src/gtk/slider.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/gtk/slider.cpp
   3 // Purpose:
   4 // Author:      Robert Roebling
   5 // Copyright:   (c) 1998 Robert Roebling
   6 // Licence:     wxWindows licence
   7 /////////////////////////////////////////////////////////////////////////////
   8
   9 // For compilers that support precompilation, includes "wx.h".
  10 #include "wx/wxprec.h"
  11
  12 #if wxUSE_SLIDER
  13
  14 #include "wx/slider.h"
  15
  16 #ifndef WX_PRECOMP
  17     #include "wx/utils.h"
  18     #include "wx/math.h"
  19 #endif
  20
  21 #include <gtk/gtk.h>
  22 #include "wx/gtk/private/gtk2-compat.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_SLIDER, 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     const double value = gtk_range_get_value(range);
 128     const double oldPos = win->m_pos;
 129     win->m_pos = value;
 130
 131     if (g_blockEventsOnDrag)
 132         return;
 133
 134     if (win->GTKEventsDisabled())
 135     {
 136         win->m_scrollEventType = GTK_SCROLL_NONE;
 137         return;
 138     }
 139
 140     wxEventType eventType = wxEVT_NULL;
 141     if (win->m_isScrolling)
 142     {
 143         eventType = wxEVT_SCROLL_THUMBTRACK;
 144     }
 145     else if (win->m_scrollEventType != GTK_SCROLL_NONE)
 146     {
 147         // Scroll event from "move-slider" (keyboard)
 148         eventType = GtkScrollTypeToWx(win->m_scrollEventType);
 149     }
 150     else if (win->m_mouseButtonDown)
 151     {
 152         // Difference from last change event
 153         const double diff = value - oldPos;
 154         const bool isDown = diff > 0;
 155
 156         GtkAdjustment* adj = gtk_range_get_adjustment(range);
 157         if (IsScrollIncrement(gtk_adjustment_get_page_increment(adj), diff))
 158         {
 159             eventType = isDown ? wxEVT_SCROLL_PAGEDOWN : wxEVT_SCROLL_PAGEUP;
 160         }
 161         else if (wxIsSameDouble(value, 0))
 162         {
 163             eventType = wxEVT_SCROLL_PAGEUP;
 164         }
 165         else if (wxIsSameDouble(value, gtk_adjustment_get_upper(adj)))
 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) != wxRound(value))
 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->GTKDisableEvents();
 235         gtk_range_set_value(GTK_RANGE (win->m_scale), win->GetValue());
 236         win->GTKEnableEvents();
 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 wxSlider::wxSlider()
 276 {
 277     m_scale = NULL;
 278 }
 279
 280 wxSlider::~wxSlider()
 281 {
 282     if (m_scale && m_scale != m_widget)
 283         GTKDisconnect(m_scale);
 284 }
 285
 286 bool wxSlider::Create(wxWindow *parent,
 287                       wxWindowID id,
 288                       int value,
 289                       int minValue,
 290                       int maxValue,
 291                       const wxPoint& pos,
 292                       const wxSize& size,
 293                       long style,
 294                       const wxValidator& validator,
 295                       const wxString& name)
 296 {
 297     m_pos = value;
 298     m_scrollEventType = GTK_SCROLL_NONE;
 299     m_needThumbRelease = false;
 300     m_blockScrollEvent = false;
 301
 302     if (!PreCreation( parent, pos, size ) ||
 303         !CreateBase( parent, id, pos, size, style, validator, name ))
 304     {
 305         wxFAIL_MSG( wxT("wxSlider creation failed") );
 306         return false;
 307     }
 308
 309     const bool isVertical = (style & wxSL_VERTICAL) != 0;
 310     m_scale = gtk_scale_new(GtkOrientation(isVertical), NULL);
