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 "wx/gtk/private.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->GetEventHandler()->ProcessEvent( 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->GetEventHandler()->ProcessEvent( 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->GetEventHandler()->ProcessEvent( 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(_T("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     if (g_isIdle) wxapp_install_idle_handler();
 128
 129     GtkAdjustment* adj = gtk_range_get_adjustment (range);
 130     const int pos = wxRound(adj->value);
 131     const double oldPos = win->m_pos;
 132     win->m_pos = adj->value;
 133
 134     if (!win->m_hasVMT || g_blockEventsOnDrag)
 135         return;
 136
 137     if (win->m_blockScrollEvent)
 138     {
 139         win->m_scrollEventType = GTK_SCROLL_NONE;
 140         return;
 141     }
 142
 143     wxEventType eventType = wxEVT_NULL;
 144     if (win->m_isScrolling)
 145     {
 146         eventType = wxEVT_SCROLL_THUMBTRACK;
 147     }
 148     else if (win->m_scrollEventType != GTK_SCROLL_NONE)
 149     {
 150         // Scroll event from "move-slider" (keyboard)
 151         eventType = GtkScrollTypeToWx(win->m_scrollEventType);
 152     }
 153     else if (win->m_mouseButtonDown)
 154     {
 155         // Difference from last change event
 156         const double diff = adj->value - oldPos;
 157         const bool isDown = diff > 0;
 158
 159         if (IsScrollIncrement(adj->page_increment, diff))
 160         {
 161             eventType = isDown ? wxEVT_SCROLL_PAGEDOWN : wxEVT_SCROLL_PAGEUP;
 162         }
 163         else if (wxIsSameDouble(adj->value, 0))
 164         {
 165             eventType = wxEVT_SCROLL_PAGEUP;
 166         }
 167         else if (wxIsSameDouble(adj->value, adj->upper))
 168         {
 169             eventType = wxEVT_SCROLL_PAGEDOWN;
 170         }
 171         else
 172         {
 173             // Assume track event
 174             eventType = wxEVT_SCROLL_THUMBTRACK;
 175             // Remember that we're tracking
 176             win->m_isScrolling = true;
 177         }
 178     }
 179
 180     win->m_scrollEventType = GTK_SCROLL_NONE;
 181
 182     // If integral position has changed
 183     if (wxRound(oldPos) != pos)
 184     {
 185         wxCHECK_RET(eventType != wxEVT_NULL, _T("Unknown slider scroll event type"));
 186         ProcessScrollEvent(win, eventType);
 187         win->m_needThumbRelease = eventType == wxEVT_SCROLL_THUMBTRACK;
 188     }
 189 }
 190 }
 191
 192 //-----------------------------------------------------------------------------
 193 // "move_slider" (keyboard event)
 194 //-----------------------------------------------------------------------------
 195
 196 extern "C" {
 197 static void
 198 gtk_move_slider(GtkRange*, GtkScrollType scrollType, wxSlider* win)
 199 {
 200     // Save keyboard scroll type for "value_changed" handler
 201     win->m_scrollEventType = scrollType;
 202 }
 203 }
 204
 205 //-----------------------------------------------------------------------------
 206 // "button_press_event"
 207 //-----------------------------------------------------------------------------
 208
 209 extern "C" {
 210 static gboolean
 211 gtk_button_press_event(GtkWidget*, GdkEventButton*, wxSlider* win)
 212 {
 213     win->m_mouseButtonDown = true;
 214
 215     return false;
 216 }
 217 }
 218
 219 //-----------------------------------------------------------------------------
 220 // "event_after"
 221 //-----------------------------------------------------------------------------
 222
 223 extern "C" {
 224 static void
 225 gtk_event_after(GtkRange* range, GdkEvent* event, wxSlider* win)
 226 {
 227     if (event->type == GDK_BUTTON_RELEASE)
 228     {
 229         g_signal_handlers_block_by_func(range, (gpointer) gtk_event_after, win);
 230
 231         if (win->m_needThumbRelease)
 232         {
 233             win->m_needThumbRelease = false;
 234             ProcessScrollEvent(win, wxEVT_SCROLL_THUMBRELEASE);
 235         }
 236         // Keep slider at an integral position
 237         win->BlockScrollEvent();
 238         gtk_range_set_value(GTK_RANGE (win->m_widget), win->GetValue());
 239         win->UnblockScrollEvent();
 240     }
 241 }
 242 }
 243
 244 //-----------------------------------------------------------------------------
 245 // "button_release_event"
 246 //-----------------------------------------------------------------------------
 247
 248 extern "C" {
 249 static gboolean
 250 gtk_button_release_event(GtkRange* range, GdkEventButton*, wxSlider* win)
 251 {
 252     win->m_mouseButtonDown = false;
 253     if (win->m_isScrolling)
 254     {
 255         win->m_isScrolling = false;
 256         g_signal_handlers_unblock_by_func(range, (gpointer) gtk_event_after, win);
 257     }
 258     return false;
 259 }
 260 }
 261
