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     const int orient = win->HasFlag(wxSL_VERTICAL) ? wxVERTICAL
  56                                                    : wxHORIZONTAL;
  57
  58     const int value = (int)(dvalue < 0 ? dvalue - 0.5 : dvalue + 0.5);
  59
  60     // if we have any "special" event (i.e. the value changed by a line or a
  61     // page), send this specific event first
  62     if ( evtType != wxEVT_NULL )
  63     {
  64         wxScrollEvent event( evtType, win->GetId(), value, orient );
  65         event.SetEventObject( win );
  66         win->GetEventHandler()->ProcessEvent( event );
  67     }
  68
  69     // but, in any case, except if we're dragging the slider (and so the change
  70     // is not definitive), send a generic "changed" event
  71     if ( evtType != wxEVT_SCROLL_THUMBTRACK )
  72     {
  73         wxScrollEvent event(wxEVT_SCROLL_CHANGED, win->GetId(), value, orient);
  74         event.SetEventObject( win );
  75         win->GetEventHandler()->ProcessEvent( event );
  76     }
  77
  78     // and also generate a command event for compatibility
  79     wxCommandEvent event( wxEVT_COMMAND_SLIDER_UPDATED, win->GetId() );
  80     event.SetEventObject( win );
  81     event.SetInt( value );
  82     win->GetEventHandler()->ProcessEvent( event );
  83 }
  84
  85 //-----------------------------------------------------------------------------
  86 // "value_changed"
  87 //-----------------------------------------------------------------------------
  88
  89 extern "C" {
  90 static void gtk_slider_callback( GtkAdjustment *adjust,
  91                                  wxSlider *win )
  92 {
  93     if (g_isIdle) wxapp_install_idle_handler();
  94
  95     if (!win->m_hasVMT) return;
  96     if (g_blockEventsOnDrag) return;
  97
  98     const double dvalue = adjust->value;
  99     const double diff = dvalue - win->m_oldPos;
 100     if ( AreSameAdjustValues(diff, 0) )
 101         return;
 102
 103     wxEventType evtType;
 104     if ( win->m_isScrolling )
 105         evtType = wxEVT_SCROLL_THUMBTRACK;
 106     // it could seem that UP/DOWN are inversed but this is what wxMSW does
 107     else if ( AreSameAdjustValues(diff, adjust->step_increment) )
 108         evtType = wxEVT_SCROLL_LINEDOWN;
 109     else if ( AreSameAdjustValues(diff, -adjust->step_increment) )
 110         evtType = wxEVT_SCROLL_LINEUP;
 111     else if ( AreSameAdjustValues(diff, adjust->page_increment) )
 112         evtType = wxEVT_SCROLL_PAGEDOWN;
 113     else if ( AreSameAdjustValues(diff, -adjust->page_increment) )
 114         evtType = wxEVT_SCROLL_PAGEUP;
 115     else if ( AreSameAdjustValues(adjust->value, adjust->lower) )
 116         evtType = wxEVT_SCROLL_TOP;
 117     else if ( AreSameAdjustValues(adjust->value, adjust->upper) )
 118         evtType = wxEVT_SCROLL_BOTTOM;
 119     else
 120         evtType = wxEVT_NULL; // wxEVT_SCROLL_CHANGED will still be generated
 121
 122     ProcessScrollEvent(win, evtType, dvalue);
 123
 124     win->m_oldPos = dvalue;
 125 }
 126
 127 static gint gtk_slider_button_press_callback( GtkWidget * /* widget */,
 128                                               GdkEventButton * /* gdk_event */,
 129                                               wxWindowGTK *win)
 130 {
 131     // indicate that the thumb is being dragged with the mouse
 132     win->m_isScrolling = true;
 133
 134     return FALSE;
 135 }
 136
 137 static gint gtk_slider_button_release_callback( GtkWidget *scale,
 138                                                 GdkEventButton * /* gdk_event */,
 139                                                 wxSlider *win)
 140 {
 141     // not scrolling any longer
 142     win->m_isScrolling = false;
 143
 144     ProcessScrollEvent(win, wxEVT_SCROLL_THUMBRELEASE,
 145                        GTK_RANGE(scale)->adjustment->value);
 146
 147     return FALSE;
 148 }
 149
 150 }
 151
 152 //-----------------------------------------------------------------------------
 153 // wxSlider
 154 //-----------------------------------------------------------------------------
 155
 156 IMPLEMENT_DYNAMIC_CLASS(wxSlider,wxControl)
 157
 158 bool wxSlider::Create(wxWindow *parent, wxWindowID id,
 159         int value, int minValue, int maxValue,
 160         const wxPoint& pos, const wxSize& size,
 161         long style, const wxValidator& validator, const wxString& name )
 162 {
 163     m_acceptsFocus = TRUE;
 164     m_needParent = TRUE;
 165
 166     if (!PreCreation( parent, pos, size ) ||
 167         !CreateBase( parent, id, pos, size, style, validator, name ))
 168     {
 169         wxFAIL_MSG( wxT("wxSlider creation failed") );
 170         return FALSE;
 171     }
 172
 173     m_oldPos = 0.0;
 174
 175     if (style & wxSL_VERTICAL)
 176         m_widget = gtk_vscale_new( (GtkAdjustment *) NULL );
