ladybird/LibGUI/GScrollBar.cpp
2019-06-07 11:46:02 +02:00

334 lines
10 KiB
C++

#include <LibGUI/GPainter.h>
#include <LibGUI/GScrollBar.h>
#include <SharedGraphics/CharacterBitmap.h>
#include <SharedGraphics/GraphicsBitmap.h>
#include <SharedGraphics/StylePainter.h>
static const char* s_up_arrow_bitmap_data = {
" "
" # "
" ### "
" ##### "
" ####### "
" ### "
" ### "
" ### "
" "
};
static const char* s_down_arrow_bitmap_data = {
" "
" ### "
" ### "
" ### "
" ####### "
" ##### "
" ### "
" # "
" "
};
static const char* s_left_arrow_bitmap_data = {
" "
" # "
" ## "
" ###### "
" ####### "
" ###### "
" ## "
" # "
" "
};
static const char* s_right_arrow_bitmap_data = {
" "
" # "
" ## "
" ###### "
" ####### "
" ###### "
" ## "
" # "
" "
};
static CharacterBitmap* s_up_arrow_bitmap;
static CharacterBitmap* s_down_arrow_bitmap;
static CharacterBitmap* s_left_arrow_bitmap;
static CharacterBitmap* s_right_arrow_bitmap;
GScrollBar::GScrollBar(Orientation orientation, GWidget* parent)
: GWidget(parent)
, m_orientation(orientation)
{
if (!s_up_arrow_bitmap)
s_up_arrow_bitmap = &CharacterBitmap::create_from_ascii(s_up_arrow_bitmap_data, 9, 9).leak_ref();
if (!s_down_arrow_bitmap)
s_down_arrow_bitmap = &CharacterBitmap::create_from_ascii(s_down_arrow_bitmap_data, 9, 9).leak_ref();
if (!s_left_arrow_bitmap)
s_left_arrow_bitmap = &CharacterBitmap::create_from_ascii(s_left_arrow_bitmap_data, 9, 9).leak_ref();
if (!s_right_arrow_bitmap)
s_right_arrow_bitmap = &CharacterBitmap::create_from_ascii(s_right_arrow_bitmap_data, 9, 9).leak_ref();
if (m_orientation == Orientation::Vertical) {
set_preferred_size({ 15, 0 });
} else {
set_preferred_size({ 0, 15 });
}
m_automatic_scrolling_timer.set_interval(100);
m_automatic_scrolling_timer.on_timeout = [this] {
on_automatic_scrolling_timer_fired();
};
}
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::decrement_button_rect() const
{
return { 0, 0, button_width(), button_height() };
}
Rect GScrollBar::increment_button_rect() const
{
if (orientation() == Orientation::Vertical)
return { 0, height() - button_height(), button_width(), button_height() };
else
return { width() - button_width(), 0, button_width(), button_height() };
}
Rect GScrollBar::decrement_gutter_rect() const
{
if (orientation() == Orientation::Vertical)
return { 0, button_height(), button_width(), scrubber_rect().top() - button_height() };
else
return { button_width(), 0, scrubber_rect().x() - button_width(), button_height() };
}
Rect GScrollBar::increment_gutter_rect() const
{
auto scrubber_rect = this->scrubber_rect();
if (orientation() == Orientation::Vertical)
return { 0, scrubber_rect.bottom() + 1, button_width(), height() - button_height() - scrubber_rect.bottom() - 1 };
else
return { scrubber_rect.right() + 1, 0, width() - button_width() - scrubber_rect.right() - 1, button_width() };
}
int GScrollBar::scrubbable_range_in_pixels() const
{
if (orientation() == Orientation::Vertical)
return height() - button_height() * 2 - scrubber_size();
else
return width() - button_width() * 2 - scrubber_size();
}
bool GScrollBar::has_scrubber() const
{
return m_max != m_min;
}
int GScrollBar::scrubber_size() const
{
int pixel_range = (orientation() == Orientation::Vertical ? height() : width()) - button_size() * 2;
int value_range = m_max - m_min;
return ::max(pixel_range - value_range, button_size());
}
Rect GScrollBar::scrubber_rect() const
{
if (!has_scrubber())
return {};
float x_or_y;
if (m_value == m_min)
x_or_y = button_size();
else if (m_value == m_max)
x_or_y = ((orientation() == Orientation::Vertical ? height() : width()) - button_size() - scrubber_size()) + 1;
else {
float range_size = m_max - m_min;
float available = scrubbable_range_in_pixels();
float step = available / range_size;
x_or_y = (button_size() + (step * m_value));
}
if (orientation() == Orientation::Vertical)
return { 0, (int)x_or_y, button_width(), scrubber_size() };
else
return { (int)x_or_y, 0, scrubber_size(), button_height() };
}
void GScrollBar::paint_event(GPaintEvent& event)
{
GPainter painter(*this);
painter.add_clip_rect(event.rect());
painter.fill_rect(rect(), Color::from_rgb(0xd6d2ce));
StylePainter::paint_button(painter, decrement_button_rect(), ButtonStyle::Normal, false, m_hovered_component == Component::DecrementButton);
