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