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