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