Added BarGraphItem.shape() to allow better mouse interaction

CHANGELOG

@@ -31,6 +31,7 @@ pyqtgraph-0.9.9  [unreleased]
     - Added FillBetweenItem.setCurves()
     - MultiPlotWidget now has setMinimumPlotHeight method and displays scroll bar
       when plots do not fit inside the widget.
+    - Added BarGraphItem.shape() to allow better mouse interaction
 
   Bugfixes:
     - PlotCurveItem now has correct clicking behavior--clicks within a few px

examples/BarGraphItem.py

@@ -28,7 +28,7 @@ win.addItem(bg3)
 # Final example shows how to handle mouse clicks:
 class BarGraph(pg.BarGraphItem):
     def mouseClickEvent(self, event):
-        print "clicked"
+        print("clicked")
 
 
 bg = BarGraph(x=x, y=y1*0.3+2, height=0.4+y1*0.2, width=0.8)

pyqtgraph/GraphicsScene/GraphicsScene.py

@@ -92,15 +92,11 @@ class GraphicsScene(QtGui.QGraphicsScene):
         
         self.clickEvents = []
         self.dragButtons = []
-        self.prepItems = weakref.WeakKeyDictionary()  ## set of items with prepareForPaintMethods
         self.mouseGrabber = None
         self.dragItem = None
         self.lastDrag = None
         self.hoverItems = weakref.WeakKeyDictionary()
         self.lastHoverEvent = None
-        #self.searchRect = QtGui.QGraphicsRectItem()
-        #self.searchRect.setPen(fn.mkPen(200,0,0))
-        #self.addItem(self.searchRect)
         
         self.contextMenu = [QtGui.QAction("Export...", self)]
         self.contextMenu[0].triggered.connect(self.showExportDialog)
@@ -437,10 +433,10 @@ class GraphicsScene(QtGui.QGraphicsScene):
         for item in items:
             if hoverable and not hasattr(item, 'hoverEvent'):
                 continue
-            shape = item.shape()
+            shape = item.shape() # Note: default shape() returns boundingRect()
             if shape is None:
                 continue
-            if item.mapToScene(shape).contains(point):
+            if shape.contains(item.mapFromScene(point)):
                 items2.append(item)
         
         ## Sort by descending Z-order (don't trust scene.itms() to do this either)

pyqtgraph/graphicsItems/BarGraphItem.py

@@ -47,16 +47,20 @@ class BarGraphItem(GraphicsObject):
             pens=None,
             brushes=None,
         )
+        self._shape = None
+        self.picture = None
         self.setOpts(**opts)
         
     def setOpts(self, **opts):
         self.opts.update(opts)
         self.picture = None
+        self._shape = None
         self.update()
         self.informViewBoundsChanged()
         
     def drawPicture(self):
         self.picture = QtGui.QPicture()
+        self._shape = QtGui.QPainterPath()
         p = QtGui.QPainter(self.picture)
         
         pen = self.opts['pen']
@@ -122,6 +126,10 @@ class BarGraphItem(GraphicsObject):
             if brushes is not None:
                 p.setBrush(fn.mkBrush(brushes[i]))
                 
+            if np.isscalar(x0):
+                x = x0
+            else:
+                x = x0[i]
             if np.isscalar(y0):
                 y = y0
             else:
@@ -130,9 +138,15 @@ class BarGraphItem(GraphicsObject):
                 w = width
             else:
                 w = width[i]
+            if np.isscalar(height):
+                h = height
+            else:
+                h = height[i]
                 
-            p.drawRect(QtCore.QRectF(x0[i], y, w, height[i]))
                 
+            rect = QtCore.QRectF(x, y, w, h)
+            p.drawRect(rect)
+            self._shape.addRect(rect)
             
         p.end()
         self.prepareGeometryChange()
@@ -148,4 +162,7 @@ class BarGraphItem(GraphicsObject):
             self.drawPicture()
         return QtCore.QRectF(self.picture.boundingRect())
     
-        
+    def shape(self):
+        if self.picture is None:
+            self.drawPicture()
+        return self._shape