Merge pull request #1760 from Conengmo/draggable-layer-control

Draggable layer control

Author: ocefpaf

folium/map.py

@@ -144,6 +144,9 @@ class LayerControl(MacroElement):
     autoZIndex : bool, default True
           If true the control assigns zIndexes in increasing order to all of
           its layers so that the order is preserved when switching them on/off.
+    draggable: bool, default False
+          By default the layer control has a fixed position. Set this argument
+          to True to allow dragging the control around.
     **kwargs
         Additional (possibly inherited) options. See
         https://leafletjs.com/reference.html#control-layers
@@ -153,7 +156,7 @@ class LayerControl(MacroElement):
     _template = Template(
         """
         {% macro script(this,kwargs) %}
-            var {{ this.get_name() }} = {
+            var {{ this.get_name() }}_layers = {
                 base_layers : {
                     {%- for key, val in this.base_layers.items() %}
                     {{ key|tojson }} : {{val}},
@@ -165,12 +168,16 @@ class LayerControl(MacroElement):
                     {%- endfor %}
                 },
             };
-            L.control.layers(
-                {{ this.get_name() }}.base_layers,
-                {{ this.get_name() }}.overlays,
+            let {{ this.get_name() }} = L.control.layers(
+                {{ this.get_name() }}_layers.base_layers,
+                {{ this.get_name() }}_layers.overlays,
                 {{ this.options|tojson }}
             ).addTo({{this._parent.get_name()}});
 
+            {%- if this.draggable %}
+            new L.Draggable({{ this.get_name() }}.getContainer()).enable();
+            {%- endif %}
+
         {% endmacro %}
         """
     )
@@ -180,13 +187,15 @@ def __init__(
         position: str = "topright",
         collapsed: bool = True,
         autoZIndex: bool = True,
+        draggable: bool = False,
         **kwargs: TypeJsonValue,
     ):
         super().__init__()
         self._name = "LayerControl"
         self.options = parse_options(
             position=position, collapsed=collapsed, autoZIndex=autoZIndex, **kwargs
         )
+        self.draggable = draggable
         self.base_layers: OrderedDict[str, str] = OrderedDict()
         self.overlays: OrderedDict[str, str] = OrderedDict()
 

tests/test_map.py

@@ -8,8 +8,8 @@
 import numpy as np
 import pytest
 
-from folium import Map
-from folium.map import CustomPane, Icon, Marker, Popup
+from folium import GeoJson, Map, TileLayer
+from folium.map import CustomPane, Icon, LayerControl, Marker, Popup
 from folium.utilities import normalize
 
 tmpl = """
@@ -19,6 +19,56 @@
 """.format
 
 
+def test_layer_control_initialization():
+    layer_control = LayerControl()
+    assert layer_control._name == "LayerControl"
+    assert layer_control.options["position"] == "topright"
+    assert layer_control.options["collapsed"] is True
+    assert layer_control.options["autoZIndex"] is True
+    assert layer_control.draggable is False
+    assert layer_control.base_layers == {}
+    assert layer_control.overlays == {}
+
+
+def test_layer_control_reset():
+    layer_control = LayerControl()
+    layer_control.base_layers = {"Layer1": "layer1"}
+    layer_control.overlays = {"Layer2": "layer2"}
+    layer_control.reset()
+    assert layer_control.base_layers == {}
+    assert layer_control.overlays == {}
+
+
+def test_layer_control_render():
+    m = Map(tiles=None)
+    layer1 = TileLayer().add_to(m)
+    layer2 = Marker([0, 0]).add_to(m)
+    layer3 = GeoJson({}).add_to(m)
+    layer1.control = True
+    layer2.control = False
+    layer3.control = True
+    layer1.layer_name = "Layer1"
+    layer2.layer_name = "Layer2"
+    layer3.layer_name = "Layer3"
+    layer1.get_name = lambda: "layer1"
+    layer2.get_name = lambda: "layer2"
+    layer3.get_name = lambda: "layer3"
+
+    layer_control = LayerControl().add_to(m)
+    layer_control.render()
+
+    assert layer_control.base_layers == {"Layer1": "layer1"}
+    assert layer_control.overlays == {"Layer3": "layer3"}
+
+
+def test_layer_control_draggable():
+    m = Map(tiles=None)
+    layer_control = LayerControl(draggable=True).add_to(m)
+    expected = f"new L.Draggable({ layer_control.get_name() }.getContainer()).enable();"
+    rendered = m.get_root().render()
+    assert normalize(expected) in normalize(rendered)
+
+
 def test_popup_ascii():
     popup = Popup("Some text.")
     _id = list(popup.html._children.keys())[0]