changed structure to redefine axis via plotitem.setAxes (#391)

* changed structure to redefine axis via
plotitem.setAxes

* cleanuup

* remove old axesitems before adding new ones

* DEBUGGED plotitem.setAxes
NEW AxisItem.setOrientation (needed by plotitem.setAxes)
show/hide right axes after .setAxes()

Co-authored-by: Ogi Moore <ognyan.moore@gmail.com>

pyqtgraph/graphicsItems/AxisItem.py

@@ -45,11 +45,8 @@ class AxisItem(GraphicsWidget):
         GraphicsWidget.__init__(self, parent)
         self.label = QtGui.QGraphicsTextItem(self)
         self.picture = None
-        self.orientation = orientation
-        if orientation not in ['left', 'right', 'top', 'bottom']:
-            raise Exception("Orientation argument must be one of 'left', 'right', 'top', or 'bottom'.")
-        if orientation in ['left', 'right']:
-            self.label.rotate(-90)
+        self.orientation = None
+        self.setOrientation(orientation)
 
         self.style = {
             'tickTextOffset': [5, 2],  ## (horizontal, vertical) spacing between text and axis
@@ -111,6 +108,27 @@ class AxisItem(GraphicsWidget):
         self.grid = False
         #self.setCacheMode(self.DeviceCoordinateCache)
 
+    def setOrientation(self, orientation):
+        """
+        orientation = 'left', 'right', 'top', 'bottom'
+        """
+        if orientation != self.orientation:
+            if orientation not in ['left', 'right', 'top', 'bottom']:
+                raise Exception("Orientation argument must be one of 'left', 'right', 'top', or 'bottom'.")
+            #rotate absolute allows to change orientation multiple times:
+            if orientation in ['left', 'right']:
+                self.label.setRotation(-90)
+                if self.orientation:
+                    self._updateWidth()
+                    self.setMaximumHeight(16777215)
+            else:
+                self.label.setRotation(0) 
+                if self.orientation:
+                    self._updateHeight()
+                    self.setMaximumWidth(16777215)
+            self.orientation = orientation
+
+
     def setStyle(self, **kwds):
         """
         Set various style options.
@@ -514,6 +532,7 @@ class AxisItem(GraphicsWidget):
         self.unlinkFromView()
 
         self._linkedView = weakref.ref(view)
+
         if self.orientation in ['right', 'left']:
             view.sigYRangeChanged.connect(self.linkedViewChanged)
         else:

pyqtgraph/graphicsItems/PlotItem/PlotItem.py

@@ -153,9 +153,9 @@ class PlotItem(GraphicsWidget):
         
         self.legend = None
         
-        # Initialize axis items
+        ## Create and place axis items
         self.axes = {}
-        self.setAxisItems(axisItems)
+        self.setAxes(axisItems)
 
         self.titleLabel = LabelItem('', size='11pt', parent=self)
         self.layout.addItem(self.titleLabel, 0, 1)
@@ -260,6 +260,43 @@ class PlotItem(GraphicsWidget):
         if len(kargs) > 0:
             self.plot(**kargs)
         
+    def setAxes(self, axisItems):
+        """
+        Create and place axis items
+        For valid values for axisItems see __init__
+        """
+        for v in self.axes.values():
+            item = v['item']
+            self.layout.removeItem(item)
+            self.vb.removeItem(item)
+
+        self.axes = {}
+        if axisItems is None:
+            axisItems = {}
+        for k, pos in (('top', (1,1)), ('bottom', (3,1)), ('left', (2,0)), ('right', (2,2))):
+            axis = axisItems.get(k, None)
+            if axis:
+                axis.setOrientation(k)
+            else:
+                axis = AxisItem(orientation=k)
+            axis.linkToView(self.vb)
+            self.axes[k] = {'item': axis, 'pos': pos}            
+            self.layout.addItem(axis, *pos)
+            axis.setZValue(-1000)
+            axis.setFlag(axis.ItemNegativeZStacksBehindParent)
+        #show/hide axes:
+        all_dir = ['left', 'bottom', 'right', 'top']
+        if axisItems:
+            to_show = list(axisItems.keys())
+            to_hide = [a for a in all_dir if a not in to_show]
+        else:
+            to_show = all_dir[:2]
+            to_hide =  all_dir[2:]
+        for a  in to_hide:
+            self.hideAxis(a)
+        for a  in to_show:
+            self.showAxis(a)
+
     def implements(self, interface=None):
         return interface in ['ViewBoxWrapper']
 
@@ -1123,8 +1160,8 @@ class PlotItem(GraphicsWidget):
         Show or hide one of the plot's axes.
         axis must be one of 'left', 'bottom', 'right', or 'top'
         """
-        s = self.getScale(axis)
-        p = self.axes[axis]['pos']
+        s = self.getAxis(axis)
+        #p = self.axes[axis]['pos']
         if show:
             s.show()
         else: