Add popup position and anchor

examples/user_guide/13-Custom_Interactivity.ipynb

@@ -483,6 +483,55 @@
     ")"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "The `popup_position` can be set to one of the following options:\n",
+    "\n",
+    "- `top_right` (the default)\n",
+    "- `top_left`\n",
+    "- `bottom_left`\n",
+    "- `bottom_right`\n",
+    "- `right`\n",
+    "- `left`\n",
+    "- `top`\n",
+    "- `bottom`\n",
+    "\n",
+    "The `popup_anchor` is automatically determined based on the `popup_position`, but can also be manually set to one of the following predefined positions:\n",
+    "\n",
+    "- `top_left`, `top_center`, `top_right`\n",
+    "- `center_left`, `center_center`, `center_right`\n",
+    "- `bottom_left`, `bottom_center`, `bottom_right`\n",
+    "- `top`, `left`, `center`, `right`, `bottom`\n",
+    "\n",
+    "Alternatively, the `popup_anchor` can be specified as a tuple, using a mix of `start`, `center`, `end`, like `(\"start\", \"center\")`."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "hv.streams.Selection1D(\n",
+    "    source=points,\n",
+    "    popup=popup_stats,\n",
+    "    popup_position=\"left\",\n",
+    "    popup_anchor=\"right\"\n",
+    ")\n",
+    "\n",
+    "points.opts(\n",
+    "    tools=[\"box_select\", \"lasso_select\", \"tap\"],\n",
+    "    active_tools=[\"lasso_select\"],\n",
+    "    size=6,\n",
+    "    color=\"black\",\n",
+    "    fill_color=None,\n",
+    "    width=500,\n",
+    "    height=500\n",
+    ")"
+   ]
+  },
   {
    "cell_type": "markdown",
    "metadata": {},

holoviews/plotting/bokeh/callbacks.py

@@ -75,6 +75,17 @@
 from ...util.warnings import warn
 from .util import BOKEH_GE_3_3_0, convert_timestamp
 
+POPUP_POSITION_ANCHOR = {
+    "top_right": "top_left",
+    "top_left": "top_right",
+    "bottom_left": "bottom_right",
+    "bottom_right": "bottom_left",
+    "right": "top_left",
+    "left": "top_right",
+    "top": "bottom",
+    "bottom": "top",
+}
+
 
