src/generic/panelg.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/generic/panelg.cpp
   3 // Purpose:     wxPanel and the keyboard handling code
   4 // Author:      Julian Smart, Robert Roebling, Vadim Zeitlin
   5 // Modified by:
   6 // Created:     04/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Julian Smart and Markus Holzem
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #ifdef __GNUG__
  21     #pragma implementation "panelg.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/object.h"
  33     #include "wx/font.h"
  34     #include "wx/colour.h"
  35     #include "wx/settings.h"
  36     #include "wx/log.h"
  37 #endif
  38
  39 #include "wx/generic/panelg.h"
  40
  41 // ----------------------------------------------------------------------------
  42 // wxWin macros
  43 // ----------------------------------------------------------------------------
  44
  45 IMPLEMENT_DYNAMIC_CLASS(wxPanel, wxWindow)
  46
  47 BEGIN_EVENT_TABLE(wxPanel, wxWindow)
  48   EVT_SYS_COLOUR_CHANGED(wxPanel::OnSysColourChanged)
  49   EVT_SET_FOCUS(wxPanel::OnFocus)
  50   EVT_NAVIGATION_KEY(wxPanel::OnNavigationKey)
  51   EVT_SIZE(wxPanel::OnSize)
  52 END_EVENT_TABLE()
  53
  54 // ============================================================================
  55 // implementation
  56 // ============================================================================
  57
  58 // ----------------------------------------------------------------------------
  59 // wxPanel creation
  60 // ----------------------------------------------------------------------------
  61
  62 void wxPanel::Init()
  63 {
  64     m_winLastFocused = (wxWindow *)NULL;
  65 #if wxUSE_BUTTON
  66     m_btnDefault = (wxButton *)NULL;
  67 #endif // wxUSE_BUTTON
  68 }
  69
  70 bool wxPanel::Create(wxWindow *parent, wxWindowID id,
  71                      const wxPoint& pos,
  72                      const wxSize& size,
  73                      long style,
  74                      const wxString& name)
  75 {
  76     return wxWindow::Create(parent, id, pos, size, style, name);
  77 }
  78
  79 // ----------------------------------------------------------------------------
  80 // misc
  81 // ----------------------------------------------------------------------------
  82
  83 void wxPanel::InitDialog()
  84 {
  85     wxInitDialogEvent event(GetId());
  86     event.SetEventObject(this);
  87     GetEventHandler()->ProcessEvent(event);
  88 }
  89
  90 // Responds to colour changes, and passes event on to children.
  91 void wxPanel::OnSysColourChanged(wxSysColourChangedEvent& event)
  92 {
  93     SetBackgroundColour(wxSystemSettings::GetSystemColour(wxSYS_COLOUR_3DFACE));
  94     Refresh();
  95
  96     // Propagate the event to the non-top-level children
  97     wxWindow::OnSysColourChanged(event);
  98 }
  99
 100 void wxPanel::OnSize(wxSizeEvent& WXUNUSED(event))
 101 {
 102 #if wxUSE_CONSTRAINTS
 103     if (GetAutoLayout())
 104         Layout();
 105 #endif
 106 }
 107
 108 // ----------------------------------------------------------------------------
 109 // Keyboard handling - this is the place where the TAB traversal logic is
 110 // implemented. As this code is common to all ports, this ensures consistent
 111 // behaviour even if we don't specify how exactly the wxNavigationKeyEvent are
 112 // generated and this is done in platform specific code which also ensures that
 113 // we can follow the given platform standards.
 114 // ----------------------------------------------------------------------------
 115
 116 void wxPanel::OnNavigationKey( wxNavigationKeyEvent& event )
 117 {
 118     // the event is propagated downwards if the event emitter was our parent
 119     bool goingDown = event.GetEventObject() == GetParent();
 120
 121     const wxWindowList& children = GetChildren();
 122
 123     // there is not much to do if we don't have children and we're not
 124     // interested in "notebook page change" events here
 125     if ( !children.GetCount() || event.IsWindowChange() )
 126     {
 127         // let the parent process it unless it already comes from our parent
 128         // of we don't have any
 129         wxWindow *parent = GetParent();
 130         if ( goingDown ||
 131              !parent || !parent->GetEventHandler()->ProcessEvent(event) )
 132         {
 133             event.Skip();
 134         }
 135
 136         return;
 137     }
 138
 139     // where are we going?
