Mobile: implement follow mode

mobile/plugins/user-location.user.js

@@ -21,6 +21,7 @@
 window.plugin.userLocation = function() {};
 
 window.plugin.userLocation.locationLayer = new L.LayerGroup();
+window.plugin.userLocation.follow = false;
 
 window.plugin.userLocation.setup = function() {
   $('<style>').prop('type', 'text/css').html('@@INCLUDESTRING:mobile/plugins/user-location.css@@').appendTo('head');
@@ -59,10 +60,20 @@ window.plugin.userLocation.setup = function() {
   window.plugin.userLocation.circle = circle;
   window.plugin.userLocation.icon = icon;
 
+  window.map.on('movestart', window.plugin.userLocation.onMoveStart);
   window.map.on('zoomend', window.plugin.userLocation.onZoomEnd);
   window.plugin.userLocation.onZoomEnd();
 };
 
+window.plugin.userLocation.onMoveStart = function(e) {
+  if(window.plugin.userLocation.moving)
+    return;
+
+  window.plugin.userLocation.follow = false;
+  if(typeof android !== 'undefined' && android && android.setFollowMode)
+    android.setFollowMode(window.plugin.userLocation.follow);
+};
+
 window.plugin.userLocation.onZoomEnd = function() {
   if(window.map.getZoom() < 16)
     window.plugin.userLocation.locationLayer.removeLayer(window.plugin.userLocation.circle);
@@ -71,6 +82,13 @@ window.plugin.userLocation.onZoomEnd = function() {
 };
 
 window.plugin.userLocation.locate = function(lat, lng, accuracy) {
+  if(window.plugin.userLocation.follow) {
+    window.plugin.userLocation.follow = false;
+    if(typeof android !== 'undefined' && android && android.setFollowMode)
+      android.setFollowMode(window.plugin.userLocation.follow);
+    return;
+  }
+
   var latlng = new L.LatLng(lat, lng);
 
   var latAccuracy = 180 * accuracy / 40075017;
@@ -85,12 +103,22 @@ window.plugin.userLocation.locate = function(lat, lng, accuracy) {
   zoom = Math.min(zoom,17);
 
   window.map.setView(latlng, zoom);
+
+  window.plugin.userLocation.follow = true;
+  if(typeof android !== 'undefined' && android && android.setFollowMode)
+    android.setFollowMode(window.plugin.userLocation.follow);
 }
 
 window.plugin.userLocation.onLocationChange = function(lat, lng) {
   var latlng = new L.LatLng(lat, lng);
   window.plugin.userLocation.marker.setLatLng(latlng);
   window.plugin.userLocation.circle.setLatLng(latlng);
+
+  if(window.plugin.userLocation.follow) {
+    window.plugin.userLocation.moving = true;
+    window.map.setView(latlng);
+    window.plugin.userLocation.moving = false;
+  }
 };
 
 window.plugin.userLocation.onOrientationChange = function(direction) {

mobile/src/com/cradle/iitc_mobile/IITC_JSInterface.java

@@ -189,4 +189,14 @@ public class IITC_JSInterface {
             }
         });
     }
+
+    @JavascriptInterface
+    public void setFollowMode(final boolean follow) {
+        mIitc.runOnUiThread(new Runnable() {
+            @Override
+            public void run() {
+                mIitc.getUserLocation().setFollowMode(follow);
+            }
+        });
+    }
 }

mobile/src/com/cradle/iitc_mobile/IITC_Mobile.java

@@ -400,17 +400,31 @@ public class IITC_Mobile extends Activity implements OnSharedPreferenceChangeLis
 
     @Override
     public boolean onPrepareOptionsMenu(Menu menu) {
-        if (mNavigationHelper != null) {
-            boolean visible = !mNavigationHelper.isDrawerOpened();
+        boolean visible = false;
+        if (mNavigationHelper != null)
+            visible = !mNavigationHelper.isDrawerOpened();
 
-            for (int i = 0; i < menu.size(); i++)
-                if (menu.getItem(i).getItemId() != R.id.action_settings) {
-                    // clear cookies is part of the advanced menu
-                    if (menu.getItem(i).getItemId() == R.id.menu_clear_cookies) {
-                        menu.getItem(i).setVisible(mAdvancedMenu & visible);
-                    } else {
-                        menu.getItem(i).setVisible(visible);
-                    }
+        for (int i = 0; i < menu.size(); i++) {
+            MenuItem item = menu.getItem(i);
+
+            switch (item.getItemId()) {
+                case R.id.action_settings:
+                    item.setVisible(true);
+                    break;
+
+                case R.id.menu_clear_cookies:
+                    item.setVisible(mAdvancedMenu && visible);
+                    break;
+
+                case R.id.locate:
+                    item.setVisible(visible);
+                    item.setIcon(mUserLocation.isFollowing()
+                            ? R.drawable.ic_action_location_follow
+                            : R.drawable.ic_action_location_found);
+                    break;
+
+                default:
+                    item.setVisible(visible);
             }
         }
 
@@ -473,6 +487,7 @@ public class IITC_Mobile extends Activity implements OnSharedPreferenceChangeLis
     public void reloadIITC() {
         mNavigationHelper.reset();
         mMapSettings.reset();
+        mUserLocation.reset();
         mBackStack.clear();
         // iitc starts on map after reload
         mCurrentPane = Pane.MAP;
@@ -633,4 +648,8 @@ public class IITC_Mobile extends Activity implements OnSharedPreferenceChangeLis
     public IITC_MapSettings getMapSettings() {
         return mMapSettings;
     }
+
+    public IITC_UserLocation getUserLocation() {
+        return mUserLocation;
+    }
 }

mobile/src/com/cradle/iitc_mobile/IITC_UserLocation.java

@@ -25,6 +25,7 @@ public class IITC_UserLocation implements LocationListener, SensorEventListener
     private SensorManager mSensorManager = null;
     private float[] mValuesGravity = null, mValuesGeomagnetic = null;
     private double mOrientation = 0;
+    private boolean mFollowing = false;
 
     public IITC_UserLocation(IITC_Mobile iitc) {
         mIitc = iitc;
@@ -95,6 +96,10 @@ public class IITC_UserLocation implements LocationListener, SensorEventListener
         return mLastLocation != null;
     }
 
+    public boolean isFollowing() {
+        return mFollowing;
+    }
+
     public void locate() {
         // do not touch the javascript while iitc boots
         if (mIitc.isLoading()) return;
@@ -122,6 +127,15 @@ public class IITC_UserLocation implements LocationListener, SensorEventListener
         updateListeners();
     }
 
+    public void reset() {
+        setFollowMode(false);
+    }
+
+    public void setFollowMode(boolean follow) {
+        mFollowing = follow;
+        mIitc.invalidateOptionsMenu();
+    }
+
     /**
      * set the location mode to use. Available modes:
      * 0: don't show user's position