 class Callback:
     """
@@ -611,9 +622,10 @@ def initialize(self, plot_id=None):
         }
         """],
         css_classes=["popup-close-btn"])
+        self._popup_position = stream.popup_position
         self._panel = Panel(
             position=XY(x=np.nan, y=np.nan),
-            anchor="top_left",
+            anchor=stream.popup_anchor or POPUP_POSITION_ANCHOR.get(self._popup_position, 'top_left'),
             elements=[close_button],
             visible=False,
             styles={"zIndex": "1000"},
@@ -627,24 +639,56 @@ def _watch_position(self):
         geom_type = self.geom_type
         self.plot.state.on_event('selectiongeometry', self._update_selection_event)
         self.plot.state.js_on_event('selectiongeometry', CustomJS(
-            args=dict(panel=self._panel),
+            args=dict(panel=self._panel, popup_position=self._popup_position),
             code=f"""
-            export default ({{panel}}, cb_obj, _) => {{
-              const el = panel.elements[1]
-              if ((el && !el.visible) || !cb_obj.final || ({geom_type!r} !== 'any' && cb_obj.geometry.type !== {geom_type!r})) {{
-                 return
-              }}
-              let pos;
-              if (cb_obj.geometry.type === 'point') {{
-                pos = {{x: cb_obj.geometry.x, y: cb_obj.geometry.y}}
-              }} else if (cb_obj.geometry.type === 'rect') {{
-                pos = {{x: cb_obj.geometry.x1, y: cb_obj.geometry.y1}}
-              }} else if (cb_obj.geometry.type === 'poly') {{
-                pos = {{x: Math.max(...cb_obj.geometry.x), y: Math.max(...cb_obj.geometry.y)}}
-              }}
-              if (pos) {{
-                panel.position.setv(pos)
-              }}
+            export default ({{panel, popup_position}}, cb_obj, _) => {{
+                const el = panel.elements[1];
+                if ((el && !el.visible) || !cb_obj.final || ({geom_type!r} !== 'any' && cb_obj.geometry.type !== {geom_type!r})) {{
+                    return;
+                }}
+
+                let pos;
+                if (cb_obj.geometry.type === 'point') {{
+                    pos = {{x: cb_obj.geometry.x, y: cb_obj.geometry.y}};
+                }} else if (cb_obj.geometry.type === 'rect') {{
+                    let x, y;
+                    if (popup_position.includes('left')) {{
+                        x = cb_obj.geometry.x0;
+                    }} else if (popup_position.includes('right')) {{
+                        x = cb_obj.geometry.x1;
+                    }} else {{
+                        x = (cb_obj.geometry.x0 + cb_obj.geometry.x1) / 2;
+                    }}
+                    if (popup_position.includes('top')) {{
+                        y = cb_obj.geometry.y1;
+                    }} else if (popup_position.includes('bottom')) {{
+                        y = cb_obj.geometry.y0;
+                    }} else {{
+                        y = (cb_obj.geometry.y0 + cb_obj.geometry.y1) / 2;
+                    }}
+                    pos = {{x: x, y: y}};
+                }} else if (cb_obj.geometry.type === 'poly') {{
+                    let x, y;
+                    if (popup_position.includes('left')) {{
+                        x = Math.min(...cb_obj.geometry.x);
+                    }} else if (popup_position.includes('right')) {{
+                        x = Math.max(...cb_obj.geometry.x);
+                    }} else {{
+                        x = (Math.min(...cb_obj.geometry.x) + Math.max(...cb_obj.geometry.x)) / 2;
+                    }}
+                    if (popup_position.includes('top')) {{
+                        y = Math.max(...cb_obj.geometry.y);
+                    }} else if (popup_position.includes('bottom')) {{
+                        y = Math.min(...cb_obj.geometry.y);
+                    }} else {{
+                        y = (Math.min(...cb_obj.geometry.y) + Math.max(...cb_obj.geometry.y)) / 2;
+                    }}
+                    pos = {{x: x, y: y}};
+                }}
+
+                if (pos) {{
+                    panel.position.setv(pos);
+                }}
             }}""",
         ))
 
