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#include <LibGUI/GScrollBar.h>
#include <LibGUI/GScrollableWidget.h>
GScrollableWidget::GScrollableWidget(GWidget* parent)
: GFrame(parent)
{
m_vertical_scrollbar = GScrollBar::construct(Orientation::Vertical, this);
m_vertical_scrollbar->set_step(4);
m_vertical_scrollbar->on_change = [this](int) {
did_scroll();
update();
};
m_horizontal_scrollbar = GScrollBar::construct(Orientation::Horizontal, this);
m_horizontal_scrollbar->set_step(4);
m_horizontal_scrollbar->set_big_step(30);
m_horizontal_scrollbar->on_change = [this](int) {
did_scroll();
update();
};
m_corner_widget = GWidget::construct(this);
m_corner_widget->set_fill_with_background_color(true);
}
GScrollableWidget::~GScrollableWidget()
{
}
void GScrollableWidget::mousewheel_event(GMouseEvent& event)
{
// FIXME: The wheel delta multiplier should probably come from... somewhere?
vertical_scrollbar().set_value(vertical_scrollbar().value() + event.wheel_delta() * 20);
}
void GScrollableWidget::custom_layout()
{
auto inner_rect = frame_inner_rect_for_size(size());
int height_wanted_by_horizontal_scrollbar = m_horizontal_scrollbar->is_visible() ? m_horizontal_scrollbar->preferred_size().height() : 0;
int width_wanted_by_vertical_scrollbar = m_vertical_scrollbar->is_visible() ? m_vertical_scrollbar->preferred_size().width() : 0;
m_vertical_scrollbar->set_relative_rect(
inner_rect.right() + 1 - m_vertical_scrollbar->preferred_size().width(),
inner_rect.top(),
m_vertical_scrollbar->preferred_size().width(),
inner_rect.height() - height_wanted_by_horizontal_scrollbar);
m_horizontal_scrollbar->set_relative_rect(
inner_rect.left(),
inner_rect.bottom() + 1 - m_horizontal_scrollbar->preferred_size().height(),
inner_rect.width() - width_wanted_by_vertical_scrollbar,
m_horizontal_scrollbar->preferred_size().height());
m_corner_widget->set_visible(m_vertical_scrollbar->is_visible() && m_horizontal_scrollbar->is_visible());
if (m_corner_widget->is_visible()) {
Rect corner_rect { m_horizontal_scrollbar->relative_rect().right() + 1, m_vertical_scrollbar->relative_rect().bottom() + 1, width_occupied_by_vertical_scrollbar(), height_occupied_by_horizontal_scrollbar() };
m_corner_widget->set_relative_rect(corner_rect);
}
}
void GScrollableWidget::resize_event(GResizeEvent& event)
{
GFrame::resize_event(event);
update_scrollbar_ranges();
}
Size GScrollableWidget::available_size() const
{
int available_width = frame_inner_rect().width() - m_size_occupied_by_fixed_elements.width() - width_occupied_by_vertical_scrollbar();
int available_height = frame_inner_rect().height() - m_size_occupied_by_fixed_elements.height() - height_occupied_by_horizontal_scrollbar();
return { available_width, available_height };
}
void GScrollableWidget::update_scrollbar_ranges()
{
auto available_size = this->available_size();
int excess_height = max(0, m_content_size.height() - available_size.height());
m_vertical_scrollbar->set_range(0, excess_height);
if (should_hide_unnecessary_scrollbars())
m_vertical_scrollbar->set_visible(excess_height > 0);
int excess_width = max(0, m_content_size.width() - available_size.width());
m_horizontal_scrollbar->set_range(0, excess_width);
if (should_hide_unnecessary_scrollbars())
m_horizontal_scrollbar->set_visible(excess_width > 0);
m_vertical_scrollbar->set_big_step(visible_content_rect().height() - m_vertical_scrollbar->step());
}
void GScrollableWidget::set_content_size(const Size& size)
