LibGUI: Make scrollbar thumb size relative to content size

In order to calculate a thumb size that is a representation
of the visible portion (page) of the content, that information
needs to be taken into account.
This commit is contained in:
Tom 2020-07-08 22:12:24 -06:00 committed by Andreas Kling
parent 6df87b51f7
commit fc568ea13a
Notes: sideshowbarker 2024-07-19 05:00:26 +09:00
3 changed files with 22 additions and 8 deletions

View File

@ -115,14 +115,17 @@ ScrollBar::~ScrollBar()
{
}
void ScrollBar::set_range(int min, int max)
void ScrollBar::set_range(int min, int max, int page)
{
ASSERT(min <= max);
if (m_min == min && m_max == max)
if (page < 0)
page = 0;
if (m_min == min && m_max == max && m_page == page)
return;
m_min = min;
m_max = max;
m_page = page;
int old_value = m_value;
m_value = clamp(m_value, m_min, m_max);
@ -190,7 +193,14 @@ int ScrollBar::scrubber_size() const
{
int pixel_range = length(orientation()) - button_size() * 2;
int value_range = m_max - m_min;
return ::max(pixel_range - value_range, button_size());
int scrubber_size = 0;
if (value_range > 0) {
// Scrubber size should be proportional to the visible portion
// (page) in relation to the content (value range + page)
scrubber_size = (m_page * pixel_range) / (value_range + m_page);
}
return ::max(scrubber_size, button_size());
}
Gfx::IntRect ScrollBar::scrubber_rect() const

View File

@ -43,12 +43,15 @@ public:
int value() const { return m_value; }
int min() const { return m_min; }
int max() const { return m_max; }
int page() const { return m_page; }
int step() const { return m_step; }
int big_step() const { return m_big_step; }
void set_min(int min) { set_range(min, max()); }
void set_max(int max) { set_range(min(), max); }
void set_range(int min, int max);
void set_min(int min) { set_range(min, max(), page()); }
void set_max(int max) { set_range(min(), max, page()); }
void set_page(int page) { set_range(min(), max(), page); }
void set_range(int min, int max) { set_range(min, max, page()); }
void set_range(int min, int max, int page);
void set_value(int value);
void set_step(int step) { m_step = step; }
void set_big_step(int big_step) { m_big_step = big_step; }
@ -91,6 +94,7 @@ private:
int m_min { 0 };
int m_max { 0 };
int m_page { 0 };
int m_value { 0 };
int m_step { 1 };
int m_big_step { 5 };

View File

@ -107,13 +107,13 @@ void ScrollableWidget::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);
m_vertical_scrollbar->set_range(0, excess_height, available_size.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);
m_horizontal_scrollbar->set_range(0, excess_width, available_size.width());
if (should_hide_unnecessary_scrollbars())
m_horizontal_scrollbar->set_visible(excess_width > 0);