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     #include "wx/math.h"
  20 #endif
  21
  22 #include <gtk/gtk.h>
  23
  24 //-----------------------------------------------------------------------------
  25 // data
  26 //-----------------------------------------------------------------------------
  27
  28 extern bool g_blockEventsOnDrag;
  29
  30 // ----------------------------------------------------------------------------
  31 // helper functions
  32 // ----------------------------------------------------------------------------
  33
  34 // process a scroll event
  35 static void
  36 ProcessScrollEvent(wxSlider *win, wxEventType evtType)
  37 {
  38     const int orient = win->HasFlag(wxSL_VERTICAL) ? wxVERTICAL
  39                                                    : wxHORIZONTAL;
  40
  41     const int value = win->GetValue();
  42
  43     // if we have any "special" event (i.e. the value changed by a line or a
  44     // page), send this specific event first
  45     if ( evtType != wxEVT_NULL )
  46     {
  47         wxScrollEvent event( evtType, win->GetId(), value, orient );
  48         event.SetEventObject( win );
  49         win->HandleWindowEvent( event );
  50     }
  51
  52     // but, in any case, except if we're dragging the slider (and so the change
  53     // is not definitive), send a generic "changed" event
  54     if ( evtType != wxEVT_SCROLL_THUMBTRACK )
  55     {
  56         wxScrollEvent event(wxEVT_SCROLL_CHANGED, win->GetId(), value, orient);
  57         event.SetEventObject( win );
  58         win->HandleWindowEvent( event );
  59     }
  60
  61     // and also generate a command event for compatibility
  62     wxCommandEvent event( wxEVT_COMMAND_SLIDER_UPDATED, win->GetId() );
  63     event.SetEventObject( win );
  64     event.SetInt( value );
  65     win->HandleWindowEvent( event );
  66 }
  67
  68 static inline wxEventType GtkScrollTypeToWx(int scrollType)
  69 {
  70     wxEventType eventType;
  71     switch (scrollType)
  72     {
  73     case GTK_SCROLL_STEP_BACKWARD:
  74     case GTK_SCROLL_STEP_LEFT:
  75     case GTK_SCROLL_STEP_UP:
  76         eventType = wxEVT_SCROLL_LINEUP;
  77         break;
  78     case GTK_SCROLL_STEP_DOWN:
  79     case GTK_SCROLL_STEP_FORWARD:
  80     case GTK_SCROLL_STEP_RIGHT:
  81         eventType = wxEVT_SCROLL_LINEDOWN;
  82         break;
  83     case GTK_SCROLL_PAGE_BACKWARD:
  84     case GTK_SCROLL_PAGE_LEFT:
  85     case GTK_SCROLL_PAGE_UP:
  86         eventType = wxEVT_SCROLL_PAGEUP;
  87         break;
  88     case GTK_SCROLL_PAGE_DOWN:
  89     case GTK_SCROLL_PAGE_FORWARD:
  90     case GTK_SCROLL_PAGE_RIGHT:
  91         eventType = wxEVT_SCROLL_PAGEDOWN;
  92         break;
  93     case GTK_SCROLL_START:
  94         eventType = wxEVT_SCROLL_TOP;
  95         break;
  96     case GTK_SCROLL_END:
  97         eventType = wxEVT_SCROLL_BOTTOM;
  98         break;
  99     case GTK_SCROLL_JUMP:
 100         eventType = wxEVT_SCROLL_THUMBTRACK;
 101         break;
 102     default:
 103         wxFAIL_MSG(wxT("Unknown GtkScrollType"));
 104         eventType = wxEVT_NULL;
 105         break;
 106     }
 107     return eventType;
 108 }
 109
 110 // Determine if increment is the same as +/-x, allowing for some small
 111 //   difference due to possible inexactness in floating point arithmetic
 112 static inline bool IsScrollIncrement(double increment, double x)
 113 {
 114     wxASSERT(increment > 0);
 115     const double tolerance = 1.0 / 1024;
 116     return fabs(increment - fabs(x)) < tolerance;
 117 }
 118
 119 //-----------------------------------------------------------------------------
 120 // "value_changed"
 121 //-----------------------------------------------------------------------------
 122
 123 extern "C" {
 124 static void
 125 gtk_value_changed(GtkRange* range, wxSlider* win)
 126 {
 127     GtkAdjustment* adj = gtk_range_get_adjustment (range);
 128     const int pos = wxRound(adj->value);
 129     const double oldPos = win->m_pos;
 130     win->m_pos = adj->value;
 131
 132     if (!win->m_hasVMT || g_blockEventsOnDrag)
 133         return;
 134
 135     if (win->m_blockScrollEvent)
 136     {
 137         win->m_scrollEventType = GTK_SCROLL_NONE;
 138         return;
 139     }
 140
 141     wxEventType eventType = wxEVT_NULL;
 142     if (win->m_isScrolling)
 143     {
 144         eventType = wxEVT_SCROLL_THUMBTRACK;
 145     }
 146     else if (win->m_scrollEventType != GTK_SCROLL_NONE)
 147     {
