Merge pull request #444 from orangemug/feature/issue-433

Added color swatch to <FeatureLayerPopup/>

src/components/map/FeatureLayerPopup.jsx

@@ -1,6 +1,7 @@
 import React from 'react'
 import PropTypes from 'prop-types'
 import LayerIcon from '../icons/LayerIcon'
+import {latest, expression, function as styleFunction} from '@mapbox/mapbox-gl-style-spec'
 
 function groupFeaturesBySourceLayer(features) {
   const sources = {}
@@ -28,7 +29,59 @@ function groupFeaturesBySourceLayer(features) {
 class FeatureLayerPopup extends React.Component {
   static propTypes = {
     onLayerSelect: PropTypes.func.isRequired,
-    features: PropTypes.array
+    features: PropTypes.array,
+    zoom: PropTypes.number,
+  }
+
+  _getFeatureColor(feature, zoom) {
+    try {
+      const paintProps = feature.layer.paint;
+      let propName;
+
+      if(paintProps.hasOwnProperty("text-color") && paintProps["text-color"]) {
+        propName = "text-color";
+      }
+      else if (paintProps.hasOwnProperty("fill-color") && paintProps["fill-color"]) {
+        propName = "fill-color";
+      }
+      else if (paintProps.hasOwnProperty("line-color") && paintProps["line-color"]) {
+        propName = "line-color";
+      }
+      else if (paintProps.hasOwnProperty("fill-extrusion-color") && paintProps["fill-extrusion-color"]) {
+        propName = "fill-extrusion-color";
+      }
+
+      if(propName) {
+        const propertySpec = latest["paint_"+feature.layer.type][propName];
+
+        let color = feature.layer.paint[propName];
+
+        if(typeof(color) === "object") {
+          if(color.stops) {
+            color = styleFunction.convertFunction(color, propertySpec);
+          }
+
+          const exprResult = expression.createExpression(color, propertySpec);
+          const val = exprResult.value.evaluate({
+            zoom: zoom
+          }, feature);
+          return val.toString();
+        }
+        else {
+          return color;
+        }
+      }
+      else {
+        // Default color
+        return "black";
+      }
+    }
+    // This is quite complex, just incase there's an edgecase we're missing
+    // always return black if we get an unexpected error.
+    catch (err) {
+      console.error("Unable to get feature color, error:", err);
+      return "black";
+    }
   }
 
   render() {
@@ -36,21 +89,31 @@ class FeatureLayerPopup extends React.Component {
 
     const items = Object.keys(sources).map(vectorLayerId => {
       const layers = sources[vectorLayerId].map((feature, idx) => {
-        return <label
-          key={idx}
-          className="maputnik-popup-layer"
-          onClick={() => {
-            this.props.onLayerSelect(feature.layer.id)
-          }}
+        const featureColor = this._getFeatureColor(feature, this.props.zoom);
+
+        return <div
+            key={idx}
+            className="maputnik-popup-layer"
         >
-          <LayerIcon type={feature.layer.type} style={{
-            width: 14,
-            height: 14,
-            paddingRight: 3
-          }}/>
-          {feature.layer.id}
-          {feature.counter && <span> × {feature.counter}</span>}
-        </label>
+          <div
+            className="maputnik-popup-layer__swatch" 
+            style={{background: featureColor}}
+          ></div>
+          <label
+            className="maputnik-popup-layer__label"
+            onClick={() => {
+              this.props.onLayerSelect(feature.layer.id)
+            }}
+          >
+            <LayerIcon type={feature.layer.type} style={{
+              width: 14,
+              height: 14,
+              paddingRight: 3
+            }}/>
+            {feature.layer.id}
+            {feature.counter && <span> × {feature.counter}</span>}
+          </label>
+        </div>
       })
       return <div key={vectorLayerId}>
         <div className="maputnik-popup-layer-id">{vectorLayerId}</div>

src/components/map/MapboxGlMap.jsx

@@ -166,14 +166,18 @@ export default class MapboxGlMap extends React.Component {
         if(this.props.inspectModeEnabled) {
           return renderPopup(<FeaturePropertyPopup features={features} />, tmpNode);
         } else {
-          return renderPopup(<FeatureLayerPopup features={features} onLayerSelect={this.props.onLayerSelect} />, tmpNode);
+          return renderPopup(<FeatureLayerPopup features={features} onLayerSelect={this.props.onLayerSelect} zoom={this.state.zoom} />, tmpNode);
         }
       }
     })
     map.addControl(inspect)
 
     map.on("style.load", () => {
-      this.setState({ map, inspect });
+      this.setState({
+        map,
+        inspect,
+        zoom: map.getZoom()
+      });
       if(this.props.inspectModeEnabled) {
         inspect.toggleInspector();
       }
@@ -185,6 +189,12 @@ export default class MapboxGlMap extends React.Component {
         map: this.state.map
       })
     })
+
+    map.on("zoom", e => {
+      this.setState({
+        zoom: map.getZoom()
+      });
+    })
   }
 
   render() {

src/styles/_popup.scss

@@ -1,4 +1,15 @@
 .maputnik-popup-layer {
+  display: flex;
+  flex-direction: row;
+}
+
+.maputnik-popup-layer__swatch {
+  display: inline-block;
+  width: 5px;
+  align-content: stretch;
+}
+
+.maputnik-popup-layer__label {
   display: block;
   color: $color-lowgray;
   cursor: pointer;