Bugfix: crash when opening Marker Detail.

Introduced in 5b4b54694c

src/main/java/de/dennisguse/opentracks/data/MarkerIterator.java

@@ -24,6 +24,12 @@ class MarkerIterator extends AutoCloseableIterator<Marker> {
         cursor = contentProviderUtils.getMarkerCursor(trackId, maxCount);
     }
 
+    @NonNull
+    @Override
+    public Marker get() {
+        return contentProviderUtils.createMarker(cursor);
+    }
+
     @Override
     public boolean hasNext() {
         if (cursor == null) {
@@ -38,7 +44,7 @@ class MarkerIterator extends AutoCloseableIterator<Marker> {
         if (cursor == null || !cursor.moveToNext()) {
             throw new NoSuchElementException();
         }
-        return contentProviderUtils.createMarker(cursor);
+        return get();
     }
 
     @Override

src/main/java/de/dennisguse/opentracks/data/TrackPointIterator.java

@@ -33,13 +33,19 @@ class TrackPointIterator extends AutoCloseableIterator<TrackPoint> {
         return !cursor.isLast() && !cursor.isAfterLast();
     }
 
+    @Override
+    @NonNull
+    public TrackPoint get() {
+        return ContentProviderUtils.fillTrackPoint(cursor, indexes);
+    }
+
     @Override
     @NonNull
     public TrackPoint next() {
         if (cursor == null || !cursor.moveToNext()) {
             throw new NoSuchElementException();
         }
-        return ContentProviderUtils.fillTrackPoint(cursor, indexes);
+        return get();
     }
 
     @Override

src/main/java/de/dennisguse/opentracks/ui/markers/MarkerDetailActivity.java

@@ -123,7 +123,7 @@ public class MarkerDetailActivity extends AbstractActivity implements DeleteMark
         @NonNull
         public Fragment createFragment(int position) {
             markerAutoCloseableIterator.moveToPosition(position);
-            return MarkerDetailFragment.newInstance(markerAutoCloseableIterator.next().id());
+            return MarkerDetailFragment.newInstance(markerAutoCloseableIterator.get(position).id());
         }
 
         @Override
@@ -133,8 +133,7 @@ public class MarkerDetailActivity extends AbstractActivity implements DeleteMark
 
         @Nullable
         public CharSequence getPageTitle(int position) {
-            markerAutoCloseableIterator.moveToPosition(position);
-            return getString(R.string.marker_detail_title, position + 1, getItemCount(), markerAutoCloseableIterator.next().name());
+            return getString(R.string.marker_detail_title, position + 1, getItemCount(), markerAutoCloseableIterator.get().name());
         }
     }
 }

src/main/java/de/dennisguse/opentracks/util/AutoCloseableIterator.java

@@ -1,5 +1,7 @@
 package de.dennisguse.opentracks.util;
 
+import androidx.annotation.NonNull;
+
 import java.util.Iterator;
 
 public abstract class AutoCloseableIterator<T> implements Iterator<T>, AutoCloseable {
@@ -13,5 +15,14 @@ public abstract class AutoCloseableIterator<T> implements Iterator<T>, AutoClose
 
     public abstract boolean moveToPosition(int position);
 
+    @NonNull
+    public abstract T get();
+
+    @NonNull
+    public T get(int position) {
+        moveToPosition(position);
+        return get();
+    }
+
     public abstract int getCount();
 }