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 #include "wx/gtk/private/gtk2-compat.h"
  24
  25 //-----------------------------------------------------------------------------
  26 // data
  27 //-----------------------------------------------------------------------------
  28
  29 extern bool g_blockEventsOnDrag;
  30
  31 // ----------------------------------------------------------------------------
  32 // helper functions
  33 // ----------------------------------------------------------------------------
  34
  35 // process a scroll event
  36 static void
  37 ProcessScrollEvent(wxSlider *win, wxEventType evtType)
  38 {
  39     const int orient = win->HasFlag(wxSL_VERTICAL) ? wxVERTICAL
  40                                                    : wxHORIZONTAL;
  41
  42     const int value = win->GetValue();
  43
  44     // if we have any "special" event (i.e. the value changed by a line or a
  45     // page), send this specific event first
  46     if ( evtType != wxEVT_NULL )
  47     {
  48         wxScrollEvent event( evtType, win->GetId(), value, orient );
  49         event.SetEventObject( win );
  50         win->HandleWindowEvent( event );
  51     }
  52
  53     // but, in any case, except if we're dragging the slider (and so the change
  54     // is not definitive), send a generic "changed" event
  55     if ( evtType != wxEVT_SCROLL_THUMBTRACK )
  56     {
  57         wxScrollEvent event(wxEVT_SCROLL_CHANGED, win->GetId(), value, orient);
  58         event.SetEventObject( win );
  59         win->HandleWindowEvent( event );
  60     }
  61
  62     // and also generate a command event for compatibility
  63     wxCommandEvent event( wxEVT_COMMAND_SLIDER_UPDATED, win->GetId() );
  64     event.SetEventObject( win );
  65     event.SetInt( value );
  66     win->HandleWindowEvent( event );
  67 }
  68
  69 static inline wxEventType GtkScrollTypeToWx(int scrollType)
  70 {
  71     wxEventType eventType;
  72     switch (scrollType)
  73     {
  74     case GTK_SCROLL_STEP_BACKWARD:
  75     case GTK_SCROLL_STEP_LEFT:
  76     case GTK_SCROLL_STEP_UP:
  77         eventType = wxEVT_SCROLL_LINEUP;
  78         break;
  79     case GTK_SCROLL_STEP_DOWN:
  80     case GTK_SCROLL_STEP_FORWARD:
  81     case GTK_SCROLL_STEP_RIGHT:
  82         eventType = wxEVT_SCROLL_LINEDOWN;
  83         break;
  84     case GTK_SCROLL_PAGE_BACKWARD:
  85     case GTK_SCROLL_PAGE_LEFT:
  86     case GTK_SCROLL_PAGE_UP:
  87         eventType = wxEVT_SCROLL_PAGEUP;
  88         break;
  89     case GTK_SCROLL_PAGE_DOWN:
  90     case GTK_SCROLL_PAGE_FORWARD:
  91     case GTK_SCROLL_PAGE_RIGHT:
  92         eventType = wxEVT_SCROLL_PAGEDOWN;
  93         break;
  94     case GTK_SCROLL_START:
  95         eventType = wxEVT_SCROLL_TOP;
  96         break;
  97     case GTK_SCROLL_END:
  98         eventType = wxEVT_SCROLL_BOTTOM;
  99         break;
 100     case GTK_SCROLL_JUMP:
 101         eventType = wxEVT_SCROLL_THUMBTRACK;
 102         break;
 103     default:
 104         wxFAIL_MSG(wxT("Unknown GtkScrollType"));
 105         eventType = wxEVT_NULL;
 106         break;
 107     }
 108     return eventType;
 109 }
 110
 111 // Determine if increment is the same as +/-x, allowing for some small
 112 //   difference due to possible inexactness in floating point arithmetic
 113 static inline bool IsScrollIncrement(double increment, double x)
 114 {
 115     wxASSERT(increment > 0);
 116     const double tolerance = 1.0 / 1024;
 117     return fabs(increment - fabs(x)) < tolerance;
 118 }
 119
 120 //-----------------------------------------------------------------------------
 121 // "value_changed"
 122 //-----------------------------------------------------------------------------
 123
 124 extern "C" {
 125 static void
 126 gtk_value_changed(GtkRange* range, wxSlider* win)
 127 {
 128     const double value = gtk_range_get_value(range);
 129     const double oldPos = win->m_pos;
 130     win->m_pos = value;
 131
 132     if (!win->m_hasVMT || g_blockEventsOnDrag)
 133         return;
 134
 135     if (win->GTKEventsDisabled())
 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 = value - oldPos;
 155         const bool isDown = diff > 0;
 156
