From fbeaf76f9699fcb52b6a4b1fb1494a69601c13ed Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Wed, 13 May 2020 00:21:13 +0200
Subject: [PATCH] PaintBrush: Update the LayerModel when moving layers around

This ensures that the layer table view always shows the correct
coordinates for the layer.
---
 Applications/PaintBrush/ImageEditor.cpp | 6 ++++++
 Applications/PaintBrush/ImageEditor.h   | 2 ++
 Applications/PaintBrush/LayerModel.h    | 2 ++
 Applications/PaintBrush/MoveTool.cpp    | 2 +-
 4 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/Applications/PaintBrush/ImageEditor.cpp b/Applications/PaintBrush/ImageEditor.cpp
index 95018fdfe6..51c735c57a 100644
--- a/Applications/PaintBrush/ImageEditor.cpp
+++ b/Applications/PaintBrush/ImageEditor.cpp
@@ -120,4 +120,10 @@ void ImageEditor::set_active_tool(Tool* tool)
         m_active_tool->setup(*this);
 }
 
+void ImageEditor::layers_did_change()
+{
+    static_cast<LayerModel&>(m_image->layer_model()).update_without_invalidating_indexes();
+    update();
+}
+
 }
diff --git a/Applications/PaintBrush/ImageEditor.h b/Applications/PaintBrush/ImageEditor.h
index c57599ee07..e1b273ae8c 100644
--- a/Applications/PaintBrush/ImageEditor.h
+++ b/Applications/PaintBrush/ImageEditor.h
@@ -49,6 +49,8 @@ public:
     Tool* active_tool() { return m_active_tool; }
     void set_active_tool(Tool*);
 
+    void layers_did_change();
+
 private:
     ImageEditor();
 
diff --git a/Applications/PaintBrush/LayerModel.h b/Applications/PaintBrush/LayerModel.h
index a6d9884c1e..e4a8bc1229 100644
--- a/Applications/PaintBrush/LayerModel.h
+++ b/Applications/PaintBrush/LayerModel.h
@@ -49,6 +49,8 @@ public:
     virtual GUI::Variant data(const GUI::ModelIndex&, Role = Role::Display) const override;
     virtual void update() override { did_update(); }
 
+    void update_without_invalidating_indexes() { did_update(0); }
+
 private:
     explicit LayerModel(Image&);
 
diff --git a/Applications/PaintBrush/MoveTool.cpp b/Applications/PaintBrush/MoveTool.cpp
index 6673adda44..e497ee926a 100644
--- a/Applications/PaintBrush/MoveTool.cpp
+++ b/Applications/PaintBrush/MoveTool.cpp
@@ -59,7 +59,7 @@ void MoveTool::on_mousemove(Layer&, GUI::MouseEvent&, GUI::MouseEvent& original_
         return;
     auto delta = original_event.position() - m_event_origin;
     m_layer_being_moved->set_location(m_layer_origin.translated(delta));
-    m_editor->update();
+    m_editor->layers_did_change();
 }
 
 void MoveTool::on_mouseup(Layer&, GUI::MouseEvent& event, GUI::MouseEvent&)