Decouple scrollbar painting from Scrollbar object
[WebKit-https.git] / Source / WebCore / platform / gtk / ScrollbarThemeGtk2.cpp
1 /*
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25
26 #include "config.h"
27 #include "ScrollbarThemeGtk.h"
28
29 #ifdef GTK_API_VERSION_2
30
31 #include "GtkVersioning.h"
32 #include "PlatformMouseEvent.h"
33 #include "RenderThemeGtk.h"
34 #include "ScrollView.h"
35 #include "Scrollbar.h"
36 #include "WidgetRenderingContext.h"
37 #include <gtk/gtk.h>
38
39 namespace WebCore {
40
41 static void gtkStyleSetCallback(GtkWidget* widget, GtkStyle* previous, ScrollbarThemeGtk* scrollbarTheme)
42 {
43     scrollbarTheme->updateThemeProperties();
44 }
45
46 ScrollbarThemeGtk::ScrollbarThemeGtk()
47 {
48     updateThemeProperties();
49     g_signal_connect(static_cast<RenderThemeGtk*>(RenderTheme::defaultTheme().get())->gtkHScrollbar(),
50          "style-set", G_CALLBACK(gtkStyleSetCallback), this);
51 }
52
53 void ScrollbarThemeGtk::updateThemeProperties()
54 {
55     GtkWidget* scrollbar = static_cast<RenderThemeGtk*>(RenderTheme::defaultTheme().get())->gtkHScrollbar();
56     gtk_widget_style_get(scrollbar,
57                          "slider_width", &m_thumbFatness,
58                          "trough_border", &m_troughBorderWidth,
59                          "stepper-size", &m_stepperSize,
60                          "trough-under-steppers", &m_troughUnderSteppers,
61                          "has-backward-stepper", &m_hasBackButtonStartPart,
62                          "has-forward-stepper", &m_hasForwardButtonEndPart,
63                          "has-secondary-forward-stepper", &m_hasForwardButtonStartPart,
64                          "has-secondary-backward-stepper", &m_hasBackButtonEndPart, NULL);
65     m_minThumbLength = gtk_range_get_min_slider_size(GTK_RANGE(scrollbar));
66     updateScrollbarsFrameThickness();
67 }
68
69 static GtkWidget* getWidgetForScrollbar(ScrollbarThemeClient* scrollbar)
70 {
71     RenderThemeGtk* theme = static_cast<RenderThemeGtk*>(RenderTheme::defaultTheme().get());
72     return scrollbar->orientation() == VerticalScrollbar ? theme->gtkVScrollbar() : theme->gtkHScrollbar();
73 }
74
75 void ScrollbarThemeGtk::paintTrackBackground(GraphicsContext* context, ScrollbarThemeClient* scrollbar, const IntRect& rect)
76 {
77     // Paint the track background. If the trough-under-steppers property is true, this
78     // should be the full size of the scrollbar, but if is false, it should only be the
79     // track rect.
80     IntRect fullScrollbarRect(rect);
81     if (m_troughUnderSteppers)
82         fullScrollbarRect = IntRect(scrollbar->x(), scrollbar->y(), scrollbar->width(), scrollbar->height());
83
84     WidgetRenderingContext widgetContext(context, fullScrollbarRect);
85     IntRect paintRect(IntPoint(), fullScrollbarRect.size());
86     widgetContext.gtkPaintBox(paintRect, getWidgetForScrollbar(scrollbar),
87                               GTK_STATE_ACTIVE, GTK_SHADOW_IN, "trough");
88 }
89
90 void ScrollbarThemeGtk::paintScrollbarBackground(GraphicsContext* context, ScrollbarThemeClient* scrollbar)
91 {
92     IntRect fullScrollbarRect = IntRect(scrollbar->x(), scrollbar->y(), scrollbar->width(), scrollbar->height());
93
94     WidgetRenderingContext widgetContext(context, fullScrollbarRect);
95     widgetContext.gtkPaintBox(fullScrollbarRect, getWidgetForScrollbar(scrollbar),
96                               GTK_STATE_NORMAL, GTK_SHADOW_IN, "scrolled_window");
97 }
98
99 void ScrollbarThemeGtk::paintThumb(GraphicsContext* context, ScrollbarThemeClient* scrollbar, const IntRect& rect)
100 {
101     GtkWidget* widget = getWidgetForScrollbar(scrollbar);
102     gboolean activateSlider;
103     gtk_widget_style_get(widget, "activate-slider", &activateSlider, NULL);
104
105     GtkStateType stateType = GTK_STATE_NORMAL;
106     GtkShadowType shadowType = GTK_SHADOW_OUT;
107     if (activateSlider && scrollbar->pressedPart() == ThumbPart) {
108         stateType = GTK_STATE_ACTIVE;
109         shadowType = GTK_SHADOW_IN;
110     } else if (scrollbar->pressedPart() == ThumbPart || scrollbar->hoveredPart() == ThumbPart)
111         stateType = GTK_STATE_PRELIGHT;
112
113     // The adjustment controls the rendering of the scrollbar thumb. If it's not set
114     // properly the theme may not draw the thumb borders properly.
