ladybird/Libraries/LibHTML/HtmlView.cpp
Andreas Kling 884ae80699 LibHTML+Browser: Show target URL of hovered links in Browser statusbar
HtmlView will now invoke the on_link_hover hook when the cursor enters
or leaves a DOM node that has an enclosing link element.

This patch also updates the meaning of Node::enclosing_link_element()
to find the nearest HTMLAnchorElementAncestor *with an href attribute*.
2019-10-19 21:25:49 +02:00

314 lines
9.8 KiB
C++

#include <AK/FileSystemPath.h>
#include <LibCore/CFile.h>
#include <LibDraw/PNGLoader.h>
#include <LibGUI/GApplication.h>
#include <LibGUI/GPainter.h>
#include <LibGUI/GScrollBar.h>
#include <LibGUI/GWindow.h>
#include <LibHTML/DOM/Element.h>
#include <LibHTML/DOM/ElementFactory.h>
#include <LibHTML/DOM/HTMLAnchorElement.h>
#include <LibHTML/DOM/HTMLImageElement.h>
#include <LibHTML/DOM/Text.h>
#include <LibHTML/Dump.h>
#include <LibHTML/Frame.h>
#include <LibHTML/HtmlView.h>
#include <LibHTML/Layout/LayoutDocument.h>
#include <LibHTML/Layout/LayoutNode.h>
#include <LibHTML/Parser/HTMLParser.h>
#include <LibHTML/RenderingContext.h>
#include <LibHTML/ResourceLoader.h>
#include <stdio.h>
HtmlView::HtmlView(GWidget* parent)
: GScrollableWidget(parent)
, m_main_frame(Frame::create())
{
main_frame().on_set_needs_display = [this](auto& content_rect) {
if (content_rect.is_empty()) {
update();
return;
}
Rect adjusted_rect = content_rect;
adjusted_rect.set_location(to_widget_position(content_rect.location()));
update(adjusted_rect);
};
set_frame_shape(FrameShape::Container);
set_frame_shadow(FrameShadow::Sunken);
set_frame_thickness(2);
set_should_hide_unnecessary_scrollbars(true);
set_background_color(Color::White);
}
HtmlView::~HtmlView()
{
}
void HtmlView::set_document(Document* document)
{
if (document == m_document)
return;
if (m_document)
m_document->on_layout_updated = nullptr;
m_document = document;
if (m_document) {
m_document->on_layout_updated = [this] {
layout_and_sync_size();
update();
};
}
main_frame().set_document(document);
#ifdef HTML_DEBUG
if (document != nullptr) {
dbgprintf("\033[33;1mLayout tree before layout:\033[0m\n");
::dump_tree(*layout_root());
}
#endif
layout_and_sync_size();
update();
}
void HtmlView::layout_and_sync_size()
{
if (!document())
return;
bool had_vertical_scrollbar = vertical_scrollbar().is_visible();
bool had_horizontal_scrollbar = horizontal_scrollbar().is_visible();
main_frame().set_size(available_size());
document()->layout();
set_content_size(layout_root()->size());
// NOTE: If layout caused us to gain or lose scrollbars, we have to lay out again
// since the scrollbars now take up some of the available space.
if (had_vertical_scrollbar != vertical_scrollbar().is_visible() || had_horizontal_scrollbar != horizontal_scrollbar().is_visible()) {
main_frame().set_size(available_size());
document()->layout();
set_content_size(layout_root()->size());
}
#ifdef HTML_DEBUG
dbgprintf("\033[33;1mLayout tree after layout:\033[0m\n");
::dump_tree(*layout_root());
#endif
}
void HtmlView::resize_event(GResizeEvent& event)
{
GScrollableWidget::resize_event(event);
layout_and_sync_size();
}
void HtmlView::paint_event(GPaintEvent& event)
{
GFrame::paint_event(event);
GPainter painter(*this);
painter.add_clip_rect(widget_inner_rect());
painter.add_clip_rect(event.rect());
if (!layout_root()) {
painter.fill_rect(event.rect(), background_color());
return;
}
painter.fill_rect(event.rect(), m_document->background_color());
if (auto background_bitmap = m_document->background_image()) {
painter.draw_tiled_bitmap(event.rect(), *background_bitmap);
}
painter.translate(frame_thickness(), frame_thickness());
painter.translate(-horizontal_scrollbar().value(), -vertical_scrollbar().value());
RenderingContext context { painter };
context.set_should_show_line_box_borders(m_should_show_line_box_borders);
context.set_viewport_rect(visible_content_rect());
layout_root()->render(context);
}
void HtmlView::mousemove_event(GMouseEvent& event)
{
if (!layout_root())
return GScrollableWidget::mousemove_event(event);
bool hovered_node_changed = false;
bool is_hovering_link = false;
bool was_hovering_link = m_document->hovered_node() && m_document->hovered_node()->is_link();
auto result = layout_root()->hit_test(to_content_position(event.position()));
const HTMLAnchorElement* hovered_link_element = nullptr;
if (result.layout_node) {
auto* node = result.layout_node->node();
hovered_node_changed = node != m_document->hovered_node();
m_document->set_hovered_node(const_cast<Node*>(node));
