add Tucan.View.set_view_background/2

CHANGELOG.md

@@ -4,10 +4,11 @@
 
 ### Added
 
-- Support for setting plot's background color through `Tucan.View.set_background/2`
+- Support setting plot's background color through `Tucan.View.set_background/2`
+- Support setting view's background color through `Tucan.View.set_view_background/2`
 - Add `Tucan.Axes.set_offset/3`
-- Support setting axes orientation with `Tucan.Axes.set_orientation/3`
 - Add `Tucan.Legend.set_offset/3`
+- Support setting axes orientation with `Tucan.Axes.set_orientation/3`
 
 ```tucan
 Tucan.scatter(:iris, "petal_width", "petal_length")

lib/tucan/view.ex

@@ -4,7 +4,7 @@ defmodule Tucan.View do
   """
 
   @doc """
-  Sets the background color of the plot view.
+  Sets the background color of the visualization canvas.
 
   ## Examples
 
@@ -17,4 +17,34 @@ defmodule Tucan.View do
   def set_background(vl, color) when is_struct(vl, VegaLite) and is_binary(color) do
     update_in(vl.spec, fn spec -> Map.merge(spec, %{"background" => color}) end)
   end
+
+  @doc """
+  Sets the background color of the view.
+
+  `set_background/2` defines the background of the whole visualization canvas. Meanwhile,
+  the view property of a single-view or layer specification can define the background of
+  the view.
+
+  ## Examples
+
+  Two concatenated plots with different view backgrounds and an overall canvas
+  background.
+
+  ```tucan
+  Tucan.hconcat(
+    Tucan.new(),
+    [
+      Tucan.scatter(:iris, "sepal_width", "sepal_length")
+      |> Tucan.View.set_view_background("#e6fae1"),
+      Tucan.scatter(:iris, "petal_width", "petal_length")
+      |> Tucan.View.set_view_background("#facbc5"),
+    ]
+  )
+  |> Tucan.View.set_background("#fcffde")
+  ```
+  """
+  @spec set_view_background(vl :: VegaLite.t(), color :: String.t()) :: VegaLite.t()
+  def set_view_background(vl, color) do
+    update_in(vl.spec, fn spec -> Map.merge(spec, %{"view" => %{"fill" => color}}) end)
+  end
 end

test/tucan/view_test.exs

@@ -8,4 +8,10 @@ defmodule Tucan.ViewTest do
 
     assert Tucan.View.set_background(Vl.new(), "green") == expected
   end
+
+  test "set_view_background/2" do
+    vl = Tucan.View.set_view_background(Vl.new(), "red")
+
+    assert get_in(vl.spec, ["view"]) == %{"fill" => "red"}
+  end
 end