1/////////////////////////////////////////////////////////////////////////////
2// Name:        src/gtk/slider.cpp
3// Purpose:
4// Author:      Robert Roebling
5// Id:          $Id: slider.cpp 44603 2007-03-03 18:37:08Z PC $
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
28extern bool g_blockEventsOnDrag;
29
30// ----------------------------------------------------------------------------
31// helper functions
32// ----------------------------------------------------------------------------
33
34// process a scroll event
35static void
36ProcessScrollEvent(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
68static 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
112static 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
123extern "C" {
124static void
125gtk_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        ProcessScrollEvent(win, eventType);
186        win->m_needThumbRelease = eventType == wxEVT_SCROLL_THUMBTRACK;
187    }
188}
189}
190
191//-----------------------------------------------------------------------------
192// "move_slider" (keyboard event)
193//-----------------------------------------------------------------------------
194
195extern "C" {
196static void
197gtk_move_slider(GtkRange*, GtkScrollType scrollType, wxSlider* win)
198{
199    // Save keyboard scroll type for "value_changed" handler
200    win->m_scrollEventType = scrollType;
201}
202}
203
204//-----------------------------------------------------------------------------
205// "button_press_event"
206//-----------------------------------------------------------------------------
207
208extern "C" {
209static gboolean
210gtk_button_press_event(GtkWidget*, GdkEventButton*, wxSlider* win)
211{
212    win->m_mouseButtonDown = true;
213
214    return false;
215}
216}
217
218//-----------------------------------------------------------------------------
219// "event_after"
220//-----------------------------------------------------------------------------
221
222extern "C" {
223static void
224gtk_event_after(GtkRange* range, GdkEvent* event, wxSlider* win)
225{
226    if (event->type == GDK_BUTTON_RELEASE)
227    {
228        g_signal_handlers_block_by_func(range, (gpointer) gtk_event_after, win);
229
230        if (win->m_needThumbRelease)
231        {
232            win->m_needThumbRelease = false;
233            ProcessScrollEvent(win, wxEVT_SCROLL_THUMBRELEASE);
234        }
235        // Keep slider at an integral position
236        win->BlockScrollEvent();
237        gtk_range_set_value(GTK_RANGE (win->m_widget), win->GetValue());
238        win->UnblockScrollEvent();
239    }
240}
241}
242
243//-----------------------------------------------------------------------------
244// "button_release_event"
245//-----------------------------------------------------------------------------
246
247extern "C" {
248static gboolean
249gtk_button_release_event(GtkRange* range, GdkEventButton*, wxSlider* win)
250{
251    win->m_mouseButtonDown = false;
252    if (win->m_isScrolling)
253    {
254        win->m_isScrolling = false;
255        g_signal_handlers_unblock_by_func(range, (gpointer) gtk_event_after, win);
256    }
257    return false;
258}
259}
260
261//-----------------------------------------------------------------------------
262// "format_value"
263//-----------------------------------------------------------------------------
264
265extern "C" {
266static gchar* gtk_format_value(GtkScale*, double value, void*)
267{
268    // Format value as nearest integer
269    return g_strdup_printf("%d", wxRound(value));
270}
271}
272
273//-----------------------------------------------------------------------------
274// wxSlider
275//-----------------------------------------------------------------------------
276
277IMPLEMENT_DYNAMIC_CLASS(wxSlider,wxControl)
278
279wxSlider::wxSlider()
280{
281    m_pos = 0;
282    m_scrollEventType = 0;