if (node) {
hovered_link_element = node->enclosing_link_element();
if (hovered_link_element) {
#ifdef HTML_DEBUG
dbg() << "HtmlView: hovering over a link to " << hovered_link_element->href();
#endif
is_hovering_link = true;
}
}
}
if (window())
window()->set_override_cursor(is_hovering_link ? GStandardCursor::Hand : GStandardCursor::None);
if (hovered_node_changed) {
update();
auto* hovered_html_element = m_document->hovered_node() ? m_document->hovered_node()->enclosing_html_element() : nullptr;
if (hovered_html_element && !hovered_html_element->title().is_null()) {
auto screen_position = screen_relative_rect().location().translated(event.position());
GApplication::the().show_tooltip(hovered_html_element->title(), screen_position.translated(4, 4));
} else {
GApplication::the().hide_tooltip();
}
}
if (is_hovering_link != was_hovering_link) {
if (on_link_hover) {
on_link_hover(hovered_link_element ? m_document->complete_url(hovered_link_element->href()).to_string() : String());
}
}
event.accept();
}
void HtmlView::mousedown_event(GMouseEvent& event)
{
if (!layout_root())
return GScrollableWidget::mousemove_event(event);
bool hovered_node_changed = false;
auto result = layout_root()->hit_test(to_content_position(event.position()));
if (result.layout_node) {
auto* node = result.layout_node->node();
hovered_node_changed = node != m_document->hovered_node();
m_document->set_hovered_node(const_cast<Node*>(node));
if (node) {
if (auto* link = node->enclosing_link_element()) {
dbg() << "HtmlView: clicking on a link to " << link->href();
if (on_link_click)
on_link_click(link->href());
}
}
}
if (hovered_node_changed)
update();
event.accept();
}
void HtmlView::keydown_event(GKeyEvent& event)
{
if (event.modifiers() == 0) {
switch (event.key()) {
case Key_Home:
vertical_scrollbar().set_value(0);
break;
case Key_End:
vertical_scrollbar().set_value(vertical_scrollbar().max());
break;
case Key_Down:
vertical_scrollbar().set_value(vertical_scrollbar().value() + vertical_scrollbar().step());
break;
case Key_Up:
vertical_scrollbar().set_value(vertical_scrollbar().value() - vertical_scrollbar().step());
break;
case Key_Left:
horizontal_scrollbar().set_value(horizontal_scrollbar().value() + horizontal_scrollbar().step());
break;
case Key_Right:
horizontal_scrollbar().set_value(horizontal_scrollbar().value() - horizontal_scrollbar().step());
break;
case Key_PageDown:
vertical_scrollbar().set_value(vertical_scrollbar().value() + frame_inner_rect().height());
break;
case Key_PageUp:
vertical_scrollbar().set_value(vertical_scrollbar().value() - frame_inner_rect().height());
break;
}
}
event.accept();
}
void HtmlView::reload()
{
load(main_frame().document()->url());
}
static RefPtr<Document> create_image_document(const ByteBuffer& data, const URL& url)
{
auto document = adopt(*new Document);
document->set_url(url);
auto bitmap = load_png_from_memory(data.data(), data.size());
ASSERT(bitmap);
auto html_element = create_element(document, "html");
document->append_child(html_element);
auto head_element = create_element(document, "head");
html_element->append_child(head_element);
auto title_element = create_element(document, "title");
head_element->append_child(title_element);
auto basename = FileSystemPath(url.path()).basename();
auto title_text = adopt(*new Text(document, String::format("%s [%dx%d]", basename.characters(), bitmap->width(), bitmap->height())));
title_element->append_child(title_text);
auto body_element = create_element(document, "body");
html_element->append_child(body_element);
auto image_element = create_element(document, "img");
image_element->set_attribute("src", url.to_string());
body_element->append_child(image_element);
return document;
}
void HtmlView::load(const URL& url)
{
dbg() << "HtmlView::load: " << url;
if (window())
window()->set_override_cursor(GStandardCursor::None);
if (on_load_start)
on_load_start(url);
ResourceLoader::the().load(url, [=](auto data) {
if (data.is_null()) {
dbg() << "Load failed!";
ASSERT_NOT_REACHED();
}
RefPtr<Document> document;
if (url.path().ends_with(".png")) {
document = create_image_document(data, url);
} else {
document = parse_html(data, url);
}
ASSERT(document);
set_document(document);
if (on_title_change)
on_title_change(document->title());
});
}
const LayoutDocument* HtmlView::layout_root() const
{
return document() ? document()->layout_node() : nullptr;
}
LayoutDocument* HtmlView::layout_root()
{
if (!document())
return nullptr;
return const_cast<LayoutDocument*>(document()->layout_node());
}