1 /*
2 * Copyright (C) 2008 Apple Inc. All Rights Reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26 #include "config.h"
27 #include "ScrollbarThemeComposite.h"
28
29 #include "Chrome.h"
30 #include "ChromeClient.h"
31 #include "Frame.h"
32 #include "FrameView.h"
33 #include "GraphicsContext.h"
34 #include "Page.h"
35 #include "PlatformMouseEvent.h"
36 #include "Scrollbar.h"
37 #include "ScrollableArea.h"
38 #include "Settings.h"
39
40 using namespace std;
41
42 namespace WebCore {
43
44 #if PLATFORM(WIN)
pageForScrollView(ScrollView * view)45 static Page* pageForScrollView(ScrollView* view)
46 {
47 if (!view)
48 return 0;
49 if (!view->isFrameView())
50 return 0;
51 FrameView* frameView = static_cast<FrameView*>(view);
52 if (!frameView->frame())
53 return 0;
54 return frameView->frame()->page();
55 }
56 #endif
57
paint(Scrollbar * scrollbar,GraphicsContext * graphicsContext,const IntRect & damageRect)58 bool ScrollbarThemeComposite::paint(Scrollbar* scrollbar, GraphicsContext* graphicsContext, const IntRect& damageRect)
59 {
60 // Create the ScrollbarControlPartMask based on the damageRect
61 ScrollbarControlPartMask scrollMask = NoPart;
62
63 IntRect backButtonStartPaintRect;
64 IntRect backButtonEndPaintRect;
65 IntRect forwardButtonStartPaintRect;
66 IntRect forwardButtonEndPaintRect;
67 if (hasButtons(scrollbar)) {
68 backButtonStartPaintRect = backButtonRect(scrollbar, BackButtonStartPart, true);
69 if (damageRect.intersects(backButtonStartPaintRect))
70 scrollMask |= BackButtonStartPart;
71 backButtonEndPaintRect = backButtonRect(scrollbar, BackButtonEndPart, true);
72 if (damageRect.intersects(backButtonEndPaintRect))
73 scrollMask |= BackButtonEndPart;
74 forwardButtonStartPaintRect = forwardButtonRect(scrollbar, ForwardButtonStartPart, true);
75 if (damageRect.intersects(forwardButtonStartPaintRect))
76 scrollMask |= ForwardButtonStartPart;
77 forwardButtonEndPaintRect = forwardButtonRect(scrollbar, ForwardButtonEndPart, true);
78 if (damageRect.intersects(forwardButtonEndPaintRect))
79 scrollMask |= ForwardButtonEndPart;
80 }
81
82 IntRect startTrackRect;
83 IntRect thumbRect;
84 IntRect endTrackRect;
85 IntRect trackPaintRect = trackRect(scrollbar, true);
86 if (damageRect.intersects(trackPaintRect))
87 scrollMask |= TrackBGPart;
88 bool thumbPresent = hasThumb(scrollbar);
89 if (thumbPresent) {
90 IntRect track = trackRect(scrollbar);
91 splitTrack(scrollbar, track, startTrackRect, thumbRect, endTrackRect);
92 if (damageRect.intersects(thumbRect))
93 scrollMask |= ThumbPart;
94 if (damageRect.intersects(startTrackRect))
95 scrollMask |= BackTrackPart;
96 if (damageRect.intersects(endTrackRect))
97 scrollMask |= ForwardTrackPart;
98 }
99
100 #if PLATFORM(WIN)
101 // FIXME: This API makes the assumption that the custom scrollbar's metrics will match
102 // the theme's metrics. This is not a valid assumption. The ability for a client to paint
103 // custom scrollbars should be removed once scrollbars can be styled via CSS.
104 if (Page* page = pageForScrollView(scrollbar->parent())) {
105 if (page->settings()->shouldPaintCustomScrollbars()) {
106 float proportion = static_cast<float>(scrollbar->visibleSize()) / scrollbar->totalSize();
107 float value = scrollbar->currentPos() / static_cast<float>(scrollbar->maximum());
108 ScrollbarControlState s = 0;
109 if (scrollbar->scrollableArea()->isActive())
110 s |= ActiveScrollbarState;
111 if (scrollbar->enabled())
112 s |= EnabledScrollbarState;
113 if (scrollbar->pressedPart() != NoPart)
114 s |= PressedScrollbarState;
115 if (page->chrome()->client()->paintCustomScrollbar(graphicsContext,
116 scrollbar->frameRect(),
117 scrollbar->controlSize(),
118 s,
119 scrollbar->pressedPart(),
120 scrollbar->orientation() == VerticalScrollbar,
121 value,
122 proportion,
123 scrollMask))
124 return true;
125 }
126 }
127 #endif
128
129 // Paint the scrollbar background (only used by custom CSS scrollbars).
130 paintScrollbarBackground(graphicsContext, scrollbar);
131
132 // Paint the back and forward buttons.