115     GtkAdjustment* adjustment = gtk_range_get_adjustment(GTK_RANGE(widget));
116     gtk_adjustment_set_value(adjustment, scrollbar->currentPos());
117     gtk_adjustment_set_lower(adjustment, 0);
118     gtk_adjustment_set_upper(adjustment, scrollbar->maximum());
119
120     GtkOrientation orientation = GTK_ORIENTATION_HORIZONTAL;
121     if (scrollbar->orientation() == VerticalScrollbar) {
122         gtk_adjustment_set_page_size(adjustment, rect.height());
123         orientation = GTK_ORIENTATION_VERTICAL;
124     } else
125         gtk_adjustment_set_page_size(adjustment, rect.width());
126
127     WidgetRenderingContext widgetContext(context, rect);
128     IntRect sliderRect(IntPoint(), rect.size());
129     widgetContext.gtkPaintSlider(sliderRect, widget, stateType, shadowType, "slider", orientation);
130 }
131
132 void ScrollbarThemeGtk::paintButton(GraphicsContext* context, ScrollbarThemeClient* scrollbar, const IntRect& rect, ScrollbarPart part)
133 {
134     // The buttons will be disabled if the thumb is as the appropriate extreme.
135     GtkShadowType shadowType = GTK_SHADOW_OUT;
136     GtkStateType stateType = GTK_STATE_INSENSITIVE;
137     bool pressed = (part == scrollbar->pressedPart());
138
139     if ((BackButtonStartPart == part && scrollbar->currentPos())
140         || (BackButtonEndPart == part && scrollbar->currentPos())
141         || (ForwardButtonEndPart == part && scrollbar->currentPos() != scrollbar->maximum())
142         || (ForwardButtonStartPart == part && scrollbar->currentPos() != scrollbar->maximum())) {
143         stateType = GTK_STATE_NORMAL;
144         if (pressed) {
145             stateType = GTK_STATE_ACTIVE;
146             shadowType = GTK_SHADOW_IN;
147         } else if (part == scrollbar->hoveredPart())
148             stateType = GTK_STATE_PRELIGHT;
149     }
150
151     // Themes determine how to draw the button (which button to draw) based on the allocation
152     // of the widget. Where the target rect is in relation to the total widget allocation
153     // determines the button.
154     ScrollbarOrientation orientation = scrollbar->orientation();
155     int buttonSize = (orientation == VerticalScrollbar) ? rect.height() : rect.width();
156     int totalAllocation = buttonSize * 5; // One space for each button and one extra.
157     int buttonOffset = 0;
158     if (ForwardButtonStartPart == part)
159         buttonOffset = buttonSize;
160     else if (BackButtonEndPart == part)
161         buttonOffset = 3 * buttonSize;
162     else if (ForwardButtonEndPart == part)
163         buttonOffset = 4 * buttonSize;
164
165     // Now we want the allocation to be relative to the origin of the painted rect.
166     GtkWidget* widget = getWidgetForScrollbar(scrollbar);
167     GtkAllocation allocation;
168     gtk_widget_get_allocation(widget, &allocation);
169     allocation.x = allocation.y = 0;
170     allocation.width = rect.width();
171     allocation.height = rect.height();
172
173     if (orientation == VerticalScrollbar) {
174         allocation.height = totalAllocation;
175         allocation.y -= buttonOffset;
176     } else {
177         allocation.width = totalAllocation;
178         allocation.x -= buttonOffset;
179     }
180     gtk_widget_set_allocation(widget, &allocation);
181
182     const char* detail = orientation == VerticalScrollbar ? "vscrollbar" : "hscrollbar";
183     WidgetRenderingContext widgetContext(context, rect);
184
185     IntRect buttonRect(IntPoint(), rect.size());
186     widgetContext.gtkPaintBox(buttonRect, widget, stateType, shadowType, detail);
187
188     float arrowScaling;
189     gtk_widget_style_get(widget, "arrow-scaling", &arrowScaling, NULL);
190     IntSize arrowSize = rect.size();
191     arrowSize.scale(arrowScaling);
192     IntRect arrowRect(IntPoint(buttonRect.x() + (buttonRect.width() - arrowSize.width()) / 2,
193                                buttonRect.y() + (buttonRect.height() - arrowSize.height()) / 2),
194                       arrowSize);
195     if (pressed) {
196         int arrowDisplacementX, arrowDisplacementY;
197         gtk_widget_style_get(widget,
198                              "arrow-displacement-x", &arrowDisplacementX,
199                              "arrow-displacement-y", &arrowDisplacementY,
200                              NULL);
201         arrowRect.move(arrowDisplacementX, arrowDisplacementY);
202     }
203
204     GtkArrowType arrowType = GTK_ARROW_DOWN;
205     if (orientation == VerticalScrollbar) {
206         if (part == BackButtonEndPart || part == BackButtonStartPart)
207             arrowType = GTK_ARROW_UP;
208     } else if (orientation == HorizontalScrollbar) {
209         arrowType = GTK_ARROW_RIGHT;
210         if (part == BackButtonEndPart || part == BackButtonStartPart)
211             arrowType = GTK_ARROW_LEFT;
212     }
213     widgetContext.gtkPaintArrow(arrowRect, widget, stateType, shadowType, arrowType, detail);
214 }
215
216 } // namespace WebCore
217
218 #endif // GTK_API_VERSION_2