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