src/gtk/slider.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/gtk/slider.cpp
   3 // Purpose:
   4 // Author:      Robert Roebling
   5 // Id:          $Id$
   6 // Copyright:   (c) 1998 Robert Roebling
   7 // Licence:     wxWindows licence
   8 /////////////////////////////////////////////////////////////////////////////
   9
  10 // For compilers that support precompilation, includes "wx.h".
  11 #include "wx/wxprec.h"
  12
  13 #if wxUSE_SLIDER
  14
  15 #include "wx/slider.h"
  16
  17 #ifndef WX_PRECOMP
  18     #include "wx/utils.h"
  19 #endif
  20
  21 #include "wx/math.h"
  22 #include "wx/gtk/private.h"
  23
  24 //-----------------------------------------------------------------------------
  25 // data
  26 //-----------------------------------------------------------------------------
  27
  28 extern bool g_blockEventsOnDrag;
  29
  30 // ----------------------------------------------------------------------------
  31 // helper functions
  32 // ----------------------------------------------------------------------------
  33
  34 // compare 2 adjustment values up to some (hardcoded) precision
  35 static inline bool AreSameAdjustValues(double x, double y)
  36 {
  37     return fabs(x - y) < 0.02;
  38 }
  39
  40 static inline int AdjustValueToInt(double x)
  41 {
  42     // we want to round to the nearest integer, i.e. 0.9 is rounded to 1 and
  43     // -0.9 is rounded to -1
  44     return (int)(x < 0 ? x - 0.5 : x + 0.5);
  45 }
  46
  47 // process a scroll event
  48 static void
  49 ProcessScrollEvent(wxSlider *win, wxEventType evtType, double dvalue)
  50 {
  51     const int orient = win->HasFlag(wxSL_VERTICAL) ? wxVERTICAL
  52                                                    : wxHORIZONTAL;
  53
  54     const int value = (int)(dvalue < 0 ? dvalue - 0.5 : dvalue + 0.5);
  55
  56     // if we have any "special" event (i.e. the value changed by a line or a
  57     // page), send this specific event first
  58     if ( evtType != wxEVT_NULL )
  59     {
  60         wxScrollEvent event( evtType, win->GetId(), value, orient );
  61         event.SetEventObject( win );
  62         win->GetEventHandler()->ProcessEvent( event );
  63     }
  64
  65     // but, in any case, except if we're dragging the slider (and so the change
  66     // is not definitive), send a generic "changed" event
  67     if ( evtType != wxEVT_SCROLL_THUMBTRACK )
  68     {
  69         wxScrollEvent event(wxEVT_SCROLL_CHANGED, win->GetId(), value, orient);
  70         event.SetEventObject( win );
  71         win->GetEventHandler()->ProcessEvent( event );
  72     }
  73
  74     // and also generate a command event for compatibility
  75     wxCommandEvent event( wxEVT_COMMAND_SLIDER_UPDATED, win->GetId() );
  76     event.SetEventObject( win );
  77     event.SetInt( value );
  78     win->GetEventHandler()->ProcessEvent( event );
  79 }
  80
  81 //-----------------------------------------------------------------------------
  82 // "value_changed"
  83 //-----------------------------------------------------------------------------
  84
  85 extern "C" {
  86 static void gtk_slider_callback( GtkAdjustment *adjust,
  87                                  wxSlider *win )
  88 {
  89     if (g_isIdle) wxapp_install_idle_handler();
  90
  91     if (!win->m_hasVMT) return;
  92     if (g_blockEventsOnDrag) return;
  93
  94     const double dvalue = adjust->value;
  95     const double diff = dvalue - win->m_oldPos;
  96     if ( AreSameAdjustValues(diff, 0) )
  97         return;
  98
  99     wxEventType evtType;
 100     if ( win->m_isScrolling )
 101         evtType = wxEVT_SCROLL_THUMBTRACK;
 102     // it could seem that UP/DOWN are inversed but this is what wxMSW does
