src/gtk/slider.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        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 #include "wx/slider.h"
  14
  15 #if wxUSE_SLIDER
  16
  17 #include "wx/utils.h"
  18 #include "wx/math.h"
  19 #include "wx/gtk/private.h"
  20
  21 //-----------------------------------------------------------------------------
  22 // idle system
  23 //-----------------------------------------------------------------------------
  24
  25 extern void wxapp_install_idle_handler();
  26 extern bool g_isIdle;
  27
  28 //-----------------------------------------------------------------------------
  29 // data
  30 //-----------------------------------------------------------------------------
  31
  32 extern bool g_blockEventsOnDrag;
  33
  34 // ----------------------------------------------------------------------------
  35 // helper functions
  36 // ----------------------------------------------------------------------------
  37
  38 // compare 2 adjustment values up to some (hardcoded) precision
  39 static inline bool AreSameAdjustValues(double x, double y)
  40 {
  41     return fabs(x - y) < 0.02;
  42 }
  43
  44 static inline int AdjustValueToInt(double x)
  45 {
  46     // we want to round to the nearest integer, i.e. 0.9 is rounded to 1 and
  47     // -0.9 is rounded to -1
  48     return (int)(x < 0 ? x - 0.5 : x + 0.5);
  49 }
  50
  51 // process a scroll event
  52 static void
  53 ProcessScrollEvent(wxSlider *win, wxEventType evtType, double dvalue)
  54 {
  55     int orient = win->GetWindowStyleFlag() & wxSL_VERTICAL ? wxVERTICAL
  56                                                            : wxHORIZONTAL;
  57
  58     int value = (int)(dvalue < 0 ? dvalue - 0.5 : dvalue + 0.5);
  59     wxScrollEvent event( evtType, win->GetId(), value, orient );
  60     event.SetEventObject( win );
  61     win->GetEventHandler()->ProcessEvent( event );
  62
  63     if ( evtType != wxEVT_SCROLL_THUMBTRACK )
  64     {
  65         wxScrollEvent event2(wxEVT_SCROLL_CHANGED, win->GetId(), value, orient);
  66         event2.SetEventObject( win );
  67         win->GetEventHandler()->ProcessEvent( event2 );
  68     }
  69
  70     wxCommandEvent cevent( wxEVT_COMMAND_SLIDER_UPDATED, win->GetId() );
  71     cevent.SetEventObject( win );
  72     cevent.SetInt( value );
  73     win->GetEventHandler()->ProcessEvent( cevent );
  74 }
  75
  76 //-----------------------------------------------------------------------------
  77 // "value_changed"
  78 //-----------------------------------------------------------------------------
  79
  80 extern "C" {
  81 static void gtk_slider_callback( GtkAdjustment *adjust,
  82                                  SCROLLBAR_CBACK_ARG
  83                                  wxSlider *win )
  84 {
  85     if (g_isIdle) wxapp_install_idle_handler();
  86
  87     if (!win->m_hasVMT) return;
  88     if (g_blockEventsOnDrag) return;
  89
  90     const double dvalue = adjust->value;
  91     const double diff = dvalue - win->m_oldPos;
  92     if ( AreSameAdjustValues(diff, 0) )
  93         return;
  94
  95     wxEventType evtType;
  96     if ( win->m_isScrolling )
  97         evtType = wxEVT_SCROLL_THUMBTRACK;
  98     // it could seem that UP/DOWN are inversed but this is what wxMSW does
  99     else if ( AreSameAdjustValues(diff, adjust->step_increment) )
 100         evtType = wxEVT_SCROLL_LINEDOWN;
 101     else if ( AreSameAdjustValues(diff, -adjust->step_increment) )
 102         evtType = wxEVT_SCROLL_LINEUP;
 103     else if ( AreSameAdjustValues(diff, adjust->page_increment) )
 104         evtType = wxEVT_SCROLL_PAGEDOWN;
