293             // from giving it to the child which had the focus the last time
 294             // and instead give it to the first/last child depending from which
 295             // direction we're coming
 296             event.SetEventObject(m_winParent);
 297             // disable propagation for this call as otherwise the event might
 298             // bounce back to us.
 299             wxPropagationDisabler disableProp(event);
 300             if ( !child->GetEventHandler()->ProcessEvent(event) )
 301             {
 302                 // set it first in case SetFocusFromKbd() results in focus
 303                 // change too
 304                 m_winLastFocused = child;
 305
 306                 // everything is simple: just give focus to it
 307                 child->SetFocusFromKbd();
 308             }
 309             //else: the child manages its focus itself
 310
 311             event.Skip( FALSE );
 312
 313             return;
 314         }
 315
 316         node = forward ? node->GetNext() : node->GetPrevious();
 317     }
 318
 319     // we cycled through all of our children and none of them wanted to accept
 320     // focus
 321     event.Skip();
 322 }
 323
 324 void wxControlContainer::HandleOnWindowDestroy(wxWindowBase *child)
 325 {
 326     if ( child == m_winLastFocused )
 327         m_winLastFocused = NULL;
 328
 329     if ( child == m_winDefault )
 330         m_winDefault = NULL;
 331
 332     if ( child == m_winTmpDefault )
 333         m_winTmpDefault = NULL;
 334 }
 335
 336 // ----------------------------------------------------------------------------
 337 // focus handling
 338 // ----------------------------------------------------------------------------
 339
 340 bool wxControlContainer::DoSetFocus()
 341 {
 342     wxLogTrace(_T("focus"), _T("SetFocus on wxPanel 0x%08lx."),
 343                (unsigned long)m_winParent->GetHandle());
 344
 345     if (m_inSetFocus)
 346         return true;
 347
 348     m_inSetFocus = true;
 349
 350     // when the panel gets the focus we move the focus to either the last
 351     // window that had the focus or the first one that can get it unless the
 352     // focus had been already set to some other child
 353
 354     wxWindow *win = wxWindow::FindFocus();
 355     while ( win )
 356     {
 357         if ( win == m_winParent )
 358         {
 359             // our child already has focus, don't take it away from it
 360             return TRUE;
 361         }
 362
 363         if ( win->IsTopLevel() )
 364         {
 365             // don't look beyond the first top level parent - useless and
 366             // unnecessary
 367             break;
 368         }
 369
 370         win = win->GetParent();
 371     }
 372
 373     bool ret = SetFocusToChild();
 374
 375     m_inSetFocus = false;
 376
 377     return ret;
 378 }
 379
 380 void wxControlContainer::HandleOnFocus(wxFocusEvent& event)
 381 {
 382     wxLogTrace(_T("focus"), _T("OnFocus on wxPanel 0x%08lx, name: %s"),
 383                (unsigned long)m_winParent->GetHandle(),
 384                m_winParent->GetName().c_str() );
 385
 386     DoSetFocus();
 387
 388     event.Skip();
 389 }
 390
 391 bool wxControlContainer::SetFocusToChild()
 392 {
 393     return wxSetFocusToChild(m_winParent, &m_winLastFocused);
 394 }
 395
 396 // ----------------------------------------------------------------------------
 397 // SetFocusToChild(): this function is used by wxPanel but also by wxFrame in
 398 // wxMSW, this is why it is outside of wxControlContainer class
 399 // ----------------------------------------------------------------------------
 400
 401 bool wxSetFocusToChild(wxWindow *win, wxWindow **childLastFocused)
 402 {
 403     wxCHECK_MSG( win, FALSE, _T("wxSetFocusToChild(): invalid window") );
 404     wxCHECK_MSG( childLastFocused, FALSE,
 405                  _T("wxSetFocusToChild(): NULL child poonter") );
 406
 407     if ( *childLastFocused )
 408     {
 409         // It might happen that the window got reparented
 410         if ( (*childLastFocused)->GetParent() == win )
 411         {
 412             wxLogTrace(_T("focus"),
 413                        _T("SetFocusToChild() => last child (0x%08lx)."),
 414                        (unsigned long)(*childLastFocused)->GetHandle());
 415
 416             // not SetFocusFromKbd(): we're restoring focus back to the old
 417             // window and not setting it as the result of a kbd action
 418             (*childLastFocused)->SetFocus();
 419             return TRUE;
 420         }
 421         else
 422         {
 423             // it doesn't count as such any more
 424             *childLastFocused = (wxWindow *)NULL;
 425         }
 426     }
 427
 428     // set the focus to the first child who wants it
 429     wxWindowList::compatibility_iterator node = win->GetChildren().GetFirst();
 430     while ( node )
 431     {
 432         wxWindow *child = node->GetData();
 433
 434         if ( child->AcceptsFocusFromKeyboard() && !child->IsTopLevel() )
 435         {
 436             wxLogTrace(_T("focus"),
 437                        _T("SetFocusToChild() => first child (0x%08lx)."),
 438                        (unsigned long)child->GetHandle());
 439
 440             *childLastFocused = child;
 441             child->SetFocusFromKbd();
 442             return TRUE;
 443         }
 444
 445         node = node->GetNext();
 446     }
 447
 448     return FALSE;
 449 }
 450