 157         GtkAdjustment* adj = gtk_range_get_adjustment(range);
 158         if (IsScrollIncrement(gtk_adjustment_get_page_increment(adj), diff))
 159         {
 160             eventType = isDown ? wxEVT_SCROLL_PAGEDOWN : wxEVT_SCROLL_PAGEUP;
 161         }
 162         else if (wxIsSameDouble(value, 0))
 163         {
 164             eventType = wxEVT_SCROLL_PAGEUP;
 165         }
 166         else if (wxIsSameDouble(value, gtk_adjustment_get_upper(adj)))
 167         {
 168             eventType = wxEVT_SCROLL_PAGEDOWN;
 169         }
 170         else
 171         {
 172             // Assume track event
 173             eventType = wxEVT_SCROLL_THUMBTRACK;
 174             // Remember that we're tracking
 175             win->m_isScrolling = true;
 176         }
 177     }
 178
 179     win->m_scrollEventType = GTK_SCROLL_NONE;
 180
 181     // If integral position has changed
 182     if (wxRound(oldPos) != wxRound(value))
 183     {
 184         ProcessScrollEvent(win, eventType);
 185         win->m_needThumbRelease = eventType == wxEVT_SCROLL_THUMBTRACK;
 186     }
 187 }
 188 }
 189
 190 //-----------------------------------------------------------------------------
 191 // "move_slider" (keyboard event)
 192 //-----------------------------------------------------------------------------
 193
 194 extern "C" {
 195 static void
 196 gtk_move_slider(GtkRange*, GtkScrollType scrollType, wxSlider* win)
 197 {
 198     // Save keyboard scroll type for "value_changed" handler
 199     win->m_scrollEventType = scrollType;
 200 }
 201 }
 202
 203 //-----------------------------------------------------------------------------
 204 // "button_press_event"
 205 //-----------------------------------------------------------------------------
 206
 207 extern "C" {
 208 static gboolean
 209 gtk_button_press_event(GtkWidget*, GdkEventButton*, wxSlider* win)
 210 {
 211     win->m_mouseButtonDown = true;
 212
 213     return false;
 214 }
 215 }
 216
 217 //-----------------------------------------------------------------------------
 218 // "event_after"
 219 //-----------------------------------------------------------------------------
 220
 221 extern "C" {
 222 static void
 223 gtk_event_after(GtkRange* range, GdkEvent* event, wxSlider* win)
 224 {
 225     if (event->type == GDK_BUTTON_RELEASE)
 226     {
 227         g_signal_handlers_block_by_func(range, (gpointer) gtk_event_after, win);
 228
 229         if (win->m_needThumbRelease)
 230         {
 231             win->m_needThumbRelease = false;
 232             ProcessScrollEvent(win, wxEVT_SCROLL_THUMBRELEASE);
 233         }
 234         // Keep slider at an integral position
 235         win->GTKDisableEvents();
 236         gtk_range_set_value(GTK_RANGE (win->m_scale), win->GetValue());
 237         win->GTKEnableEvents();
 238     }
 239 }
 240 }
 241
 242 //-----------------------------------------------------------------------------
 243 // "button_release_event"
 244 //-----------------------------------------------------------------------------
 245
 246 extern "C" {
 247 static gboolean
 248 gtk_button_release_event(GtkRange* range, GdkEventButton*, wxSlider* win)
 249 {
 250     win->m_mouseButtonDown = false;
 251     if (win->m_isScrolling)
 252     {
 253         win->m_isScrolling = false;
 254         g_signal_handlers_unblock_by_func(range, (gpointer) gtk_event_after, win);
 255     }
 256     return false;
 257 }
 258 }
 259
 260 //-----------------------------------------------------------------------------
 261 // "format_value"
 262 //-----------------------------------------------------------------------------
 263
 264 extern "C" {
 265 static gchar* gtk_format_value(GtkScale*, double value, void*)
 266 {
 267     // Format value as nearest integer
 268     return g_strdup_printf("%d", wxRound(value));
 269 }
 270 }
 271
 272 //-----------------------------------------------------------------------------
 273 // wxSlider
 274 //-----------------------------------------------------------------------------
 275
 276 wxSlider::wxSlider()
 277 {
 278     m_pos = 0;
 279     m_scrollEventType = GTK_SCROLL_NONE;
 280     m_needThumbRelease = false;
 281     m_blockScrollEvent = false;
 282 }
 283