133 if (scrollMask & BackButtonStartPart)
134 paintButton(graphicsContext, scrollbar, backButtonStartPaintRect, BackButtonStartPart);
135 if (scrollMask & BackButtonEndPart)
136 paintButton(graphicsContext, scrollbar, backButtonEndPaintRect, BackButtonEndPart);
137 if (scrollMask & ForwardButtonStartPart)
138 paintButton(graphicsContext, scrollbar, forwardButtonStartPaintRect, ForwardButtonStartPart);
139 if (scrollMask & ForwardButtonEndPart)
140 paintButton(graphicsContext, scrollbar, forwardButtonEndPaintRect, ForwardButtonEndPart);
141
142 if (scrollMask & TrackBGPart)
143 paintTrackBackground(graphicsContext, scrollbar, trackPaintRect);
144
145 if ((scrollMask & ForwardTrackPart) || (scrollMask & BackTrackPart)) {
146 // Paint the track pieces above and below the thumb.
147 if (scrollMask & BackTrackPart)
148 paintTrackPiece(graphicsContext, scrollbar, startTrackRect, BackTrackPart);
149 if (scrollMask & ForwardTrackPart)
150 paintTrackPiece(graphicsContext, scrollbar, endTrackRect, ForwardTrackPart);
151
152 paintTickmarks(graphicsContext, scrollbar, trackPaintRect);
153 }
154
155 // Paint the thumb.
156 if (scrollMask & ThumbPart)
157 paintThumb(graphicsContext, scrollbar, thumbRect);
158
159 return true;
160 }
161
hitTest(Scrollbar * scrollbar,const PlatformMouseEvent & evt)162 ScrollbarPart ScrollbarThemeComposite::hitTest(Scrollbar* scrollbar, const PlatformMouseEvent& evt)
163 {
164 ScrollbarPart result = NoPart;
165 if (!scrollbar->enabled())
166 return result;
167
168 IntPoint mousePosition = scrollbar->convertFromContainingWindow(evt.pos());
169 mousePosition.move(scrollbar->x(), scrollbar->y());
170
171 if (!scrollbar->frameRect().contains(mousePosition))
172 return NoPart;
173
174 result = ScrollbarBGPart;
175
176 IntRect track = trackRect(scrollbar);
177 if (track.contains(mousePosition)) {
178 IntRect beforeThumbRect;
179 IntRect thumbRect;
180 IntRect afterThumbRect;
181 splitTrack(scrollbar, track, beforeThumbRect, thumbRect, afterThumbRect);
182 if (thumbRect.contains(mousePosition))
183 result = ThumbPart;
184 else if (beforeThumbRect.contains(mousePosition))
185 result = BackTrackPart;
186 else if (afterThumbRect.contains(mousePosition))
187 result = ForwardTrackPart;
188 else
189 result = TrackBGPart;
190 } else if (backButtonRect(scrollbar, BackButtonStartPart).contains(mousePosition))
191 result = BackButtonStartPart;
192 else if (backButtonRect(scrollbar, BackButtonEndPart).contains(mousePosition))
193 result = BackButtonEndPart;
194 else if (forwardButtonRect(scrollbar, ForwardButtonStartPart).contains(mousePosition))
195 result = ForwardButtonStartPart;
196 else if (forwardButtonRect(scrollbar, ForwardButtonEndPart).contains(mousePosition))
197 result = ForwardButtonEndPart;
198 return result;
199 }
200
invalidatePart(Scrollbar * scrollbar,ScrollbarPart part)201 void ScrollbarThemeComposite::invalidatePart(Scrollbar* scrollbar, ScrollbarPart part)
202 {
203 if (part == NoPart)
204 return;
205
206 IntRect result;
207 switch (part) {
208 case BackButtonStartPart:
209 result = backButtonRect(scrollbar, BackButtonStartPart, true);
210 break;
211 case BackButtonEndPart:
212 result = backButtonRect(scrollbar, BackButtonEndPart, true);
213 break;
214 case ForwardButtonStartPart:
215 result = forwardButtonRect(scrollbar, ForwardButtonStartPart, true);
216 break;
217 case ForwardButtonEndPart:
218 result = forwardButtonRect(scrollbar, ForwardButtonEndPart, true);
219 break;
220 case TrackBGPart:
221 result = trackRect(scrollbar, true);
222 break;
223 case ScrollbarBGPart:
224 result = scrollbar->frameRect();
225 break;
226 default: {
227 IntRect beforeThumbRect, thumbRect, afterThumbRect;
228 splitTrack(scrollbar, trackRect(scrollbar), beforeThumbRect, thumbRect, afterThumbRect);
229 if (part == BackTrackPart)
230 result = beforeThumbRect;
231 else if (part == ForwardTrackPart)
232 result = afterThumbRect;
233 else
234 result = thumbRect;
235 }
236 }
237 result.move(-scrollbar->x(), -scrollbar->y());
238 scrollbar->invalidateRect(result);
239 }
240
splitTrack(Scrollbar * scrollbar,const IntRect & unconstrainedTrackRect,IntRect & beforeThumbRect,IntRect & thumbRect,IntRect & afterThumbRect)241 void ScrollbarThemeComposite::splitTrack(Scrollbar* scrollbar, const IntRect& unconstrainedTrackRect, IntRect& beforeThumbRect, IntRect& thumbRect, IntRect& afterThumbRect)
242 {
243 // This function won't even get called unless we're big enough to have some combination of these three rects where at least
244 // one of them is non-empty.