@@ -1173,61 +1217,71 @@ def _watch_position(self):
         source = self.plot.handles['source']
         renderer = self.plot.handles['glyph_renderer']
         selected = self.plot.handles['selected']
+
         self.plot.state.js_on_event('selectiongeometry', CustomJS(
-            args=dict(panel=self._panel, renderer=renderer, source=source, selected=selected),
+            args=dict(panel=self._panel, renderer=renderer, source=source, selected=selected, popup_position=self._popup_position),
             code="""
-            export default ({panel, renderer, source, selected}, cb_obj, _) => {
-              const el = panel.elements[1]
-              if ((el && !el.visible) || !cb_obj.final) {
-                 return
-              }
-              let x, y, xs, ys;
-              let indices = selected.indices;
-              if (cb_obj.geometry.type == 'point') {
-                indices = indices.slice(-1)
-              }
-              if (renderer.glyph.x && renderer.glyph.y) {
-                xs = source.get_column(renderer.glyph.x.field)
-                ys = source.get_column(renderer.glyph.y.field)
-              } else if (renderer.glyph.right && renderer.glyph.top) {
-                xs = source.get_column(renderer.glyph.right.field)
-                ys = source.get_column(renderer.glyph.top.field)
-              } else if (renderer.glyph.x1 && renderer.glyph.y1) {
-                xs = source.get_column(renderer.glyph.x1.field)
-                ys = source.get_column(renderer.glyph.y1.field)
-              } else if (renderer.glyph.xs && renderer.glyph.ys) {
-                xs = source.get_column(renderer.glyph.xs.field)
-                ys = source.get_column(renderer.glyph.ys.field)
-              }
-              if (!xs || !ys) { return }
-              for (const i of indices) {
-                let ix = xs[i]
-                let iy = ys[i]
-                let tx, ty
-                if (typeof ix === 'number') {
-                  tx = ix
-                  ty = iy
-                } else {
-                  while (ix.length && (typeof ix[0] !== 'number')) {
-                    ix = ix[0]
-                    iy = iy[0]
-                  }
-                  tx = Math.max(...ix)
-                  ty = Math.max(...iy)
+            export default ({panel, renderer, source, selected, popup_position}, cb_obj, _) => {
+                const el = panel.elements[1];
+                if ((el && !el.visible) || !cb_obj.final) {
+                    return;
                 }
-                if (!x || (tx > x)) {
-                  x = tx
+                let x, y, xs, ys;
+                let indices = selected.indices;
+                if (cb_obj.geometry.type == 'point') {
+                    indices = indices.slice(-1);
                 }
-                if (!y || (ty > y)) {
-                  y = ty
+                if (renderer.glyph.x && renderer.glyph.y) {
+                    xs = source.get_column(renderer.glyph.x.field);
+                    ys = source.get_column(renderer.glyph.y.field);
+                } else if (renderer.glyph.right && renderer.glyph.top) {
+                    xs = source.get_column(renderer.glyph.right.field);
+                    ys = source.get_column(renderer.glyph.top.field);
+                } else if (renderer.glyph.x1 && renderer.glyph.y1) {
+                    xs = source.get_column(renderer.glyph.x1.field);
+                    ys = source.get_column(renderer.glyph.y1.field);
+                } else if (renderer.glyph.xs && renderer.glyph.ys) {
+                    xs = source.get_column(renderer.glyph.xs.field);
+                    ys = source.get_column(renderer.glyph.ys.field);
                 }
-              }
-              if (x && y) {
-                panel.position.setv({x, y})
-              }
-            }""",
+                if (!xs || !ys) { return; }
+
+                let minX = null, maxX = null, minY = null, maxY = null;
+
+                for (const i of indices) {
+                    const tx = xs[i];
+                    const ty = ys[i];
+
+                    if (minX === null || tx < minX) { minX = tx; }
+                    if (maxX === null || tx > maxX) { maxX = tx; }
+                    if (minY === null || ty < minY) { minY = ty; }
+                    if (maxY === null || ty > maxY) { maxY = ty; }
+                }
+
+                if (minX !== null && maxX !== null && minY !== null && maxY !== null) {
+                    if (popup_position.includes('left')) {
+                        x = minX;
+                    } else if (popup_position.includes('right')) {
+                        x = maxX;
+                    } else {
+                        x = (minX + maxX) / 2;
+                    }
+
+                    if (popup_position.includes('top')) {
+                        y = maxY;
+                    } else if (popup_position.includes('bottom')) {
+                        y = minY;
+                    } else {
+                        y = (minY + maxY) / 2;
+                    }
+
+                    panel.position.setv({x, y});
+                }
+            }
+            """,
         ))
 
+
     def _get_position(self, event):
         el = self.plot.current_frame
         if isinstance(el, Dataset):

holoviews/streams.py

@@ -22,6 +22,17 @@
 # Types supported by Pointer derived streams
 pointer_types = (Number, str, tuple)+util.datetime_types
 
+POPUP_POSITIONS = [
+    "top_right",
+    "top_left",
+    "bottom_left",
+    "bottom_right",
+    "right",
+    "left",
+    "top",
+    "bottom",
+]
+
 class _SkipTrigger: pass
 
 
@@ -1255,9 +1266,17 @@ class LinkedStream(Stream):
     supplying stream data.
     """
 
-    def __init__(self, linked=True, popup=None, **params):
+    def __init__(self, linked=True, popup=None, popup_position=POPUP_POSITIONS[0], popup_anchor=None, **params):
+        if popup_position not in POPUP_POSITIONS:
+            raise ValueError(
+                f"Invalid popup_position: {popup_position!r}; "
+                f"expect one of {POPUP_POSITIONS}"
+            )
+
         super().__init__(linked=linked, **params)
         self.popup = popup
+        self.popup_position = popup_position
+        self.popup_anchor = popup_anchor
 
 
 class PointerX(LinkedStream):