1 //////////////////////////////////////////////////////////////////////////////
2 //
3 // Copyright (c) 2004-2021 musikcube team
4 //
5 // All rights reserved.
6 //
7 // Redistribution and use in source and binary forms, with or without
8 // modification, are permitted provided that the following conditions are met:
9 //
10 // * Redistributions of source code must retain the above copyright notice,
11 // this list of conditions and the following disclaimer.
12 //
13 // * Redistributions in binary form must reproduce the above copyright
14 // notice, this list of conditions and the following disclaimer in the
15 // documentation and/or other materials provided with the distribution.
16 //
17 // * Neither the name of the author nor the names of other contributors may
18 // be used to endorse or promote products derived from this software
19 // without specific prior written permission.
20 //
21 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
22 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
25 // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26 // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27 // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29 // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31 // POSSIBILITY OF SUCH DAMAGE.
32 //
33 //////////////////////////////////////////////////////////////////////////////
34
35 #include <stdafx.h>
36 #include <algorithm>
37 #include <cursespp/Scrollbar.h>
38
39 using namespace cursespp;
40
Draw(ListWindow * list,Window * target)41 void Scrollbar::Draw(ListWindow* list, Window* target) {
42 if (!list) {
43 return;
44 }
45
46 auto *adapter = &list->GetScrollAdapter();
47 if (adapter) {
48 target = (target == nullptr) ? list : target;
49
50 int trackHeight = target->GetHeight();
51
52 if (target->IsFrameVisible()) {
53 trackHeight -= 2; /* account for border */
54 }
55
56 if (trackHeight > 1) {
57 WINDOW* window = target->GetFrame();
58 if (window) {
59 auto& pos = list->GetScrollPosition();
60 size_t itemCount = adapter->GetEntryCount();
61
62 /* track */
63 int trackX = target->GetWidth() - 1;
64 int trackMinY = target->IsFrameVisible() ? 1 : 0;
65 int trackMaxY = trackMinY + trackHeight;
66
67 /* thumb */
68 int thumbY = -1;
69 if ((int) itemCount > trackHeight) {
70 float percent = (float) pos.logicalIndex / (float) itemCount;
71 thumbY = (int) ((float) trackHeight * percent) + trackMinY;
72 }
73
74 /* validate */
75 assert(trackMinY >= 0);
76 assert(trackMaxY <= target->GetHeight());
77 assert(trackMaxY > trackMinY);
78 assert(trackHeight <= target->GetHeight());
79
80 /* draw */
81 mvwvline(window, trackMinY, trackX, 0, trackHeight); /* track */
82 if (thumbY >= trackMinY && thumbY < trackMaxY) {
83 mvwaddch(window, thumbY, trackX, ' ' | A_REVERSE); /* handle */
84 }
85 }
86 }
87 }
88 }
89