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#include <LibGUI/GScrollBar.h>
#include <SharedGraphics/GraphicsBitmap.h>
#include <SharedGraphics/Painter.h>
GScrollBar::GScrollBar(GWidget* parent)
: GWidget(parent)
{
}
GScrollBar::~GScrollBar()
{
}
void GScrollBar::set_range(int min, int max)
{
ASSERT(min <= max);
if (m_min == min && m_max == max)
return;
m_min = min;
m_max = max;
int old_value = m_value;
if (m_value < m_min)
m_value = m_min;
if (m_value > m_max)
m_value = m_max;
if (on_change && m_value != old_value)
on_change(m_value);
update();
}
void GScrollBar::set_value(int value)
{
if (value < m_min)
value = m_min;
if (value > m_max)
value = m_max;
if (value == m_value)
return;
m_value = value;
if (on_change)
on_change(value);
update();
}
Rect GScrollBar::up_button_rect() const
{
return { 0, 0, button_size(), button_size() };
}
Rect GScrollBar::down_button_rect() const
{
return { 0, height() - button_size(), button_size(), button_size() };
}
Rect GScrollBar::pgup_rect() const
{
return { 0, button_size(), button_size(), scrubber_rect().top() - button_size() };
}
Rect GScrollBar::pgdn_rect() const
{
auto scrubber_rect = this->scrubber_rect();
return { 0, scrubber_rect.bottom(), button_size(), height() - button_size() - scrubber_rect.bottom() };
}
Rect GScrollBar::scrubber_rect() const
{
int range_size = m_max - m_min;
if (range_size == 0)
return { 0, button_size(), button_size(), height() - button_size() * 2 };
float available_y = height() - button_size() * 3;
float y_step = available_y / range_size;
float y = button_size() + (y_step * m_value);
return { 0, (int)y, button_size(), button_size() };
}
void GScrollBar::paint_event(GPaintEvent&)
{
Painter painter(*this);
painter.fill_rect(rect(), Color::MidGray);
painter.draw_rect(up_button_rect(), Color::DarkGray, true);
painter.fill_rect_with_gradient(up_button_rect().shrunken(2, 2), Color::LightGray, Color::White);
painter.draw_rect(down_button_rect(), Color::DarkGray, true);
painter.fill_rect_with_gradient(down_button_rect().shrunken(2, 2), Color::LightGray, Color::White);
painter.draw_rect(scrubber_rect(), Color::White, true);
painter.fill_rect_with_gradient(scrubber_rect().shrunken(2, 2), Color::LightGray, Color::White);
}
void GScrollBar::mousedown_event(GMouseEvent& event)
{
if (event.button() != GMouseButton::Left)
return;
if (up_button_rect().contains(event.position())) {
set_value(value() - m_step);
return;
}
if (down_button_rect().contains(event.position())) {
set_value(value() + m_step);
return;
}
if (pgup_rect().contains(event.position())) {
set_value(value() - m_big_step);
return;
}
if (pgdn_rect().contains(event.position())) {
set_value(value() + m_big_step);
return;
}
}
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