TileManager:

- set zoomMin/Max for current TileSource
- add zoom-level switch threshold
- add TileManager.getTile()
- remove releaseTiles()
- extract JobCompletedEvent from anonymous class

vtm/src/org/oscim/layers/tile/JobQueue.java

@@ -1,5 +1,4 @@
 /*
- * Copyright 2010, 2011, 2012 mapsforge.org
  * Copyright 2012, 2013 Hannes Janetzek
  *
  * This file is part of the OpenScienceMap project (http://www.opensciencemap.org).
@@ -20,11 +19,16 @@
 import static org.oscim.layers.tile.MapTile.State.LOADING;
 import static org.oscim.layers.tile.MapTile.State.NONE;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 /**
  * A JobQueue keeps the list of pending jobs for a MapView and prioritizes them.
  */
 public class JobQueue {
 
+	static final Logger log = LoggerFactory.getLogger(JobQueue.class);
+
 	private int mCurrentJob = 0;
 	private MapTile[] mJobs;
 
@@ -51,7 +55,12 @@ public synchronized void clear() {
 		MapTile[] tiles = mJobs;
 
 		for (int i = mCurrentJob, n = mJobs.length; i < n; i++) {
-			tiles[i].state = NONE;
+
+			if (tiles[i].state == LOADING)
+				tiles[i].state = NONE;
+			else
+				log.debug("wrong tile in queue {} {}", tiles[i], tiles[i].state);
+
 			tiles[i] = null;
 		}
 		mCurrentJob = 0;