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