[banshee/grid] [ColumnCellAlbum] First phase of big refactoring

[Aaron Bockover <abock src gnome org>]

commit 866d6a04356c10e83ace0f7f6feabc6eab3dadb9
Author: Aaron Bockover <abockover novell com>
Date:   Thu Dec 17 02:55:26 2009 -0500

    [ColumnCellAlbum] First phase of big refactoring
    
    Most of the big refactoring work is now done for how the soon
    to be new ColumnCellTile will work. The cell renderer now supports
    measure and rendering for list or grid layout (e.g. text to the
    right or below the image) and has some new layout properties.
    
    All of the code specific to rendering AlbumInfo objects has been
    moved into two new virtual methods: RenderImageSurface and
    HandleBoundObject. When ColumnCellAlbum moves to ColumnCellTile,
    these two methods will become abstract, and then ColumnCellAlbum,
    ColumnCellPodcast, and other new renderers can simply derive
    from ColumnCellTile and override the image rendering and implement
    the object binding.
    
    Ok, going to bed now. More tomorrow!

 .../Banshee.Collection.Gui/ColumnCellAlbum.cs      |  178 +++++++++++++-------
 1 files changed, 118 insertions(+), 60 deletions(-)
---
diff --git a/src/Core/Banshee.ThickClient/Banshee.Collection.Gui/ColumnCellAlbum.cs b/src/Core/Banshee.ThickClient/Banshee.Collection.Gui/ColumnCellAlbum.cs
index 98a18bb..2686c68 100644
--- a/src/Core/Banshee.ThickClient/Banshee.Collection.Gui/ColumnCellAlbum.cs
+++ b/src/Core/Banshee.ThickClient/Banshee.Collection.Gui/ColumnCellAlbum.cs
@@ -42,116 +42,114 @@ namespace Banshee.Collection.Gui
 {
     public class ColumnCellAlbum : ColumnCell
     {
-        private static int image_spacing = 4;
-        private static int image_size = 48;
-
         private ArtworkManager artwork_manager;
 
+        public double PaddingX { get; set; }
+        public double PaddingY { get; set; }
+        public double ImageSize { get; set; }
+        public double ImageSpacing { get; set; }
+        public double TextSpacing { get; set; }
+
         public ColumnCellAlbum () : base (null, true)
         {
             artwork_manager = ServiceManager.Get<ArtworkManager> ();
-        }
 
-        private class ColumnCellAlbumAccessible : ColumnCellAccessible
-        {
-            public ColumnCellAlbumAccessible (object bound_object, ColumnCellAlbum cell, ICellAccessibleParent parent)
-                : base (bound_object, cell as ColumnCell, parent)
-            {
-                AlbumInfo bound_album_info = (AlbumInfo)bound_object;
-                Name = String.Format ("{0} - {1}",
-                                     bound_album_info.DisplayTitle,
-                                     bound_album_info.DisplayArtistName);
-            }
-        }
+            PaddingX = PaddingY = 6;
+            ImageSize = 48;
+            ImageSpacing = 4;
+            TextSpacing = 0;
 
-        public override Atk.Object GetAccessible (ICellAccessibleParent parent)
-        {
-            return new ColumnCellAlbumAccessible (BoundObject, this, parent);
+            PaddingX = PaddingY = 5;
+            ImageSize = 90;
+            ImageSpacing = 2;
+            TextSpacing = -2;
         }
 
         public override void Render (CellContext context, StateType state, double cellWidth, double cellHeight)
         {
-            if (BoundObject == null) {
+            double x = 0;
+            double y = 0;
+            double width = ImageSize;
+            double height = ImageSize;
+
+            ImageSurface image_surface;
+            string [] lines;
+
+            if (!HandleBoundObject (out image_surface, out lines)) {
                 return;
             }
 