283    m_needThumbRelease = false;
284}
285
286bool wxSlider::Create(wxWindow *parent, wxWindowID id,
287        int value, int minValue, int maxValue,
288        const wxPoint& pos, const wxSize& size,
289        long style, const wxValidator& validator, const wxString& name )
290{
291    m_acceptsFocus = true;
292    m_needParent = true;
293
294    if (!PreCreation( parent, pos, size ) ||
295        !CreateBase( parent, id, pos, size, style, validator, name ))
296    {
297        wxFAIL_MSG( wxT("wxSlider creation failed") );
298        return false;
299    }
300
301    m_pos = 0;
302    m_scrollEventType = 0;
303    m_needThumbRelease = false;
304
305    if (style & wxSL_VERTICAL)
306        m_widget = gtk_vscale_new( (GtkAdjustment *) NULL );
307    else
308        m_widget = gtk_hscale_new( (GtkAdjustment *) NULL );
309
310    gtk_scale_set_draw_value(GTK_SCALE (m_widget), (style & wxSL_LABELS) != 0);
311    // Keep full precision in position value
312    gtk_scale_set_digits(GTK_SCALE (m_widget), -1);
313
314    if (style & wxSL_INVERSE)
315        gtk_range_set_inverted( GTK_RANGE(m_widget), TRUE );
316
317    g_signal_connect(m_widget, "button_press_event", G_CALLBACK(gtk_button_press_event), this);
318    g_signal_connect(m_widget, "button_release_event", G_CALLBACK(gtk_button_release_event), this);
319    g_signal_connect(m_widget, "move_slider", G_CALLBACK(gtk_move_slider), this);
320    g_signal_connect(m_widget, "format_value", G_CALLBACK(gtk_format_value), NULL);
321    g_signal_connect(m_widget, "value_changed", G_CALLBACK(gtk_value_changed), this);
322    gulong handler_id;
323    handler_id = g_signal_connect(
324        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    SetValue( value );
329
330    m_parent->DoAddChild( this );
331
332    PostCreation(size);
333
334    return true;
335}
336
337int wxSlider::GetValue() const
338{
339    return wxRound(m_pos);
340}
341
342void wxSlider::SetValue( int value )
343{
344    if (GetValue() != value)
345    {
346        BlockScrollEvent();
347        gtk_range_set_value(GTK_RANGE (m_widget), value);
348        UnblockScrollEvent();
349    }
350}
351
352void wxSlider::SetRange( int minValue, int maxValue )
353{
354    BlockScrollEvent();
355    gtk_range_set_range(GTK_RANGE (m_widget), minValue, maxValue);
356    gtk_range_set_increments(GTK_RANGE (m_widget), 1, (maxValue - minValue + 9) / 10);
357    UnblockScrollEvent();
358}
359
360int wxSlider::GetMin() const
361{
362    return int(gtk_range_get_adjustment (GTK_RANGE (m_widget))->lower);
363}
364
365int wxSlider::GetMax() const
366{
367    return int(gtk_range_get_adjustment (GTK_RANGE (m_widget))->upper);
368}
369
370void wxSlider::SetPageSize( int pageSize )
371{
372    BlockScrollEvent();
373    gtk_range_set_increments(GTK_RANGE (m_widget), GetLineSize(), pageSize);
374    UnblockScrollEvent();
375}
376
377int wxSlider::GetPageSize() const
378{
379    return int(gtk_range_get_adjustment (GTK_RANGE (m_widget))->page_increment);
380}
381
382// GTK does not support changing the size of the slider
383void wxSlider::SetThumbLength(int)
384{
385}
386
387int wxSlider::GetThumbLength() const
388{
389    return 0;
390}
391
392void wxSlider::SetLineSize( int lineSize )
393{
394    BlockScrollEvent();
395    gtk_range_set_increments(GTK_RANGE (m_widget), lineSize, GetPageSize());
396    UnblockScrollEvent();
397}
398
399int wxSlider::GetLineSize() const
400{
401    return int(gtk_range_get_adjustment (GTK_RANGE (m_widget))->step_increment);
402}
403
404GdkWindow *wxSlider::GTKGetWindow(wxArrayGdkWindows& WXUNUSED(windows)) const
405{
406    return GTK_RANGE(m_widget)->event_window;
407}
408
409// static
410wxVisualAttributes
411wxSlider::GetClassDefaultAttributes(wxWindowVariant WXUNUSED(variant))
412{
413    return GetDefaultAttributesFromGTKWidget(gtk_vscale_new);
414}
415
416#endif // wxUSE_SLIDER
417