 148         // Scroll event from "move-slider" (keyboard)
 149         eventType = GtkScrollTypeToWx(win->m_scrollEventType);
 150     }
 151     else if (win->m_mouseButtonDown)
 152     {
 153         // Difference from last change event
 154         const double diff = adj->value - oldPos;
 155         const bool isDown = diff > 0;
 156
 157         if (IsScrollIncrement(adj->page_increment, diff))
 158         {
 159             eventType = isDown ? wxEVT_SCROLL_PAGEDOWN : wxEVT_SCROLL_PAGEUP;
 160         }
 161         else if (wxIsSameDouble(adj->value, 0))
 162         {
 163             eventType = wxEVT_SCROLL_PAGEUP;
 164         }
 165         else if (wxIsSameDouble(adj->value, adj->upper))
 166         {
 167             eventType = wxEVT_SCROLL_PAGEDOWN;
 168         }
 169         else
 170         {
 171             // Assume track event
 172             eventType = wxEVT_SCROLL_THUMBTRACK;
 173             // Remember that we're tracking
 174             win->m_isScrolling = true;
 175         }
 176     }
 177
 178     win->m_scrollEventType = GTK_SCROLL_NONE;
 179
 180     // If integral position has changed
 181     if (wxRound(oldPos) != pos)
 182     {
 183         ProcessScrollEvent(win, eventType);
 184         win->m_needThumbRelease = eventType == wxEVT_SCROLL_THUMBTRACK;
 185     }
 186 }
 187 }
 188
 189 //-----------------------------------------------------------------------------
 190 // "move_slider" (keyboard event)
 191 //-----------------------------------------------------------------------------
 192
 193 extern "C" {
 194 static void
 195 gtk_move_slider(GtkRange*, GtkScrollType scrollType, wxSlider* win)
 196 {
 197     // Save keyboard scroll type for "value_changed" handler
 198     win->m_scrollEventType = scrollType;
 199 }
 200 }
 201
 202 //-----------------------------------------------------------------------------
 203 // "button_press_event"
 204 //-----------------------------------------------------------------------------
 205
 206 extern "C" {
 207 static gboolean
 208 gtk_button_press_event(GtkWidget*, GdkEventButton*, wxSlider* win)
 209 {
 210     win->m_mouseButtonDown = true;
 211
 212     return false;
 213 }
 214 }
 215
 216 //-----------------------------------------------------------------------------
 217 // "event_after"
 218 //-----------------------------------------------------------------------------
 219
 220 extern "C" {
 221 static void
 222 gtk_event_after(GtkRange* range, GdkEvent* event, wxSlider* win)
 223 {
 224     if (event->type == GDK_BUTTON_RELEASE)
 225     {
 226         g_signal_handlers_block_by_func(range, (gpointer) gtk_event_after, win);
 227
 228         if (win->m_needThumbRelease)
 229         {
 230             win->m_needThumbRelease = false;
 231             ProcessScrollEvent(win, wxEVT_SCROLL_THUMBRELEASE);
 232         }
 233         // Keep slider at an integral position
 234         win->m_blockScrollEvent = true;
 235         gtk_range_set_value(GTK_RANGE (win->m_widget), win->GetValue());
 236         win->m_blockScrollEvent = false;
 237     }
 238 }
 239 }
 240
 241 //-----------------------------------------------------------------------------
 242 // "button_release_event"
 243 //-----------------------------------------------------------------------------
 244
 245 extern "C" {
 246 static gboolean
 247 gtk_button_release_event(GtkRange* range, GdkEventButton*, wxSlider* win)
 248 {
 249     win->m_mouseButtonDown = false;
 250     if (win->m_isScrolling)
 251     {
 252         win->m_isScrolling = false;
 253         g_signal_handlers_unblock_by_func(range, (gpointer) gtk_event_after, win);
 254     }
 255     return false;
 256 }
 257 }
 258
 259 //-----------------------------------------------------------------------------
 260 // "format_value"
 261 //-----------------------------------------------------------------------------
 262
 263 extern "C" {
 264 static gchar* gtk_format_value(GtkScale*, double value, void*)
 265 {
 266     // Format value as nearest integer
 267     return g_strdup_printf("%d", wxRound(value));
 268 }
 269 }
 270
 271 //-----------------------------------------------------------------------------
 272 // wxSlider
 273 //-----------------------------------------------------------------------------
 274
 275 IMPLEMENT_DYNAMIC_CLASS(wxSlider,wxControl)
 276
 277 wxSlider::wxSlider()
 278 {
 279     m_pos = 0;
 280     m_scrollEventType = GTK_SCROLL_NONE;
 281     m_needThumbRelease = false;
 282     m_blockScrollEvent = false;
 283 }
 284