-            if (!(BoundObject is AlbumInfo)) {
-                throw new InvalidCastException ("ColumnCellAlbum can only bind to AlbumInfo objects");
+            if (PaddingX > 0 || PaddingY > 0) {
+                context.Context.Translate (PaddingX, PaddingY);
             }
 
-            AlbumInfo album = (AlbumInfo)BoundObject;
-
-            int actual_image_size = LayoutStyle == DataViewLayoutStyle.Grid
-                ? (int)Math.Max (Math.Min (cellWidth, cellHeight) - 10, 0)
-                : image_size;
-            ImageSurface image = artwork_manager == null ? null
-                : artwork_manager.LookupScaleSurface (album.ArtworkId, actual_image_size, true);
-
-            // int image_render_size = is_default ? image.Height : (int)cellHeight - 8;
-            int image_render_size = actual_image_size;
-            int x = 0;
-            int y = 0;
+            // Render the image
+            if (image_surface != null) {
+                width = image_surface.Width;
+                height = image_surface.Height;
+            }
 
-            if (LayoutStyle != DataViewLayoutStyle.Grid) {
-                x = image_spacing;
-                y = ((int)cellHeight - image_render_size) / 2;
+            if (LayoutStyle == DataViewLayoutStyle.Grid) {
+                x = Math.Round ((cellWidth - 2 * PaddingX - width) / 2.0);
             } else {
-                x = image_spacing;
-                y = image_spacing;
-                // x = ((int)cellWidth - image_render_size) / 2
+                y = Math.Round ((cellHeight - 2 * PaddingY - height) / 2.0);
             }
 
-            ArtworkRenderer.RenderThumbnail (context.Context, image, false, x, y,
-                image_render_size, image_render_size, true, context.Theme.Context.Radius,
-                image == null, new Color (0.8, 0.8, 0.8));
+            RenderImageSurface (context, new Rectangle (x, y, width, height), image_surface);
+
+            if (lines == null || lines.Length < 2) {
+                return;
+            }
 
+            // Render the text
             int fl_width = 0, fl_height = 0, sl_width = 0, sl_height = 0;
             Cairo.Color text_color = context.Theme.Colors.GetWidgetColor (GtkColorClass.Text, state);
             text_color.A = 0.75;
 
-            Pango.Layout layout = context.Layout;
-            layout.Width = (int)((cellWidth - cellHeight - x - 10) * Pango.Scale.PangoScale);
+            var layout = context.Layout;
             layout.Ellipsize = Pango.EllipsizeMode.End;
             layout.FontDescription.Weight = Pango.Weight.Bold;
 
+            layout.Width = (int)((LayoutStyle == DataViewLayoutStyle.Grid
+                ? cellWidth - 2 * PaddingX
+                : cellWidth - ImageSize - ImageSpacing - 2 * PaddingX) * Pango.Scale.PangoScale);
+
             // Compute the layout sizes for both lines for centering on the cell
             int old_size = layout.FontDescription.Size;
 
-            layout.SetText (album.DisplayTitle);
+            layout.SetText (lines[1]);
             layout.GetPixelSize (out fl_width, out fl_height);
 
-            if (!String.IsNullOrEmpty (album.ArtistName)) {
+            if (!String.IsNullOrEmpty (lines[1])) {
                 layout.FontDescription.Weight = Pango.Weight.Normal;
                 layout.FontDescription.Size = (int)(old_size * Pango.Scale.Small);
                 layout.FontDescription.Style = Pango.Style.Italic;
-                layout.SetText (album.ArtistName);
+                layout.SetText (lines[1]);
                 layout.GetPixelSize (out sl_width, out sl_height);
             }
 
-            // Calculate the layout positioning
-
             if (LayoutStyle == DataViewLayoutStyle.Grid) {
-                x = image_spacing;
-                y = 100 + image_spacing;
+                x = 0;
+                y = ImageSize + ImageSpacing;
             } else {
-                x = ((int)cellHeight - x) + 10;
-                y = (int)((cellHeight - (fl_height + sl_height)) / 2);
+                x = ImageSize + ImageSpacing;
+                y = Math.Round ((cellHeight - fl_height + sl_height) / 2);
             }
 