 140     bool forward = event.GetDirection();
 141
 142     // the node of the children list from which we should start looking for the
 143     // next acceptable child
 144     wxWindowList::Node *node, *start_node;
 145
 146     // we should start from the first/last control and not from the one which
 147     // had focus the last time if we're propagating the event downwards because
 148     // for our parent we look like a single control
 149     if ( goingDown )
 150     {
 151         // just to be sure it's not used (normally this is not necessary, but
 152         // doesn't hurt neither)
 153         m_winLastFocused = (wxWindow *)NULL;
 154
 155         // start from first or last depending on where we're going
 156         node = forward ? children.GetFirst() : children.GetLast();
 157
 158         // we want to cycle over all nodes
 159         start_node = (wxWindowList::Node *)NULL;
 160     }
 161     else
 162     {
 163         // try to find the child which has the focus currently
 164
 165         // the event emitter might have done this for us
 166         wxWindow *winFocus = event.GetCurrentFocus();
 167
 168         // but if not, we might know where the focus was ourselves
 169         if (!winFocus)
 170             winFocus = m_winLastFocused;
 171
 172         // if still no luck, do it the hard way
 173         if (!winFocus)
 174             winFocus = wxWindow::FindFocus();
 175
 176         if ( winFocus )
 177         {
 178             // ok, we found the focus - now is it our child?
 179             start_node = children.Find( winFocus );
 180         }
 181         else
 182         {
 183             start_node = (wxWindowList::Node *)NULL;
 184         }
 185
 186         if ( !start_node && m_winLastFocused )
 187         {
 188             // window which has focus isn't our child, fall back to the one
 189             // which had the focus the last time
 190             start_node = children.Find( m_winLastFocused );
 191         }
 192
 193         // if we still didn't find anything, we should start with the first one
 194         if ( !start_node )
 195         {
 196             start_node = children.GetFirst();
 197         }
 198
 199         // and the first child which we can try setting focus to is the next or
 200         // the previous one
 201         node = forward ? start_node->GetNext() : start_node->GetPrevious();
 202     }
 203
 204     // we want to cycle over all elements passing by NULL
 205     while ( node != start_node )
 206     {
 207         // Have we come to the last or first item on the panel?
 208         if ( !node )
 209         {
 210             if ( !goingDown )
 211             {
 212                 // Check if our (may be grand) parent is another panel: if this
 213                 // is the case, they will know what to do with this navigation
 214                 // key and so give them the chance to process it instead of
 215                 // looping inside this panel (normally, the focus will go to
 216                 // the next/previous item after this panel in the parent
 217                 // panel).
 218                 wxWindow *focussed_child_of_parent = this;
 219                 for ( wxWindow *parent = GetParent();
 220                       parent;
 221                       parent = parent->GetParent() )
 222                 {
 223                     // we don't want to tab into a different dialog or frame
 224                     if ( focussed_child_of_parent->IsTopLevel() )
 225                         break;
 226
 227                     event.SetCurrentFocus( focussed_child_of_parent );
 228                     if (parent->GetEventHandler()->ProcessEvent( event ))
 229                         return;
 230
 231                     focussed_child_of_parent = parent;
 232                 }
 233             }
 234             //else: as the focus came from our parent, we definitely don't want
 235             //      to send it back to it!