 262 //-----------------------------------------------------------------------------
 263 // "format_value"
 264 //-----------------------------------------------------------------------------
 265
 266 extern "C" {
 267 static gchar* gtk_format_value(GtkScale*, double value, void*)
 268 {
 269     // Format value as nearest integer
 270     return g_strdup_printf("%d", wxRound(value));
 271 }
 272 }
 273
 274 //-----------------------------------------------------------------------------
 275 // wxSlider
 276 //-----------------------------------------------------------------------------
 277
 278 IMPLEMENT_DYNAMIC_CLASS(wxSlider,wxControl)
 279
 280 wxSlider::wxSlider()
 281 {
 282     m_pos = 0;
 283     m_scrollEventType = 0;
 284     m_needThumbRelease = false;
 285 }
 286
 287 bool wxSlider::Create(wxWindow *parent, wxWindowID id,
 288         int value, int minValue, int maxValue,
 289         const wxPoint& pos, const wxSize& size,
 290         long style, const wxValidator& validator, const wxString& name )
 291 {
 292     m_acceptsFocus = true;
 293     m_needParent = true;
 294
 295     if (!PreCreation( parent, pos, size ) ||
 296         !CreateBase( parent, id, pos, size, style, validator, name ))
 297     {
 298         wxFAIL_MSG( wxT("wxSlider creation failed") );
 299         return false;
 300     }
 301
 302     m_pos = 0;
 303     m_scrollEventType = 0;
 304     m_needThumbRelease = false;
 305
 306     if (style & wxSL_VERTICAL)
 307         m_widget = gtk_vscale_new( (GtkAdjustment *) NULL );
 308     else
 309         m_widget = gtk_hscale_new( (GtkAdjustment *) NULL );
 310
 311     gtk_scale_set_draw_value(GTK_SCALE (m_widget), (style & wxSL_LABELS) != 0);
 312     // Keep full precision in position value
 313     gtk_scale_set_digits(GTK_SCALE (m_widget), -1);
 314
 315     if (style & wxSL_INVERSE)
 316         gtk_range_set_inverted( GTK_RANGE(m_widget), TRUE );
 317
 318     g_signal_connect(m_widget, "button_press_event", G_CALLBACK(gtk_button_press_event), this);
 319     g_signal_connect(m_widget, "button_release_event", G_CALLBACK(gtk_button_release_event), this);
 320     g_signal_connect(m_widget, "move_slider", G_CALLBACK(gtk_move_slider), this);
 321     g_signal_connect(m_widget, "format_value", G_CALLBACK(gtk_format_value), NULL);
 322     g_signal_connect(m_widget, "value_changed", G_CALLBACK(gtk_value_changed), this);
 323     gulong handler_id;
 324     handler_id = g_signal_connect(
 325         m_widget, "event_after", G_CALLBACK(gtk_event_after), this);
 326     g_signal_handler_block(m_widget, handler_id);
 327
 328     SetRange( minValue, maxValue );
 329     SetValue( value );
 330
 331     m_parent->DoAddChild( this );
 332
 333     PostCreation(size);
 334
 335     return true;
 336 }
 337
 338 int wxSlider::GetValue() const
 339 {
 340     return wxRound(m_pos);
 341 }
 342
 343 void wxSlider::SetValue( int value )
 344 {
 345     if (GetValue() != value)
 346     {
 347         BlockScrollEvent();
 348         gtk_range_set_value(GTK_RANGE (m_widget), value);
 349         UnblockScrollEvent();
 350     }
 351 }
 352
 353 void wxSlider::SetRange( int minValue, int maxValue )
 354 {
 355     BlockScrollEvent();
 356     gtk_range_set_range(GTK_RANGE (m_widget), minValue, maxValue);
 357     gtk_range_set_increments(GTK_RANGE (m_widget), 1, (maxValue - minValue + 9) / 10);
 358     UnblockScrollEvent();
 359 }
 360
 361 int wxSlider::GetMin() const
 362 {
 363     return int(gtk_range_get_adjustment (GTK_RANGE (m_widget))->lower);
 364 }
 365
 366 int wxSlider::GetMax() const
 367 {
 368     return int(gtk_range_get_adjustment (GTK_RANGE (m_widget))->upper);
 369 }
 370
 371 void wxSlider::SetPageSize( int pageSize )
 372 {
 373     BlockScrollEvent();
 374     gtk_range_set_increments(GTK_RANGE (m_widget), GetLineSize(), pageSize);
 375     UnblockScrollEvent();
 376 }
 377
 378 int wxSlider::GetPageSize() const
 379 {
 380     return int(gtk_range_get_adjustment (GTK_RANGE (m_widget))->page_increment);
 381 }
 382
 383 // GTK does not support changing the size of the slider
 384 void wxSlider::SetThumbLength(int)
 385 {
 386 }
 387
 388 int wxSlider::GetThumbLength() const
 389 {
 390     return 0;
 391 }
 392
 393 void wxSlider::SetLineSize( int lineSize )
 394 {
 395     BlockScrollEvent();
 396     gtk_range_set_increments(GTK_RANGE (m_widget), lineSize, GetPageSize());
 397     UnblockScrollEvent();
 398 }
 399
 400 int wxSlider::GetLineSize() const
 401 {
 402     return int(gtk_range_get_adjustment (GTK_RANGE (m_widget))->step_increment);
 403 }
 404
 405 GdkWindow *wxSlider::GTKGetWindow(wxArrayGdkWindows& WXUNUSED(windows)) const
 406 {
 407     return GTK_RANGE(m_widget)->event_window;
 408 }
 409
 410 // static
 411 wxVisualAttributes
 412 wxSlider::GetClassDefaultAttributes(wxWindowVariant WXUNUSED(variant))
 413 {
 414     return GetDefaultAttributesFromGTKWidget(gtk_vscale_new);
 415 }
 416
 417 #endif // wxUSE_SLIDER