Geomaps: clear markers when switching maps (#53).

There is still a bug: new markers are added to *every* geomap.

See ticket 53.

deepamehta-geomaps/src/main/java/de/deepamehta/plugins/geomaps/GeomapsPlugin.java

@@ -70,6 +70,7 @@ public Geomap getGeomap(@PathParam("id") long geomapId) {
     @Path("/{id}/topic/{topic_id}")
     @Override
     public void addTopicToGeomap(@PathParam("id") long geomapId, @PathParam("topic_id") long topicId) {
+        logger.info("### Adding topic " + topicId + " to geomap " + geomapId);
         AssociationModel model = new AssociationModel("dm4.geomaps.geotopic_mapcontext",
             new TopicRoleModel(geomapId, "dm4.core.default"),
             new TopicRoleModel(topicId,  "dm4.topicmaps.topicmap_topic"));

deepamehta-geomaps/src/main/resources/web/script/topicmap_renderers/geomap_renderer.js

@@ -48,6 +48,10 @@ function GeoMapRenderer() {
         }
     }
 
+    this.clear = function() {
+        marker_layers["markers"].remove_all_markers()
+    }
+
     this.select_topic = function(topic_id) {
         // ### set_highlight_object(topic_id)
         return {
@@ -150,6 +154,20 @@ function GeoMapRenderer() {
         this.remove_marker = function(topic_id) {
             markers_layer.removeMarker(markers[topic_id])
         }
+
+        this.remove_all_markers = function() {
+            iterate_markers(function(marker) {
+                markers_layer.removeMarker(marker)
+            })
+        }
+
+        // ---
+
+        function iterate_markers(visitor_func) {
+            for (var topic_id in markers) {
+                visitor_func(markers[topic_id])
+            }
+        }
     }
 
     /**
@@ -179,6 +197,7 @@ function GeoMapRenderer() {
         }
 
         this.put_on_canvas = function(no_history_update) {
+            dm4c.canvas.clear()
             display_topics()
             restore_selection()
 
@@ -195,15 +214,16 @@ function GeoMapRenderer() {
 
         this.add_topic = function(id, type_uri, value, x, y) {
             if (x != undefined && y != undefined) {
-                if (LOG_GEOMAPS) dm4c.log("Geomap.add_topic(): adding topic to model\n..... id=" + id +
-                    ", type_uri=\"" + type_uri + "\", x=" + x + ", y=" + y)
+                if (LOG_GEOMAPS) dm4c.log("Geomap.add_topic(): adding topic to model of geomap " + topicmap_id +
+                    "\n..... id=" + id + ", type_uri=\"" + type_uri + "\", x=" + x + ", y=" + y)
                 // update DB
                 dm4c.restc.add_topic_to_geomap(topicmap_id, id)     // ### FIXME: add only once
                 // update memory
                 topics[id] = new GeomapTopic(id, type_uri, value, x, y)
             } else {
-                if (LOG_GEOMAPS) dm4c.log("Geomap.add_topic(): adding topic to model ABORTED -- topic has " +
-                    "no coordinates\n..... id=" + id + ", type_uri=\"" + type_uri + "\", value=\"" + value + "\"")
+                if (LOG_GEOMAPS) dm4c.log("Geomap.add_topic(): adding topic to model of geomap " + topicmap_id +
+                    " ABORTED -- topic has no coordinates\n..... id=" + id + ", type_uri=\"" + type_uri +
+                    "\", value=\"" + value + "\"")
             }
         }
 

deepamehta-webclient/src/main/resources/web/script/interfaces/topicmap_renderer.js

@@ -1,5 +1,10 @@
 /**
- * This interface is implemented by classes who render the left part of the DeepaMehta window (the "canvas").
+ * An abstraction of the view component that occupies the left part of the DeepaMehta window (the "canvas").
+ * The abstraction comprises:
+ *     - A model of the topics and association that are currently displayed.
+ *     - A model for the current selection.
+ *     - A model for the current translation.
+ *     - The view element (the "dom" property).
  *
  * The Webclient is coded to this interface.
  *
@@ -46,6 +51,11 @@ function TopicmapRenderer() {
      */
     this.remove_association = function(assoc_id, refresh_canvas) {}
 
+    /**
+     * Clears the model: removes all topics and associations. Resets the selection and translation.
+     */
+    this.clear = function() {}
+
     // ---
 
     /**
@@ -67,8 +77,6 @@ function TopicmapRenderer() {
 
     this.refresh = function() {}
 
-    this.clear = function() {}
-
     /**
      * @param   size    an object with "width" and "height" properties.
      */

deepamehta-webclient/src/main/resources/web/script/topicmap_renderers/canvas.js

@@ -193,6 +193,15 @@ function Canvas(width, height) {
 
     // ---
 
+    this.clear = function() {
+        // refresh GUI
+        translate(-trans_x, -trans_y)                       // reset translation
+        // update model
+        init_model()
+    }
+
+    // ---
+
     this.select_topic = function(topic_id) {
         var topic = dm4c.fetch_topic(topic_id)
         set_highlight_object(topic_id)
@@ -245,13 +254,6 @@ function Canvas(width, height) {
         draw()
     }
 
-    this.clear = function() {
-        // refresh GUI
-        translate(-trans_x, -trans_y)                       // reset translation
-        // update model
-        init_model()
-    }
-
     this.resize = function(size) {
         resize_canvas(size)
     }