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