From 64b1e9deec886cd4d66da144eda24833e6fcf23d Mon Sep 17 00:00:00 2001
From: Andreas Kling <awesomekling@gmail.com>
Date: Sat, 7 Sep 2019 21:45:06 +0200
Subject: [PATCH] GTreeView: Make double-clicking toggle openable items

---
 Libraries/LibGUI/GTreeView.cpp | 18 ++++++++++++++++++
 Libraries/LibGUI/GTreeView.h   |  1 +
 2 files changed, 19 insertions(+)

diff --git a/Libraries/LibGUI/GTreeView.cpp b/Libraries/LibGUI/GTreeView.cpp
index d20ae6d4ea..33b665e768 100644
--- a/Libraries/LibGUI/GTreeView.cpp
+++ b/Libraries/LibGUI/GTreeView.cpp
@@ -77,6 +77,24 @@ void GTreeView::mousedown_event(GMouseEvent& event)
         toggle_index(index);
 }
 
+void GTreeView::doubleclick_event(GMouseEvent& event)
+{
+    if (!model())
+        return;
+    auto& model = *this->model();
+    auto adjusted_position = event.position().translated(horizontal_scrollbar().value() - frame_thickness(), vertical_scrollbar().value() - frame_thickness());
+    bool is_toggle;
+    auto index = index_at_content_position(adjusted_position, is_toggle);
+    if (!index.is_valid())
+        return;
+
+    if (selection().first() != index)
+        selection().set(index);
+
+    if (model.row_count(index))
+        toggle_index(index);
+}
+
 void GTreeView::toggle_index(const GModelIndex& index)
 {
     ASSERT(model()->row_count(index));
diff --git a/Libraries/LibGUI/GTreeView.h b/Libraries/LibGUI/GTreeView.h
index a4a7ec0d3f..d08b9931e3 100644
--- a/Libraries/LibGUI/GTreeView.h
+++ b/Libraries/LibGUI/GTreeView.h
@@ -13,6 +13,7 @@ public:
 protected:
     virtual void paint_event(GPaintEvent&) override;
     virtual void mousedown_event(GMouseEvent&) override;
+    virtual void doubleclick_event(GMouseEvent&) override;
     virtual void keydown_event(GKeyEvent&) override;
     virtual void did_update_selection() override;
     virtual void did_update_model() override;