 285 bool wxSlider::Create(wxWindow *parent,
 286                       wxWindowID id,
 287                       int value,
 288                       int minValue,
 289                       int maxValue,
 290                       const wxPoint& pos,
 291                       const wxSize& size,
 292                       long style,
 293                       const wxValidator& validator,
 294                       const wxString& name)
 295 {
 296     m_pos = value;
 297     m_scrollEventType = GTK_SCROLL_NONE;
 298
 299     if (!PreCreation( parent, pos, size ) ||
 300         !CreateBase( parent, id, pos, size, style, validator, name ))
 301     {
 302         wxFAIL_MSG( wxT("wxSlider creation failed") );
 303         return false;
 304     }
 305
 306     if (style & wxSL_VERTICAL)
 307         m_widget = gtk_vscale_new( NULL );
 308     else
 309         m_widget = gtk_hscale_new( NULL );
 310     g_object_ref(m_widget);
 311
 312     gtk_scale_set_draw_value(GTK_SCALE (m_widget), (style & wxSL_LABELS) != 0);
 313     // Keep full precision in position value
 314     gtk_scale_set_digits(GTK_SCALE (m_widget), -1);
 315
 316     if (style & wxSL_INVERSE)
 317         gtk_range_set_inverted( GTK_RANGE(m_widget), TRUE );
 318
 319     g_signal_connect(m_widget, "button_press_event", G_CALLBACK(gtk_button_press_event), this);
 320     g_signal_connect(m_widget, "button_release_event", G_CALLBACK(gtk_button_release_event), this);
 321     g_signal_connect(m_widget, "move_slider", G_CALLBACK(gtk_move_slider), this);
 322     g_signal_connect(m_widget, "format_value", G_CALLBACK(gtk_format_value), NULL);
 323     g_signal_connect(m_widget, "value_changed", G_CALLBACK(gtk_value_changed), this);
 324     gulong handler_id = g_signal_connect(m_widget, "event_after", G_CALLBACK(gtk_event_after), this);
 325     g_signal_handler_block(m_widget, handler_id);
 326
 327     SetRange( minValue, maxValue );
 328
 329     // don't call the public SetValue() as it won't do anything unless the
 330     // value really changed
 331     GTKSetValue( value );
 332
 333     m_parent->DoAddChild( this );
 334
 335     PostCreation(size);
 336
 337     return true;
 338 }
 339
 340 int wxSlider::GetValue() const
 341 {
 342     return wxRound(m_pos);
 343 }
 344
 345 void wxSlider::SetValue( int value )
 346 {
 347     if (GetValue() != value)
 348         GTKSetValue(value);
 349 }
 350
 351 void wxSlider::GTKSetValue(int value)
 352 {
 353     m_blockScrollEvent = true;
 354     gtk_range_set_value(GTK_RANGE (m_widget), value);
 355     m_blockScrollEvent = false;
 356 }
 357
 358 void wxSlider::SetRange( int minValue, int maxValue )
 359 {
 360     m_blockScrollEvent = true;
 361     if (minValue == maxValue)
 362        maxValue++;
 363     gtk_range_set_range(GTK_RANGE (m_widget), minValue, maxValue);
 364     gtk_range_set_increments(GTK_RANGE (m_widget), 1, (maxValue - minValue + 9) / 10);
 365     m_blockScrollEvent = false;
 366 }
 367
 368 int wxSlider::GetMin() const
 369 {
 370     return int(gtk_range_get_adjustment (GTK_RANGE (m_widget))->lower);
 371 }
 372
 373 int wxSlider::GetMax() const
 374 {
 375     return int(gtk_range_get_adjustment (GTK_RANGE (m_widget))->upper);
 376 }
 377
 378 void wxSlider::SetPageSize( int pageSize )
 379 {
 380     m_blockScrollEvent = true;
 381     gtk_range_set_increments(GTK_RANGE (m_widget), GetLineSize(), pageSize);
 382     m_blockScrollEvent = false;
 383 }
 384
 385 int wxSlider::GetPageSize() const
 386 {
 387     return int(gtk_range_get_adjustment (GTK_RANGE (m_widget))->page_increment);
 388 }
 389
 390 // GTK does not support changing the size of the slider
 391 void wxSlider::SetThumbLength(int)
 392 {
 393 }
 394
 395 int wxSlider::GetThumbLength() const
 396 {
 397     return 0;
 398 }
 399
 400 void wxSlider::SetLineSize( int lineSize )
 401 {
 402     m_blockScrollEvent = true;
 403     gtk_range_set_increments(GTK_RANGE (m_widget), lineSize, GetPageSize());
 404     m_blockScrollEvent = false;
 405 }
 406
 407 int wxSlider::GetLineSize() const
 408 {
 409     return int(gtk_range_get_adjustment (GTK_RANGE (m_widget))->step_increment);
 410 }
 411
 412 GdkWindow *wxSlider::GTKGetWindow(wxArrayGdkWindows& WXUNUSED(windows)) const
 413 {
 414     return GTK_RANGE(m_widget)->event_window;
 415 }
 416
 417 // static
 418 wxVisualAttributes
 419 wxSlider::GetClassDefaultAttributes(wxWindowVariant WXUNUSED(variant))
 420 {
 421     return GetDefaultAttributesFromGTKWidget(gtk_vscale_new);
 422 }
 423
 424 #endif // wxUSE_SLIDER