1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
|
/*
* nheko Copyright (C) 2017 Konstantinos Sideris <siderisk@auth.gr>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "ScrollBar.h"
ScrollBar::ScrollBar(QScrollArea *area, QWidget *parent)
: QScrollBar(parent)
, area_{area}
{}
void
ScrollBar::paintEvent(QPaintEvent *)
{
if (!width() && !height()) {
hide();
return;
}
QPainter p(this);
p.setRenderHint(QPainter::TextAntialiasing);
p.setRenderHint(QPainter::Antialiasing);
p.setRenderHint(QPainter::SmoothPixmapTransform);
p.setPen(Qt::NoPen);
p.setBrush(backgroundColor());
QRect backgroundArea(Padding, 0, handleWidth_, height());
p.drawRoundedRect(backgroundArea, roundRadius_, roundRadius_);
int areaHeight = area_->height();
int widgetHeight = area_->widget()->height();
double visiblePercentage = (double)areaHeight / (double)widgetHeight;
int handleHeight = std::max(visiblePercentage * areaHeight, (double)minHandleHeight_);
if (maximum() == 0) {
return;
}
int handle_y = (value() * (areaHeight - handleHeight - roundRadius_ / 2)) / maximum();
p.setBrush(handleColor());
QRect handleArea(Padding, handle_y, handleWidth_, handleHeight);
p.drawRoundedRect(handleArea, roundRadius_, roundRadius_);
}
|