From b0713cc0e7bd17261475a6b6f8e85ba827823e26 Mon Sep 17 00:00:00 2001
From: Jimmy Shih <jshih@google.com>
Date: Mon, 3 Dec 2012 10:17:33 -0800
Subject: [PATCH] Add synchronization when accessing waypoints in ChartView

---
 .../android/apps/mytracks/ChartView.java      | 66 +++++++++++--------
 1 file changed, 37 insertions(+), 29 deletions(-)

diff --git a/MyTracks/src/com/google/android/apps/mytracks/ChartView.java b/MyTracks/src/com/google/android/apps/mytracks/ChartView.java
index 44b30e677..165a20327 100644
--- a/MyTracks/src/com/google/android/apps/mytracks/ChartView.java
+++ b/MyTracks/src/com/google/android/apps/mytracks/ChartView.java
@@ -309,14 +309,18 @@ public class ChartView extends View {
    * @param waypoint the waypoint
    */
   public void addWaypoint(Waypoint waypoint) {
-    waypoints.add(waypoint);
+    synchronized (waypoints) {
+      waypoints.add(waypoint);
+    }
   }
 
   /**
    * Clears the waypoints.
    */
   public void clearWaypoints() {
-    waypoints.clear();
+    synchronized (waypoints) {
+      waypoints.clear();
+    }
   }
 
   /**
@@ -445,13 +449,15 @@ public class ChartView extends View {
         if (Math.abs(event.getY() - topBorder - spacer - markerHeight / 2) < markerHeight) {
           int minDistance = Integer.MAX_VALUE;
           Waypoint nearestWaypoint = null;
-          for (int i = 0; i < waypoints.size(); i++) {
-            Waypoint waypoint = waypoints.get(i);
-            int distance = Math.abs(
-                getX(getWaypointXValue(waypoint)) - (int) event.getX() - getScrollX());
-            if (distance < minDistance) {
-              minDistance = distance;
-              nearestWaypoint = waypoint;
+          synchronized (waypoints) {
+            for (int i = 0; i < waypoints.size(); i++) {
+              Waypoint waypoint = waypoints.get(i);
+              int distance = Math.abs(
+                  getX(getWaypointXValue(waypoint)) - (int) event.getX() - getScrollX());
+              if (distance < minDistance) {
+                minDistance = distance;
+                nearestWaypoint = waypoint;
+              }
             }
           }
           if (nearestWaypoint != null && minDistance < markerWidth) {
@@ -543,27 +549,29 @@ public class ChartView extends View {
    * @param canvas the canvas
    */
   private void drawWaypoints(Canvas canvas) {
-    for (int i = 0; i < waypoints.size(); i++) {
-      final Waypoint waypoint = waypoints.get(i);
-      if (waypoint.getLocation() == null) {
-        continue;
+    synchronized (waypoints) {
+      for (int i = 0; i < waypoints.size(); i++) {
+        final Waypoint waypoint = waypoints.get(i);
+        if (waypoint.getLocation() == null) {
+          continue;
+        }
+        double xValue = getWaypointXValue(waypoint);
+        if (xValue > maxX) {
+          continue;
+        }
+        canvas.save();
+        float x = getX(getWaypointXValue(waypoint));
+        canvas.drawLine(
+            x, topBorder + spacer + markerHeight / 2, x, topBorder + effectiveHeight, markerPaint);
+        canvas.translate(
+            x - (float) (markerWidth * MapOverlay.WAYPOINT_X_ANCHOR), topBorder + spacer);
+        if (waypoints.get(i).getType() == Waypoint.TYPE_STATISTICS) {
+          statisticsMarker.draw(canvas);
+        } else {
+          waypointMarker.draw(canvas);
+        }
+        canvas.restore();
       }
-      double xValue = getWaypointXValue(waypoint);
-      if (xValue > maxX) {
-        continue;
-      }
-      canvas.save();
-      float x = getX(getWaypointXValue(waypoint));
-      canvas.drawLine(
-          x, topBorder + spacer + markerHeight / 2, x, topBorder + effectiveHeight, markerPaint);
-      canvas.translate(x - (float) (markerWidth * MapOverlay.WAYPOINT_X_ANCHOR),
-          topBorder + spacer);
-      if (waypoints.get(i).getType() == Waypoint.TYPE_STATISTICS) {
-        statisticsMarker.draw(canvas);
-      } else {
-        waypointMarker.draw(canvas);
-      }
-      canvas.restore();
     }
   }