change palette

Author: melonora

src/spatialdata_plot/pl/render.py

@@ -83,6 +83,7 @@ def _render_shapes(
         color_source_vector, color_vector, _ = _set_color_source_vec(
             sdata=sdata_filt,
             element=sdata_filt.shapes[e],
+            element_index=index,
             element_name=e,
             value_to_plot=render_params.col_for_color[index],
             groups=render_params.groups[index] if render_params.groups[index][0] is not None else None,
@@ -248,6 +249,7 @@ def _render_points(
         color_source_vector, color_vector, _ = _set_color_source_vec(
             sdata=sdata_filt,
             element=points,
+            element_index=index,
             element_name=e,
             value_to_plot=render_params.col_for_color[index],
             groups=render_params.groups[index] if render_params.groups[index][0] is not None else None,
@@ -591,6 +593,7 @@ def _render_labels(
         color_source_vector, color_vector, categorical = _set_color_source_vec(
             sdata=sdata_filt,
             element=label,
+            element_index=i,
             element_name=e,
             value_to_plot=render_params.color[i],
             groups=render_params.groups,

src/spatialdata_plot/pl/utils.py

@@ -592,6 +592,7 @@ def _get_colors_for_categorical_obs(
 def _set_color_source_vec(
     sdata: sd.SpatialData,
     element: SpatialElement | None,
+    element_index: int,
     value_to_plot: str | None,
     element_name: list[str] | str | None = None,
     groups: Sequence[str] | str | None = None,
@@ -617,7 +618,7 @@ def _set_color_source_vec(
 
         # numerical case, return early
         if color_source_vector is not None and not isinstance(color_source_vector.dtype, pd.CategoricalDtype):
-            if palette is not None:
+            if palette[element_index][0] is not None:
                 logger.warning(
                     "Ignoring categorical palette which is given for a continuous variable. "
                     "Consider using `cmap` to pass a ColorMap."
@@ -1830,5 +1831,8 @@ def _update_params(sdata, params, wanted_elements_on_cs, element_type: Literal["
             params = _update_element_table_mapping_label_colors(sdata, params, wanted_elements_on_cs)
         else:
             params = _validate_colors_element_table_mapping_points_shapes(sdata, params, wanted_elements_on_cs)
+
+    if params.palette is None:
+        params.palette = [[None] for _ in wanted_elements_on_cs]
     image_flag = element_type == "images"
     return _match_length_elements_groups_palette(params, wanted_elements_on_cs, image=image_flag)

tests/pl/test_render_labels.py

@@ -83,3 +83,13 @@ def test_plot_can_color_labels(self, sdata_blobs: SpatialData):
         sdata_blobs.pl.render_labels(
             color=["channel_0_sum", "channel_1_sum"], table_name=["table", "multi_table"]
         ).pl.show()
+
+    def test_can_plot_with_one_element_color_table(self, sdata_blobs: SpatialData):
+        table = sdata_blobs["table"].copy()
+        table.obs["region"] = "blobs_multiscale_labels"
+        table.uns["spatialdata_attrs"]["region"] = "blobs_multiscale_labels"
+        table = table[:, ~table.var_names.isin(["channel_0_sum"])]
+        sdata_blobs["multi_table"] = table
+        sdata_blobs.pl.render_labels(
+            color=["channel_0_sum"], table_name=["table"]
+        ).pl.show()