Organizing communication responsibility layers between React and the leaflet webview

src/app/components/map/LeafLetMap.js

@@ -0,0 +1,55 @@
+import { Asset } from "expo-asset";
+import * as FileSystem from "expo-file-system";
+
+const HTML_FILE_PATH = require(`./Map.html`);
+
+const loadHTMLFile = async () => {
+  try {
+    const [{ localUri }] = await Asset.loadAsync(HTML_FILE_PATH);
+    const fileString = await FileSystem.readAsStringAsync(localUri);
+
+    return fileString;
+  } catch (error) {
+    console.warn(error);
+    console.warn("Unable to resolve index file");
+  }
+};
+
+function goToPosition(mapRef, lat, long) {
+  mapRef.injectJavaScript(`map.setView([${lat}, ${long}], 13);`);
+}
+
+const code_to_function = {
+  "1": clickCallback,
+  "2": markerCallback,
+};
+
+function clickCallback(payload) {
+  return {
+    object: "click",
+    cords: payload.content,
+  };
+}
+
+function markerCallback(payload) {
+  return {
+    object: "marker",
+    id: payload.content,
+  };
+}
+
+function parseInput(event) {
+  const payload = JSON.parse(event.nativeEvent.data);
+  return code_to_function[payload.code](payload);
+}
+
+function insertMarker(mapRef, props) {
+  mapRef.injectJavaScript(`
+  if (!(${props.ID} in markers)) {
+    markers[${props.ID}] = L.marker([${props.cords.lat}, ${props.cords.long}], 
+        {ID: ${props.ID}});
+    markers[${props.ID}].addTo(map).on('click', onPopupClick);
+  }
+  `);
+}
+export { loadHTMLFile, parseInput, insertMarker, goToPosition };

src/app/components/map/Map.html

@@ -96,7 +96,7 @@
       function onPopupClick(e) {
         var payload = {
           code: 2,
-          content: "marker selecionado " + this.options.ID,
+          content: this.options.ID,
         };
         window.ReactNativeWebView.postMessage(JSON.stringify(payload));
       }

src/app/components/map/OpenStreetMap.js

@@ -1,62 +1,41 @@
 import React, { useEffect, useState } from "react";
 import { View } from "react-native";
 import WebView from "react-native-webview";
-import { Asset } from "expo-asset";
-import * as FileSystem from "expo-file-system";
-
-const HTML_FILE_PATH = require(`./Map.html`);
-
-const loadHTMLFile = async () => {
-  try {
-    const [{ localUri }] = await Asset.loadAsync(HTML_FILE_PATH);
-    const fileString = await FileSystem.readAsStringAsync(localUri);
-
-    return fileString;
-  } catch (error) {
-    console.warn(error);
-    console.warn("Unable to resolve index file");
+import {
+  loadHTMLFile,
+  parseInput,
+  insertMarker,
+  goToPosition,
+} from "./LeafLetMap";
+
+function bindEventsToListeners(event, clickListener, markerListener) {
+  switch (event.object) {
+    case "click":
+      clickListener(event.cords);
+      break;
+    case "marker":
+      markerListener(event.id);
+      break;
+    default:
+      break;
   }
-};
-
-const code_to_function = {
-  "1": clickCallback,
-  "2": clickCallback,
-};
-
-function clickCallback(payload, props) {
-  console.log(payload.content);
-  props.clickListener(JSON.stringify(payload.content));
-}
-
-function parseInput(event, props) {
-  const payload = JSON.parse(event);
-  code_to_function[payload.code](payload, props);
 }
 
-function insertMarker(mapRef, props) {
-  mapRef.injectJavaScript(`
-  markers[${props.ID}] = L.marker([${props.cords.lat}, ${props.cords.long}], 
-  {ID: ${props.ID}});
-  markers[${props.ID}].addTo(map).on('click', onPopupClick);
-  `);
-}
-
-function goToPosition(mapRef, lat, long) {
-  mapRef.injectJavaScript(`map.setView([${lat}, ${long}], 13);`);
-}
-
-export default function OpenStreetMap(props) {
+export default function OpenStreetMap({
+  markersList,
+  animateToPosition,
+  clickListener,
+  markerListener,
+}) {
   const [mapRef, setMapRef] = useState(null);
-  const [finishedLoad, setFinishedLoad] = useState(false);
   const [webviewContent, setWebviewContent] = useState(null);
 
   if (mapRef != null) {
-    props.animateToPosition != null &&
-      goToPosition(mapRef, ...props.animateToPosition);
+    animateToPosition != null && goToPosition(mapRef, ...animateToPosition);
 
-    props.markersList != null &&
-      props.markersList.length > 0 &&
-      props.markersList.map((m) => insertMarker(mapRef, m));
+    markersList != null &&
+      markersList.length > 0 &&
+      markersList.map((m) => insertMarker(mapRef, m));
   }
 
   loadHTMLFile()
@@ -70,13 +49,14 @@ export default function OpenStreetMap(props) {
           setMapRef(webViewRef);
         }}
         onMessage={(event) => {
-          parseInput(event.nativeEvent.data, props);
+          bindEventsToListeners(
+            parseInput(event),
+            clickListener,
+            markerListener
+          );
         }}
         javaScriptEnabled={true}
         source={{ html: webviewContent }}
-        onLoad={() => {
-          setFinishedLoad(true);
-        }}
       />
     </View>
   );

src/app/screens/MapFeedScreen.js

@@ -5,6 +5,9 @@ import OpenStreetMap from "../components/map/OpenStreetMap";
 export default function MapFeedScreen() {
   const [position, setPosition] = useState(null);
   const [clickListener, setClickListener] = useState("");
+  const [markerListener, setMarkerListener] = useState("");
+
+  console.log(clickListener);
 
   const markers = [
     {
@@ -28,8 +31,9 @@ export default function MapFeedScreen() {
     <View style={styles.container}>
       <OpenStreetMap
         animateToPosition={position}
-        clickListener={setClickListener}
         markersList={markers}
+        clickListener={setClickListener}
+        markerListener={setMarkerListener}
       />
 
       <View style={styles.btn}>
@@ -53,7 +57,8 @@ export default function MapFeedScreen() {
       </View>
 
       <View style={styles.callback}>
-        <Text style={styles.txt}>{clickListener}</Text>
+        <Text style={styles.txt}>{JSON.stringify(clickListener)}</Text>
+        <Text style={styles.txt}>{JSON.stringify(markerListener)}</Text>
       </View>
     </View>
   );