 103     else if ( AreSameAdjustValues(diff, adjust->step_increment) )
 104         evtType = wxEVT_SCROLL_LINEDOWN;
 105     else if ( AreSameAdjustValues(diff, -adjust->step_increment) )
 106         evtType = wxEVT_SCROLL_LINEUP;
 107     else if ( AreSameAdjustValues(diff, adjust->page_increment) )
 108         evtType = wxEVT_SCROLL_PAGEDOWN;
 109     else if ( AreSameAdjustValues(diff, -adjust->page_increment) )
 110         evtType = wxEVT_SCROLL_PAGEUP;
 111     else if ( AreSameAdjustValues(adjust->value, adjust->lower) )
 112         evtType = wxEVT_SCROLL_TOP;
 113     else if ( AreSameAdjustValues(adjust->value, adjust->upper) )
 114         evtType = wxEVT_SCROLL_BOTTOM;
 115     else
 116         evtType = wxEVT_NULL; // wxEVT_SCROLL_CHANGED will still be generated
 117
 118     ProcessScrollEvent(win, evtType, dvalue);
 119
 120     win->m_oldPos = dvalue;
 121 }
 122
 123 static gint gtk_slider_button_press_callback( GtkWidget * /* widget */,
 124                                               GdkEventButton * /* gdk_event */,
 125                                               wxWindowGTK *win)
 126 {
 127     // indicate that the thumb is being dragged with the mouse
 128     win->m_isScrolling = true;
 129
 130     return FALSE;
 131 }
 132
 133 static gint gtk_slider_button_release_callback( GtkWidget *scale,
 134                                                 GdkEventButton * /* gdk_event */,
 135                                                 wxSlider *win)
 136 {
 137     // not scrolling any longer
 138     win->m_isScrolling = false;
 139
 140     ProcessScrollEvent(win, wxEVT_SCROLL_THUMBRELEASE,
 141                        GTK_RANGE(scale)->adjustment->value);
 142
 143     return FALSE;
 144 }
 145
 146 }
 147
 148 //-----------------------------------------------------------------------------
 149 // wxSlider
 150 //-----------------------------------------------------------------------------
 151
 152 IMPLEMENT_DYNAMIC_CLASS(wxSlider,wxControl)
 153
 154 bool wxSlider::Create(wxWindow *parent, wxWindowID id,
 155         int value, int minValue, int maxValue,
 156         const wxPoint& pos, const wxSize& size,
 157         long style, const wxValidator& validator, const wxString& name )
 158 {
 159     m_acceptsFocus = true;
 160     m_needParent = true;
 161
 162     if (!PreCreation( parent, pos, size ) ||
 163         !CreateBase( parent, id, pos, size, style, validator, name ))
 164     {
 165         wxFAIL_MSG( wxT("wxSlider creation failed") );
 166         return false;
 167     }
 168
 169     m_oldPos = 0.0;
 170
 171     if (style & wxSL_VERTICAL)
 172         m_widget = gtk_vscale_new( (GtkAdjustment *) NULL );
 173     else
 174         m_widget = gtk_hscale_new( (GtkAdjustment *) NULL );
 175
 176     if (style & wxSL_LABELS)
 177     {
 178         gtk_scale_set_draw_value( GTK_SCALE( m_widget ), TRUE );
 179         gtk_scale_set_digits( GTK_SCALE( m_widget ), 0 );
 180
 181         /* labels need more space and too small window will
 182            cause junk to appear on the dialog */
 183         if (style & wxSL_VERTICAL)
 184         {
 185             wxSize sz( size );
 186             if (sz.x < 35)
 187             {
 188                 sz.x = 35;
 189                 SetSize( sz );
 190             }
 191         }
 192         else
 193         {
 194             wxSize sz( size );
 195             if (sz.y < 35)
 196             {
 197                 sz.y = 35;
 198                 SetSize( sz );
 199             }
 200         }
 201     }
 202     else
 203         gtk_scale_set_draw_value( GTK_SCALE( m_widget ), FALSE );
 204
 205     m_adjust = gtk_range_get_adjustment( GTK_RANGE(m_widget) );
 206
 207     if (style & wxSL_INVERSE)