245 IntRect trackRect = constrainTrackRectToTrackPieces(scrollbar, unconstrainedTrackRect);
246 int thickness = scrollbar->orientation() == HorizontalScrollbar ? scrollbar->height() : scrollbar->width();
247 int thumbPos = thumbPosition(scrollbar);
248 if (scrollbar->orientation() == HorizontalScrollbar) {
249 thumbRect = IntRect(trackRect.x() + thumbPos, trackRect.y() + (trackRect.height() - thickness) / 2, thumbLength(scrollbar), thickness);
250 beforeThumbRect = IntRect(trackRect.x(), trackRect.y(), thumbPos + thumbRect.width() / 2, trackRect.height());
251 afterThumbRect = IntRect(trackRect.x() + beforeThumbRect.width(), trackRect.y(), trackRect.maxX() - beforeThumbRect.maxX(), trackRect.height());
252 } else {
253 thumbRect = IntRect(trackRect.x() + (trackRect.width() - thickness) / 2, trackRect.y() + thumbPos, thickness, thumbLength(scrollbar));
254 beforeThumbRect = IntRect(trackRect.x(), trackRect.y(), trackRect.width(), thumbPos + thumbRect.height() / 2);
255 afterThumbRect = IntRect(trackRect.x(), trackRect.y() + beforeThumbRect.height(), trackRect.width(), trackRect.maxY() - beforeThumbRect.maxY());
256 }
257 }
258
259 // Returns the size represented by track taking into account scrolling past
260 // the end of the document.
usedTotalSize(Scrollbar * scrollbar)261 static float usedTotalSize(Scrollbar* scrollbar)
262 {
263 float overhangAtStart = -scrollbar->currentPos();
264 float overhangAtEnd = scrollbar->currentPos() + scrollbar->visibleSize() - scrollbar->totalSize();
265 float overhang = max(0.0f, max(overhangAtStart, overhangAtEnd));
266 return scrollbar->totalSize() + overhang;
267 }
268
thumbPosition(Scrollbar * scrollbar)269 int ScrollbarThemeComposite::thumbPosition(Scrollbar* scrollbar)
270 {
271 if (scrollbar->enabled())
272 return max(0.0f, scrollbar->currentPos()) * (trackLength(scrollbar) - thumbLength(scrollbar)) / (usedTotalSize(scrollbar) - scrollbar->visibleSize());
273 return 0;
274 }
275
thumbLength(Scrollbar * scrollbar)276 int ScrollbarThemeComposite::thumbLength(Scrollbar* scrollbar)
277 {
278 if (!scrollbar->enabled())
279 return 0;
280
281 float proportion = scrollbar->visibleSize() / usedTotalSize(scrollbar);
282 int trackLen = trackLength(scrollbar);
283 int length = proportion * trackLen;
284 length = max(length, minimumThumbLength(scrollbar));
285 if (length > trackLen)
286 length = 0; // Once the thumb is below the track length, it just goes away (to make more room for the track).
287 return length;
288 }
289
minimumThumbLength(Scrollbar * scrollbar)290 int ScrollbarThemeComposite::minimumThumbLength(Scrollbar* scrollbar)
291 {
292 return scrollbarThickness(scrollbar->controlSize());
293 }
294
trackPosition(Scrollbar * scrollbar)295 int ScrollbarThemeComposite::trackPosition(Scrollbar* scrollbar)
296 {
297 IntRect constrainedTrackRect = constrainTrackRectToTrackPieces(scrollbar, trackRect(scrollbar));
298 return (scrollbar->orientation() == HorizontalScrollbar) ? constrainedTrackRect.x() - scrollbar->x() : constrainedTrackRect.y() - scrollbar->y();
299 }
300
trackLength(Scrollbar * scrollbar)301 int ScrollbarThemeComposite::trackLength(Scrollbar* scrollbar)
302 {
303 IntRect constrainedTrackRect = constrainTrackRectToTrackPieces(scrollbar, trackRect(scrollbar));
304 return (scrollbar->orientation() == HorizontalScrollbar) ? constrainedTrackRect.width() : constrainedTrackRect.height();
305 }
306
paintScrollCorner(ScrollView * view,GraphicsContext * context,const IntRect & cornerRect)307 void ScrollbarThemeComposite::paintScrollCorner(ScrollView* view, GraphicsContext* context, const IntRect& cornerRect)
308 {
309 FrameView* frameView = static_cast<FrameView*>(view);
310 Page* page = frameView->frame() ? frameView->frame()->page() : 0;
311 if (page && page->settings()->shouldPaintCustomScrollbars() && page->chrome()->client()->paintCustomScrollCorner(context, cornerRect))
312 return;
313 context->fillRect(cornerRect, Color::white, ColorSpaceDeviceRGB);
314 }
315
316 }
317