             // Render the second line first since we have that state already
-            if (!String.IsNullOrEmpty (album.ArtistName)) {
-                context.Context.MoveTo (x, y + fl_height);
+            if (!String.IsNullOrEmpty (lines[0])) {
+                context.Context.MoveTo (x, y + fl_height + TextSpacing);
                 context.Context.Color = text_color;
                 PangoCairoHelper.ShowLayout (context.Context, layout);
             }
 
             // Render the first line, resetting the state
-            layout.SetText (album.DisplayTitle);
+            layout.SetText (lines[0]);
             layout.FontDescription.Weight = Pango.Weight.Bold;
             layout.FontDescription.Size = old_size;
             layout.FontDescription.Style = Pango.Style.Normal;
 
-            layout.SetText (album.DisplayTitle);
+            layout.SetText (lines[0]);
 
             context.Context.MoveTo (x, y);
             text_color.A = 1;
@@ -175,9 +173,69 @@ namespace Banshee.Collection.Gui
                 text_height += layout.FontDescription.MeasureTextHeight (widget.PangoContext);
             }
 
-            return LayoutStyle == DataViewLayoutStyle.Grid
-                ? new Gdk.Size (100, 100 + text_height + 6)
-                : new Gdk.Size (0, (text_height < image_size ? image_size : text_height) + 6);
+            double width, height;
+
+            if (LayoutStyle == DataViewLayoutStyle.Grid) {
+                width = ImageSize + 2 * PaddingX;
+                height = ImageSize + ImageSpacing + TextSpacing + text_height + 2 * PaddingY;
+            } else {
+                double list_text_height = text_height + TextSpacing;
+                width = ImageSize + ImageSpacing + 2 * PaddingY;
+                height = (list_text_height < ImageSize ? ImageSize : list_text_height) + 2 * PaddingX;
+            }
+
+            return new Gdk.Size ((int)Math.Round (width), (int)Math.Round (height));
+        }
+
+        protected virtual void RenderImageSurface (CellContext context, Rectangle allocation, ImageSurface imageSurface)
+        {
+            ArtworkRenderer.RenderThumbnail (context.Context,
+                imageSurface, false,
+                allocation.X, allocation.Y, allocation.Width, allocation.Height,
+                true, context.Theme.Context.Radius,
+                imageSurface == null, new Color (0.8, 0.8, 0.8));
         }
+
+        protected virtual bool HandleBoundObject (out ImageSurface image, out string [] lines)
+        {
+            image = null;
+            lines = null;
+
+            var album = BoundObject as AlbumInfo;
+            if (album == null) {
+                if (BoundObject == null) {
+                    return false;
+                };
+
+                throw new InvalidCastException ("ColumnCellAlbum can only bind to AlbumInfo objects");
+            }
+
+            lines = new [] { album.DisplayTitle, album.DisplayArtistName };
+            image = artwork_manager != null
+                ? artwork_manager.LookupScaleSurface (album.ArtworkId, (int)ImageSize, true)
+                : null;
+
+            return true;
+        }
+
+#region Accessibility
+
+        private class ColumnCellAlbumAccessible : ColumnCellAccessible
+        {
+            public ColumnCellAlbumAccessible (object bound_object, ColumnCellAlbum cell, ICellAccessibleParent parent)
+                : base (bound_object, cell as ColumnCell, parent)
+            {
+                var bound_album_info = (AlbumInfo)bound_object;
+                Name = String.Format ("{0} - {1}", bound_album_info.DisplayTitle, bound_album_info.DisplayArtistName);
+            }
+        }
+
+        public override Atk.Object GetAccessible (ICellAccessibleParent parent)
+        {
+            return new ColumnCellAlbumAccessible (BoundObject, this, parent);
+        }
+
+#endregion
+
     }
 }