Merge pull request #28640 from mantidproject/28053_colorbar_gridlines

docs/source/release/v5.1.0/mantidworkbench.rst

@@ -41,5 +41,6 @@ Bugfixes
 - Fixed being able to zoom in and out of colorbars on colorfill plots.
 - Fixed the default axis scale settings applying to the wrong axis.
 - Performing an overplot by dragging workspaces onto colorfill plots now correctly replaces the workspace.
+- Removed gridlines from the colorbar on colorfill plots.
 
 :ref:`Release 5.1.0 <v5.1.0>`

qt/applications/workbench/workbench/plotting/figuremanager.py

@@ -16,6 +16,7 @@ from matplotlib._pylab_helpers import Gcf
 from matplotlib.axes import Axes
 from matplotlib.backend_bases import FigureManagerBase
 from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg
+from matplotlib.collections import QuadMesh
 from mpl_toolkits.mplot3d.axes3d import Axes3D
 from qtpy.QtCore import QObject, Qt
 from qtpy.QtWidgets import QApplication, QLabel, QFileDialog
@@ -350,7 +351,8 @@ class FigureManagerWorkbench(FigureManagerBase, QObject):
         canvas = self.canvas
         axes = canvas.figure.get_axes()
         for ax in axes:
-            ax.grid(on)
+            if not any(isinstance(x, QuadMesh) for x in ax.collections):
+                ax.grid(on)
         canvas.draw_idle()
 
     def fit_toggle(self):