{
if (m_content_size == size)
return;
m_content_size = size;
update_scrollbar_ranges();
}
void GScrollableWidget::set_size_occupied_by_fixed_elements(const Size& size)
{
if (m_size_occupied_by_fixed_elements == size)
return;
m_size_occupied_by_fixed_elements = size;
update_scrollbar_ranges();
}
int GScrollableWidget::height_occupied_by_horizontal_scrollbar() const
{
return m_horizontal_scrollbar->is_visible() ? m_horizontal_scrollbar->height() : 0;
}
int GScrollableWidget::width_occupied_by_vertical_scrollbar() const
{
return m_vertical_scrollbar->is_visible() ? m_vertical_scrollbar->width() : 0;
}
Rect GScrollableWidget::visible_content_rect() const
{
return {
m_horizontal_scrollbar->value(),
m_vertical_scrollbar->value(),
min(m_content_size.width(), frame_inner_rect().width() - width_occupied_by_vertical_scrollbar() - m_size_occupied_by_fixed_elements.width()),
min(m_content_size.height(), frame_inner_rect().height() - height_occupied_by_horizontal_scrollbar() - m_size_occupied_by_fixed_elements.height())
};
}
void GScrollableWidget::scroll_into_view(const Rect& rect, Orientation orientation)
{
if (orientation == Orientation::Vertical)
return scroll_into_view(rect, false, true);
return scroll_into_view(rect, true, false);
}
void GScrollableWidget::scroll_into_view(const Rect& rect, bool scroll_horizontally, bool scroll_vertically)
{
auto visible_content_rect = this->visible_content_rect();
if (visible_content_rect.contains(rect))
return;
if (scroll_vertically) {
if (rect.top() < visible_content_rect.top())
m_vertical_scrollbar->set_value(rect.top());
else if (rect.bottom() > visible_content_rect.bottom())
m_vertical_scrollbar->set_value(rect.bottom() - visible_content_rect.height());
}
if (scroll_horizontally) {
if (rect.left() < visible_content_rect.left())
m_horizontal_scrollbar->set_value(rect.left());
else if (rect.right() > visible_content_rect.right())
m_horizontal_scrollbar->set_value(rect.right() - visible_content_rect.width());
}
}
void GScrollableWidget::set_scrollbars_enabled(bool scrollbars_enabled)
{
if (m_scrollbars_enabled == scrollbars_enabled)
return;
m_scrollbars_enabled = scrollbars_enabled;
m_vertical_scrollbar->set_visible(m_scrollbars_enabled);
m_horizontal_scrollbar->set_visible(m_scrollbars_enabled);
m_corner_widget->set_visible(m_scrollbars_enabled);
}
void GScrollableWidget::scroll_to_top()
{
scroll_into_view({ 0, 0, 1, 1 }, Orientation::Vertical);
}
void GScrollableWidget::scroll_to_bottom()
{
scroll_into_view({ 0, content_height(), 1, 1 }, Orientation::Vertical);
}
Rect GScrollableWidget::widget_inner_rect() const
{
auto rect = frame_inner_rect();
rect.set_width(rect.width() - width_occupied_by_vertical_scrollbar());
rect.set_height(rect.height() - height_occupied_by_horizontal_scrollbar());
return rect;
}
Point GScrollableWidget::to_content_position(const Point& widget_position) const
{
auto content_position = widget_position;
content_position.move_by(horizontal_scrollbar().value(), vertical_scrollbar().value());
content_position.move_by(-frame_thickness(), -frame_thickness());
return content_position;
}
Point GScrollableWidget::to_widget_position(const Point& content_position) const
{
auto widget_position = content_position;
widget_position.move_by(-horizontal_scrollbar().value(), -vertical_scrollbar().value());
widget_position.move_by(frame_thickness(), frame_thickness());
return widget_position;
}
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