 311
 312     if (style & wxSL_MIN_MAX_LABELS)
 313     {
 314         gtk_widget_show( m_scale );
 315
 316         m_widget = gtk_box_new(GtkOrientation(!isVertical), 0);
 317         gtk_box_pack_start(GTK_BOX(m_widget), m_scale, true, true, 0);
 318
 319         GtkWidget* box = gtk_box_new(GtkOrientation(isVertical), 0);
 320         gtk_widget_show(box);
 321         gtk_box_pack_start(GTK_BOX(m_widget), box, true, true, 0);
 322
 323         m_minLabel = gtk_label_new(NULL);
 324         gtk_widget_show( m_minLabel );
 325         gtk_box_pack_start(GTK_BOX(box), m_minLabel, false, false, 0);
 326
 327         // expanding empty space between the min/max labels
 328         GtkWidget *space = gtk_label_new(NULL);
 329         gtk_widget_show( space );
 330         gtk_box_pack_start(GTK_BOX(box), space, true, false, 0);
 331
 332         m_maxLabel = gtk_label_new(NULL);
 333         gtk_widget_show( m_maxLabel );
 334         gtk_box_pack_end(GTK_BOX(box), m_maxLabel, false, false, 0);
 335     }
 336     else
 337     {
 338         m_widget = m_scale;
 339         m_maxLabel = NULL;
 340         m_minLabel = NULL;
 341     }
 342     g_object_ref(m_widget);
 343
 344     const bool showValueLabel = (style & wxSL_VALUE_LABEL) != 0;
 345     gtk_scale_set_draw_value(GTK_SCALE (m_scale), showValueLabel );
 346     if ( showValueLabel )
 347     {
 348         // position the label appropriately: notice that wxSL_DIRECTION flags
 349         // specify the position of the ticks, not label, under MSW and so the
 350         // label is on the opposite side
 351         GtkPositionType posLabel;
 352         if ( style & wxSL_VERTICAL )
 353         {
 354             if ( style & wxSL_LEFT )
 355                 posLabel = GTK_POS_RIGHT;
 356             else // if ( style & wxSL_RIGHT ) -- this is also the default
 357                 posLabel = GTK_POS_LEFT;
 358         }
 359         else // horizontal slider
 360         {
 361             if ( style & wxSL_TOP )
 362                 posLabel = GTK_POS_BOTTOM;
 363             else // if ( style & wxSL_BOTTOM) -- this is again the default
 364                 posLabel = GTK_POS_TOP;
 365         }
 366
 367         gtk_scale_set_value_pos( GTK_SCALE(m_scale), posLabel );
 368     }
 369
 370     // Keep full precision in position value
 371     gtk_scale_set_digits(GTK_SCALE (m_scale), -1);
 372
 373     if (style & wxSL_INVERSE)
 374         gtk_range_set_inverted( GTK_RANGE(m_scale), TRUE );
 375
 376     g_signal_connect(m_scale, "button_press_event", G_CALLBACK(gtk_button_press_event), this);
 377     g_signal_connect(m_scale, "button_release_event", G_CALLBACK(gtk_button_release_event), this);
 378     g_signal_connect(m_scale, "move_slider", G_CALLBACK(gtk_move_slider), this);
 379     g_signal_connect(m_scale, "format_value", G_CALLBACK(gtk_format_value), NULL);
 380     g_signal_connect(m_scale, "value_changed", G_CALLBACK(gtk_value_changed), this);
 381     gulong handler_id = g_signal_connect(m_scale, "event_after", G_CALLBACK(gtk_event_after), this);
 382     g_signal_handler_block(m_scale, handler_id);
 383
 384     SetRange( minValue, maxValue );
 385
 386     // don't call the public SetValue() as it won't do anything unless the
 387     // value really changed
 388     GTKSetValue( value );
 389
 390     m_parent->DoAddChild( this );
 391
 392     PostCreation(size);
 393
 394     return true;
 395 }
 396
 397 void wxSlider::GTKDisableEvents()
 398 {
 399     m_blockScrollEvent = true;
 400 }
 401
