LibGUI: Take ProcessManager's process view and turn it into GTableView.

Make it sufficiently generic that it can be reused for any table data. :^)

LibGUI/GTableView.cpp

@@ -0,0 +1,117 @@
+#include <LibGUI/GTableView.h>
+#include <LibGUI/GTableModel.h>
+#include <LibGUI/GScrollBar.h>
+#include <SharedGraphics/Painter.h>
+
+GTableView::GTableView(GWidget* parent)
+    : GWidget(parent)
+{
+    m_scrollbar = new GScrollBar(Orientation::Vertical, this);
+    m_scrollbar->set_step(4);
+    m_scrollbar->set_big_step(30);
+    m_scrollbar->on_change = [this] (int) {
+        update();
+    };
+}
+
+GTableView::~GTableView()
+{
+}
+
+void GTableView::set_model(OwnPtr<GTableModel>&& model)
+{
+    if (model.ptr() == m_model.ptr())
+        return;
+    if (m_model)
+        m_model->unregister_view(Badge<GTableView>(), *this);
+    m_model = move(model);
+    if (m_model)
+        m_model->register_view(Badge<GTableView>(), *this);
+}
+
+void GTableView::resize_event(GResizeEvent& event)
+{
+    m_scrollbar->set_relative_rect(event.size().width() - m_scrollbar->preferred_size().width(), 0, m_scrollbar->preferred_size().width(), event.size().height());
+}
+
+void GTableView::did_update_model()
+{
+    int excess_height = max(0, (item_count() * item_height()) - height());
+    m_scrollbar->set_range(0, excess_height);
+    update();
+}
+
+Rect GTableView::row_rect(int item_index) const
+{
+    return { 0, header_height() + (item_index * item_height()), width(), item_height() };
+}
+
+void GTableView::mousedown_event(GMouseEvent& event)
+{
+    auto adjusted_position = event.position().translated(0, m_scrollbar->value());
+    if (event.button() == GMouseButton::Left) {
+        for (int i = 0; i < item_count(); ++i) {
+            if (!row_rect(i).contains(adjusted_position))
+                continue;
+            m_model->set_selected_index({ i, 0 });
+            update();
+        }
+    }
+}
+
+void GTableView::paint_event(GPaintEvent&)
+{
+    Painter painter(*this);
+
+    painter.translate(0, -m_scrollbar->value());
+
+    int horizontal_padding = 5;
+    int painted_item_index = 0;
+
+    int y_offset = header_height();
+
+    for (int row_index = 0; row_index < m_model->row_count(); ++row_index) {
+        int y = y_offset + painted_item_index * item_height();
+
+        Color background_color;
+        Color text_color;
+        if (row_index == m_model->selected_index().row()) {
+            background_color = Color::from_rgb(0x84351a);
+            text_color = Color::White;
+        } else {
+            background_color = painted_item_index % 2 ? Color(210, 210, 210) : Color::White;
+            text_color = Color::Black;
+        }
+
+        painter.fill_rect(row_rect(painted_item_index), background_color);
+
+        int x_offset = 0;
+        for (int column_index = 0; column_index < m_model->column_count(); ++column_index) {
+            Rect cell_rect(horizontal_padding + x_offset, y, m_model->column_width(column_index), item_height());
+            painter.draw_text(cell_rect, m_model->data(row_index, column_index), TextAlignment::CenterLeft, text_color);
+            x_offset += m_model->column_width(column_index) + horizontal_padding;
+        }
+        ++painted_item_index;
+    };
+
+    Rect unpainted_rect(0, painted_item_index * item_height(), width(), height());
+    unpainted_rect.intersect(rect());
+    painter.fill_rect(unpainted_rect, Color::White);
+
+    // Untranslate the painter and paint the column headers.
+    painter.translate(0, m_scrollbar->value());
+    painter.fill_rect({ 0, 0, width(), header_height() }, Color::LightGray);
+    int x_offset = 0;
+    for (int column_index = 0; column_index < m_model->column_count(); ++column_index) {
+        Rect cell_rect(horizontal_padding + x_offset, 0, m_model->column_width(column_index), item_height());
+        painter.draw_text(cell_rect, m_model->column_name(column_index), TextAlignment::CenterLeft, Color::Black);
+        x_offset += m_model->column_width(column_index) + horizontal_padding;
+    }
+    painter.draw_line({ 0, 0 }, { width() - 1, 0 }, Color::White);
+    painter.draw_line({ 0, header_height() - 1 }, { width() - 1, header_height() - 1 }, Color::DarkGray);
+}
+
+int GTableView::item_count() const
+{
+    return m_model->row_count();
+}