 236
 237             // no, we are not inside another panel so process this ourself
 238             node = forward ? children.GetFirst() : children.GetLast();
 239
 240             continue;
 241         }
 242
 243         wxWindow *child = node->GetData();
 244
 245         if ( child->AcceptsFocusFromKeyboard() )
 246         {
 247             m_winLastFocused = child;  // should be redundant, but it is not
 248
 249             // if we're setting the focus to a child panel we should prevent it
 250             // from giving it to the child which had the focus the last time
 251             // and instead give it to the first/last child depending from which
 252             // direction we're coming
 253             wxPanel *subpanel = wxDynamicCast(child, wxPanel);
 254             if ( subpanel )
 255             {
 256                 // trick the panel into thinking that it got the navigation
 257                 // event - instead of duplicating all the code here
 258                 //
 259                 // make sure that we do trick it by setting all the parameters
 260                 // correctly (consistently with the code in this very function
 261                 // above) and that it starts from the very beginning/end by
 262                 // using SetLastFocus(NULL)
 263                 subpanel->SetLastFocus((wxWindow *)NULL);
 264             }
 265
 266             event.SetEventObject(this);
 267             if ( !child->GetEventHandler()->ProcessEvent(event) )
 268             {
 269                 // everything is simple: just give focus to it
 270                 child->SetFocus();
 271             }
 272             //else: the child manages its focus itself
 273
 274             event.Skip( FALSE );
 275             return;
 276         }
 277
 278         node = forward ? node->GetNext() : node->GetPrevious();
 279     }
 280
 281     // we cycled through all of our children and none of them wanted to accept
 282     // focus
 283     event.Skip();
 284 }
 285
 286 void wxPanel::RemoveChild(wxWindowBase *child)
 287 {
 288     if ( child == m_winLastFocused )
 289         m_winLastFocused = NULL;
 290     wxWindow::RemoveChild(child);
 291 }
 292
 293 void wxPanel::SetFocus()
 294 {
 295     wxLogTrace(_T("focus"), _T("SetFocus on wxPanel 0x%08x."), GetHandle());
 296
 297     // If the panel gets the focus *by way of getting it set directly*
 298     // we move the focus to the first window that can get it.
 299
 300     // VZ: no, we set the focus to the last window too. I don't understand why
 301     //     should we make this distinction: if an app wants to set focus to
 302     //     some precise control, it may always do it directly, but if we don't
 303     //     use m_winLastFocused here, the focus won't be set correctly after a
 304     //     notebook page change nor after frame activation under MSW (it calls
 305     //     SetFocus too)
 306     //
 307     // RR: yes, when I the tab key to navigate in a panel with some controls and
 308     //     a notebook and the focus jumps to the notebook (typically coming from
 309     //     a button at the top) the notebook should focus the first child in the
 310     //     current notebook page, not the last one which would otherwise get the
 311     //     focus if you used the tab key to navigate from the current notebook
 312     //     page to button at the bottom. See every page in the controls sample.
 313     //
 314     // VZ: ok, but this still doesn't (at least I don't see how it can) take
 315     //     care of first/last child problem: i.e. if Shift-TAB is pressed in a
 316     //     situation like above, the focus should be given to the last child,
 317     //     not the first one (and not to the last focused one neither) - I
 318     //     think my addition to OnNavigationKey() above takes care of it.
 319     //     Keeping #ifdef __WXGTK__ for now, but please try removing it and see
 320     //     what happens.
 321     //
 322     // RR: Removed for now. Let's see what happens..
 323
 324     if ( !SetFocusToChild() )
 325     {
 326         wxWindow::SetFocus();
 327     }
 328 }
 329
 330 void wxPanel::OnFocus(wxFocusEvent& event)
 331 {
 332     wxLogTrace(_T("focus"), _T("OnFocus on wxPanel 0x%08x, name: %s"), GetHandle(), GetName().c_str() );
 333
 334     // If the panel gets 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 wxPanel::SetFocusToChild()
 343 {
 344     return wxSetFocusToChild(this, &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 wxPanel 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)->SetFocus();
 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->SetFocus();
 391             return TRUE;
 392         }
 393
 394         node = node->GetNext();
 395     }
 396
 397     return FALSE;
 398 }