Fixed up restoring of previously selected layer

Stored number is now interpreted as "global layer index".
mapeditor · Jan 31, 2017 · a02c667 · a02c667
1 parent 782893a
commit a02c667
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Showing 3 changed files with 41 additions and 7 deletions.
diff --git a/src/libtiled/layer.cpp b/src/libtiled/layer.cpp
@@ -35,7 +35,7 @@
 #include "objectgroup.h"
 #include "tilelayer.h"
 
-using namespace Tiled;
+namespace Tiled {
 
 Layer::Layer(TypeFlag type, const QString &name, int x, int y) :
     Object(LayerType),
@@ -212,3 +212,36 @@ Layer *LayerIterator::previous()
 
     return layer;
 }
+
+/**
+ * Returns the global layer index for the given \a layer. Obtained by iterating
+ * the layer's map while incrementing the index until layer is found.
+ */
+int globalIndex(Layer *layer)
+{
+    if (!layer)
+        return -1;
+
+    LayerIterator counter(layer->map());
+    int index = 0;
+    while (counter.next() && counter.currentLayer() != layer)
+        ++index;
+
+    return index;
+}
+
+/**
+ * Returns the layer at the given global \a index.
+ *
+ * \sa globalIndex()
+ */
+Layer *layerAtGlobalIndex(const Map *map, int index)
+{
+    LayerIterator counter(map);
+    while (counter.next() && index > 0)
+        --index;
+
+    return counter.currentLayer();
+}
+
+} // namespace Tiled
diff --git a/src/libtiled/layer.h b/src/libtiled/layer.h
@@ -321,6 +321,9 @@ inline bool LayerIterator::hasParent() const
 }
 
 
+TILEDSHARED_EXPORT int globalIndex(Layer *layer);
+TILEDSHARED_EXPORT Layer *layerAtGlobalIndex(const Map *map, int index);
+
 } // namespace Tiled
 
 #endif // LAYER_H
diff --git a/src/tiled/mapeditor.cpp b/src/tiled/mapeditor.cpp
@@ -316,10 +316,9 @@ void MapEditor::addDocument(Document *document)
         view->horizontalScrollBar()->setSliderPosition(hor);
         view->verticalScrollBar()->setSliderPosition(ver);
 
-        // todo: find a way to restore selected layer
-        int layer = mapState.value(QLatin1String("selectedLayer")).toInt();
-        if (layer > 0 && layer < mapDocument->map()->layerCount())
-            mapDocument->setCurrentLayer(mapDocument->map()->layerAt(layer));
+        int layerIndex = mapState.value(QLatin1String("selectedLayer")).toInt();
+        if (Layer *layer = layerAtGlobalIndex(mapDocument->map(), layerIndex))
+            mapDocument->setCurrentLayer(layer);
     }
 }
 
@@ -337,8 +336,7 @@ void MapEditor::removeDocument(Document *document)
         mapState.insert(QLatin1String("scale"), mapView->zoomable()->scale());
         mapState.insert(QLatin1String("scrollX"), mapView->horizontalScrollBar()->sliderPosition());
         mapState.insert(QLatin1String("scrollY"), mapView->verticalScrollBar()->sliderPosition());
-        // todo: find a good way to store a layer reference now that it is a hierarchy
-        mapState.insert(QLatin1String("selectedLayer"), mapDocument->layerIndex(mapDocument->currentLayer()));
+        mapState.insert(QLatin1String("selectedLayer"), globalIndex(mapDocument->currentLayer()));
         mMapStates.insert(mapDocument->fileName(), mapState);
 
         Preferences *prefs = Preferences::instance();