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