 105     else if ( AreSameAdjustValues(diff, -adjust->page_increment) )
 106         evtType = wxEVT_SCROLL_PAGEUP;
 107     else if ( AreSameAdjustValues(adjust->value, adjust->lower) )
 108         evtType = wxEVT_SCROLL_TOP;
 109     else if ( AreSameAdjustValues(adjust->value, adjust->upper) )
 110         evtType = wxEVT_SCROLL_BOTTOM;
 111
 112     ProcessScrollEvent(win, evtType, dvalue);
 113
 114     win->m_oldPos = dvalue;
 115 }
 116
 117 static gint gtk_slider_button_press_callback( GtkWidget * /* widget */,
 118                                               GdkEventButton * /* gdk_event */,
 119                                               wxWindowGTK *win)
 120 {
 121     // indicate that the thumb is being dragged with the mouse
 122     win->m_isScrolling = true;
 123
 124     return FALSE;
 125 }
 126
 127 static gint gtk_slider_button_release_callback( GtkWidget *scale,
 128                                                 GdkEventButton * /* gdk_event */,
 129                                                 wxSlider *win)
 130 {
 131     // not scrolling any longer
 132     win->m_isScrolling = false;
 133
 134     ProcessScrollEvent(win, wxEVT_SCROLL_THUMBRELEASE,
 135                        GTK_RANGE(scale)->adjustment->value);
 136
 137     return FALSE;
 138 }
 139
 140 }
 141
 142 //-----------------------------------------------------------------------------
 143 // wxSlider
 144 //-----------------------------------------------------------------------------
 145
 146 IMPLEMENT_DYNAMIC_CLASS(wxSlider,wxControl)
 147
 148 bool wxSlider::Create(wxWindow *parent, wxWindowID id,
 149         int value, int minValue, int maxValue,
 150         const wxPoint& pos, const wxSize& size,
 151         long style, const wxValidator& validator, const wxString& name )
 152 {
 153     m_acceptsFocus = TRUE;
 154     m_needParent = TRUE;
 155
 156     if (!PreCreation( parent, pos, size ) ||
 157         !CreateBase( parent, id, pos, size, style, validator, name ))
 158     {
 159         wxFAIL_MSG( wxT("wxSlider creation failed") );
 160         return FALSE;
 161     }
 162
 163     m_oldPos = 0.0;
 164
 165     if (style & wxSL_VERTICAL)
 166         m_widget = gtk_vscale_new( (GtkAdjustment *) NULL );
 167     else
 168         m_widget = gtk_hscale_new( (GtkAdjustment *) NULL );
 169
 170     if (style & wxSL_LABELS)
 171     {
 172         gtk_scale_set_draw_value( GTK_SCALE( m_widget ), TRUE );
 173         gtk_scale_set_digits( GTK_SCALE( m_widget ), 0 );
 174
 175         /* labels need more space and too small window will
 176            cause junk to appear on the dialog */
 177         if (style & wxSL_VERTICAL)
 178         {
 179             wxSize sz( size );
 180             if (sz.x < 35)
 181             {
 182                 sz.x = 35;
 183                 SetSize( sz );
 184             }
 185         }
 186         else
 187         {
 188             wxSize sz( size );
 189             if (sz.y < 35)
 190             {
 191                 sz.y = 35;
 192                 SetSize( sz );
 193             }
 194         }
 195     }
 196     else
 197         gtk_scale_set_draw_value( GTK_SCALE( m_widget ), FALSE );
 198
 199     m_adjust = gtk_range_get_adjustment( GTK_RANGE(m_widget) );
 200
 201     if (style & wxSL_INVERSE)
 202         gtk_range_set_inverted( GTK_RANGE(m_widget), TRUE );
 203
 204     GtkEnableEvents();
 205     gtk_signal_connect( GTK_OBJECT(m_widget),
 206                         "button_press_event",
 207                         (GtkSignalFunc)gtk_slider_button_press_callback,
 208                         (gpointer) this );
 209     gtk_signal_connect( GTK_OBJECT(m_widget),
