From 9a0f40d4b5d8f5751432a88b1a479add8c814813 Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Wed, 26 Aug 2020 16:34:10 +0200
Subject: [PATCH] LibGUI: Add a top-left-corner button to table views

If both the row and column headers are visible, we now also show a
button in the top left corner. This avoids the headers overlapping
each other when you scroll the contents.

In the future, this could be hooked up to a "select all" action.
---
 Libraries/LibGUI/AbstractTableView.cpp | 14 +++++++++++++-
 Libraries/LibGUI/AbstractTableView.h   |  1 +
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/Libraries/LibGUI/AbstractTableView.cpp b/Libraries/LibGUI/AbstractTableView.cpp
index 4994cca09d2..6f429ba33d7 100644
--- a/Libraries/LibGUI/AbstractTableView.cpp
+++ b/Libraries/LibGUI/AbstractTableView.cpp
@@ -28,6 +28,7 @@
 #include <AK/Vector.h>
 #include <LibGUI/AbstractTableView.h>
 #include <LibGUI/Action.h>
+#include <LibGUI/Button.h>
 #include <LibGUI/HeaderView.h>
 #include <LibGUI/Menu.h>
 #include <LibGUI/Model.h>
@@ -40,6 +41,10 @@ namespace GUI {
 
 AbstractTableView::AbstractTableView()
 {
+    m_corner_button = add<Button>();
+    m_corner_button->move_to_back();
+    m_corner_button->set_background_role(Gfx::ColorRole::ThreedShadow1);
+    m_corner_button->set_fill_with_background_color(true);
     m_column_header = add<HeaderView>(*this, Gfx::Orientation::Horizontal);
     m_column_header->move_to_back();
     m_row_header = add<HeaderView>(*this, Gfx::Orientation::Vertical);
@@ -296,7 +301,7 @@ Gfx::IntRect AbstractTableView::content_rect(const ModelIndex& index) const
 
 Gfx::IntRect AbstractTableView::row_rect(int item_index) const
 {
-    return { row_header().is_visible() ? row_header().width() : 0 , column_header().height() + (item_index * item_height()), max(content_size().width(), width()), item_height() };
+    return { row_header().is_visible() ? row_header().width() : 0, column_header().height() + (item_index * item_height()), max(content_size().width(), width()), item_height() };
 }
 
 Gfx::IntPoint AbstractTableView::adjusted_position(const Gfx::IntPoint& position) const
@@ -360,6 +365,13 @@ void AbstractTableView::layout_headers()
         int y = (frame_thickness() + (column_header().is_visible() ? column_header().height() : 0)) + -vertical_scrollbar().value();
         row_header().set_relative_rect(x, y, row_header().preferred_size().width(), content_height());
     }
+
+    if (row_header().is_visible() && column_header().is_visible()) {
+        m_corner_button->set_relative_rect(frame_thickness(), frame_thickness(), row_header().width(), column_header().height());
+        m_corner_button->set_visible(true);
+    } else {
+        m_corner_button->set_visible(false);
+    }
 }
 
 }
diff --git a/Libraries/LibGUI/AbstractTableView.h b/Libraries/LibGUI/AbstractTableView.h
index 34ca3b4950b..dcc44cc1a29 100644
--- a/Libraries/LibGUI/AbstractTableView.h
+++ b/Libraries/LibGUI/AbstractTableView.h
@@ -112,6 +112,7 @@ private:
 
     RefPtr<HeaderView> m_column_header;
     RefPtr<HeaderView> m_row_header;
+    RefPtr<Button> m_corner_button;
 
     HashMap<int, OwnPtr<TableCellPaintingDelegate>> m_column_painting_delegate;