 208         gtk_range_set_inverted( GTK_RANGE(m_widget), TRUE );
 209
 210     GtkEnableEvents();
 211     g_signal_connect (m_widget, "button_press_event",
 212                       G_CALLBACK (gtk_slider_button_press_callback),
 213                       this);
 214     g_signal_connect (m_widget, "button_release_event",
 215                       G_CALLBACK (gtk_slider_button_release_callback),
 216                       this);
 217
 218     SetRange( minValue, maxValue );
 219     SetValue( value );
 220
 221     m_parent->DoAddChild( this );
 222
 223     PostCreation(size);
 224
 225     return true;
 226 }
 227
 228 int wxSlider::GetValue() const
 229 {
 230     return AdjustValueToInt(m_adjust->value);
 231 }
 232
 233 void wxSlider::SetValue( int value )
 234 {
 235     double fpos = (double)value;
 236     m_oldPos = fpos;
 237     if ( AreSameAdjustValues(fpos, m_adjust->value) )
 238         return;
 239
 240     m_adjust->value = fpos;
 241
 242     GtkDisableEvents();
 243
 244     g_signal_emit_by_name (m_adjust, "value_changed");
 245
 246     GtkEnableEvents();
 247 }
 248
 249 void wxSlider::SetRange( int minValue, int maxValue )
 250 {
 251     double fmin = (double)minValue;
 252     double fmax = (double)maxValue;
 253
 254     if ((fabs(fmin-m_adjust->lower) < 0.2) &&
 255         (fabs(fmax-m_adjust->upper) < 0.2))
 256     {
 257         return;
 258     }
 259
 260     m_adjust->lower = fmin;
 261     m_adjust->upper = fmax;
 262     m_adjust->step_increment = 1.0;
 263     m_adjust->page_increment = ceil((fmax-fmin) / 10.0);
 264
 265     GtkDisableEvents();
 266
 267     g_signal_emit_by_name (m_adjust, "changed");
 268
 269     GtkEnableEvents();
 270 }
 271
 272 int wxSlider::GetMin() const
 273 {
 274     return (int)ceil(m_adjust->lower);
 275 }
 276
 277 int wxSlider::GetMax() const
 278 {
 279     return (int)ceil(m_adjust->upper);
 280 }
 281
 282 void wxSlider::SetPageSize( int pageSize )
 283 {
 284     double fpage = (double)pageSize;
 285
 286     if (fabs(fpage-m_adjust->page_increment) < 0.2) return;
 287
 288     m_adjust->page_increment = fpage;
 289
 290     GtkDisableEvents();
 291
 292     g_signal_emit_by_name (m_adjust, "changed");
 293
 294     GtkEnableEvents();
 295 }
 296
 297 int wxSlider::GetPageSize() const
 298 {
 299     return (int)ceil(m_adjust->page_increment);
 300 }
 301
 302 void wxSlider::SetThumbLength( int len )
 303 {
 304     double flen = (double)len;
 305
 306     if (fabs(flen-m_adjust->page_size) < 0.2) return;
 307
 308     m_adjust->page_size = flen;
 309
 310     GtkDisableEvents();
 311
 312     g_signal_emit_by_name (m_adjust, "changed");
 313
 314     GtkEnableEvents();
 315 }
 316
 317 int wxSlider::GetThumbLength() const
 318 {
 319     return (int)ceil(m_adjust->page_size);
 320 }
 321
 322 void wxSlider::SetLineSize( int WXUNUSED(lineSize) )
 323 {
 324 }
 325
 326 int wxSlider::GetLineSize() const
 327 {
 328     return 0;
 329 }
 330
 331 bool wxSlider::IsOwnGtkWindow( GdkWindow *window )
 332 {
 333     GtkRange *range = GTK_RANGE(m_widget);
 334     return (range->event_window == window);
 335 }
 336
 337 void wxSlider::GtkDisableEvents()
 338 {
 339     g_signal_handlers_disconnect_by_func (m_adjust,
 340                                           (gpointer) gtk_slider_callback,
 341                                           this);
 342 }
 343
 344 void wxSlider::GtkEnableEvents()
 345 {
 346     g_signal_connect (m_adjust, "value_changed",
 347                       G_CALLBACK (gtk_slider_callback), this);
 348 }
 349
 350 // static
 351 wxVisualAttributes
 352 wxSlider::GetClassDefaultAttributes(wxWindowVariant WXUNUSED(variant))
 353 {
 354     return GetDefaultAttributesFromGTKWidget(gtk_vscale_new);
 355 }
 356
 357 #endif // wxUSE_SLIDER