 284 bool wxSlider::Create(wxWindow *parent,
 285                       wxWindowID id,
 286                       int value,
 287                       int minValue,
 288                       int maxValue,
 289                       const wxPoint& pos,
 290                       const wxSize& size,
 291                       long style,
 292                       const wxValidator& validator,
 293                       const wxString& name)
 294 {
 295     m_pos = value;
 296     m_scrollEventType = GTK_SCROLL_NONE;
 297
 298     if (!PreCreation( parent, pos, size ) ||
 299         !CreateBase( parent, id, pos, size, style, validator, name ))
 300     {
 301         wxFAIL_MSG( wxT("wxSlider creation failed") );
 302         return false;
 303     }
 304
 305
 306     if (style & wxSL_VERTICAL)
 307         m_scale = gtk_vscale_new( NULL );
 308     else
 309         m_scale = gtk_hscale_new( NULL );
 310     g_object_ref(m_scale);
 311
 312     if (style & wxSL_MIN_MAX_LABELS)
 313     {
 314         gtk_widget_show( m_scale );
 315
 316         if (style & wxSL_VERTICAL)
 317             m_widget = gtk_hbox_new(false, 0);
 318         else
 319             m_widget = gtk_vbox_new(false, 0);
 320         g_object_ref(m_widget);
 321         gtk_container_add( GTK_CONTAINER(m_widget), m_scale );
 322
 323         GtkWidget *box;
 324         if (style & wxSL_VERTICAL)
 325             box = gtk_vbox_new(false,0);
 326         else
 327             box = gtk_hbox_new(false,0);
 328         g_object_ref(box);
 329         gtk_widget_show(box);
 330         gtk_container_add( GTK_CONTAINER(m_widget), box );
 331
 332         m_minLabel = gtk_label_new(NULL);
 333         g_object_ref(m_minLabel);
 334         gtk_widget_show( m_minLabel );
 335         gtk_container_add( GTK_CONTAINER(box), m_minLabel );
 336         gtk_box_set_child_packing( GTK_BOX(box), m_minLabel, FALSE, FALSE, 0, GTK_PACK_START );
 337
 338         // expanding empty space between the min/max labels
 339         GtkWidget *space = gtk_label_new(NULL);
 340         g_object_ref(space);
 341         gtk_widget_show( space );
 342         gtk_container_add( GTK_CONTAINER(box), space );
 343         gtk_box_set_child_packing( GTK_BOX(box), space, TRUE, FALSE, 0, GTK_PACK_START );
 344
 345         m_maxLabel = gtk_label_new(NULL);
 346         g_object_ref(m_maxLabel);
 347         gtk_widget_show( m_maxLabel );
 348         gtk_container_add( GTK_CONTAINER(box), m_maxLabel );
 349         gtk_box_set_child_packing( GTK_BOX(box), m_maxLabel, FALSE, FALSE, 0, GTK_PACK_END );
 350     }
 351     else
 352     {
 353         m_widget = m_scale;
 354         m_maxLabel = NULL;
 355         m_minLabel = NULL;
 356     }
 357
 358     const bool showValueLabel = (style & wxSL_VALUE_LABEL) != 0;
 359     gtk_scale_set_draw_value(GTK_SCALE (m_scale), showValueLabel );
 360     if ( showValueLabel )
 361     {
 362         // position the label appropriately: notice that wxSL_DIRECTION flags
 363         // specify the position of the ticks, not label, under MSW and so the
 364         // label is on the opposite side
 365         GtkPositionType posLabel;
 366         if ( style & wxSL_VERTICAL )
 367         {
 368             if ( style & wxSL_LEFT )
 369                 posLabel = GTK_POS_RIGHT;
 370             else // if ( style & wxSL_RIGHT ) -- this is also the default
 371                 posLabel = GTK_POS_LEFT;
 372         }
 373         else // horizontal slider
 374         {
 375             if ( style & wxSL_TOP )
 376                 posLabel = GTK_POS_BOTTOM;
 377             else // if ( style & wxSL_BOTTOM) -- this is again the default
 378                 posLabel = GTK_POS_TOP;
 379         }
 380
 381         gtk_scale_set_value_pos( GTK_SCALE(m_scale), posLabel );
 382     }
 383
 384     // Keep full precision in position value
 385     gtk_scale_set_digits(GTK_SCALE (m_scale), -1);
 386
 387     if (style & wxSL_INVERSE)
 388         gtk_range_set_inverted( GTK_RANGE(m_scale), TRUE );
 389
 390     g_signal_connect(m_scale, "button_press_event", G_CALLBACK(gtk_button_press_event), this);
 391     g_signal_connect(m_scale, "button_release_event", G_CALLBACK(gtk_button_release_event), this);
