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