 402 void wxSlider::GTKEnableEvents()
 403 {
 404     m_blockScrollEvent = false;
 405 }
 406
 407 bool wxSlider::GTKEventsDisabled() const
 408 {
 409    return m_blockScrollEvent;
 410 }
 411
 412 int wxSlider::GetValue() const
 413 {
 414     return wxRound(m_pos);
 415 }
 416
 417 void wxSlider::SetValue( int value )
 418 {
 419     if (GetValue() != value)
 420         GTKSetValue(value);
 421 }
 422
 423 void wxSlider::GTKSetValue(int value)
 424 {
 425     GTKDisableEvents();
 426     gtk_range_set_value(GTK_RANGE (m_scale), value);
 427     // GTK only updates value label if handle moves at least 1 pixel
 428     gtk_widget_queue_draw(m_scale);
 429     GTKEnableEvents();
 430 }
 431
 432 void wxSlider::SetRange( int minValue, int maxValue )
 433 {
 434     GTKDisableEvents();
 435     if (minValue == maxValue)
 436        maxValue++;
 437     gtk_range_set_range(GTK_RANGE (m_scale), minValue, maxValue);
 438     gtk_range_set_increments(GTK_RANGE (m_scale), 1, (maxValue - minValue + 9) / 10);
 439     GTKEnableEvents();
 440
 441     if (HasFlag(wxSL_MIN_MAX_LABELS))
 442     {
 443         wxString str;
 444
 445         str.Printf( "%d", minValue );
 446         if (HasFlag(wxSL_INVERSE))
 447             gtk_label_set_text( GTK_LABEL(m_maxLabel), str.utf8_str() );
 448         else
 449             gtk_label_set_text( GTK_LABEL(m_minLabel), str.utf8_str() );
 450
 451         str.Printf( "%d", maxValue );
 452         if (HasFlag(wxSL_INVERSE))
 453             gtk_label_set_text( GTK_LABEL(m_minLabel), str.utf8_str() );
 454         else
 455             gtk_label_set_text( GTK_LABEL(m_maxLabel), str.utf8_str() );
 456
 457     }
 458 }
 459
 460 int wxSlider::GetMin() const
 461 {
 462     GtkAdjustment* adj = gtk_range_get_adjustment(GTK_RANGE(m_scale));
 463     return int(gtk_adjustment_get_lower(adj));
 464 }
 465
 466 int wxSlider::GetMax() const
 467 {
 468     GtkAdjustment* adj = gtk_range_get_adjustment(GTK_RANGE(m_scale));
 469     return int(gtk_adjustment_get_upper(adj));
 470 }
 471
 472 void wxSlider::SetPageSize( int pageSize )
 473 {
 474     GTKDisableEvents();
 475     gtk_range_set_increments(GTK_RANGE (m_scale), GetLineSize(), pageSize);
 476     GTKEnableEvents();
 477 }
 478
 479 int wxSlider::GetPageSize() const
 480 {
 481     GtkAdjustment* adj = gtk_range_get_adjustment(GTK_RANGE(m_scale));
 482     return int(gtk_adjustment_get_page_increment(adj));
 483 }
 484
 485 // GTK does not support changing the size of the slider
 486 void wxSlider::SetThumbLength(int)
 487 {
 488 }
 489
 490 int wxSlider::GetThumbLength() const
 491 {
 492     return 0;
 493 }
 494
 495 void wxSlider::SetLineSize( int lineSize )
 496 {
 497     GTKDisableEvents();
 498     gtk_range_set_increments(GTK_RANGE (m_scale), lineSize, GetPageSize());
 499     GTKEnableEvents();
 500 }
 501
 502 int wxSlider::GetLineSize() const
 503 {
 504     GtkAdjustment* adj = gtk_range_get_adjustment(GTK_RANGE(m_scale));
 505     return int(gtk_adjustment_get_step_increment(adj));
 506 }
 507
 508 GdkWindow *wxSlider::GTKGetWindow(wxArrayGdkWindows& WXUNUSED(windows)) const
 509 {
 510 #ifdef __WXGTK3__
 511     // no access to internal GdkWindows
 512     return NULL;
 513 #else
 514     return GTK_RANGE(m_scale)->event_window;
 515 #endif
 516 }
 517
 518 // static
 519 wxVisualAttributes
 520 wxSlider::GetClassDefaultAttributes(wxWindowVariant WXUNUSED(variant))
 521 {
 522     return GetDefaultAttributesFromGTKWidget(gtk_scale_new(GTK_ORIENTATION_VERTICAL, NULL));
 523 }
 524
 525 #endif // wxUSE_SLIDER