 177     else
 178         m_widget = gtk_hscale_new( (GtkAdjustment *) NULL );
 179
 180     if (style & wxSL_LABELS)
 181     {
 182         gtk_scale_set_draw_value( GTK_SCALE( m_widget ), TRUE );
 183         gtk_scale_set_digits( GTK_SCALE( m_widget ), 0 );
 184
 185         /* labels need more space and too small window will
 186            cause junk to appear on the dialog */
 187         if (style & wxSL_VERTICAL)
 188         {
 189             wxSize sz( size );
 190             if (sz.x < 35)
 191             {
 192                 sz.x = 35;
 193                 SetSize( sz );
 194             }
 195         }
 196         else
 197         {
 198             wxSize sz( size );
 199             if (sz.y < 35)
 200             {
 201                 sz.y = 35;
 202                 SetSize( sz );
 203             }
 204         }
 205     }
 206     else
 207         gtk_scale_set_draw_value( GTK_SCALE( m_widget ), FALSE );
 208
 209     m_adjust = gtk_range_get_adjustment( GTK_RANGE(m_widget) );
 210
 211     if (style & wxSL_INVERSE)
 212         gtk_range_set_inverted( GTK_RANGE(m_widget), TRUE );
 213
 214     GtkEnableEvents();
 215     g_signal_connect (m_widget, "button_press_event",
 216                       G_CALLBACK (gtk_slider_button_press_callback),
 217                       this);
 218     g_signal_connect (m_widget, "button_release_event",
 219                       G_CALLBACK (gtk_slider_button_release_callback),
 220                       this);
 221
 222     SetRange( minValue, maxValue );
 223     SetValue( value );
 224
 225     m_parent->DoAddChild( this );
 226
 227     PostCreation(size);
 228
 229     return TRUE;
 230 }
 231
 232 int wxSlider::GetValue() const
 233 {
 234     return AdjustValueToInt(m_adjust->value);
 235 }
 236
 237 void wxSlider::SetValue( int value )
 238 {
 239     double fpos = (double)value;
 240     m_oldPos = fpos;
 241     if ( AreSameAdjustValues(fpos, m_adjust->value) )
 242         return;
 243
 244     m_adjust->value = fpos;
 245
 246     GtkDisableEvents();
 247
 248     g_signal_emit_by_name (m_adjust, "value_changed");
 249
 250     GtkEnableEvents();
 251 }
 252
 253 void wxSlider::SetRange( int minValue, int maxValue )
 254 {
 255     double fmin = (double)minValue;
 256     double fmax = (double)maxValue;
 257
 258     if ((fabs(fmin-m_adjust->lower) < 0.2) &&
 259         (fabs(fmax-m_adjust->upper) < 0.2))
 260     {
 261         return;
 262     }
 263
 264     m_adjust->lower = fmin;
 265     m_adjust->upper = fmax;
 266     m_adjust->step_increment = 1.0;
 267     m_adjust->page_increment = ceil((fmax-fmin) / 10.0);
 268
 269     GtkDisableEvents();
 270
 271     g_signal_emit_by_name (m_adjust, "changed");
 272
 273     GtkEnableEvents();
 274 }
 275
 276 int wxSlider::GetMin() const
 277 {
 278     return (int)ceil(m_adjust->lower);
 279 }
 280
 281 int wxSlider::GetMax() const
 282 {
 283     return (int)ceil(m_adjust->upper);
 284 }
 285
 286 void wxSlider::SetPageSize( int pageSize )
 287 {
 288     double fpage = (double)pageSize;
 289
 290     if (fabs(fpage-m_adjust->page_increment) < 0.2) return;
 291
 292     m_adjust->page_increment = fpage;
 293
 294     GtkDisableEvents();
 295
 296     g_signal_emit_by_name (m_adjust, "changed");
 297
 298     GtkEnableEvents();
 299 }
 300
 301 int wxSlider::GetPageSize() const
 302 {
 303     return (int)ceil(m_adjust->page_increment);
 304 }
 305
 306 void wxSlider::SetThumbLength( int len )
 307 {
 308     double flen = (double)len;
 309
 310     if (fabs(flen-m_adjust->page_size) < 0.2) return;
 311
 312     m_adjust->page_size = flen;
 313
 314     GtkDisableEvents();
 315
 316     g_signal_emit_by_name (m_adjust, "changed");
 317
 318     GtkEnableEvents();
 319 }
 320
 321 int wxSlider::GetThumbLength() const
 322 {
 323     return (int)ceil(m_adjust->page_size);
 324 }
 325
 326 void wxSlider::SetLineSize( int WXUNUSED(lineSize) )
 327 {
 328 }
 329
 330 int wxSlider::GetLineSize() const
 331 {
 332     return 0;
 333 }
 334
 335 bool wxSlider::IsOwnGtkWindow( GdkWindow *window )
 336 {
 337     GtkRange *range = GTK_RANGE(m_widget);
 338     return (range->event_window == window);
 339 }
 340
 341 void wxSlider::GtkDisableEvents()
 342 {
 343     g_signal_handlers_disconnect_by_func (m_adjust,
 344                                           (gpointer) gtk_slider_callback,
 345                                           this);
 346 }
 347
 348 void wxSlider::GtkEnableEvents()
 349 {
 350     g_signal_connect (m_adjust, "value_changed",
 351                       G_CALLBACK (gtk_slider_callback), this);
 352 }
 353
 354 // static
 355 wxVisualAttributes
 356 wxSlider::GetClassDefaultAttributes(wxWindowVariant WXUNUSED(variant))
 357 {
 358     return GetDefaultAttributesFromGTKWidget(gtk_vscale_new);
 359 }
 360
 361 #endif