painter.draw_bitmap(decrement_button_rect().location().translated(3, 3), orientation() == Orientation::Vertical ? *s_up_arrow_bitmap : *s_left_arrow_bitmap, has_scrubber() ? Color::Black : Color::MidGray);
StylePainter::paint_button(painter, increment_button_rect(), ButtonStyle::Normal, false, m_hovered_component == Component::IncrementButton);
painter.draw_bitmap(increment_button_rect().location().translated(3, 3), orientation() == Orientation::Vertical ? *s_down_arrow_bitmap : *s_right_arrow_bitmap, has_scrubber() ? Color::Black : Color::MidGray);
if (has_scrubber())
StylePainter::paint_button(painter, scrubber_rect(), ButtonStyle::Normal, false, m_hovered_component == Component::Scrubber);
}
void GScrollBar::on_automatic_scrolling_timer_fired()
{
if (m_automatic_scrolling_direction == AutomaticScrollingDirection::Decrement) {
set_value(value() - m_step);
return;
}
if (m_automatic_scrolling_direction == AutomaticScrollingDirection::Increment) {
set_value(value() + m_step);
return;
}
}
void GScrollBar::mousedown_event(GMouseEvent& event)
{
if (event.button() != GMouseButton::Left)
return;
if (decrement_button_rect().contains(event.position())) {
m_automatic_scrolling_direction = AutomaticScrollingDirection::Decrement;
set_automatic_scrolling_active(true);
return;
}
if (increment_button_rect().contains(event.position())) {
m_automatic_scrolling_direction = AutomaticScrollingDirection::Increment;
set_automatic_scrolling_active(true);
return;
}
if (has_scrubber() && scrubber_rect().contains(event.position())) {
m_scrubbing = true;
m_scrub_start_value = value();
m_scrub_origin = event.position();
update();
return;
}
if (has_scrubber()) {
float range_size = m_max - m_min;
float available = scrubbable_range_in_pixels();
float x = ::max(0, event.position().x() - button_width() - button_width() / 2);
float y = ::max(0, event.position().y() - button_height() - button_height() / 2);
float rel_x = x / available;
float rel_y = y / available;
if (orientation() == Orientation::Vertical)
set_value(m_min + rel_y * range_size);
else
set_value(m_min + rel_x * range_size);
m_scrubbing = true;
m_scrub_start_value = value();
m_scrub_origin = event.position();
}
}
void GScrollBar::mouseup_event(GMouseEvent& event)
{
if (event.button() != GMouseButton::Left)
return;
m_automatic_scrolling_direction = AutomaticScrollingDirection::None;
set_automatic_scrolling_active(false);
if (!m_scrubbing)
return;
m_scrubbing = false;
update();
}
void GScrollBar::set_automatic_scrolling_active(bool active)
{
if (active) {
on_automatic_scrolling_timer_fired();
m_automatic_scrolling_timer.start();
} else {
m_automatic_scrolling_timer.stop();
}
}
void GScrollBar::mousemove_event(GMouseEvent& event)
{
auto old_hovered_component = m_hovered_component;
if (scrubber_rect().contains(event.position()))
m_hovered_component = Component::Scrubber;
else if (decrement_button_rect().contains(event.position()))
m_hovered_component = Component::DecrementButton;
else if (increment_button_rect().contains(event.position()))
m_hovered_component = Component::IncrementButton;
else if (rect().contains(event.position()))
m_hovered_component = Component::Gutter;
else
m_hovered_component = Component::Invalid;
if (old_hovered_component != m_hovered_component) {
update();
if (m_automatic_scrolling_direction == AutomaticScrollingDirection::Decrement)
set_automatic_scrolling_active(m_hovered_component == Component::DecrementButton);
else if (m_automatic_scrolling_direction == AutomaticScrollingDirection::Increment)
set_automatic_scrolling_active(m_hovered_component == Component::IncrementButton);
}
if (!m_scrubbing)
return;
float delta = orientation() == Orientation::Vertical ? (event.y() - m_scrub_origin.y()) : (event.x() - m_scrub_origin.x());
float scrubbable_range = scrubbable_range_in_pixels();
float value_steps_per_scrubbed_pixel = (m_max - m_min) / scrubbable_range;
float new_value = m_scrub_start_value + (value_steps_per_scrubbed_pixel * delta);
set_value(new_value);
}
void GScrollBar::leave_event(CEvent&)
{
if (m_hovered_component != Component::Invalid) {
m_hovered_component = Component::Invalid;
update();
}
}
void GScrollBar::change_event(GEvent& event)
{
if (event.type() == GEvent::Type::EnabledChange) {
if (!is_enabled())
m_scrubbing = false;
}
return GWidget::change_event(event);
}