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