Implemented feature described by #30

plugins/LayerView/LayerViewProxy.py

@@ -0,0 +1,44 @@
+from PyQt5.QtCore import QObject, pyqtSignal, pyqtSlot, pyqtProperty
+from UM.Application import Application
+import LayerView
+class LayerViewProxy(QObject):
+    def __init__(self, parent = None):
+        super().__init__(parent)
+        self._current_layer = 0
+        self._controller = Application.getInstance().getController()
+        self._controller.activeViewChanged.connect(self._onActiveViewChanged)
+        self._onActiveViewChanged()
+    
+    currentLayerChanged = pyqtSignal()
+    maxLayersChanged = pyqtSignal()
+    
+    @pyqtProperty(int, notify = maxLayersChanged)
+    def numLayers(self):
+        active_view = self._controller.getActiveView()
+        #print("num max layers " , active_view.getMaxLayers())
+        return active_view.getMaxLayers()
+        #return 100
+    
+    @pyqtProperty(int, notify = currentLayerChanged)
+    def currentLayer(self):
+        active_view = self._controller.getActiveView()
+        if type(active_view) == LayerView.LayerView.LayerView:
+            return active_view.getCurrentLayer()
+    
+    @pyqtSlot(int)
+    def setCurrentLayer(self, layer_num):
+        active_view = self._controller.getActiveView()
+        if type(active_view) == LayerView.LayerView.LayerView:
+            active_view.setLayer(layer_num)
+            
+    def _onLayerChanged(self):
+        self.currentLayerChanged.emit()
+        
+    def _onMaxLayersChanged(self):
+        self.maxLayersChanged.emit()
+        
+    def _onActiveViewChanged(self):
+        active_view = self._controller.getActiveView()
+        if type(active_view) == LayerView.LayerView.LayerView:
+            active_view.currentLayerNumChanged.connect(self._onLayerChanged)
+            active_view.maxLayersChanged.connect(self._onMaxLayersChanged)