 392     g_signal_connect(m_scale, "move_slider", G_CALLBACK(gtk_move_slider), this);
 393     g_signal_connect(m_scale, "format_value", G_CALLBACK(gtk_format_value), NULL);
 394     g_signal_connect(m_scale, "value_changed", G_CALLBACK(gtk_value_changed), this);
 395     gulong handler_id = g_signal_connect(m_scale, "event_after", G_CALLBACK(gtk_event_after), this);
 396     g_signal_handler_block(m_scale, handler_id);
 397
 398     SetRange( minValue, maxValue );
 399
 400     // don't call the public SetValue() as it won't do anything unless the
 401     // value really changed
 402     GTKSetValue( value );
 403
 404     m_parent->DoAddChild( this );
 405
 406     PostCreation(size);
 407
 408     return true;
 409 }
 410
 411 void wxSlider::GTKDisableEvents()
 412 {
 413     m_blockScrollEvent = true;
 414 }
 415
 416 void wxSlider::GTKEnableEvents()
 417 {
 418     m_blockScrollEvent = false;
 419 }
 420
 421 bool wxSlider::GTKEventsDisabled() const
 422 {
 423    return m_blockScrollEvent;
 424 }
 425
 426 int wxSlider::GetValue() const
 427 {
 428     return wxRound(m_pos);
 429 }
 430
 431 void wxSlider::SetValue( int value )
 432 {
 433     if (GetValue() != value)
 434         GTKSetValue(value);
 435 }
 436
 437 void wxSlider::GTKSetValue(int value)
 438 {
 439     GTKDisableEvents();
 440     gtk_range_set_value(GTK_RANGE (m_scale), value);
 441     // GTK only updates value label if handle moves at least 1 pixel
 442     gtk_widget_queue_draw(m_scale);
 443     GTKEnableEvents();
 444 }
 445
 446 void wxSlider::SetRange( int minValue, int maxValue )
 447 {
 448     GTKDisableEvents();
 449     if (minValue == maxValue)
 450        maxValue++;
 451     gtk_range_set_range(GTK_RANGE (m_scale), minValue, maxValue);
 452     gtk_range_set_increments(GTK_RANGE (m_scale), 1, (maxValue - minValue + 9) / 10);
 453     GTKEnableEvents();
 454
 455     if (HasFlag(wxSL_MIN_MAX_LABELS))
 456     {
 457         wxString str;
 458
 459         str.Printf( "%d", minValue );
 460         if (HasFlag(wxSL_INVERSE))
 461             gtk_label_set_text( GTK_LABEL(m_maxLabel), str.utf8_str() );
 462         else
 463             gtk_label_set_text( GTK_LABEL(m_minLabel), str.utf8_str() );
 464
 465         str.Printf( "%d", maxValue );
 466         if (HasFlag(wxSL_INVERSE))
 467             gtk_label_set_text( GTK_LABEL(m_minLabel), str.utf8_str() );
 468         else
 469             gtk_label_set_text( GTK_LABEL(m_maxLabel), str.utf8_str() );
 470
 471     }
 472 }
 473
 474 int wxSlider::GetMin() const
 475 {
 476     GtkAdjustment* adj = gtk_range_get_adjustment(GTK_RANGE(m_scale));
 477     return int(gtk_adjustment_get_lower(adj));
 478 }
 479
 480 int wxSlider::GetMax() const
 481 {
 482     GtkAdjustment* adj = gtk_range_get_adjustment(GTK_RANGE(m_scale));
 483     return int(gtk_adjustment_get_upper(adj));
 484 }
 485
 486 void wxSlider::SetPageSize( int pageSize )
 487 {
 488     GTKDisableEvents();
 489     gtk_range_set_increments(GTK_RANGE (m_scale), GetLineSize(), pageSize);
 490     GTKEnableEvents();
 491 }
 492
 493 int wxSlider::GetPageSize() const
 494 {
 495     GtkAdjustment* adj = gtk_range_get_adjustment(GTK_RANGE(m_scale));
 496     return int(gtk_adjustment_get_page_increment(adj));
 497 }
 498
 499 // GTK does not support changing the size of the slider
 500 void wxSlider::SetThumbLength(int)
 501 {
 502 }
 503
 504 int wxSlider::GetThumbLength() const
 505 {
 506     return 0;
 507 }
 508
 509 void wxSlider::SetLineSize( int lineSize )
 510 {
 511     GTKDisableEvents();
 512     gtk_range_set_increments(GTK_RANGE (m_scale), lineSize, GetPageSize());
 513     GTKEnableEvents();
 514 }
 515
 516 int wxSlider::GetLineSize() const
 517 {
 518     GtkAdjustment* adj = gtk_range_get_adjustment(GTK_RANGE(m_scale));
 519     return int(gtk_adjustment_get_step_increment(adj));
 520 }
 521
 522 GdkWindow *wxSlider::GTKGetWindow(wxArrayGdkWindows& WXUNUSED(windows)) const
 523 {
 524     return GTK_RANGE(m_scale)->event_window;
 525 }
 526
 527 // static
 528 wxVisualAttributes
 529 wxSlider::GetClassDefaultAttributes(wxWindowVariant WXUNUSED(variant))
 530 {
 531     return GetDefaultAttributesFromGTKWidget(gtk_vscale_new);
 532 }
 533
 534 #endif // wxUSE_SLIDER