 210                         "button_release_event",
 211                         (GtkSignalFunc)gtk_slider_button_release_callback,
 212                         (gpointer) this );
 213
 214     SetRange( minValue, maxValue );
 215     SetValue( value );
 216
 217     m_parent->DoAddChild( this );
 218
 219     PostCreation(size);
 220
 221     return TRUE;
 222 }
 223
 224 int wxSlider::GetValue() const
 225 {
 226     return AdjustValueToInt(m_adjust->value);
 227 }
 228
 229 void wxSlider::SetValue( int value )
 230 {
 231     double fpos = (double)value;
 232     m_oldPos = fpos;
 233     if ( AreSameAdjustValues(fpos, m_adjust->value) )
 234         return;
 235
 236     m_adjust->value = fpos;
 237
 238     GtkDisableEvents();
 239
 240     gtk_signal_emit_by_name( GTK_OBJECT(m_adjust), "value_changed" );
 241
 242     GtkEnableEvents();
 243 }
 244
 245 void wxSlider::SetRange( int minValue, int maxValue )
 246 {
 247     double fmin = (double)minValue;
 248     double fmax = (double)maxValue;
 249
 250     if ((fabs(fmin-m_adjust->lower) < 0.2) &&
 251         (fabs(fmax-m_adjust->upper) < 0.2))
 252     {
 253         return;
 254     }
 255
 256     m_adjust->lower = fmin;
 257     m_adjust->upper = fmax;
 258     m_adjust->step_increment = 1.0;
 259     m_adjust->page_increment = ceil((fmax-fmin) / 10.0);
 260
 261     GtkDisableEvents();
 262
 263     gtk_signal_emit_by_name( GTK_OBJECT(m_adjust), "changed" );
 264
 265     GtkEnableEvents();
 266 }
 267
 268 int wxSlider::GetMin() const
 269 {
 270     return (int)ceil(m_adjust->lower);
 271 }
 272
 273 int wxSlider::GetMax() const
 274 {
 275     return (int)ceil(m_adjust->upper);
 276 }
 277
 278 void wxSlider::SetPageSize( int pageSize )
 279 {
 280     double fpage = (double)pageSize;
 281
 282     if (fabs(fpage-m_adjust->page_increment) < 0.2) return;
 283
 284     m_adjust->page_increment = fpage;
 285
 286     GtkDisableEvents();
 287
 288     gtk_signal_emit_by_name( GTK_OBJECT(m_adjust), "changed" );
 289
 290     GtkEnableEvents();
 291 }
 292
 293 int wxSlider::GetPageSize() const
 294 {
 295     return (int)ceil(m_adjust->page_increment);
 296 }
 297
 298 void wxSlider::SetThumbLength( int len )
 299 {
 300     double flen = (double)len;
 301
 302     if (fabs(flen-m_adjust->page_size) < 0.2) return;
 303
 304     m_adjust->page_size = flen;
 305
 306     GtkDisableEvents();
 307
 308     gtk_signal_emit_by_name( GTK_OBJECT(m_adjust), "changed" );
 309
 310     GtkEnableEvents();
 311 }
 312
 313 int wxSlider::GetThumbLength() const
 314 {
 315     return (int)ceil(m_adjust->page_size);
 316 }
 317
 318 void wxSlider::SetLineSize( int WXUNUSED(lineSize) )
 319 {
 320 }
 321
 322 int wxSlider::GetLineSize() const
 323 {
 324     return 0;
 325 }
 326
 327 bool wxSlider::IsOwnGtkWindow( GdkWindow *window )
 328 {
 329     GtkRange *range = GTK_RANGE(m_widget);
 330     return (range->event_window == window);
 331 }
 332
 333 void wxSlider::GtkDisableEvents()
 334 {
 335     gtk_signal_disconnect_by_func( GTK_OBJECT(m_adjust),
 336                         GTK_SIGNAL_FUNC(gtk_slider_callback),
 337                         (gpointer) this );
 338 }
 339
 340 void wxSlider::GtkEnableEvents()
 341 {
 342     gtk_signal_connect( GTK_OBJECT (m_adjust),
 343                         "value_changed",
 344                         GTK_SIGNAL_FUNC(gtk_slider_callback),
 345                         (gpointer) this );
 346 }
 347
 348 // static
 349 wxVisualAttributes
 350 wxSlider::GetClassDefaultAttributes(wxWindowVariant WXUNUSED(variant))
 351 {
 352     return GetDefaultAttributesFromGTKWidget(gtk_vscale_new);
 353 }
 354
 355 #endif